For the treatment of young people under 16 years with lower urinary tract infection (UTI), it is important to obtain a urine sample before starting antibiotics. This sample can be tested using a dipstick or sent for culture and susceptibility testing. In cases where children under 5 present with fever along with lower UTI, it is recommended to follow the guidance outlined in the NICE guideline on fever in under 5s.

Immediate antibiotic prescription should be offered to children and young people under 16 years with lower UTI. When making this prescription, it is important to consider previous urine culture and susceptibility results, as well as any history of antibiotic use that may have led to resistant bacteria. If a urine sample has been sent for culture and sensitivity testing, the choice of antibiotic should be reviewed once the microbiological results are available. If the bacteria are found to be resistant and symptoms are not improving, a narrow-spectrum antibiotic should be used whenever possible.

For non-pregnant women aged 16 years and under, the following antibiotics can be considered:
– Children under 3 months: It is recommended to refer to a pediatric specialist and treat with an intravenous antibiotic in line with the NICE guideline on fever in under 5s.
– First-choice in children over 3 months: Nitrofurantoin (if eGFR >45 ml/minute) or Trimethoprim (if low risk of resistance*).
– Second-choice in children over 3 months (when there is no improvement in lower UTI symptoms on first-choice for at least 48 hours, or when first-choice is not suitable): Nitrofurantoin (if eGFR >45 ml/minute and not used as first-choice), Amoxicillin (only if culture results are available and susceptible), or Cefalexin.

Please refer to the BNF for children for dosing information. It is important to consider the risk of resistance when choosing antibiotics. A lower risk of resistance may be more likely if the antibiotic has not been used in the past 3 months, if previous urine culture suggests susceptibility (but was not used), and in younger people in areas where local epidemiology data suggest low resistance. On the other hand, a higher risk of resistance may be more likely with recent antibiotic use and in older people in residential facilities.

To treat low sodium levels, a solution of sodium chloride is administered. It is important to regularly monitor plasma sodium levels every 2 hours during this treatment, but it is crucial to avoid taking samples from the arm where the IV is inserted. The increase in serum sodium should not exceed 2 mmol/L per hour and should not exceed 8 to 10 mmol/L within a 24-hour period. Hypertonic saline is administered intravenously until neurological symptoms improve.

Further Reading:

Syndrome of inappropriate antidiuretic hormone (SIADH) is a condition characterized by low sodium levels in the blood due to excessive secretion of antidiuretic hormone (ADH). ADH, also known as arginine vasopressin (AVP), is responsible for promoting water and sodium reabsorption in the body. SIADH occurs when there is impaired free water excretion, leading to euvolemic (normal fluid volume) hypotonic hyponatremia.

There are various causes of SIADH, including malignancies such as small cell lung cancer, stomach cancer, and prostate cancer, as well as neurological conditions like stroke, subarachnoid hemorrhage, and meningitis. Infections such as tuberculosis and pneumonia, as well as certain medications like thiazide diuretics and selective serotonin reuptake inhibitors (SSRIs), can also contribute to SIADH.

The diagnostic features of SIADH include low plasma osmolality, inappropriately elevated urine osmolality, urinary sodium levels above 30 mmol/L, and euvolemic. Symptoms of hyponatremia, which is a common consequence of SIADH, include nausea, vomiting, headache, confusion, lethargy, muscle weakness, seizures, and coma.

Management of SIADH involves correcting hyponatremia slowly to avoid complications such as central pontine myelinolysis. The underlying cause of SIADH should be treated if possible, such as discontinuing causative medications. Fluid restriction is typically recommended, with a daily limit of around 1000 ml for adults. In severe cases with neurological symptoms, intravenous hypertonic saline may be used. Medications like demeclocycline, which blocks ADH receptors, or ADH receptor antagonists like tolvaptan may also be considered.

It is important to monitor serum sodium levels closely during treatment, especially if using hypertonic saline, to prevent rapid correction that can lead to central pontine myelinolysis. Osmolality abnormalities can help determine the underlying cause of hyponatremia, with increased urine osmolality indicating dehydration or renal disease, and decreased urine osmolality suggesting SIADH or overhydration.

To clinically test for Le Fort fractures, one can perform the following procedure: Place one hand on the forehead to stabilize it, and with the other hand, gently grip the upper teeth and anterior maxilla. Then, gently rock the hard palate back and forth.

This test is useful in suspected cases of Le Fort fractures. In a Le Fort I fracture, only the teeth and hard palate will move, while the rest of the mid face and skull remain still. In Le Fort II fractures, the teeth, hard palate, and nose will move, but the eyes and zygomatic arches will remain still. In Le Fort III fractures, the entire face will move in relation to the forehead.

Further Reading:

The Le Fort fracture classification describes three fracture patterns seen in midface fractures, all involving the maxilla and pterygoid plate disruption. As the classification grading increases, the anatomic level of the maxillary fracture ascends from inferior to superior.

Le Fort I fractures, also known as floating palate fractures, typically result from a downward blow struck above the upper dental row. Signs include swelling of the upper lip, bruising to the upper buccal sulcus, malocclusion, and mobile upper teeth.

Le Fort II fractures, also known as floating maxilla fractures, are typically the result of a forceful blow to the midaxillary area. Signs include a step deformity at the infraorbital margin, oedema over the middle third of the face, sensory disturbance of the cheek, and bilateral circumorbital ecchymosis.

Le Fort III fractures, also known as craniofacial dislocation or floating face fractures, are typically the result of high force blows to the nasal bridge or upper maxilla. These fractures involve the zygomatic arch and extend through various structures in the face. Signs include tenderness at the frontozygomatic suture, lengthening of the face, enophthalmos, and bilateral circumorbital ecchymosis.

Management of Le Fort fractures involves securing the airway as a priority, following the ABCDE approach, and identifying and managing other injuries, especially cervical spine injuries. Severe bleeding may occur and should be addressed appropriately. Surgery is almost always required, and patients should be referred to maxillofacial surgeons. Other specialties, such as neurosurgery and ophthalmology, may need to be involved depending on the specific case.

Respiratory alkalosis can be caused by hyperventilation, such as during periods of anxiety. It can also be a result of conditions like pulmonary embolism, CNS disorders (such as stroke or encephalitis), altitude, pregnancy, or the early stages of aspirin overdose.

Respiratory acidosis is often associated with chronic obstructive pulmonary disease (COPD) or life-threatening asthma. Other causes include pulmonary edema, sedative drug overdose (such as opiates or benzodiazepines), neuromuscular disease, obesity, or certain medications.

Metabolic alkalosis can occur due to vomiting, potassium depletion (often caused by diuretic usage), Cushing’s syndrome, or Conn’s syndrome.

Metabolic acidosis with a raised anion gap can be caused by conditions like lactic acidosis (which can result from hypoxemia, shock, sepsis, or infarction) or ketoacidosis (commonly seen in diabetes, starvation, or alcohol excess). Other causes include renal failure or poisoning (such as late stages of aspirin overdose, methanol, or ethylene glycol).

Metabolic acidosis with a normal anion gap can be attributed to conditions like renal tubular acidosis, diarrhea, ammonium chloride ingestion, or adrenal insufficiency.

Extrapyramidal side effects are most commonly seen with the piperazine phenothiazines (fluphenazine, prochlorperazine, and trifluoperazine) and butyrophenones (benperidol and haloperidol). Among these, haloperidol is the most frequently implicated antipsychotic drug.

Tardive dyskinesia, which involves involuntary rhythmic movements of the tongue, face, and jaw, typically occurs after prolonged treatment or high doses. It is the most severe manifestation of extrapyramidal symptoms, as it may become irreversible even after discontinuing the causative medication, and treatment options are generally ineffective.

Dystonia, characterized by abnormal movements of the face and body, is more commonly observed in children and young adults and tends to appear after only a few doses. Acute dystonia can be managed with intravenous administration of procyclidine (5 mg) or benzatropine (2 mg) as a bolus.

Akathisia refers to an unpleasant sensation of restlessness, while akinesia refers to an inability to initiate movement.

In individuals with renal impairment, there is an increased sensitivity of the brain to antipsychotic drugs, necessitating the use of reduced doses.

Elderly patients with dementia-related psychosis who are treated with haloperidol face an elevated risk of mortality. This is believed to be due to an increased likelihood of cardiovascular events and infections such as pneumonia.

Contraindications for the use of antipsychotic drugs include reduced consciousness or coma, central nervous system depression, and the presence of phaeochromocytoma.

The interpretation of facial X-rays is often assisted by the use of McGrigor-Campbell lines and Dolan lines. These lines, along with accompanying notes and images, provide additional information for a more accurate analysis.

Further Reading:

Facial X-rays are commonly used to assess and diagnose facial fractures. Two standard views are typically performed: the Occipitomental view and the Occipitomental 30º view. The Occipitomental view provides a comprehensive look at the upper and middle thirds of the face, including the orbital margins, frontal sinuses, zygomatic arches, and maxillary antra. On the other hand, the Occipitomental 30º view uses a 30-degree caudal angulation to better visualize the zygomatic arches and walls of the maxillary antra, although it may compromise the clear view of the orbital margins.

To assist in the interpretation of facial X-rays, imaginary lines are often drawn across the images to highlight any asymmetry or disruption. Two commonly used sets of lines are the McGrigor-Campbell lines and Dolan’s lines. McGrigor-Campbell lines are used to aid in the interpretation of both the Occipitomental and Occipitomental 30º views. These lines include an upper line that passes through the zygomatico-frontal sutures and the upper edge of the orbits, a middle line that follows the zygomatic arch and crosses the zygomatic bone, and a lower line that passes through the condyle and coronoid process of the mandible and the walls of the maxillary antra.

Dolan’s lines, described by Dolan and Jacoby, are often used in conjunction with McGrigor-Campbell lines. These lines include the orbital line, which traces the inner margins of the orbital walls and the nasal arch, the zygomatic line, which traces the superior margin of the zygomatic arch and body, and the maxillary line, which traces the inferior margin of the zygomatic arch, body, and buttress, as well as the lateral wall of the maxillary sinus. Together, the zygomatic and maxillary lines resemble the profile of an elephant’s head and are referred to as Dolan’s elephant. These lines help provide additional information and aid in the interpretation of facial X-rays.

Ondansetron is a medication that works by blocking serotonin receptors in the body. It is commonly used as a first-line treatment for postoperative nausea and vomiting (PONV), which can occur after procedures done under sedation or anesthesia.

Further Reading:

postoperative nausea and vomiting (PONV) is a common occurrence following procedures performed under sedation or anesthesia. It can be highly distressing for patients. Several risk factors have been identified for PONV, including female gender, a history of PONV or motion sickness, non-smoking status, patient age, use of volatile anesthetics, longer duration of anesthesia, perioperative opioid use, use of nitrous oxide, and certain types of surgery such as abdominal and gynecological procedures.

To manage PONV, antiemetics are commonly used. These medications work by targeting different receptors in the body. Cyclizine and promethazine are histamine H1-receptor antagonists, which block the action of histamine and help reduce nausea and vomiting. Ondansetron is a serotonin 5-HT3 receptor antagonist, which blocks the action of serotonin and is effective in preventing and treating PONV. Prochlorperazine is a dopamine D2 receptor antagonist, which blocks the action of dopamine and helps alleviate symptoms of nausea and vomiting. Metoclopramide is also a dopamine D2 receptor antagonist and a 5-HT3 receptor antagonist, providing dual action against PONV. It is also a 5-HT4 receptor agonist, which helps improve gastric emptying and reduces the risk of PONV.

Assessment and management of PONV involves a comprehensive approach. Healthcare professionals need to assess the patient’s risk factors for PONV and take appropriate measures to prevent its occurrence. This may include selecting the appropriate anesthesia technique, using antiemetics prophylactically, and providing adequate pain control. In cases where PONV does occur, prompt treatment with antiemetics should be initiated to alleviate symptoms and provide relief to the patient. Close monitoring of the patient’s condition and response to treatment is essential to ensure effective management of PONV.

Renal colic, also known as ureteric colic, refers to a sudden and intense pain in the lower back caused by a blockage in the ureter, which is the tube that carries urine from the kidney to the bladder. This condition is commonly associated with the presence of a urinary tract stone.

The main symptoms of renal or ureteric colic include severe abdominal pain on one side, starting in the lower back or flank and radiating to the groin or genital area in men, or to the labia in women. The pain comes and goes in spasms, lasting for minutes to hours, with periods of no pain or a dull ache. Nausea, vomiting, and the presence of blood in the urine are often accompanying symptoms.

People experiencing renal or ureteric colic are usually restless and unable to find relief by lying still, which helps to distinguish this condition from peritonitis. They may have a history of previous episodes and may also present with fever and sweating if there is an associated urinary infection. Some individuals may complain of painful urination, frequent urination, and straining when the stone reaches the junction between the ureter and the bladder, as the stone irritates the detrusor muscle.

In terms of pain management, the first-line treatment for adults, children, and young people with suspected renal colic is a non-steroidal anti-inflammatory drug (NSAID), which can be administered through various routes. If NSAIDs are contraindicated or not providing sufficient pain relief, intravenous paracetamol can be offered as an alternative. Opioids may be considered if both NSAIDs and intravenous paracetamol are contraindicated or not effective in relieving pain. Antispasmodics should not be given to individuals with suspected renal colic.

For more detailed information, you can refer to the NICE guidelines on the assessment and management of renal and ureteric stones.

Subfalcine herniation occurs when a mass in one side of the brain causes the cingulate gyrus to be pushed under the falx cerebri. This condition often leads to specific neurological symptoms. These symptoms include a motor deficit in the lower limb on the opposite side of the body, bladder incontinence, motor and sensory deficits on the same side of the body as the herniation, and difficulty with speech (dysarthria).

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

Central retinal vein occlusion (CRVO) typically results in painless, one-sided vision loss. On fundoscopic examination, the retina displays a distinct appearance resembling a ‘pizza thrown against a wall’. This includes engorged retinal veins, swelling of the optic disc, multiple flame-shaped hemorrhages, and cotton wool spots. Hypertension is present in about 65% of CRVO patients, and it is more common in individuals over 65 years old.

In contrast, central retinal artery occlusion (CRAO) also causes sudden, painless, one-sided vision loss. However, the retina’s appearance in CRAO is different from CRVO. It appears pale, with narrowed blood vessels. A notable feature is the presence of a ‘cherry-red spot’ at the center of the macula, which is supplied by the underlying choroid. Examination often reveals an afferent pupillary defect.

Vitreous hemorrhage occurs when there is bleeding into the middle chamber of the eye, known as the vitreous. This can be caused by conditions such as proliferative diabetic retinopathy, trauma, or retinal detachment. The appearance of vitreous hemorrhage is described as ‘blood within a bloodless gel’, resulting in a diffuse red appearance of the retina. Unlike CRVO, there are no focal flame-shaped hemorrhages.

Diabetic maculopathy refers to the presence of diabetic eye disease within a one-disc diameter of the macula.

Wet age-related macular degeneration (ARMD) causes vision loss due to choroidal neovascularization, which leads to leakage of blood and protein beneath the macula. While there may be hemorrhages visible on the retina, the overall appearance does not match the description provided in the question.

Discitis is an infection that affects the space between the intervertebral discs in the spine. This condition can have serious consequences, including the formation of abscesses and sepsis. The most common cause of discitis is usually Staphylococcus aureus, but other organisms like Streptococcus viridans and Pseudomonas aeruginosa may be responsible in certain cases, especially in immunocompromised individuals and intravenous drug users. Gram-negative organisms like Escherichia coli and Mycobacterium tuberculosis can also cause discitis, particularly in cases of Pott’s disease.

There are several risk factors that increase the likelihood of developing discitis. These include having undergone spinal surgery (which occurs in about 1-2% of patients post-operatively), having an immunodeficiency, being an intravenous drug user, being under the age of eight, having diabetes mellitus, or having a malignancy.

The typical symptoms of discitis include back or neck pain (which occurs in over 90% of cases), pain that often wakes the patient from sleep, fever (present in 60-70% of cases), and neurological deficits (which can occur in up to 50% of cases). In children, a refusal to walk may also be a symptom.

When diagnosing discitis, magnetic resonance imaging (MRI) is the preferred imaging modality due to its high sensitivity and specificity. It is important to image the entire spine, as discitis often affects multiple levels. Plain radiographs are not very sensitive to the early changes of discitis and may appear normal for 2-4 weeks. Computed tomography (CT) scanning is also not very sensitive in detecting discitis.

Treatment for discitis involves hospital admission for intravenous antibiotics. Before starting the antibiotics, it is recommended to send three sets of blood cultures and a full set of blood tests, including a C-reactive protein (CRP) test, to the laboratory.

A typical antibiotic regimen for discitis would include intravenous flucloxacillin 2 g every 6 hours as the first-line treatment if there is no penicillin allergy. Intravenous vancomycin may be used if the infection was acquired in the hospital, if there is a high risk of methicillin-resistant Staphylococcus aureus (MRSA) infection, or if there is a documented penicillin allergy.

In the blood tests, certain findings can support a diagnosis of glandular fever. One of these findings is lymphocytosis, which refers to an increased number of lymphocytes in the blood. Lymphocytes are a type of white blood cell that plays a crucial role in the immune response. In glandular fever, the Epstein-Barr virus (EBV) is the most common cause, and it primarily infects and activates lymphocytes, leading to their increased numbers in the blood.

On the other hand, neutropenia (a decreased number of neutrophils) and neutrophilia (an increased number of neutrophils) are not typically associated with glandular fever. Neutrophils are another type of white blood cell that helps fight off bacterial infections. In glandular fever, the primary involvement is with lymphocytes rather than neutrophils.

Monocytosis, which refers to an increased number of monocytes, can also be seen in glandular fever. Monocytes are another type of white blood cell that plays a role in the immune response. Their increased numbers can be a result of the immune system’s response to the Epstein-Barr virus.

Eosinophilia, an increased number of eosinophils, is not commonly associated with glandular fever. Eosinophils are white blood cells involved in allergic reactions and parasitic infections, and their elevation is more commonly seen in those conditions.

In summary, the presence of lymphocytosis and possibly monocytosis in the blood tests would support a diagnosis of glandular fever, while neutropenia, neutrophilia, and eosinophilia are less likely to be associated with this condition.

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.

In patients of this age who have experienced a change in bowel habit, rectal bleeding, and weight loss, the most probable diagnosis is colorectal carcinoma. Considering the patient’s history and examination findings, the other options in this question are significantly less likely. It is crucial to refer this patient promptly to a specialized team that focuses on the treatment of lower gastrointestinal cancer.

Ipratropium bromide commonly leads to dry mouth as a side effect. Additionally, it may result in constipation, cough, sudden bronchospasm, headache, nausea, and palpitations. In patients with prostatic hyperplasia and bladder outflow obstruction, it can cause urinary retention. Furthermore, susceptible individuals may experience acute closed-angle glaucoma as a result of using this medication.

Erb’s palsy, also known as Erb-Duchenne palsy, is a condition where the arm becomes paralyzed due to an injury to the upper roots of the brachial plexus. The primary root affected is usually C5, although C6 may also be involved in some cases. The main cause of Erb’s palsy is when the arm experiences excessive force during a difficult childbirth, but it can also occur in adults as a result of shoulder trauma.

Clinically, the affected arm will hang by the side with the elbow extended and the forearm turned inward (known as the waiter’s tip sign). Upon examination, there will be a loss of certain movements:

– Shoulder abduction (involving the deltoid and supraspinatus muscles)
– Shoulder external rotation (infraspinatus muscle)
– Elbow flexion (biceps and brachialis muscles)

It is important to differentiate Erb’s palsy from Klumpke’s palsy, which affects the lower roots of the brachial plexus (C8 and T1). Klumpke’s palsy presents with a claw hand due to paralysis of the intrinsic hand muscles, along with sensory loss along the ulnar side of the forearm and hand. If T1 is affected, there may also be the presence of Horner’s syndrome.

In an elderly patient with a history of gradual decline accompanied by high blood sugar levels, excessive thirst, and recent infection, the most likely diagnosis is hyperosmolar hyperglycemic state (HHS). This condition can be life-threatening, with a mortality rate of approximately 50%. Common symptoms include dehydration, elevated blood sugar levels, altered mental status, and electrolyte imbalances. About half of the patients with HHS also experience hypernatremia.

To calculate the serum osmolality, the formula is 2(K+ + Na+) + urea + glucose. In this case, the serum osmolality is 364 mmol/l, indicating a high level. It is important to discontinue the use of metformin in this patient due to the risk of metformin-associated lactic acidosis (MALA). Additionally, an intravenous infusion of insulin should be initiated.

The treatment goals for HHS are to address the underlying cause and gradually and safely:
– Normalize the osmolality
– Replace fluid and electrolyte losses
– Normalize blood glucose levels

If significant ketonaemia is present (3β-hydroxybutyrate is more than 1 mmol/L), it indicates a relative lack of insulin, and insulin should be administered immediately. However, if significant ketonaemia is not present, insulin should not be started.

Patients with HHS are at a high risk of thromboembolism, and it is recommended to routinely administer low molecular weight heparin. In cases where the serum osmolality exceeds 350 mmol/l, full heparinization should be considered.

The BTS guidelines for managing acute asthma in children over the age of 2 recommend the following approaches:

Bronchodilator therapy is the first-line treatment for acute asthma. Inhaled β agonists are preferred, and a pmDI + spacer is the recommended option for children with mild to moderate asthma. It is important to individualize drug dosing based on the severity of the condition and adjust it according to the patient’s response. If initial β agonist treatment does not alleviate symptoms, ipratropium bromide can be added to the nebulized β2 agonist solution. In cases where children with a short duration of acute severe asthma symptoms have an oxygen saturation level below 92%, it is advisable to consider adding 150 mg of magnesium sulfate to each nebulized salbutamol and ipratropium within the first hour.

Long-acting β2 agonists should be discontinued if short-acting β2 agonists are required more frequently than every four hours.

Steroid therapy should be initiated early in the treatment of acute asthma attacks. For children aged 2-5 years, a dose of 20 mg prednisolone is recommended, while children over the age of 5 should receive a dose of 30-40 mg. Children already on maintenance steroid tablets should receive 2 mg/kg prednisolone, up to a maximum dose of 60 mg. If a child vomits after taking the initial dose of prednisolone, the dose should be repeated. In cases where a child is unable to retain orally ingested medication, intravenous steroids should be considered. Typically, treatment with oral steroids for up to three days is sufficient, but the duration of the course should be adjusted based on the time needed for recovery. Tapering is not necessary unless the course of steroids exceeds 14 days.

In cases where initial inhaled therapy does not yield a response in severe asthma attacks, the early addition of a single bolus dose of intravenous salbutamol (15 micrograms/kg over 10 minutes) should be considered. Aminophylline is not recommended for children with mild to moderate acute asthma, but it may be considered for those with severe or life-threatening asthma that is unresponsive to maximum doses of bronchodilators and steroids. The use of IV magnesium sulfate as a treatment for acute asthma in children is considered safe, although its role in management is not yet fully established.

Pityriasis versicolor, also known as tinea versicolor, is a common skin condition caused by an infection with the yeasts Malassezia furfur and Malassezia globosa. It typically presents as multiple patches of altered pigmentation, primarily on the trunk. In individuals with fair skin, these patches are usually darker in color, while in those with darker skin or a tan, they may appear lighter (known as pityriasis versicolor alba). It is not uncommon for the rash to cause itching.

The recommended treatment for pityriasis versicolor involves the use of antifungal agents. One particularly effective option is ketoconazole shampoo, which is sold under the brand name Nizoral. To use this shampoo, it should be applied to the affected areas and left on for approximately five minutes before being rinsed off. This process should be repeated daily for a total of five days.

Pericarditis refers to the inflammation of the pericardium, which can be caused by various factors such as infections (typically viral, like coxsackie virus), drug-induced reactions (e.g. isoniazid, cyclosporine), trauma, autoimmune conditions (e.g. SLE), paraneoplastic syndromes, uraemia, post myocardial infarction (known as Dressler’s syndrome), post radiotherapy, and post cardiac surgery.

The clinical presentation of pericarditis often includes retrosternal chest pain that is pleuritic in nature. This pain is typically relieved by sitting forwards and worsened when lying flat. It may also radiate to the shoulders. Other symptoms may include shortness of breath, tachycardia, and the presence of a pericardial friction rub.

The pericardium receives sensory supply from the phrenic nerve, which also provides sensory innervation to the diaphragm, various mediastinal structures, and certain abdominal structures such as the superior peritoneum, liver, and gallbladder. Since the phrenic nerve originates from the 4th cervical nerve, which also provides cutaneous innervation to the front of the shoulder girdle, pain from pericarditis can also radiate to the shoulders.

The classic ECG features of atrial fibrillation include an irregularly irregular rhythm, the absence of p-waves, an irregular ventricular rate, and the presence of fibrillation waves. This irregular rhythm occurs because the atrial impulses are filtered out by the AV node.

In addition, Ashman beats may be observed in atrial fibrillation. These beats are characterized by wide complex QRS complexes, often with a morphology resembling right bundle branch block. They occur after a short R-R interval that is preceded by a prolonged R-R interval. Fortunately, Ashman beats are generally considered harmless.

The disorganized electrical activity in atrial fibrillation typically originates at the root of the pulmonary veins.

The majority of treatments provided to individuals with sickle cell disease are supportive measures that have limited impact on the underlying pathophysiology of the condition.

Currently, the only approved therapy that can modify the disease is Hydroxyurea. This medication is believed to function by increasing the levels of fetal hemoglobin, which in turn decreases the concentration of HbS within the cells and reduces the abnormal hemoglobin tendency to form polymers.

Hydroxyurea is currently authorized for use in adult patients who experience recurrent moderate-to-severe painful crises (at least three in the past 12 months). Its approval is specifically for reducing the frequency of these painful episodes and the need for blood transfusions.

Adrenaline is the most crucial drug in treating anaphylaxis. It is essential to be aware of the appropriate dosage and administration method for all age groups. Additionally, high flow oxygen should be administered, as mentioned in the question stem. While there are other drugs that should be given, they are considered less important than adrenaline. These include IV fluid challenge, slow administration of chlorpheniramine (either IM or IV), slow administration of hydrocortisone (particularly in individuals with asthma), and the consideration of nebulized salbutamol or ipratropium for wheezing individuals (especially those with known asthma).

Further Reading:

Anaphylaxis is a severe and life-threatening hypersensitivity reaction that can have sudden onset and progression. It is characterized by skin or mucosal changes and can lead to life-threatening airway, breathing, or circulatory problems. Anaphylaxis can be allergic or non-allergic in nature.

In allergic anaphylaxis, there is an immediate hypersensitivity reaction where an antigen stimulates the production of IgE antibodies. These antibodies bind to mast cells and basophils. Upon re-exposure to the antigen, the IgE-covered cells release histamine and other inflammatory mediators, causing smooth muscle contraction and vasodilation.

Non-allergic anaphylaxis occurs when mast cells degrade due to a non-immune mediator. The clinical outcome is the same as in allergic anaphylaxis.

The management of anaphylaxis is the same regardless of the cause. Adrenaline is the most important drug and should be administered as soon as possible. The recommended doses for adrenaline vary based on age. Other treatments include high flow oxygen and an IV fluid challenge. Corticosteroids and chlorpheniramine are no longer recommended, while non-sedating antihistamines may be considered as third-line treatment after initial stabilization of airway, breathing, and circulation.

Common causes of anaphylaxis include food (such as nuts, which is the most common cause in children), drugs, and venom (such as wasp stings). Sometimes it can be challenging to determine if a patient had a true episode of anaphylaxis. In such cases, serum tryptase levels may be measured, as they remain elevated for up to 12 hours following an acute episode of anaphylaxis.

The Resuscitation Council (UK) provides guidelines for the management of anaphylaxis, including a visual algorithm that outlines the recommended steps for treatment.
https://www.resus.org.uk/sites/default/files/2021-05/Emergency%20Treatment%20of%20Anaphylaxis%20May%202021_0.pdf

Dementia is a collection of symptoms caused by a pathological process that leads to significant cognitive impairment, surpassing what is typically expected for a person’s age. The most prevalent form of dementia is Alzheimer’s disease.

The symptoms of dementia are diverse and encompass various aspects. These include memory loss, particularly in the short-term. Additionally, individuals with dementia may experience fluctuations in mood, which are typically responsive to external stimuli and support. It is important to note that thoughts about death are infrequent in individuals with dementia.

Furthermore, changes in personality may occur as a result of dementia. Individuals may struggle to find the right words when communicating and face difficulties in completing complex tasks. In later stages, urinary incontinence may become a concern, along with a loss of appetite and subsequent weight loss. Additionally, individuals with dementia may exhibit agitation when placed in unfamiliar settings.

Overall, dementia is characterized by a range of symptoms that significantly impact cognitive functioning.

Tonsillar herniation occurs when the cerebellar tonsils are pushed through the foramen magnum. This condition is characterized by a decrease in consciousness, respiratory arrest, and flaccid paralysis.

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

The management of anaphylaxis involves several important steps. First and foremost, it is crucial to ensure proper airway management. Additionally, early administration of adrenaline is essential, preferably in the anterolateral aspect of the middle third of the thigh. Aggressive fluid resuscitation is also necessary. In severe cases, intubation may be required. However, it is important to note that the administration of chlorpheniramine and hydrocortisone should only be considered after early resuscitation has taken place.

Adrenaline is the most vital medication for treating anaphylactic reactions. It acts as an alpha-adrenergic receptor agonist, which helps reverse peripheral vasodilatation and reduce oedema. Furthermore, its beta-adrenergic effects aid in dilating the bronchial airways, increasing the force of myocardial contraction, and suppressing histamine and leukotriene release. Administering adrenaline as the first drug is crucial, and the intramuscular (IM) route is generally the most effective for most individuals.

The recommended doses of IM adrenaline for different age groups during anaphylaxis are as follows:

– Children under 6 years: 150 mcg (0.15 mL of 1:1000)
– Children aged 6-12 years: 300 mcg (0.3 mL of 1:1000)
– Children older than 12 years: 500 mcg (0.5 mL of 1:1000)
– Adults: 500 mcg (0.5 mL of 1:1000)

To prevent diffusion hypoxia, it is recommended to administer supplemental oxygen to patients for about 5 minutes after discontinuing nitrous oxide. This is important because there is a risk of developing diffusion hypoxia after the termination of nitrous oxide.

Further Reading:

Entonox® is a mixture of 50% nitrous oxide and 50% oxygen that can be used for self-administration to reduce anxiety. It can also be used alongside other anesthesia agents. However, its mechanism of action for anxiety reduction is not fully understood. The Entonox bottles are typically identified by blue and white color-coded collars, but a new standard will replace these with dark blue shoulders in the future. It is important to note that Entonox alone cannot be used as the sole maintenance agent in anesthesia.

One of the effects of nitrous oxide is the second-gas effect, where it speeds up the absorption of other inhaled anesthesia agents. Nitrous oxide enters the alveoli and diffuses into the blood, displacing nitrogen. This displacement causes the remaining alveolar gases to become more concentrated, increasing the fractional content of inhaled anesthesia gases and accelerating the uptake of volatile agents into the blood.

However, when nitrous oxide administration is stopped, it can cause diffusion hypoxia. Nitrous oxide exits the blood and diffuses back into the alveoli, while nitrogen diffuses in the opposite direction. Nitrous oxide enters the alveoli much faster than nitrogen leaves, resulting in the dilution of oxygen within the alveoli. This can lead to diffusion hypoxia, where the oxygen concentration in the alveoli is diluted, potentially causing oxygen deprivation in patients breathing air.

There are certain contraindications for using nitrous oxide, as it can expand in air-filled spaces. It should be avoided in conditions such as head injuries with intracranial air, pneumothorax, recent intraocular gas injection, and entrapped air following a recent underwater dive.

Anaemia can be categorized based on the size of red blood cells. Microcytic anaemia, characterized by a mean corpuscular volume (MCV) of less than 80 fl, can be caused by various factors such as iron deficiency, thalassaemia, anaemia of chronic disease (which can also be normocytic), sideroblastic anaemia (which can also be normocytic), lead poisoning, and aluminium toxicity (although this is now rare and mainly affects haemodialysis patients).

On the other hand, normocytic anaemia, with an MCV ranging from 80 to 100 fl, can be attributed to conditions like haemolysis, acute haemorrhage, bone marrow failure, anaemia of chronic disease (which can also be microcytic), mixed iron and folate deficiency, pregnancy, chronic renal failure, and sickle-cell disease.

Lastly, macrocytic anaemia, characterized by an MCV greater than 100 fl, can be caused by factors such as B12 deficiency, folate deficiency, hypothyroidism, reticulocytosis, liver disease, alcohol abuse, myeloproliferative disease, myelodysplastic disease, and certain drugs like methotrexate, hydroxyurea, and azathioprine.

It is important to understand the different causes of anaemia based on red cell size as this knowledge can aid in the diagnosis and management of this condition.

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.

For patients with croup, the usual dose of oral dexamethasone is 0.15mg/kg. However, if the patient cannot take it orally, an alternative option is to administer intramuscular dexamethasone at a dose of 0.6 mg/kg as a single dose.

Further Reading:

Croup, also known as laryngotracheobronchitis, is a respiratory infection that primarily affects infants and toddlers. It is characterized by a barking cough and can cause stridor (a high-pitched sound during breathing) and respiratory distress due to swelling of the larynx and excessive secretions. The majority of cases are caused by parainfluenza viruses 1 and 3. Croup is most common in children between 6 months and 3 years of age and tends to occur more frequently in the autumn.

The clinical features of croup include a barking cough that is worse at night, preceded by symptoms of an upper respiratory tract infection such as cough, runny nose, and congestion. Stridor, respiratory distress, and fever may also be present. The severity of croup can be graded using the NICE system, which categorizes it as mild, moderate, severe, or impending respiratory failure based on the presence of symptoms such as cough, stridor, sternal/intercostal recession, agitation, lethargy, and decreased level of consciousness. The Westley croup score is another commonly used tool to assess the severity of croup based on the presence of stridor, retractions, air entry, oxygen saturation levels, and level of consciousness.

In cases of severe croup with significant airway obstruction and impending respiratory failure, symptoms may include a minimal barking cough, harder-to-hear stridor, chest wall recession, fatigue, pallor or cyanosis, decreased level of consciousness, and tachycardia. A respiratory rate over 70 breaths per minute is also indicative of severe respiratory distress.

Children with moderate or severe croup, as well as those with certain risk factors such as chronic lung disease, congenital heart disease, neuromuscular disorders, immunodeficiency, age under 3 months, inadequate fluid intake, concerns about care at home, or high fever or a toxic appearance, should be admitted to the hospital. The mainstay of treatment for croup is corticosteroids, which are typically given orally. If the child is too unwell to take oral medication, inhaled budesonide or intramuscular dexamethasone may be used as alternatives. Severe cases may require high-flow oxygen and nebulized adrenaline.

When considering the differential diagnosis for acute stridor and breathing difficulty, non-infective causes such as inhaled foreign bodies

The supraspinatus muscle is a small muscle located in the upper back. It extends from the supraspinatus fossa of the scapula to the greater tubercle of the humerus. This muscle is part of the rotator cuff, along with three other muscles. The supraspinatus muscle is innervated by the suprascapular nerve, which also innervates the infraspinatus muscle. The suprascapular nerve originates from the upper trunk of the brachial plexus.

The main function of the supraspinatus muscle is to assist the deltoid muscle in abducting the arm at the shoulder joint. Specifically, it is responsible for the initial 15 degrees of arm abduction. Beyond this range, the deltoid muscle takes over as the primary abductor.

In addition to its role in arm movement, the supraspinatus muscle works together with the other rotator cuff muscles to stabilize the shoulder joint. It helps keep the humeral head in the glenoid fossa and counteracts the downward gravitational forces exerted on the shoulder joint by the weight of the arm.

One common test used to assess the supraspinatus muscle is called the empty can test. During this test, the patient is positioned either standing or sitting, with their arms raised parallel to the ground in the scapular plane. The arm is then internally rotated fully, with the thumb facing downward. The clinician applies downward pressure on either the wrists or the elbow, while the patient resists this pressure. If the patient experiences weakness, pain, or both during this resistance, it indicates a possible tear in the supraspinatus tendon or muscle, or a suprascapular nerve neuropathy.