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Question 1
Correct
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A 25-year-old from West Africa presents with joint pain, muscle pain, and symptoms similar to the flu. In the past day or two, he has also developed stomach pain and diarrhea. During the examination, his temperature is measured at 38.7°C, and he experiences tenderness in the upper right quadrant of his abdomen along with an enlarged liver and spleen. He remembers having an itchy rash and a few blisters on his arm after swimming in a local river a few weeks ago. Blood tests show a significant increase in eosinophils.
What is the MOST appropriate initial treatment option?Your Answer: Praziquantel
Explanation:Schistosomiasis, also known as bilharzia, is a tropical disease caused by parasitic trematodes (flukes) of the Schistosoma type. It is transmitted through contaminated water that has been contaminated with faeces or urine containing eggs. The disease requires a specific freshwater snail as an intermediate host and human contact with water inhabited by the snail. There are five species of Schistosoma that cause human disease: S. japonicum, S. mansoni, S. haematobium, S. intercalatum, and S. mekongi. Schistosomiasis is a significant public health issue, second only to malaria, with over 200 million people infected worldwide. It is prevalent in the Middle East, Africa, and parts of South America and the Caribbean. Infection can manifest as acute or chronic.
Acute schistosomiasis is characterized by the early clinical sign of swimmers itch, which causes blisters and an urticarial response in the area where the parasite enters the skin. Most acute infections are asymptomatic, but some patients may develop an acute syndrome. The most common acute syndrome is known as Katayama fever, which typically occurs in individuals with no previous exposure. It is caused by an allergic reaction to the sudden release of highly antigenic eggs and usually presents a few weeks after initial exposure to S. japonicum. Symptoms of Katayama fever include fever, flu-like illness, arthralgia, myalgia, abdominal pain, diarrhea, and cough. Patients may also experience right upper quadrant tenderness and hepatosplenomegaly. An extremely high eosinophil count is commonly observed.
Chronic schistosomiasis can manifest as intestinal or urogenital forms. Intestinal schistosomiasis occurs when adult worms migrate from the liver to the mesenteric venules, where female worms continuously lay eggs. Common symptoms include abdominal pain and bloody diarrhea. Advanced cases may present with hepatosplenomegaly and portal hypertension. Schistosomiasis is the second most common cause of oesophageal varices worldwide. Urogenital schistosomiasis occurs when adult worms migrate to the vesical plexus. The hallmark sign is haematuria. In women, it may cause genital and vaginal lesions, as well as dyspareunia.
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This question is part of the following fields:
- Infectious Diseases
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Question 2
Incorrect
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A 21 year old college student comes to the emergency department complaining of feeling unwell, having a fever, and experiencing a severe sore throat. After evaluating the patient, you inform them that you suspect they may have contracted infectious mononucleosis. The patient inquires if it is possible to have caught this by kissing someone a week ago.
What is the usual duration of the incubation period for infectious mononucleosis?Your Answer: 7-14 days
Correct Answer: 4-8 weeks
Explanation:Glandular fever, also known as infectious mononucleosis or mono, is a clinical syndrome characterized by symptoms such as sore throat, fever, and swollen lymph nodes. It is primarily caused by the Epstein-Barr virus (EBV), with other viruses and infections accounting for the remaining cases. Glandular fever is transmitted through infected saliva and primarily affects adolescents and young adults. The incubation period is 4-8 weeks.
The majority of EBV infections are asymptomatic, with over 95% of adults worldwide having evidence of prior infection. Clinical features of glandular fever include fever, sore throat, exudative tonsillitis, lymphadenopathy, and prodromal symptoms such as fatigue and headache. Splenomegaly (enlarged spleen) and hepatomegaly (enlarged liver) may also be present, and a non-pruritic macular rash can sometimes occur.
Glandular fever can lead to complications such as splenic rupture, which increases the risk of rupture in the spleen. Approximately 50% of splenic ruptures associated with glandular fever are spontaneous, while the other 50% follow trauma. Diagnosis of glandular fever involves various investigations, including viral serology for EBV, monospot test, and liver function tests. Additional serology tests may be conducted if EBV testing is negative.
Management of glandular fever involves supportive care and symptomatic relief with simple analgesia. Antiviral medication has not been shown to be beneficial. It is important to identify patients at risk of serious complications, such as airway obstruction, splenic rupture, and dehydration, and provide appropriate management. Patients can be advised to return to normal activities as soon as possible, avoiding heavy lifting and contact sports for the first month to reduce the risk of splenic rupture.
Rare but serious complications associated with glandular fever include hepatitis, upper airway obstruction, cardiac complications, renal complications, neurological complications, haematological complications, chronic fatigue, and an increased risk of lymphoproliferative cancers and multiple sclerosis.
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This question is part of the following fields:
- Infectious Diseases
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Question 3
Correct
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A patient with rheumatoid arthritis presents after her granddaughter is diagnosed with chickenpox. Her granddaughter has spent the weekend staying with her, and she had close contact with her. She has been taking 50 mg of prednisolone once daily for six months. She has never had chickenpox herself.
Which ONE statement regarding her care is accurate?Your Answer: She should receive prophylactic varicella zoster Immunoglobulin (VZIG)
Explanation:Prophylactic VZIG is recommended for individuals at high risk who have had a significant exposure to varicella-zoster but have no known immunity (meaning they have not had chickenpox before). High-risk groups include neonates, pregnant women, the immunocompromised, and those on high dose steroids. For children on more than 2 mg/kg/day for more than 14 days, or adults on 40 mg/day for more than a week, it is important to temporarily increase their steroid dose during times of infection or stress. Stopping or reducing the dose of prednisolone would not be appropriate in this case. This patient is at high risk of adrenal insufficiency. Severe varicella infection can occur, leading to complications such as pneumonia, hepatitis, and DIC. It is important to note that varicella infection may not present with the typical rash and can have atypical or insidious symptoms. If a patient on high dose steroids develops varicella infection, they should be admitted for specialist review and receive intravenous aciclovir.
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This question is part of the following fields:
- Infectious Diseases
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Question 4
Correct
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A 75 year old man is brought into the emergency room by ambulance. He started with a cough about a week ago but now appears somewhat confused and drowsy. His vital signs are as follows:
Temperature: 37.9ºC
Blood pressure: 98/65 mmHg
Respiration rate: 22 rpm
Pulse rate: 105 bpm
Blood glucose: 6.9 mmol/l
SpO2: 91% on air rising to 96% on 2L oxygen
Which of the above parameters, if any, would be a cause for concern indicating sepsis?Your Answer: SpO2 of 91% on air rising to 96% on 2L oxygen
Explanation:This individual’s condition should be closely monitored and they should be promptly placed on the Sepsis pathway due to the presence of red flags. Please refer to the notes below for a comprehensive list of red and amber flags.
Further Reading:
There are multiple definitions of sepsis, leading to confusion among healthcare professionals. The Sepsis 3 definition describes sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection. The Sepsis 2 definition includes infection plus two or more SIRS criteria. The NICE definition states that sepsis is a clinical syndrome triggered by the presence of infection in the blood, activating the body’s immune and coagulation systems. The Sepsis Trust defines sepsis as a dysregulated host response to infection mediated by the immune system, resulting in organ dysfunction, shock, and potentially death.
The confusion surrounding sepsis terminology is further compounded by the different versions of sepsis definitions, known as Sepsis 1, Sepsis 2, and Sepsis 3. The UK organizations RCEM and NICE have not fully adopted the changes introduced in Sepsis 3, causing additional confusion. While Sepsis 3 introduces the use of SOFA scores and abandons SIRS criteria, NICE and the Sepsis Trust have rejected the use of SOFA scores and continue to rely on SIRS criteria. This discrepancy creates challenges for emergency department doctors in both exams and daily clinical practice.
To provide some clarity, RCEM now recommends referring to national standards organizations such as NICE, SIGN, BTS, or others relevant to the area. The Sepsis Trust, in collaboration with RCEM and NICE, has published a toolkit that serves as a definitive reference point for sepsis management based on the sepsis 3 update.
There is a consensus internationally that the terms SIRS and severe sepsis are outdated and should be abandoned. Instead, the terms sepsis and septic shock should be used. NICE defines septic shock as a life-threatening condition characterized by low blood pressure despite adequate fluid replacement and organ dysfunction or failure. Sepsis 3 defines septic shock as persisting hypotension requiring vasopressors to maintain a mean arterial pressure of 65 mmHg or more, along with a serum lactate level greater than 2 mmol/l despite adequate volume resuscitation.
NICE encourages clinicians to adopt an approach of considering sepsis in all patients, rather than relying solely on strict definitions. Early warning or flag systems can help identify patients with possible sepsis.
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This question is part of the following fields:
- Infectious Diseases
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Question 5
Correct
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A 45 year old patient is brought to the emergency department (ED) by a family member. The patient began experiencing coughing symptoms ten days ago, but within the past 48 hours, they have developed a high fever, difficulty breathing during mild exertion, and the family reports that the patient appears confused. It is noted that the patient is currently taking azathioprine for the treatment of rheumatoid arthritis.
Upon assessing the patient's vital signs, you decide to initiate the sepsis 6 pathway. What is the recommended timeframe for implementing the 'sepsis six'?Your Answer: 1 hour
Explanation:The sepsis 6 pathway is a time-sensitive protocol that should be started promptly and all 6 initial steps should be completed within 1 hour. It is important not to confuse the sepsis 6 pathway with the 6 hour care bundle. Time is of the essence when managing septic patients, and initiating the sepsis 6 pathway immediately has been proven to enhance survival rates in sepsis patients.
Further Reading:
There are multiple definitions of sepsis, leading to confusion among healthcare professionals. The Sepsis 3 definition describes sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection. The Sepsis 2 definition includes infection plus two or more SIRS criteria. The NICE definition states that sepsis is a clinical syndrome triggered by the presence of infection in the blood, activating the body’s immune and coagulation systems. The Sepsis Trust defines sepsis as a dysregulated host response to infection mediated by the immune system, resulting in organ dysfunction, shock, and potentially death.
The confusion surrounding sepsis terminology is further compounded by the different versions of sepsis definitions, known as Sepsis 1, Sepsis 2, and Sepsis 3. The UK organizations RCEM and NICE have not fully adopted the changes introduced in Sepsis 3, causing additional confusion. While Sepsis 3 introduces the use of SOFA scores and abandons SIRS criteria, NICE and the Sepsis Trust have rejected the use of SOFA scores and continue to rely on SIRS criteria. This discrepancy creates challenges for emergency department doctors in both exams and daily clinical practice.
To provide some clarity, RCEM now recommends referring to national standards organizations such as NICE, SIGN, BTS, or others relevant to the area. The Sepsis Trust, in collaboration with RCEM and NICE, has published a toolkit that serves as a definitive reference point for sepsis management based on the sepsis 3 update.
There is a consensus internationally that the terms SIRS and severe sepsis are outdated and should be abandoned. Instead, the terms sepsis and septic shock should be used. NICE defines septic shock as a life-threatening condition characterized by low blood pressure despite adequate fluid replacement and organ dysfunction or failure. Sepsis 3 defines septic shock as persisting hypotension requiring vasopressors to maintain a mean arterial pressure of 65 mmHg or more, along with a serum lactate level greater than 2 mmol/l despite adequate volume resuscitation.
NICE encourages clinicians to adopt an approach of considering sepsis in all patients, rather than relying solely on strict definitions. Early warning or flag systems can help identify patients with possible sepsis.
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This question is part of the following fields:
- Infectious Diseases
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Question 6
Correct
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A 35 year old male with a history of IV drug use presents to the emergency department complaining of feeling generally unwell, lethargy, and having a fever for the past 2 days. The initial observations are as follows:
- Temperature: 38.6ºC
- Pulse rate: 124 bpm
- Blood pressure: 126/80 mmHg
- Respiration rate: 22 bpm
- Oxygen saturation: 98% on room air
During chest auscultation, an audible murmur is detected, leading to a suspicion of infective endocarditis. What is the most likely organism causing this infection?Your Answer: Staphylococcus aureus
Explanation:Staphylococcus aureus is the primary organism responsible for infective endocarditis in individuals who use intravenous drugs (IVDUs). In fact, it is not only the most common cause of infective endocarditis overall, but also specifically in IVDUs. Please refer to the additional notes for more detailed information.
Further Reading:
Infective endocarditis (IE) is an infection that affects the innermost layer of the heart, known as the endocardium. It is most commonly caused by bacteria, although it can also be caused by fungi or viruses. IE can be classified as acute, subacute, or chronic depending on the duration of illness. Risk factors for IE include IV drug use, valvular heart disease, prosthetic valves, structural congenital heart disease, previous episodes of IE, hypertrophic cardiomyopathy, immune suppression, chronic inflammatory conditions, and poor dental hygiene.
The epidemiology of IE has changed in recent years, with Staphylococcus aureus now being the most common causative organism in most industrialized countries. Other common organisms include coagulase-negative staphylococci, streptococci, and enterococci. The distribution of causative organisms varies depending on whether the patient has a native valve, prosthetic valve, or is an IV drug user.
Clinical features of IE include fever, heart murmurs (most commonly aortic regurgitation), non-specific constitutional symptoms, petechiae, splinter hemorrhages, Osler’s nodes, Janeway’s lesions, Roth’s spots, arthritis, splenomegaly, meningism/meningitis, stroke symptoms, and pleuritic pain.
The diagnosis of IE is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Major criteria include positive blood cultures with typical microorganisms and positive echocardiogram findings. Minor criteria include fever, vascular phenomena, immunological phenomena, and microbiological phenomena. Blood culture and echocardiography are key tests for diagnosing IE.
In summary, infective endocarditis is an infection of the innermost layer of the heart that is most commonly caused by bacteria. It can be classified as acute, subacute, or chronic and can be caused by a variety of risk factors. Staphylococcus aureus is now the most common causative organism in most industrialized countries. Clinical features include fever, heart murmurs, and various other symptoms. The diagnosis is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Blood culture and echocardiography are important tests for diagnosing IE.
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This question is part of the following fields:
- Infectious Diseases
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Question 7
Incorrect
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A 3-year-old girl presents with a temperature of 39 degrees. She appears fussy, and a non-blanching rash is observed on her abdomen. Tragically, she passes away later that day from Meningococcal septicaemia.
To whom should a report be submitted?Your Answer: NHS England
Correct Answer: Consultant in Communicable Disease Control
Explanation:Registered medical practitioners in England and Wales are legally obligated to inform a designated official from the Local Authority if they suspect a patient has contracted specific infectious diseases. For more information on which diseases and their causative organisms require reporting, please refer to the following resource: Notifiable diseases and causative organisms: how to report.
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This question is part of the following fields:
- Infectious Diseases
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Question 8
Correct
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A 2-year-old child is diagnosed with a condition that you identify as a notifiable infection. You fill out the notification form and reach out to the local health protection team.
Which of the following is the LEAST probable diagnosis?Your Answer: Roseola infantum
Explanation:Public Health England (PHE) has a primary goal of swiftly identifying potential disease outbreaks and epidemics. While accuracy of diagnosis is important, it is not the main focus. Since 1968, clinical suspicion of a notifiable infection has been sufficient for reporting.
Registered medical practitioners (RMPs) are legally obligated to notify the designated proper officer at their local council or local health protection team (HPT) if they suspect cases of certain infectious diseases.
The Health Protection (Notification) Regulations 2010 specify the diseases that RMPs must report to the proper officers at local authorities. These diseases include acute encephalitis, acute infectious hepatitis, acute meningitis, acute poliomyelitis, anthrax, botulism, brucellosis, cholera, COVID-19, diphtheria, enteric fever (typhoid or paratyphoid fever), food poisoning, haemolytic uraemic syndrome (HUS), infectious bloody diarrhoea, invasive group A streptococcal disease, Legionnaires’ disease, leprosy, malaria, measles, meningococcal septicaemia, mumps, plague, rabies, rubella, severe acute respiratory syndrome (SARS), scarlet fever, smallpox, tetanus, tuberculosis, typhus, viral haemorrhagic fever (VHF), whooping cough, and yellow fever.
It is worth noting that roseola infantum is not considered a notifiable disease, making it the least likely option among the diseases listed above. -
This question is part of the following fields:
- Infectious Diseases
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Question 9
Correct
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A 45-year-old woman is admitted to the hospital with a high temperature, cough, and difficulty breathing. After conducting additional tests, she is diagnosed with a notifiable illness. You fill out the notification form and get in touch with the local health protection team.
Which of the following is the LEAST probable diagnosis?Your Answer: Influenza
Explanation:Public Health England (PHE) has a primary goal of swiftly identifying potential disease outbreaks and epidemics. While accuracy of diagnosis is important, it takes a backseat to the speed of detection. Since 1968, the clinical suspicion of a notifiable infection has been sufficient for reporting purposes.
Registered medical practitioners (RMPs) are legally obligated to notify the designated proper officer at their local council or local health protection team (HPT) when they suspect cases of certain infectious diseases.
The Health Protection (Notification) Regulations 2010 specify the diseases that RMPs must report to the proper officers. These diseases include acute encephalitis, acute infectious hepatitis, acute meningitis, acute poliomyelitis, anthrax, botulism, brucellosis, cholera, COVID-19, diphtheria, enteric fever (typhoid or paratyphoid fever), food poisoning, haemolytic uraemic syndrome (HUS), infectious bloody diarrhoea, invasive group A streptococcal disease, Legionnaires’ disease, leprosy, malaria, measles, meningococcal septicaemia, mumps, plague, rabies, rubella, severe acute respiratory syndrome (SARS), scarlet fever, smallpox, tetanus, tuberculosis, typhus, viral haemorrhagic fever (VHF), whooping cough, and yellow fever.
It is worth noting that influenza is not considered a notifiable disease, making it the least likely option among the diseases listed above.
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This question is part of the following fields:
- Infectious Diseases
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Question 10
Incorrect
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A 25-year-old college student comes to the emergency department complaining of a worsening sore throat, fever, and feeling unwell. The patient reports that the symptoms began 10 days ago. During the examination, the patient has a temperature of 38.0ºC, swollen lymph nodes in the neck, white patches on both tonsils, and tenderness in the right upper abdomen. Glandular fever is suspected.
What would be the most suitable approach to confirm the suspected diagnosis?Your Answer: Blood test for Epstein-Barr virus (EBV) viral serology
Correct Answer: FBC and monospot test
Explanation:For adults and children over the age of 12 who are suspected to have glandular fever and have a normal immune system, it is recommended to conduct a Full Blood Count (FBC) and a monospot test during the second week of the illness. The timing and choice of investigations for glandular fever vary depending on the patient’s age, immune system status, and duration of symptoms. For children under the age of 12 and individuals with compromised immune systems, it is advised to perform a blood test for Epstein-Barr virus (EBV) viral serology after at least 7 days of illness. However, for immunocompetent adults and children older than 12, a FBC with differential white cell count and a monospot test (heterophile antibodies) should be conducted during the second week of the illness.
Further Reading:
Glandular fever, also known as infectious mononucleosis or mono, is a clinical syndrome characterized by symptoms such as sore throat, fever, and swollen lymph nodes. It is primarily caused by the Epstein-Barr virus (EBV), with other viruses and infections accounting for the remaining cases. Glandular fever is transmitted through infected saliva and primarily affects adolescents and young adults. The incubation period is 4-8 weeks.
The majority of EBV infections are asymptomatic, with over 95% of adults worldwide having evidence of prior infection. Clinical features of glandular fever include fever, sore throat, exudative tonsillitis, lymphadenopathy, and prodromal symptoms such as fatigue and headache. Splenomegaly (enlarged spleen) and hepatomegaly (enlarged liver) may also be present, and a non-pruritic macular rash can sometimes occur.
Glandular fever can lead to complications such as splenic rupture, which increases the risk of rupture in the spleen. Approximately 50% of splenic ruptures associated with glandular fever are spontaneous, while the other 50% follow trauma. Diagnosis of glandular fever involves various investigations, including viral serology for EBV, monospot test, and liver function tests. Additional serology tests may be conducted if EBV testing is negative.
Management of glandular fever involves supportive care and symptomatic relief with simple analgesia. Antiviral medication has not been shown to be beneficial. It is important to identify patients at risk of serious complications, such as airway obstruction, splenic rupture, and dehydration, and provide appropriate management. Patients can be advised to return to normal activities as soon as possible, avoiding heavy lifting and contact sports for the first month to reduce the risk of splenic rupture.
Rare but serious complications associated with glandular fever include hepatitis, upper airway obstruction, cardiac complications, renal complications, neurological complications, haematological complications, chronic fatigue, and an increased risk of lymphoproliferative cancers and multiple sclerosis.
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This question is part of the following fields:
- Infectious Diseases
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Question 11
Incorrect
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A 45-year-old woman who is originally from Brazil has recently developed dilated cardiomyopathy and difficulty swallowing. She remembers being bitten by an insect approximately 10 years ago, which resulted in a fever and flu-like symptoms. On her ankle, where the bite occurred, she now has a firm, violet-colored lump.
What is the SINGLE most probable diagnosis?Your Answer:
Correct Answer: Chagas disease
Explanation:Chagas disease, also known as American Trypanosomiasis, is a tropical illness caused by the protozoan Trypanosoma cruzi. It is transmitted by Triatomine insects, commonly known as kissing bugs, which belong to the Reduviidae family. This zoonotic disease is prevalent in Central and South America, with an estimated 8 million people infected in the region. In Brazil alone, there are approximately 120,000 new cases reported each year.
The disease progresses through two stages: the acute stage and the chronic stage. During the acute stage, many patients may not experience any symptoms, and the infection can go unnoticed. However, some individuals may exhibit symptoms such as fever, malaise, muscle pain, loss of appetite, and occasionally vomiting and diarrhea. Clinical signs may include swollen lymph nodes and enlargement of the liver and spleen. At the site of the insect bite, an inflammatory response called a chagoma can occur. This is characterized by a swollen, violet-colored nodule that can last up to 8 weeks. Another distinctive sign of acute Chagas disease is Romaña’s sign, which is eyelid swelling caused by accidentally rubbing bug feces into the eyes.
Following the acute stage, an estimated 10-30% of individuals progress to the chronic stage of Chagas disease. There is typically a latent phase between the acute and chronic phases, which can last for as long as 20-30 years. The chronic phase is associated with various complications, including cardiovascular problems such as dilated cardiomyopathy, heart failure, and arrhythmias. Gastrointestinal issues like megacolon, megaesophagus, and secondary achalasia can also arise. Neurological complications, such as neuritis, sensory and motor deficits, and encephalopathy, may occur. Additionally, psychiatric symptoms, including dementia, can manifest in some cases.
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This question is part of the following fields:
- Infectious Diseases
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Question 12
Incorrect
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A 35 year old male comes to the emergency department after being bitten by a stray dog. The patient has three small puncture wounds and mentions slight bleeding from both puncture wounds after the initial bite that ceased after applying pressure for 10 minutes. The patient inquires about the necessity of antibiotics. What is the most suitable reply?
Your Answer:
Correct Answer: Issue a prescription for a 3 day course of co-amoxiclav
Explanation:It is recommended to administer prophylactic oral antibiotics to individuals who have experienced a cat bite that has broken the skin and cause bleeding. For patients over one month of age, co-amoxiclav should be prescribed for a duration of 3 days. In cases where the patient is allergic to penicillin, a combination of metronidazole and doxycycline should be given for 3 days. If the wound shows signs of infection, the antibiotic treatment should be extended to 5 days.
Prophylactic oral antibiotics may also be considered for individuals with a cat bite that has broken the skin but has not caused bleeding, especially if the wound is deep.
Debridement, the removal of dead tissue, should be considered for wounds that are damaged, have abscess formation, lymphangitis, severe cellulitis, osteomyelitis, septic arthritis, necrotising fasciitis, or infected bite wounds that are not responding to treatment. Additionally, individuals who are systemically unwell should also undergo debridement.
Antibiotics should also be considered for other animal bites, such as dog bites, that have broken the skin and cause bleeding.
Further Reading:
Bite wounds from animals and humans can cause significant injury and infection. It is important to properly assess and manage these wounds to prevent complications. In human bites, both the biter and the injured person are at risk of infection transmission, although the risk is generally low.
Bite wounds can take various forms, including lacerations, abrasions, puncture wounds, avulsions, and crush or degloving injuries. The most common mammalian bites are associated with dogs, cats, and humans.
When assessing a human bite, it is important to gather information about how and when the bite occurred, who was involved, whether the skin was broken or blood was involved, and the nature of the bite. The examination should include vital sign monitoring if the bite is particularly traumatic or sepsis is suspected. The location, size, and depth of the wound should be documented, along with any functional loss or signs of infection. It is also important to check for the presence of foreign bodies in the wound.
Factors that increase the risk of infection in bite wounds include the nature of the bite, high-risk sites of injury (such as the hands, feet, face, genitals, or areas of poor perfusion), wounds penetrating bone or joints, delayed presentation, immunocompromised patients, and extremes of age.
The management of bite wounds involves wound care, assessment and administration of prophylactic antibiotics if indicated, assessment and administration of tetanus prophylaxis if indicated, and assessment and administration of antiviral prophylaxis if indicated. For initial wound management, any foreign bodies should be removed, the wound should be encouraged to bleed if fresh, and thorough irrigation with warm, running water or normal saline should be performed. Debridement of necrotic tissue may be necessary. Bite wounds are usually not appropriate for primary closure.
Prophylactic antibiotics should be considered for human bites that have broken the skin and drawn blood, especially if they involve high-risk areas or the patient is immunocompromised. Co-amoxiclav is the first-line choice for prophylaxis, but alternative antibiotics may be used in penicillin-allergic patients. Antibiotics for wound infection should be based on wound swab culture and sensitivities.
Tetanus prophylaxis should be administered based on the cleanliness and risk level of the wound, as well as the patient’s vaccination status. Blood-borne virus risk should also be assessed, and testing for hepatitis B, hepatitis C, and HIV should be done.
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This question is part of the following fields:
- Infectious Diseases
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Question 13
Incorrect
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You receive a needlestick injury after drawing blood from a 45-year-old patient. The patient is visiting due to experiencing frequent heart palpitations. Her only significant medical history is hypothyroidism, for which she is prescribed thyroxine.
What should be your initial course of action in this situation?Your Answer:
Correct Answer: Wash the wound with soap and water and gently encourage bleeding
Explanation:First and foremost, the immediate concern is providing first aid for the wound. It is important to wash the wound with soap (or chlorhexidine) and water, while gently encouraging bleeding. It is crucial not to scrub or suck the wound. Additionally, if there are any splashes or body fluid that come into contact with the eyes or mouth, they should be thoroughly washed.
For all healthcare workers who experience a needlestick injury, it is necessary to have a baseline serum sample taken and stored. This should be arranged through occupational health. The subsequent management of the injury depends on the risk of blood-borne virus transmission. This risk is determined by factors such as the source patient’s history (e.g. IV drug use), the circumstances of the injury (e.g. visible blood on the device, use of personal protection equipment), and the healthcare worker’s own characteristics (e.g. response to hepatitis B vaccination).
If the patient consents after appropriate counseling, blood may be taken from the source patient for blood-borne virus testing. However, it is important to note that the injured healthcare worker should not be responsible for counseling and obtaining consent from the patient. Lastly, all needlestick injuries should be reported to the Health Protection Agency.
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This question is part of the following fields:
- Infectious Diseases
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Question 14
Incorrect
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A 25-year-old traveler returns from a recent trip to Northern India with frequent headaches and occasional fevers. She describes experiencing intense chills, followed by feeling hot and then sweating profusely.
During examination, she appears drowsy and has a temperature of 38.9°C. There are no noticeable swollen lymph nodes or rash, but upon examining her abdomen, hepatosplenomegaly is observed.
Today's blood tests reveal the following results:
- Sodium (Na): 140 mmol/L (135-147 mmol/L)
- Potassium (K): 4.9 mmol/L (3.5-5.5 mmol/L)
- Urea: 11.5 mmol/L (2.0-6.6 mmol/L)
- Creatinine: 268 mmol/L (75-125 mmol/L)
What is the SINGLE most likely diagnosis?Your Answer:
Correct Answer: Malaria
Explanation:Malaria is a contagious illness that is spread by female mosquitoes of the Anopheles genus. It is caused by a parasitic infection from the Plasmodium genus. There are five species of Plasmodium that can cause disease in humans: Plasmodium falciparum, Plasmodium ovale, Plasmodium vivax, Plasmodium malariae, and Plasmodium knowlesi.
The main symptom of malaria is the malarial paroxysm, which is a recurring cycle of cold, hot, and sweating stages. During the cold stage, the patient experiences intense chills, followed by an extremely hot stage, and finally a stage of profuse sweating. Upon examination, the patient may show signs of anemia, jaundice, and have an enlarged liver and spleen, but no signs of swollen lymph nodes.
Plasmodium falciparum is the most severe form of malaria and is responsible for the majority of deaths. Severe or complicated malaria is indicated by impaired consciousness, seizures, low blood sugar, anemia, kidney damage, difficulty breathing, and spontaneous bleeding. Given the presentation, it is likely that this case involves Plasmodium falciparum.
Currently, artemisinin-based combination therapy (ACT) is recommended for treating P. falciparum malaria. This involves combining fast-acting artemisinin-based compounds with a drug from a different class. Companion drugs include lumefantrine, mefloquine, amodiaquine, sulfadoxine/pyrimethamine, piperaquine, and chlorproguanil/dapsone. Artemisinin derivatives include dihydroartemisinin, artesunate, and artemether.
If ACT is not available, oral quinine or atovaquone with proguanil hydrochloride can be used. Quinine is highly effective but not well tolerated for long-term treatment, so it should be combined with another drug, usually oral doxycycline (or clindamycin for pregnant women and young children).
Severe or complicated falciparum malaria should be managed in a high dependency unit or intensive care setting. Intravenous artesunate is recommended for all patients with severe or complicated falciparum malaria, or those at high risk of developing severe disease (such as if more than 2% of red blood cells are infected), or
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This question is part of the following fields:
- Infectious Diseases
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Question 15
Incorrect
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A patient with a past medical history of epigastric discomfort and diarrhea is diagnosed with a tapeworm infection. The infection was acquired after consuming a beef dish that was contaminated with the parasite.
Which of the following organisms is most likely responsible for causing this infestation?Your Answer:
Correct Answer: Taenia saginata
Explanation:Two types of tapeworms, Taenia solium and Taenia saginata, can infest humans. Infestation occurs when people consume meat from intermediate hosts that contain the parasite’s tissue stages. Tapeworms compete for nutrients and infestation is often without symptoms. However, in more severe cases, individuals may experience epigastric pain, diarrhea, and vomiting. Diagnosis involves identifying characteristic eggs in the patient’s stool.
Taenia solium infestation can also lead to a condition called cysticercosis. This occurs when larval cysts infiltrate and spread throughout the lung, liver, eye, or brain. Cysticercosis presents with neurological symptoms, seizures, and impaired vision. Confirmation of cysticercosis involves the presence of antibodies and imaging tests such as chest X-rays and CT brain scans.
The treatment for tapeworm infestation is highly effective and involves the use of medications like niclosamide or praziquantel. However, it is important to seek specialist advice when managing Taenia infections in the central nervous system, as severe inflammatory reactions can occur.
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This question is part of the following fields:
- Infectious Diseases
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Question 16
Incorrect
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A 35-year-old individual presents to the emergency department complaining of progressive weakness and numbness over the past few days. The patient reports initially experiencing numbness in both feet, which has gradually extended up to the knees. Additionally, there is weakness in both legs and numbness in the fingertips that appeared earlier today. The patient has no regular medication and is generally in good health. However, about three weeks ago, during a trip to India, the patient suffered from a week-long illness characterized by watery, occasionally bloody, diarrhea and abdominal cramps, which have completely resolved. What is the most likely causative organism?
Your Answer:
Correct Answer: Campylobacter jejuni
Explanation:This explanation suggests that the patient’s symptoms are consistent with a case of travellers diarrhoea, which is in line with their medical history. GBS typically occurs within 1-3 weeks after the initial viral or bacterial infection that caused it.
Further Reading:
Campylobacter jejuni is a common cause of gastrointestinal infections, particularly travellers diarrhoea. It is a gram-negative bacterium that appears as curved rods. The infection is transmitted through the feco-oral route, often through the ingestion of contaminated meat, especially poultry. The incubation period for Campylobacter jejuni is typically 1-7 days, and the illness usually lasts for about a week.
The main symptoms of Campylobacter jejuni infection include watery, and sometimes bloody, diarrhea accompanied by abdominal cramps, fever, malaise, and headache. In some cases, complications can arise from the infection. Guillain-Barre syndrome (GBS) is one such complication that is associated with Campylobacter jejuni. Approximately 30% of GBS cases are caused by this bacterium.
When managing Campylobacter jejuni infection, conservative measures are usually sufficient, with a focus on maintaining hydration. However, in cases where symptoms are severe, such as high fever, bloody diarrhea, or high-output diarrhea, or if the person is immunocompromised, antibiotics may be necessary. NICE recommends the use of clarithromycin, administered at a dose of 250-500 mg twice daily for 5-7 days, starting within 3 days of the onset of illness.
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This question is part of the following fields:
- Infectious Diseases
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Question 17
Incorrect
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A young toddler is brought in by his father with a high temperature at home. The triage nurse measures his temperature again as part of her initial evaluation.
Which SINGLE statement regarding temperature measurement in young children is accurate?Your Answer:
Correct Answer: The rectal route should not be used to measure temperature
Explanation:Reported parental perception of a fever should be regarded as valid and taken seriously by healthcare professionals.
For infants under the age of 4 weeks, it is recommended to measure body temperature using an electronic thermometer in the axilla.
In children aged 4 weeks to 5 years, body temperature can be measured using one of the following methods: an electronic thermometer in the axilla, a chemical dot thermometer in the axilla, or an infra-red tympanic thermometer.
It is important to note that oral and rectal routes should not be utilized for temperature measurement in this age group. Additionally, forehead chemical thermometers are not reliable and should be avoided.
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This question is part of the following fields:
- Infectious Diseases
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Question 18
Incorrect
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A 25-year-old woman presents with a 5-day history of a painful throat, high temperature, diarrhea, and muscle aches. Her temperature today is 38.6°C. Approximately 8 months ago, she began misusing intravenous drugs and acknowledges sharing needles. During the examination, you confirm the existence of lymph node swelling in the neck and armpits. Additionally, she has developed a widespread rash consisting of small raised bumps on her chest and abdomen.
Select from the options below the most probable diagnosis.Your Answer:
Correct Answer: HIV seroconversion illness
Explanation:This man is at high risk of contracting HIV due to his history of intravenous drug abuse and sharing needles. If a patient has a flu-like illness and a history of risk factors, it is important to suspect that they may be experiencing an HIV seroconversion illness.
Around 20-60% of individuals who contract HIV go through a seroconversion illness. This typically occurs within 1 to 6 weeks after exposure and presents with symptoms similar to the flu. Common clinical features include fever, malaise, myalgia, pharyngitis, diarrhea, headaches, maculopapular rash, lymphadenopathy, and neuralgia.
During this stage of the disease, antibody tests will show negative results. However, a diagnosis of HIV can still be made by conducting a P24 antigen test or measuring HIV RNA levels. CD4 and CD8 counts are usually within the normal range at this stage.
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This question is part of the following fields:
- Infectious Diseases
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Question 19
Incorrect
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You evaluate a 30-year-old woman with a confirmed diagnosis of HIV. She inquires about her diagnosis and has some questions for you.
Choose from the options provided below the ONE CD4 count that indicates advanced HIV disease (also referred to as AIDS).Your Answer:
Correct Answer: 200 cells/mm3
Explanation:A normal CD4 count ranges from 500-1000 cells/mm3. In individuals diagnosed with HIV, the CD4 count is typically monitored every 3-6 months. It is important to note that the CD4 count can fluctuate on a daily basis and can be influenced by the timing of the blood test as well as the presence of other infections or illnesses.
When the CD4 count falls below 350 cells/mm3, it is recommended to consider starting antiretroviral therapy. A CD4 count below 200 cells/mm3 is indicative of advanced HIV disease, also known as AIDS defining.
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This question is part of the following fields:
- Infectious Diseases
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Question 20
Incorrect
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You are asked to evaluate a 7-year-old boy who has arrived at the emergency department with a widespread maculopapular rash. The patient and his family have recently returned from a trip to Mexico. The mother is uncertain about the vaccinations the patient has received, and you have no access to medical records as the family relocated to the US from Mexico 8 months ago and have not yet registered with a primary care physician. You suspect Measles. What guidance should you provide to the patient's mother regarding school attendance?
Your Answer:
Correct Answer: Exclude for 5 days from onset of rash
Explanation:Children who have been diagnosed with Rubella, also known as German measles, should be advised to stay away from school for a period of 5 days from the onset of the rash. It is important to be familiar with the guidelines for excluding children from school due to infectious diseases that present with a rash.
Further Reading:
Rubella, also known as German measles, is a viral infection caused by the togavirus. It used to be more common before the introduction of the MMR vaccine, but now it is rare. Outbreaks of rubella are more common during the winter and spring seasons. The incubation period for rubella is 14-21 days, and individuals are infectious from 7 days before symptoms appear to 4-5 days after the onset of the rash.
The features of rubella include a prodrome, which may include symptoms such as low-grade fever. The rash associated with rubella is maculopapular and initially appears on the face before spreading to the whole body. The rash usually fades by the 3-5 day. Lymphadenopathy, specifically suboccipital and postauricular, is also commonly seen in rubella cases.
Complications of rubella can include arthritis, thrombocytopenia, encephalitis, and myocarditis. However, these complications are rare. Rubella can be particularly dangerous if contracted during pregnancy, as it can lead to congenital rubella syndrome. The risk of fetal damage is highest during the first 8-10 weeks of pregnancy, with a risk as high as 90%. Fetal damage is rare after 16 weeks. Congenital rubella syndrome can result in various complications such as sensorineural deafness, congenital cataracts, congenital heart disease, growth retardation, hepatosplenomegaly, purpuric skin lesions, ‘salt and pepper’ chorioretinitis, microphthalmia, and cerebral palsy.
Diagnosis of rubella can be made by testing for raised IgM antibodies in women who have recently been exposed to the virus. Serological or PCR testing is the gold standard investigation for rubella. A testing kit can be obtained from the Local Health Protection Unit (HPU).
There is no specific treatment for rubella. Antipyretics can be used to manage fever. It is advised to exclude individuals with rubella from school for 5 days from the onset of the rash. Infection during pregnancy should prompt referral to obstetrics. Rubella is a notifiable disease, meaning that it requires notification of the local authority or UKHSA health protection team.
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This question is part of the following fields:
- Infectious Diseases
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Question 21
Incorrect
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A 28-year-old medical student has experienced a needlestick injury while working in the Emergency Department.
Select from the list of options below the single correct seroconversion rate for the specified pathogen.Your Answer:
Correct Answer: 0.3% for percutaneous exposure to HIV-infected blood
Explanation:The estimated rates of seroconversion are provided below:
– Percutaneous exposure of a non-immune individual to an HBeAg positive contact results in a seroconversion rate of approximately 30%.
– When exposed to HCV-infected blood with detectable RNA through percutaneous means, the seroconversion rate ranges from 0.5% to 1.8%.
– Mucocutaneous exposure to HIV-infected blood leads to a seroconversion rate of 0.1%.
– Lastly, percutaneous exposure to HIV-infected blood results in a seroconversion rate of 0.3%.
Please note that these rates are estimates and may vary depending on individual circumstances.
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This question is part of the following fields:
- Infectious Diseases
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Question 22
Incorrect
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A 70-year-old patient arrives at the emergency department complaining of fever, fatigue, and loss of appetite for the past 3 weeks. During the examination, you observe a pansystolic murmur that was not detected during a pre-operative assessment for a cholecystectomy 4 months ago. You start considering the likelihood of infective endocarditis. Which of the following symptoms is commonly associated with infective endocarditis?
Your Answer:
Correct Answer: Janeway lesions
Explanation:Infective endocarditis is a condition that can be identified by certain signs, although none of them are definitive proof of the disease. The most reliable indicators are the presence of a heart murmur and a fever. However, there are other signs that are commonly associated with infective endocarditis, including splinter hemorrhages, Osler’s nodes, Janeway lesions, and Roth spots. It is important to note that these signs can also appear in other conditions, and they are not always present in patients with infective endocarditis. In fact, each of these signs is typically found in less than a third of patients diagnosed with the disease.
Further Reading:
Infective endocarditis (IE) is an infection that affects the innermost layer of the heart, known as the endocardium. It is most commonly caused by bacteria, although it can also be caused by fungi or viruses. IE can be classified as acute, subacute, or chronic depending on the duration of illness. Risk factors for IE include IV drug use, valvular heart disease, prosthetic valves, structural congenital heart disease, previous episodes of IE, hypertrophic cardiomyopathy, immune suppression, chronic inflammatory conditions, and poor dental hygiene.
The epidemiology of IE has changed in recent years, with Staphylococcus aureus now being the most common causative organism in most industrialized countries. Other common organisms include coagulase-negative staphylococci, streptococci, and enterococci. The distribution of causative organisms varies depending on whether the patient has a native valve, prosthetic valve, or is an IV drug user.
Clinical features of IE include fever, heart murmurs (most commonly aortic regurgitation), non-specific constitutional symptoms, petechiae, splinter hemorrhages, Osler’s nodes, Janeway’s lesions, Roth’s spots, arthritis, splenomegaly, meningism/meningitis, stroke symptoms, and pleuritic pain.
The diagnosis of IE is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Major criteria include positive blood cultures with typical microorganisms and positive echocardiogram findings. Minor criteria include fever, vascular phenomena, immunological phenomena, and microbiological phenomena. Blood culture and echocardiography are key tests for diagnosing IE.
In summary, infective endocarditis is an infection of the innermost layer of the heart that is most commonly caused by bacteria. It can be classified as acute, subacute, or chronic and can be caused by a variety of risk factors. Staphylococcus aureus is now the most common causative organism in most industrialized countries. Clinical features include fever, heart murmurs, and various other symptoms. The diagnosis is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Blood culture and echocardiography are important tests for diagnosing IE.
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This question is part of the following fields:
- Infectious Diseases
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Question 23
Incorrect
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A 28 year old IV drug user comes to the emergency department with complaints of feeling sick. Considering the history of IV drug abuse, there is concern for infective endocarditis. Which structure is most likely to be impacted in this individual?
Your Answer:
Correct Answer: Tricuspid valve
Explanation:The tricuspid valve is the most commonly affected valve in cases of infective endocarditis among intravenous drug users. This means that when IV drug users develop infective endocarditis, it is most likely to affect the tricuspid valve. On the other hand, in cases of native valve endocarditis and prosthetic valve endocarditis, the mitral valve is the valve that is most commonly affected.
Further Reading:
Infective endocarditis (IE) is an infection that affects the innermost layer of the heart, known as the endocardium. It is most commonly caused by bacteria, although it can also be caused by fungi or viruses. IE can be classified as acute, subacute, or chronic depending on the duration of illness. Risk factors for IE include IV drug use, valvular heart disease, prosthetic valves, structural congenital heart disease, previous episodes of IE, hypertrophic cardiomyopathy, immune suppression, chronic inflammatory conditions, and poor dental hygiene.
The epidemiology of IE has changed in recent years, with Staphylococcus aureus now being the most common causative organism in most industrialized countries. Other common organisms include coagulase-negative staphylococci, streptococci, and enterococci. The distribution of causative organisms varies depending on whether the patient has a native valve, prosthetic valve, or is an IV drug user.
Clinical features of IE include fever, heart murmurs (most commonly aortic regurgitation), non-specific constitutional symptoms, petechiae, splinter hemorrhages, Osler’s nodes, Janeway’s lesions, Roth’s spots, arthritis, splenomegaly, meningism/meningitis, stroke symptoms, and pleuritic pain.
The diagnosis of IE is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Major criteria include positive blood cultures with typical microorganisms and positive echocardiogram findings. Minor criteria include fever, vascular phenomena, immunological phenomena, and microbiological phenomena. Blood culture and echocardiography are key tests for diagnosing IE.
In summary, infective endocarditis is an infection of the innermost layer of the heart that is most commonly caused by bacteria. It can be classified as acute, subacute, or chronic and can be caused by a variety of risk factors. Staphylococcus aureus is now the most common causative organism in most industrialized countries. Clinical features include fever, heart murmurs, and various other symptoms. The diagnosis is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Blood culture and echocardiography are important tests for diagnosing IE.
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This question is part of the following fields:
- Infectious Diseases
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Question 24
Incorrect
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A 25-year-old engineering student returns from a hiking trip in South America with a high temperature, body pains, and shivering. After further examination, they are diagnosed with malaria.
Which of the following statements about malaria is correct?Your Answer:
Correct Answer: Haemoglobinuria and renal failure following treatment is suggestive of Plasmodium falciparum
Explanation:Plasmodium ovale has the longest incubation period, which can extend up to 40 days. On the other hand, Plasmodium falciparum has a shorter incubation period of 7-14 days. The transmission of malaria occurs through the female mosquitoes belonging to the Anopheles genus.
Blackwater fever, which is caused by Plasmodium falciparum, can be indicated by the presence of haemoglobinuria and renal failure following treatment. This condition is a result of an autoimmune reaction between the parasite and quinine, leading to haemolysis, haemoglobinuria, jaundice, and renal failure. It is a potentially fatal complication. The diagnosis of malaria is typically done using the Indirect Fluorescence Antibody Test (IFAT).
Currently, the recommended treatment for P. falciparum malaria is artemisinin-based combination therapy (ACT). This involves combining fast-acting artemisinin-based compounds with a drug from a different class. Some companion drugs used in ACT include lumefantrine, mefloquine, amodiaquine, sulfadoxine/pyrimethamine, piperaquine, and chlorproguanil/dapsone. Artemisinin derivatives such as dihydroartemisinin, artesunate, and artemether are also used.
In cases where artemisinin combination therapy is not available, oral quinine or atovaquone with proguanil hydrochloride can be used as an alternative. However, quinine is highly effective but not well-tolerated in prolonged treatment, so it is usually combined with another drug, typically oral doxycycline (or clindamycin in pregnant women and young children).
Severe or complicated falciparum malaria requires management in a high dependency unit or intensive care setting. Intravenous artesunate is recommended for all patients with severe or complicated falciparum malaria, or those at high risk of developing severe disease (e.g., if more than 2% of red blood cells are parasitized), or if the patient is unable to take oral treatment. After a minimum of 24 hours of intravenous artesunate treatment and improvement in the patient’s condition, a full course of artemisinin combination therapy should be administered orally.
The benign malarias, namely P. vivax, P. malariae, and P. ovale,
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This question is part of the following fields:
- Infectious Diseases
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Question 25
Incorrect
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A 25-year-old engineering student returns from a hiking trip in South America with a high temperature, body aches, and shivering. After further examination, they are diagnosed with Plasmodium falciparum malaria.
Which of the following statements about Plasmodium falciparum malaria is NOT true?Your Answer:
Correct Answer: It is commonly the result of travel in the Indian subcontinent
Explanation:Plasmodium falciparum malaria is transmitted by female mosquitoes of the Anopheles genus. While it can be found worldwide, it is most prevalent in Africa. The incubation period for this type of malaria is typically between 7 to 14 days.
The parasite, known as sporozoites, invades hepatocytes (liver cells). Inside the hepatocyte, the parasite undergoes asexual reproduction, resulting in the production of merozoites. These merozoites are then released into the bloodstream and invade the red blood cells of the host.
Currently, the recommended treatment for P. falciparum malaria is artemisinin-based combination therapy (ACT). This involves combining fast-acting artemisinin-based compounds with drugs from different classes. Some of the companion drugs used in ACT include lumefantrine, mefloquine, amodiaquine, sulfadoxine/pyrimethamine, piperaquine, and chlorproguanil/dapsone. Artemisinin derivatives such as dihydroartemisinin, artesunate, and artemether are also used.
In cases where artemisinin combination therapy is not available, oral quinine or atovaquone with proguanil hydrochloride can be used as alternatives. However, quinine is not well-tolerated for prolonged treatment and should be combined with another drug, typically oral doxycycline (or clindamycin for pregnant women and young children).
For severe or complicated cases of falciparum malaria, it is recommended to manage the patient in a high dependency unit or intensive care setting. Intravenous artesunate is indicated for all patients with severe or complicated falciparum malaria, as well as those at high risk of developing severe disease (e.g., if more than 2% of red blood cells are parasitized) or if the patient is unable to take oral treatment. After a minimum of 24 hours of intravenous artesunate treatment and once the patient has shown improvement and can tolerate oral treatment, a full course of artemisinin combination therapy should be administered.
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This question is part of the following fields:
- Infectious Diseases
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Question 26
Incorrect
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A 35 year old female presents to the emergency department complaining of loose watery stools, abdominal cramps, and intermittent vomiting for the past 48 hours. The patient mentions that several of her coworkers have been absent from work due to a stomach virus. Based on these symptoms and history, what is the most probable causative organism for this patient's condition?
Your Answer:
Correct Answer: Norovirus
Explanation:Norovirus is the leading cause of gastroenteritis in adults in the UK. Viruses are responsible for the majority of cases of infectious diarrhea, with norovirus being the most common culprit in adults. Among young children, rotavirus is the primary pathogen, although its prevalence has decreased since the introduction of a rotavirus vaccine. As of 2023, rotavirus remains the most common cause of viral gastroenteritis in children.
Further Reading:
Gastroenteritis is a transient disorder characterized by the sudden onset of diarrhea, with or without vomiting. It is caused by enteric infections with viruses, bacteria, or parasites. The most common viral causes of gastroenteritis in adults include norovirus, rotavirus, and adenovirus. Bacterial pathogens such as Campylobacter jejuni and coli, Escherichia coli, Clostridium perfringens, Bacillus cereus, Staphylococcus aureus, Salmonella typhi and paratyphi, and Shigella dysenteriae, flexneri, boydii, and sonnei can also cause gastroenteritis. Parasites such as Cryptosporidium, Entamoeba histolytica, and Giardia intestinalis or Giardia lamblia can also lead to diarrhea.
Diagnosis of gastroenteritis is usually based on clinical symptoms, and investigations are not required in many cases. However, stool culture may be indicated in certain situations, such as when the patient is systemically unwell or immunocompromised, has acute painful diarrhea or blood in the stool suggesting dysentery, has recently taken antibiotics or acid-suppressing medications, or has not resolved diarrhea by day 7 or has recurrent diarrhea.
Management of gastroenteritis in adults typically involves advice on oral rehydration. Intravenous rehydration and more intensive treatment may be necessary for patients who are systemically unwell, exhibit severe dehydration, or have intractable vomiting or high-output diarrhea. Antibiotics are not routinely required unless a specific organism is identified that requires treatment. Antidiarrheal drugs, antiemetics, and probiotics are not routinely recommended.
Complications of gastroenteritis can occur, particularly in young children, the elderly, pregnant women, and immunocompromised individuals. These complications include dehydration, electrolyte disturbance, acute kidney injury, haemorrhagic colitis, haemolytic uraemic syndrome, reactive arthritis, Reiter’s syndrome, aortitis, osteomyelitis, sepsis, toxic megacolon, pancreatitis, sclerosing cholangitis, liver cirrhosis, weight loss, chronic diarrhea, irritable bowel syndrome, inflammatory bowel disease, acquired lactose intolerance, Guillain-Barré syndrome, meningitis, invasive entamoeba infection, and liver abscesses.
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This question is part of the following fields:
- Infectious Diseases
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Question 27
Incorrect
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A 25-year-old type 1 diabetic arrives at the emergency department complaining of a worsening sore throat, fever, and overall feeling of illness. The patient reports that the symptoms began a week ago. During the examination, the patient's temperature is measured at 38.3ºC, bilateral posterior cervical lymphadenopathy is observed, and there is exudate on both tonsils. Additionally, tenderness is noted in the right upper quadrant. Glandular fever is suspected.
What would be the most suitable approach for conducting further investigations?Your Answer:
Correct Answer: Send blood for Epstein-Barr virus (EBV) viral serology
Explanation:Glandular fever, also known as infectious mononucleosis or mono, is a clinical syndrome characterized by symptoms such as sore throat, fever, and swollen lymph nodes. It is primarily caused by the Epstein-Barr virus (EBV), with other viruses and infections accounting for the remaining cases. Glandular fever is transmitted through infected saliva and primarily affects adolescents and young adults. The incubation period is 4-8 weeks.
The majority of EBV infections are asymptomatic, with over 95% of adults worldwide having evidence of prior infection. Clinical features of glandular fever include fever, sore throat, exudative tonsillitis, lymphadenopathy, and prodromal symptoms such as fatigue and headache. Splenomegaly (enlarged spleen) and hepatomegaly (enlarged liver) may also be present, and a non-pruritic macular rash can sometimes occur.
Glandular fever can lead to complications such as splenic rupture, which increases the risk of rupture in the spleen. Approximately 50% of splenic ruptures associated with glandular fever are spontaneous, while the other 50% follow trauma. Diagnosis of glandular fever involves various investigations, including viral serology for EBV, monospot test, and liver function tests. Additional serology tests may be conducted if EBV testing is negative.
Management of glandular fever involves supportive care and symptomatic relief with simple analgesia. Antiviral medication has not been shown to be beneficial. It is important to identify patients at risk of serious complications, such as airway obstruction, splenic rupture, and dehydration, and provide appropriate management. Patients can be advised to return to normal activities as soon as possible, avoiding heavy lifting and contact sports for the first month to reduce the risk of splenic rupture.
Rare but serious complications associated with glandular fever include hepatitis, upper airway obstruction, cardiac complications, renal complications, neurological complications, haematological complications, chronic fatigue, and an increased risk of lymphoproliferative cancers and multiple sclerosis.
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This question is part of the following fields:
- Infectious Diseases
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Question 28
Incorrect
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A 25-year-old engineering student returns from a hiking trip in South America with a high temperature, body aches, and shivering. After further examination, they are diagnosed with Plasmodium falciparum malaria.
Which of the following statements about Plasmodium falciparum malaria is correct?Your Answer:
Correct Answer: There may be a continuous fever
Explanation:Plasmodium falciparum malaria is transmitted by female mosquitoes of the Anopheles genus. The Aedes genus, on the other hand, is responsible for spreading diseases like dengue fever and yellow fever. The parasite enters hepatocytes and undergoes asexual reproduction, resulting in the release of merozoites into the bloodstream. These merozoites then invade the red blood cells of the host. The incubation period for Plasmodium falciparum malaria ranges from 7 to 14 days.
The main symptom of malaria is known as the malarial paroxysm, which consists of a cyclical pattern of cold chills, followed by a stage of intense heat, and finally a period of profuse sweating as the fever subsides. However, some individuals may experience a continuous fever instead.
Currently, the recommended treatment for P. falciparum malaria is artemisinin-based combination therapy (ACT). This involves combining fast-acting artemisinin-based compounds with drugs from a different class. Companion drugs used in ACT include lumefantrine, mefloquine, amodiaquine, sulfadoxine/pyrimethamine, piperaquine, and chlorproguanil/dapsone. Artemisinin derivatives such as dihydroartemisinin, artesunate, and artemether are also used.
If artemisinin combination therapy is not available, oral quinine or atovaquone with proguanil hydrochloride can be used as an alternative. However, quinine is not well-tolerated for prolonged treatment and should be combined with another drug, typically oral doxycycline (or clindamycin for pregnant women and young children).
Severe or complicated cases of falciparum malaria require specialized care in a high dependency unit or intensive care setting. Intravenous artesunate is recommended for all patients with severe or complicated falciparum malaria, as well as those at high risk of developing severe disease (e.g., if more than 2% of red blood cells are parasitized) or if the patient is unable to take oral treatment. After a minimum of 24 hours of intravenous artesunate treatment and improvement in the patient’s condition, a full course of artemisinin combination therapy should be administered orally.
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This question is part of the following fields:
- Infectious Diseases
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Question 29
Incorrect
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A child with a history of stomach pain and loose stools is diagnosed with a tapeworm infection after finding eggs in their stool.
What is the most suitable treatment for this infection?Your Answer:
Correct Answer: Praziquantel
Explanation:Two types of tapeworms, Taenia solium and Taenia saginata, can infest humans. Infestation occurs when people consume meat from intermediate hosts that contain the parasite’s tissue stages. Tapeworms compete for nutrients and infestation is often without symptoms. However, in more severe cases, individuals may experience epigastric pain, diarrhea, and vomiting. Diagnosis involves identifying characteristic eggs in the patient’s stool.
Taenia solium infestation can also lead to a condition called cysticercosis. This occurs when larval cysts infiltrate and spread throughout the lung, liver, eye, or brain. Cysticercosis presents with neurological symptoms, seizures, and impaired vision. Confirmation of cysticercosis involves the presence of antibodies and imaging tests such as chest X-rays and CT brain scans.
The treatment for tapeworm infestation is highly effective and involves the use of medications like niclosamide or praziquantel. However, it is important to seek specialist advice when managing Taenia infections in the central nervous system, as severe inflammatory reactions can occur.
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This question is part of the following fields:
- Infectious Diseases
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Question 30
Incorrect
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A 25-year-old individual comes in with a fever and symptoms resembling the flu. They also complain of muscle pain, diarrhea, and a dry cough. During the examination, their temperature is measured at 38.3°C and they exhibit tenderness in the upper right quadrant of their abdomen. Upon further inquiry, it is revealed that they recently returned from a backpacking trip to Malawi, where they recall developing blisters on their ankles after swimming in a lake. Blood tests indicate a significant increase in eosinophils.
What is the SINGLE most likely diagnosis?Your Answer:
Correct Answer: Schistosomiasis
Explanation:Schistosomiasis, also known as bilharzia, is a tropical disease caused by parasitic trematodes (flukes) of the Schistosoma type. The transmission of this disease occurs when water becomes contaminated with faeces or urine containing eggs, and a specific freshwater snail serves as the intermediate host. Human contact with water inhabited by the intermediate host snail is necessary for transmission to occur.
There are five species of Schistosoma that can cause human disease, namely S. japonicum, S. mansoni, S. haematobium, S. intercalatum, and S. mekongi. Schistosomiasis is the second most impactful tropical disease in terms of public health, following malaria, with over 200 million people worldwide being infected. It is prevalent in the Middle East, Africa, and parts of South America and the Caribbean. Infection can manifest as either acute or chronic.
Acute schistosomiasis is characterized by the early clinical sign of swimmers itch, which involves the development of blisters and an urticarial response at the site where the Schistosoma parasite enters the skin. This typically occurs a few days after the parasite has penetrated the skin. While most acute infections are asymptomatic, some individuals may experience an acute syndrome.
The most common acute syndrome is known as Katayama fever, which primarily affects children or young adults with no previous exposure to the disease. It is caused by an allergic reaction to the sudden release of highly antigenic eggs and usually occurs a few weeks after initial exposure to S. japonicum. Symptoms of Katayama fever include fever, flu-like illness, arthralgia, myalgia, abdominal pain, diarrhea, and cough. Patients may also exhibit right upper quadrant tenderness and hepatosplenomegaly. An extremely high eosinophil count is often present.
Chronic schistosomiasis can manifest in two major forms: intestinal and urogenital. Intestinal schistosomiasis is primarily caused by S. japonicum and S. mansoni, while S. haematobium is the main cause of urogenital schistosomiasis. In intestinal schistosomiasis, adult worms migrate from the liver to the mesenteric venules, where female worms continuously lay eggs. Common symptoms include abdominal pain and bloody diarrhea.
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This question is part of the following fields:
- Infectious Diseases
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