-
Question 1
Correct
-
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: 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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 2
Incorrect
-
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: Yellow fever
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 3
Correct
-
A 65 year old presents to the emergency department with a 3 week history of feeling generally fatigued. You observe that the patient has been undergoing yearly echocardiograms to monitor aortic stenosis. The patient informs you that he had a tooth extraction around 10 days prior to the onset of his symptoms. You suspect that infective endocarditis may be the cause. What organism is most likely responsible for this case?
Your Answer: Streptococcus viridans
Explanation:Based on the patient’s symptoms and medical history, the most likely organism responsible for this case of infective endocarditis is Streptococcus viridans. This is because the patient has a history of aortic stenosis, which is a risk factor for developing infective endocarditis. Additionally, the patient had a tooth extraction prior to the onset of symptoms, which can introduce bacteria into the bloodstream and increase the risk of infective endocarditis. Streptococcus viridans is a common cause of infective endocarditis, particularly in patients with underlying heart valve 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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 4
Incorrect
-
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: Tuberculosis
Correct 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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 5
Incorrect
-
You assess a 7-year-old girl who has been brought to the ER by her parents due to concerns about her health. They report that she has had a fever and a sore throat for the past few days, but now she has developed a red rash all over her body. After diagnosing scarlet fever, you prescribe antibiotics. What guidance would you provide to the parents regarding their child's attendance at school?
Your Answer: Exclusion from school until antibiotic course completed
Correct Answer: Exclusion from school until 24 hours after starting antibiotic treatment
Explanation:Patients who have been diagnosed with Scarlet fever should be instructed to stay away from school or work until at least 24 hours after they have started taking antibiotics. It is also important for them to practice good hygiene habits.
Further Reading:
Scarlet fever is a reaction to erythrogenic toxins produced by Group A haemolytic streptococci, usually Streptococcus pyogenes. It is more common in children aged 2-6 years, with the peak incidence at 4 years. The typical presentation of scarlet fever includes fever, malaise, sore throat (tonsillitis), and a rash. The rash appears 1-2 days after the fever and sore throat symptoms and consists of fine punctate erythema that first appears on the torso and spares the face. The rash has a rough ‘sandpaper’ texture and desquamation occurs later, particularly around the fingers and toes. Another characteristic feature is the ‘strawberry tongue’, which initially has a white coating and swollen, reddened papillae, and later becomes red and inflamed. Diagnosis is usually made by a throat swab, but antibiotic treatment should be started immediately without waiting for the results. The recommended treatment is oral penicillin V, but patients with a penicillin allergy should be given azithromycin. Children can return to school 24 hours after starting antibiotics. Scarlet fever is a notifiable disease. Complications of scarlet fever include otitis media, rheumatic fever, and acute glomerulonephritis.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 6
Correct
-
A patient who has recently come back from a journey to South America arrives with seizures and visual impairment. After conducting several tests, including a brain CT scan, the diagnosis of cysticercosis is established.
What is the most probable organism responsible for this condition?Your Answer: Taenia solium
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 7
Incorrect
-
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: Nasopharyngeal swab for PCR
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 8
Incorrect
-
A 32-year-old man is brought to the hospital with a known notifiable illness.
Which of the following is the LEAST probable diagnosis?Your Answer: Scarlet fever
Correct Answer: Leptospirosis
Explanation:Public Health England (PHE) has a primary goal of promptly identifying potential disease outbreaks and epidemics. While accuracy of diagnosis is important, it is not the main focus. 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 leptospirosis 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
-
-
Question 9
Correct
-
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 10
Correct
-
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 11
Incorrect
-
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: Arrange blood test for monospot heterophile antibodies in 7 -10 days
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 12
Correct
-
You evaluate a 32-year-old man with a previous history of intravenous drug use. He acknowledges sharing needles in the past. Currently, he presents with symptoms resembling the flu and a skin rash. You suspect that he might be going through an HIV seroconversion illness.
Choose from the following options the test that can provide the most accurate diagnosis of HIV during this stage.Your Answer: p24 antigen test
Explanation:ELISA and other antibody tests are highly sensitive methods for detecting the presence of HIV. However, they cannot be used in the early stages of the disease. There is usually a window period of 6-12 weeks before antibodies are produced, and these tests will yield negative results during a seroconversion illness.
The p24 antigen, which is the viral protein that forms the majority of the HIV core, is present in high concentrations in the first few weeks after infection. Therefore, the p24 antigen test is a valuable tool for diagnosing very early infections, such as those occurring during a seroconversion illness.
During the early stages of HIV infection, CD4 and CD8 counts are typically within the normal range and cannot be used for diagnosis in such cases.
The ‘rapid HIV test’ is an antibody test for HIV. Consequently, it will also yield negative results during the early ‘window period’. This test is referred to as ‘rapid’ because it can detect antibodies in blood or saliva much faster than other antibody tests, with results often available within 20 minutes.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 13
Incorrect
-
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: West Nile fever
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 14
Incorrect
-
A child under your supervision is diagnosed with a reportable illness.
Select from the options below the one condition that is currently a reportable illness.Your Answer: Erysipelas
Correct Answer: Scarlet fever
Explanation:The Health Protection (Notification) Regulations currently require the reporting of certain diseases. 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, SARS, scarlet fever, smallpox, tetanus, tuberculosis, typhus, viral haemorrhagic fever (VHF), whooping cough, and yellow fever.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 15
Correct
-
A child under your supervision is diagnosed with a reportable illness.
Which of the following is NOT currently a reportable illness?Your Answer: HIV
Explanation:HIV is currently not considered a notifiable disease. The Health Protection (Notification) Regulations require the reporting of certain diseases, but HIV is not included in this list. The diseases that are currently considered notifiable 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 diarrhea, invasive group A streptococcal disease, Legionnaires’ Disease, leprosy, malaria, measles, meningococcal septicaemia, mumps, plague, rabies, rubella, SARS, scarlet fever, smallpox, tetanus, tuberculosis, typhus, viral haemorrhagic fever (VHF), whooping cough, and yellow fever. If you want to learn more about notifiable diseases and the organisms that cause them, you can refer to the Notifiable diseases and causative organisms: how to report resource.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 16
Incorrect
-
A 42-year-old Emergency Medicine Resident presents after a night shift, having experienced a needle-stick injury while suturing a laceration with a flat-bladed suture needle.
Which SINGLE statement is true regarding their care?Your Answer: The risk of contracting hepatitis C from a hepatitis C positive source patient is between 0.3-1%
Correct Answer: More than 90% of people with hepatitis C can now be cured
Explanation:The risk of acquiring HIV from an HIV positive source patient ranges from 0.2% to 0.5%. On the other hand, the risk of contracting Hepatitis C from a Hepatitis C positive source patient is estimated to be between 3% and 10%.
When it comes to post-exposure prophylaxis for HIV, it is crucial to administer it within 72 hours after a needle-stick injury. The effectiveness of this prophylaxis decreases with time, so it should be given as soon as possible after the incident. For detailed guidelines on post-exposure prophylaxis, please refer to the DOH guidelines.
Unfortunately, there is currently no post-exposure prophylaxis available for Hepatitis C. However, there is a class of antiviral medications called nucleotide polymerase inhibitors that have revolutionized the treatment of Hepatitis C. These medications, such as sofosbuvir and daclatasvir, have shown remarkable efficacy in curing more than 90% of people with Hepatitis C. Moreover, they are easier to tolerate and have shorter treatment courses, making them a significant advancement in Hepatitis C treatment.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 17
Correct
-
You are asked to evaluate a 14 year old who has arrived at the emergency department with a sore throat, fatigue, and fever lasting for 5 days. After conducting your examination, you inform the patient that you suspect she may have mononucleosis.
Which of the following is a commonly known complication of mononucleosis?Your Answer: Splenic rupture
Explanation:Glandular fever, also known as infectious mononucleosis, can lead to a rare but potentially life-threatening complication called splenic rupture. Although splenomegaly (enlarged spleen) is common in glandular fever, it often does not cause any symptoms and cannot be felt during a physical examination. However, this increases the risk of splenic rupture, which can occur spontaneously or with minimal trauma. The spleen typically reaches its maximum size around two weeks into the illness before gradually shrinking. To prevent splenic rupture, patients are advised to avoid heavy lifting and contact sports for at least one month from the onset of the illness. Other complications of glandular fever include prolonged fatigue, mild hepatitis leading to jaundice, thrombocytopenia (low platelet count) with an increased risk of bleeding, neurological conditions such as Guillain-Barré syndrome, optic neuritis, Bell’s palsy, myocarditis, and nephritis.
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 18
Correct
-
A 32-year-old traveler returns from a visit to West Africa with frequent headaches and occasional fevers. Laboratory tests reveal the presence of malaria. The patient is promptly initiated on treatment, but his condition worsens, leading to the development of jaundice, renal failure, and haemoglobinuria.
What is the MOST LIKELY organism responsible for this illness?Your Answer: Plasmodium falciparum
Explanation:Malaria is a contagious illness that is spread by female mosquitoes of the Anopheles genus. It is a parasitic infection caused by the Plasmodium genus. There are five species of Plasmodium that are known to 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 pattern of symptoms. It begins with a cold phase, during which the patient experiences intense chills. This is followed by a hot stage, where the patient feels extremely hot. Finally, there is a sweating stage, during which the fever subsides and the patient sweats profusely. Upon examination, the patient may exhibit signs of anemia, jaundice, and have an enlarged liver and spleen, but there is no evidence of swollen lymph nodes.
If a patient develops haemoglobinuria (the presence of hemoglobin in the urine) and renal failure after treatment, it may indicate a condition called blackwater fever, which is caused by Plasmodium falciparum. In this condition, an autoimmune reaction occurs between the parasite and quinine, leading to the destruction of red blood cells, hemoglobinuria, jaundice, and renal failure. Blackwater fever can be life-threatening.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 19
Correct
-
A 57 year old type 2 diabetic presents to the emergency department with redness on his foot. Upon examination, a foot ulcer measuring 1 cm in diameter is observed, exposing the superficial subcutaneous tissues. There is approximately 1 cm of erythema surrounding the ulcer and some pus at the base. The patient is not running a fever and appears to be in good overall health. It is determined that antibiotics should be initiated. The patient has no known allergies to medications. Which antibiotic would be the most suitable option?
Your Answer: Flucloxacillin 500 mg four times a day for 7 days
Explanation:When treating diabetic foot ulcers that are infected, the severity of the ulcer is used to determine the appropriate antimicrobial therapy. In the case of a mild foot infection (PEDIS 2 grade), the first-line treatment is typically flucloxacillin. Based on the information provided, there is no indication that pseudomonas or MRSA should be suspected. For mild infections, it is reasonable to prescribe flucloxacillin at a dosage of 500 mg-1g four times a day for a duration of 7 days. It is important to reassess the patient at the end of the treatment course.
Further Reading:
Diabetic foot is a complication that can occur in individuals with diabetes due to long-standing high blood sugar levels. This leads to a process called glycation or glycosylation, where glucose binds to proteins and lipids in the body. Abnormal protein glycation can cause cellular dysfunction and various complications.
One of the main problems in diabetic foot is peripheral vascular disease and peripheral neuropathy. These conditions can result in significant foot issues, as trauma to the feet may go unnoticed and untreated. Vascular disease also impairs wound healing and increases the risk of developing ulcers.
Clinical features of diabetic foot include reduced sensation, especially to vibration, non-dermatomal sensory loss, foot deformities such as pes cavus and claw toes, and weak or absent foot pulses. It is important for diabetic patients to have their feet assessed regularly, at least annually, to identify any potential problems. Additional foot assessments should also be conducted during hospital admissions.
During a diabetic foot assessment, the healthcare provider should remove shoes, socks, and any bandages or dressings to examine both feet. They should assess for neuropathy using a 10 g monofilament to test foot sensation and check for limb ischemia by examining pulses and performing ankle brachial pressure index (ABPI) measurements. Any abnormal tissue, such as ulcers, calluses, infections, inflammation, deformities, or gangrene, should be documented. The risk of Charcot arthropathy should also be assessed.
The severity of foot ulcers in diabetic patients can be documented using standardized systems such as SINBAD or the University of Texas classification. The presence and severity of diabetic foot infection can be determined based on criteria such as local swelling, induration, erythema, tenderness, pain, warmth, and purulent discharge.
Management of foot ulcers involves offloading, control of foot infection, control of ischemia, wound debridement, and appropriate wound dressings. Antibiotics may be necessary depending on the severity of the infection. Diabetic patients with foot ulcers should undergo initial investigations including blood tests, wound swabs, and imaging to assess for possible osteomyelitis.
Charcot foot is a serious complication of diabetic peripheral neuropathy that results in progressive destructive arthropathy and foot deformity. Signs of Charcot foot include redness, swelling, warm skin, pain, and deformity. The hallmark deformity is midfoot collapse, known as the rocker-bottom foot.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 20
Correct
-
A 9-year-old boy comes to his pediatrician complaining of a headache, stiffness in his neck, and sensitivity to light. His vital signs are as follows: heart rate 124, blood pressure 86/43, respiratory rate 30, oxygen saturation 95%, and temperature 39.5°C. He has recently developed a rash of non-blanching petechiae on his legs.
What is the SINGLE most probable infectious agent responsible for these symptoms?Your Answer: Neisseria meningitidis group B
Explanation:In a child with a non-blanching rash, it is important to always consider the possibility of meningococcal septicaemia. This is especially true if the child appears unwell, has purpura (lesions larger than 2 mm in diameter), a capillary refill time of more than 3 seconds, or neck stiffness. In the UK, most cases of meningococcal septicaemia are caused by Neisseria meningitidis group B, although the vaccination program for Neisseria meningitidis group C has reduced the prevalence of this type. A vaccine for group B disease has now been introduced for children. It is also worth noting that Streptococcus pneumoniae can also cause meningitis.
In this particular case, the child is clearly very sick and showing signs of septic shock. It is crucial to administer a single dose of benzylpenicillin without delay and arrange for immediate transfer to the nearest Emergency Department via ambulance.
The recommended doses of benzylpenicillin based on age are as follows:
– Infants under 1 year of age: 300 mg of IM or IV benzylpenicillin
– Children aged 1 to 9 years: 600 mg of IM or IV benzylpenicillin
– Children and adults aged 10 years or older: 1.2 g of IM or IV benzylpenicillin. -
This question is part of the following fields:
- Infectious Diseases
-
-
Question 21
Correct
-
A 32 year old woman arrives at the emergency department complaining of abdominal pain, fever, and yellowing of her skin and eyes. Upon examination, it is evident that she is clinically jaundiced. The patient has a history of intravenous drug use. You suspect she may have acute hepatitis B infection. Which of the following serology results would best support this diagnosis?
Your Answer: HBsAg positive and anti-HBc IgM positive
Explanation:The presence of serum HBsAg for more than 6 months indicates chronic HBV infection. HBeAg can be detected in the serum during the early stages of acute infection and some chronic infections. Higher levels of virus replication are usually associated with the presence of HBeAg, making individuals with chronic HBV more infectious. If HBeAg is cleared, anti-HBe is typically detected, indicating lower infectivity. The presence of anti-HBe, along with a decline in HBV-DNA, suggests control of viral replication and the likelihood of resolving acute hepatitis B. The presence of anti-HBc indicates current or past HBV infection, appearing at the onset of symptoms in acute infection and persisting for life. However, it may be absent in the early stages of acute infection. Anti-HBc IgM indicates recent HBV infection within the last six months and can help differentiate between acute and chronic infection. Over time, it is gradually replaced by IgG anti-HBc. IgG anti-HBc generally persists for life and indicates past infection. Anti-HBs indicates recovery from and immunity to HBV. If anti-HBs is present without anti-HBc, it suggests immunization. The quantification of anti-HBs is used to measure the response to vaccination.
Further Reading:
Hepatitis B is a viral infection that is transmitted through exposure to infected blood or body fluids. It can also be passed from mother to child during childbirth. The incubation period for hepatitis B is typically 6-20 weeks. Common symptoms of hepatitis B include fever, jaundice, and elevated liver transaminases.
Complications of hepatitis B infection can include chronic hepatitis, which occurs in 5-10% of cases, fulminant liver failure, hepatocellular carcinoma, glomerulonephritis, polyarteritis nodosa, and cryoglobulinemia.
Immunization against hepatitis B is recommended for various at-risk groups, including healthcare workers, intravenous drug users, sex workers, close family contacts of infected individuals, and those with chronic liver disease or kidney disease. The vaccine contains HBsAg adsorbed onto an aluminum hydroxide adjuvant and is prepared using recombinant DNA technology. Most vaccination schedules involve three doses of the vaccine, with a booster recommended after 5 years.
Around 10-15% of adults may not respond adequately to the vaccine. Risk factors for poor response include age over 40, obesity, smoking, alcohol excess, and immunosuppression. Testing for anti-HBs levels is recommended for healthcare workers and patients with chronic kidney disease. Interpretation of anti-HBs levels can help determine the need for further vaccination or testing for infection.
In terms of serology, the presence of HBsAg indicates acute disease if present for 1-6 months, and chronic disease if present for more than 6 months. Anti-HBs indicates immunity, either through exposure or immunization. Anti-HBc indicates previous or current infection, with IgM anti-HBc appearing during acute or recent infection and IgG anti-HBc persisting. HbeAg is a marker of infectivity.
Management of hepatitis B involves notifying the Health Protection Unit for surveillance and contact tracing. Patients should be advised to avoid alcohol and take precautions to minimize transmission to partners and contacts. Referral to a gastroenterologist or hepatologist is recommended for all patients. Symptoms such as pain, nausea, and itch can be managed with appropriate drug treatment. Pegylated interferon-alpha and other antiviral medications like tenofovir and entecavir may be used to suppress viral replication in chronic carriers.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 22
Correct
-
A child with a history of stomach pain and loose stools is being examined for a potential diagnosis of tapeworm infection.
What is the most suitable test to confirm this diagnosis?Your Answer: Recover eggs from stool sample
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 23
Correct
-
A 30-year-old man presents to the emergency department following an altercation at a nightclub. The patient sustained a bite during the altercation, resulting in an occlusal injury to his arm. There is notable redness surrounding the wound. It is determined that the patient should be administered antibiotics. What is the most suitable initial antibiotic treatment for an infected human bite wound?
Your Answer: Co-amoxiclav
Explanation:When it comes to preventing infection in human bite wounds, Co-amoxiclav is the recommended first-line antibiotic prophylaxis. Human bites can occur either from biting or from clenched-fist injuries, commonly known as fight bites. Co-amoxiclav is the preferred choice for prophylaxis in cases where there is a risk of infection or when an infection is already present in a human bite wound.
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 24
Correct
-
A 15 year old arrives at the emergency department complaining of a sore throat, swollen glands, and feeling tired for the past 9 days. Glandular fever is suspected. What test should be ordered to confirm the diagnosis?
Your Answer: Monospot test
Explanation:The monospot test is the preferred method for testing for infectious mononucleosis (glandular fever) when looking for heterophile antibodies. The timing and choice of investigations for glandular fever depend on factors such as the patient’s age, immune system status, and duration of symptoms. The monospot test is a latex agglutination test that uses equine erythrocytes as the primary substrate to detect specific heterophile antibodies produced by the human immune system in response to EBV infection. It is simpler and faster to use compared to the Paul Bunnell test, which uses sheep red cells. The monospot test is recommended by NICE due to its advantages. However, it has lower sensitivity and negative predictive value in young children, which is why EBV serology is preferred for those under 12 years old.
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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 25
Incorrect
-
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: Plasmodium vivax is usually treated with quinine
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,
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 26
Correct
-
A 35-year-old traveler returns from a vacation in India with a high temperature and stomach issues. After medical examination, he is confirmed to have typhoid fever.
Your Answer: The incubation period is between 7 and 21 days
Explanation:Typhoid fever is a bacterial infection caused by Salmonella typhi. Paratyphoid fever, on the other hand, is a similar illness caused by Salmonella paratyphi. Together, these two conditions are collectively known as the enteric fevers.
Typhoid fever is prevalent in India and many other parts of Asia, Africa, Central America, and South America. It is primarily transmitted through the consumption of contaminated food or water that has been infected by the feces of an acutely infected or recovering person, or a chronic carrier. About 1-6% of individuals infected with S. typhi become chronic carriers. The incubation period for this illness ranges from 7 to 21 days.
During the first week of the illness, patients experience weakness and lethargy, accompanied by a gradually increasing fever. The onset of the illness is usually subtle, and constipation is more common than diarrhea in the early stages. Other early symptoms include headaches, abdominal pain, and nosebleeds. In cases of typhoid fever, the fever can occur with a relatively slow heart rate, known as Faget’s sign.
As the illness progresses into the second week, patients often become too fatigued to get out of bed. Diarrhea becomes more prominent, the fever intensifies, and patients may become agitated and delirious. The abdomen may become tender and swollen, and approximately 75% of patients develop an enlarged spleen. In up to a third of patients, red macules known as Rose spots may appear.
In the third week, the illness can lead to various complications. Intestinal bleeding may occur due to bleeding in congested Peyer’s patches. Other potential complications include intestinal perforation, secondary pneumonia, encephalitis, myocarditis, metastatic abscesses, and septic shock.
After the third week, surviving patients begin to show signs of improvement, with the fever and symptoms gradually subsiding over the course of 7-14 days. Untreated patients have a mortality rate of 15-30%. Traditionally, drugs like ampicillin and trimethoprim have been used for treatment. However, due to the emergence of multidrug resistant cases, azithromycin or fluoroquinolones are now the primary treatment options.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 27
Incorrect
-
A 22-year-old traveler returns from a recent backpacking trip to Africa with headaches and intermittent fevers. He describes intense chills, followed by feeling hot and then sweating profusely.
On examination, he is drowsy and has a temperature of 39.4°C. You perform a bedside blood glucose measurement, which is 1.9 mmol/l. There are no palpable lymph nodes or rash, but examination of his abdomen reveals hepatosplenomegaly. Intravenous glucose is administered, and his blood glucose improves to 4.4 mmol/l.
His blood tests today are as follows:
Hemoglobin: 7.8 g/dl (13-17 g/dl)
Platelets: 46 x 109/l (150-400 x 109/l)
White blood cell count: 10.7 x 109/l (4-11 x 109/l)
Sodium: 134 mmol/L (135-147 mmol/L)
Potassium: 4.9 mmol/L (3.5-5.5 mmol/L)
Urea: 11.5 mmol/L (2.0-6.6 mmol/L)
Creatinine: 278 mmol/L (75-125 mmol/L)
What is the SINGLE most appropriate first-line treatment?Your Answer: Primaquine
Correct Answer: Artemisinin-based combination therapy
Explanation:Malaria is an infectious disease caused by the female Anopheles mosquito. It is caused by the Plasmodium parasite and there are five species that can infect humans. These species are Plasmodium falciparum, Plasmodium ovale, Plasmodium vivax, Plasmodium malariae, and Plasmodium knowlesi.
The main symptom of malaria is the malarial paroxysm, which is a cyclical occurrence of cold chills, followed by intense heat, and then profuse sweating. Upon examination, patients with malaria may show signs of anemia, jaundice, and have an enlarged liver and spleen. The full blood count often reveals a combination of anemia and low platelet count.
Plasmodium falciparum is the most severe form of malaria and is responsible for most deaths. Severe malaria is indicated by symptoms such as impaired consciousness, seizures, low blood sugar, anemia, kidney problems, difficulty breathing, and spontaneous bleeding. Given the presentation, it is likely that this patient has Plasmodium falciparum malaria.
Thick and thin blood films are the gold-standard diagnostic tests for malaria. However, it is possible for a patient to have malaria even if the blood film is negative. In such cases, at least two additional blood films should be obtained within 48 hours to confirm or exclude the diagnosis.
Artemisinin-based combination therapy (ACT) is currently recommended for the treatment of Plasmodium falciparum malaria. ACT involves combining fast-acting artemisinin-based drugs with another drug from a different class. Some companion drugs used in ACT include lumefantrine, mefloquine, amodiaquine, sulfadoxine/pyrimethamine, piperaquine, and chlorproguanil/dapsone. If ACT is not available, oral quinine or atovaquone with proguanil hydrochloride can be used. Quinine should be combined with another drug, usually oral doxycycline, for prolonged treatment.
Severe or complicated cases of Plasmodium 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 malaria, or those at high risk of developing severe disease. After a minimum of 24 hours of intravenous treatment, and when the patient
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 28
Correct
-
A 2-year-old toddler is brought to the Emergency Department by his father with a high temperature. NICE suggests using the traffic light system to evaluate the likelihood of a severe illness in children under 3 with a fever.
Based on the NICE traffic light system, which of the subsequent symptoms or signs are indicative of an intermediate-risk of a severe illness?Your Answer: Dry mucous membranes
Explanation:The traffic light system is a useful tool for evaluating the potential risk of serious illness in children. This system categorizes clinical features into three groups based on severity: red (high-risk), amber (intermediate-risk), and green (low-risk).
Children displaying any of the following symptoms or signs fall into the high-risk group for serious illness: pale/mottled/ashen/blue skin, lips or tongue; lack of response to social cues; appearing unwell to a healthcare professional; inability to wake or stay awake when roused; weak, high-pitched, or continuous cry; grunting; respiratory rate exceeding 60 breaths per minute; moderate or severe chest indrawing; reduced skin turgor; and bulging fontanelle.
Children exhibiting any of the following symptoms or signs are considered at least intermediate-risk for serious illness: pallor of skin, lips or tongue reported by parent or caregiver; abnormal response to social cues; absence of a smile; waking only with prolonged stimulation; decreased activity; nasal flaring; dry mucous membranes; poor feeding in infants; reduced urine output; and rigors.
Children displaying any of the following symptoms or signs are classified as low-risk for serious illness: normal color of skin, lips, and tongue; normal response to social cues; contentment and smiles; staying awake or quickly awakening; strong normal cry or absence of crying; normal skin and eyes; and moist mucous membranes.
To summarize, children with fever and any symptoms or signs in the red column are considered high-risk, while those with fever and any symptoms or signs in the amber column (but none in the red column) are considered intermediate-risk. Children with symptoms and signs in the green column (and none in the amber or red columns) are classified as low-risk.
For more information, you can refer to the NICE guidelines on the assessment and initial management of fever in children under 5, as well as the NICE Clinical Knowledge Summary on the management of feverish children.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 29
Correct
-
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: 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.
-
This question is part of the following fields:
- Infectious Diseases
-
-
Question 30
Correct
-
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: 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.
-
This question is part of the following fields:
- Infectious Diseases
-
00
Correct
00
Incorrect
00
:
00
:
0
00
Session Time
00
:
00
Average Question Time (
Mins)