Free SMLE Pediatrics questions

A 5 year old boy with known asthma presents with worsening wheeze and breathlessness. Respiratory rate is 44 breaths/min and oxygen saturation 92 percent in room air, with subcostal and intercostal retractions and widespread expiratory wheeze. He speaks in short phrases. After 3 back to back nebulised salbutamol and ipratropium treatments over 1 hour he remains tachypneic and wheezy. Which is the most appropriate next step in management?

A 7-month-old girl presents in January with 3 days of coryza and cough and now noisy breathing. She has taken about half her usual feeds. Temperature is 38.3 °C, respiratory rate 58 breaths/min with subcostal and intercostal retractions and nasal flaring, and oxygen saturation is 90% on room air, with widespread wheeze and fine inspiratory crackles. Chest radiograph shows hyperinflation with no focal consolidation. What is the most appropriate management?

A 5-year-old girl has 2 days of burning on passing urine, frequency, and mild suprapubic discomfort. Her temperature is 37.0 °C and she is tolerating oral intake. There is no flank pain, costovertebral angle tenderness, or vomiting, and she has had no previous urinary infections. Urinalysis shows leukocyte esterase and nitrites positive with more than 50 white cells per high-power field. What is the most appropriate initial antibiotic?

An 11-month-old girl in day care has 3 days of rhinorrhoea and cough followed by 1 day of fever to 38.8 °C, irritability, and pulling at her right ear. Otoscopy shows a bulging, opaque, erythematous right tympanic membrane with absent mobility on pneumatic otoscopy. Middle ear fluid from tympanocentesis is sent for bacterial culture and a respiratory virus panel. Which virus is most likely to be recovered from the fluid?

A 14-year-old boy presents with 10 days of joint pain that migrated from the right knee to the left ankle and then the right elbow. He had an untreated sore throat 3 weeks ago. The left ankle is swollen and hot. There are painless subcutaneous nodules over both olecranon processes, and the electrocardiogram shows a PR interval of 0.22 seconds. Which investigation would best confirm the underlying aetiology?

A 7 year old boy with asthma remains symptomatic despite adherence and correct spacer technique on a high dose inhaled corticosteroid. He wheezes on 4 days a week and wakes at night twice a week. Skin prick tests to house dust mite and cat are negative, and serum IgE is 32 IU/mL. Spirometry shows FEV1 72 percent of predicted with 14 percent reversibility. Which is the most appropriate next addition?

A 5-year-old boy is referred after a murmur was heard at a school health check. He is asymptomatic with normal growth. There is a grade 2/6 ejection systolic murmur at the upper left sternal border with a widely split second heart sound that does not vary with respiration. Electrocardiography shows an rSR pattern in lead V1 with right axis deviation. Which of the following is the most likely diagnosis?

A 3-year-old girl has 6 months of bulky, pale, foul smelling stools. Her weight has fallen from the 50th to below the 3rd percentile. Symptoms began several months after wheat cereals were introduced. Examination shows a distended abdomen, wasted buttocks, and irritability. Total IgA is normal with a tissue transglutaminase IgA antibody level more than 10 times the upper limit of normal. Which is the most appropriate management?

A 9-month-old girl with trisomy 21 has had a weight plateau since 6 months of age, when wheat cereal was introduced, dropping from the 25th to below the 3rd percentile. Her parents describe three bulky pale stools daily. Examination shows a protuberant abdomen and wasted buttocks. Haemoglobin is 94 g/L with a mean corpuscular volume of 66 fL and ferritin 6 µg/L. Which is the most appropriate initial diagnostic test?

A 7 year old boy with type 1 diabetes has fallen from the 50th to the 10th weight percentile over 6 months, with his height velocity slowing. His HbA1c is 6.0% and his insulin requirement has decreased. He has loose stools, a distended abdomen and wasted buttocks. Haemoglobin is 10.2 g/dL, ferritin 6 µg/L and TSH 2.1 mIU/L. What is the most likely cause of his growth failure?

A 6-year-old girl has had breast development for three months, followed by an adult type body odour. She has no headaches or visual complaints. Her height has crossed from the 50th to the 90th percentile over the past year. Examination shows Tanner stage 3 breasts, Tanner stage 2 pubic hair, and no café-au-lait macules. Basal LH is 2.4 IU/L and estradiol is elevated. What is the most likely underlying cause?

A 4-year-old girl is admitted with culture-confirmed pneumococcal meningitis and is receiving ceftriaxone, vancomycin, and dexamethasone. On day 2 fundoscopy shows bilateral papilloedema, but she is alert with no focal neurological deficit, and computed tomography of the head shows no hydrocephalus, abscess, or mass effect. Her parents ask what she is most at risk of. Which is the most likely long-term complication of her illness?

A 10-year-old boy attends a pediatric cardiology clinic after completing 4 weeks of intravenous antibiotics for culture-positive infective endocarditis caused by viridans group streptococci, which followed a dental extraction performed 3 weeks before his illness. He was born with an unrepaired congenital cardiac defect detected at 6 months of age. Which unoperated congenital lesion is most commonly associated with infective endocarditis?

A 3-week-old term infant whose unvaccinated mother had a febrile illness with a fine rash and painful joints at 9 weeks of gestation is referred because the red reflex is absent bilaterally. Birth weight was 2.1 kg. There is a continuous machinery murmur below the left clavicle, bounding pulses, hepatosplenomegaly, and blue-purple non-blanching papules. Auditory brainstem response testing fails bilaterally. What is the most likely causative infection?

A 13-year-old girl has not started breast development. Her height and weight are below the 5th percentile and have tracked along that percentile since age 4. She has Tanner stage 1 breasts and pubic hair, no dysmorphic features or webbed neck, and a normal sense of smell. Bone age is delayed by 2 years and thyroid function is normal. Which is the most likely cause of her delayed puberty?

A 5-year-old boy of consanguineous parents has had four admissions for pneumonia, chronic bulky greasy foul-smelling stools since infancy, and weight below the 3rd percentile despite a good appetite. He has bilateral nasal polyps, digital clubbing, and coarse crackles at both lung bases. Sweat chloride is 92 mmol/L on two occasions and sputum culture grows Pseudomonas aeruginosa. Which is the most common long-term pulmonary complication of his underlying disease?

A 5 month old girl with weight faltering, greasy stools and recurrent chest infections has a sweat chloride of 78 mmol/L, repeated on a separate day at 82 mmol/L. Her parents are first cousins and her 4 year old brother is well. They want definitive confirmation of the diagnosis and counselling about the recurrence risk in a future pregnancy. Which is the most appropriate confirmatory test?

A 7 year old boy is referred with 8 months of nasal obstruction and loss of smell. Nasal endoscopy shows bilateral pale glistening polyps filling both middle meati. He has had 3 episodes of pneumonia in 2 years, passes bulky greasy foul smelling stools, and his weight has fallen from the 25th to the 3rd centile. There is mild digital clubbing. Which is the most helpful investigation?

A 2-year-old girl has a soft, painless swelling in the left posterior triangle of the neck, present since early infancy and now 10 by 10 cm. It is compressible and brightly transilluminates; she is afebrile with no stridor, dysphagia, or facial nerve weakness. Ultrasound shows a multiloculated cystic lesion with thin septations, and aspiration yields clear straw-colored lymphatic fluid. What is the most appropriate initial treatment?

A boy of unknown age weighs 8.9 kg. He sits steadily without support, creeps forward on hands and knees, and pulls himself up on a chair leg to stand. He picks up a raisin with a crude thumb to finger grasp, says dada repeatedly but toward every adult, and enjoys peek-a-boo. He does not cruise, wave bye-bye, or use specific words. Which age best matches this developmental profile?

A 12 year old boy with type 1 diabetes stopped his insulin during 2 days of vomiting and polyuria. He is drowsy with deep sighing respirations, heart rate 134 beats/min, blood pressure 92/56 mm Hg and capillary refill 4 seconds. Capillary glucose is 29 mmol/L, venous pH 7.09, bicarbonate 7 mmol/L, potassium 4.1 mmol/L and urine ketones 4+. Which of the following is the most appropriate initial step in management?

A 9-year-old boy is brought to the emergency department with three days of polyuria, polydipsia and 3 kg weight loss, and one day of vomiting and abdominal pain. He is drowsy but rousable, his respiratory rate is 38 breaths/min with deep unlaboured breathing, heart rate is 132 beats/min, blood pressure is 96/58 mm Hg, and his breath smells fruity. A bedside capillary glucose reads 28 mmol/L (504 mg/dL) and a bedside blood beta-hydroxybutyrate is 5.4 mmol/L. Which of the following is the most appropriate investigation to confirm the diagnosis?

A 9-year-old girl has a 6-day history of spreading skin lesions. Examination shows more than 15 erosions covered by honey-coloured crusts plus several flaccid bullae over the trunk, both arms and the chin, involving roughly 8% of body surface area. Temperature is 37.9 °C, with tender cervical lymph nodes, no mucosal involvement and no skin sloughing on gentle pressure. What is the most appropriate treatment?

A 6-month-old uncircumcised boy has a 2-day fever up to 39.2 °C and irritability. He is alert and drinking well from a bottle, with moist mucous membranes and no vomiting. A catheter urine sample shows positive nitrites and leucocyte esterase with 60 white cells per high power field, and culture has been sent. What is the most appropriate antibiotic therapy?

A 3-year-old girl is brought in 4 hours after she coughed violently while eating peanuts. She now has persistent cough and mild respiratory distress. Auscultation shows decreased breath sounds and monophonic wheeze over the right chest. Chest radiography shows hyperinflation of the right lung with mediastinal shift to the left on expiration and no radiopaque object. She is stable for a planned procedure. What is the most appropriate definitive management?

A 3-year-old boy is brought to the emergency department 6 hours after his mother witnessed him swallow a 20 halala coin. He has had no vomiting, drooling, chest pain, or refusal to eat. There is no stridor. Radiography of the neck, chest, and abdomen shows a single round radiopaque object in the gastric fundus with no double ring or halo. Which is the most appropriate management?

A 10-year-old boy presents two days after pallor, dark urine and jaundice began hours after a meal of fava beans. His maternal uncle has had identical episodes since childhood. Haemoglobin is 9.6 g/dL, reticulocytes 7%, the direct antiglobulin test is negative, and the blood film shows bite cells and Heinz bodies. He is stable and the haemoglobin is rising. Which is the most appropriate long-term therapy?

A 5-week-old boy born to consanguineous parents has jaundice since the second week of life that has deepened as breastfeeding was established. He vomits after most feeds and has gained 200 g since birth. Temperature is 38.4 °C. Examination shows hepatomegaly and bilateral lens opacities. Direct bilirubin is 118 µmol/L, and urine is positive for reducing substances with a negative glucose oxidase dipstick. Which is the most likely diagnosis?

A 9-year-old boy is much shorter than his classmates. Both parents are of average height. Height is 120 cm, below the 3rd percentile, and weight is 25 kg. He is chubby with mid-facial hypoplasia and normal body proportions. Thyroid stimulating hormone is 3.2 U/L, insulin-like growth factor 1 is 18 ng/mL (normal 67 to 405), and bone age is 6 years. Which of the following is the most likely diagnosis?

A 4-year-old girl is admitted with 2 days of reduced urine output and pallor. Six days ago she developed crampy abdominal pain and diarrhoea that became bloody, three days after eating an undercooked beef burger. Haemoglobin is 7.4 g/dL, platelets are 42 × 10⁹/L, the blood film shows schistocytes, the direct antiglobulin test is negative, and creatinine is 180 micromol/L. Which culture is most likely to identify the causative organism?

A boy born at 30 weeks of gestation weighing 1.1 kg has remained in the neonatal unit since birth. His mother tested hepatitis B surface antigen negative. He is now 4 months of chronological age, weighs 3.6 kg, is off oxygen and feeding well. His chart shows he has never received hepatitis B vaccine. Which of the following is the most appropriate action regarding his hepatitis B immunization?

A 9-year-old boy has had recurrent scleral icterus and exercise intolerance since the age of 2 years. Haemoglobin is 9.4 g/dL, reticulocytes 9%, unconjugated bilirubin 78 µmol/L, and the direct antiglobulin test is negative. The spleen is palpable 4 cm below the costal margin, and ultrasound shows multiple pigment gallstones. His father and paternal grandfather had lifelong anaemia. Splenectomy is expected to abolish haemolysis in which of the following disorders?

A term newborn develops jaundice at 12 hours. At 36 hours total bilirubin is 285 µmol/L, direct fraction 12 µmol/L, hemoglobin 118 g/L, reticulocytes 9 percent, and mean corpuscular hemoglobin concentration 375 g/L. The direct antiglobulin test is negative and the blood film shows dense round red cells without central pallor. His father had a splenectomy as a teenager for anemia. What is the most likely cause of the hyperbilirubinemia?

A 2-year-old boy has 3 days of fever, refusal to eat or drink, and drooling. His gingivae are friable, swollen and bleed on light contact, with vesicles and ulcers on the tongue, buccal mucosa and inner lips, and grouped vesicles on the vermilion border and chin. His palms, soles and buttocks are free of lesions. A Tzanck smear shows multinucleated giant cells. Which organism is the most likely cause?

A 9-month-old boy has progressive abdominal distension and passes ribbon-like stools once every 5 to 7 days, dating from the neonatal period. He first passed meconium on the third day of life. His weight has fallen from the 50th to the 3rd percentile. Digital rectal examination reveals a tight empty rectum followed by an explosive gush of liquid stool. Which is the most definitive test to confirm the diagnosis?

A 2-month-old boy has 5 days of no bowel motion, abdominal distension, and bilious vomiting. He first passed meconium on the fourth day of life and has needed suppositories since. Heart rate is 172 beats/min and capillary refill 3 seconds. Rectal examination produces an explosive gush of foul liquid stool. Radiography shows dilated bowel loops with no rectal gas. Which is the most appropriate next step in management?

A 5-week-old boy has 10 days of forceful nonbilious vomiting after feeds and has lost 300 g since birth. His heart rate is 172 beats/min, capillary refill 3 seconds, and the fontanelle is sunken. Ultrasound shows pyloric muscle thickness 4.5 mm and channel length 18 mm. Blood gas shows pH 7.52, chloride 88 mmol/L, potassium 3.0 mmol/L, and bicarbonate 34 mmol/L. What is the most appropriate initial step in management?

A 9-month-old girl has completed a 10-day course of oral cefixime for her first febrile urinary tract infection. She defervesced within 36 hours, and the catheter urine culture grew more than 100 000 CFU/mL of Escherichia coli sensitive to the prescribed antibiotic. Her serum creatinine is 24 micromol/L, and abdominal examination is normal with no palpable bladder or mass. What is the most appropriate next step in her evaluation?

A boy born at 35 weeks of gestation weighing 2.4 kg is brought at a chronological age of 2 months for routine immunization. He was discharged on day 3 of life, breastfeeds well, and today weighs 4.6 kg. He has had no apnoea, no supplemental oxygen requirement and no readmission, and his examination is normal. Which of the following is the most appropriate approach?

A 4.3 kg male infant is born at 38 weeks to a mother with poorly controlled type 2 diabetes. At 1 hour of age he has a respiratory rate of 72 breaths/min with mild grunting and oxygen saturation 92 percent in room air. He is plethoric and jittery. There is no murmur and femoral pulses are palpable. What is the most appropriate next step in management?

A 10-year-old boy with an unrepaired perimembranous ventricular septal defect has 8 days of fever up to 39.2 °C and malaise. He underwent a dental extraction 2 weeks earlier without antibiotic cover. Examination reveals a harsh pansystolic murmur louder than previously documented, splinter hemorrhages, and a spleen tip palpable 2 cm below the costal margin. Which of the following is the most important investigation to establish the diagnosis?

A 9-month-old boy born at term is brought because of pallor and increasing irritability. He remains exclusively breastfed, and no iron-fortified cereal, pureed meat, or legumes have been introduced. Examination shows pale conjunctivae and palmar creases. Hemoglobin is 8.0 g/dL, mean corpuscular volume 60 fL, red cell distribution width 18 %, reticulocyte count 1 %, and platelets 520 × 10⁹/L. What is the most likely cause of his anemia?

A 3-year-old boy has completed 5 days of fever to 39.6 °C with bilateral non-purulent conjunctival injection, cracked lips, a polymorphous rash, and swelling of both hands. C-reactive protein is 180 mg/L, erythrocyte sedimentation rate 92 mm/h, and platelets 620 × 10⁹/L. Kawasaki disease is diagnosed and intravenous immunoglobulin is planned. Which investigation is most appropriate to assess the coronary arteries, both now and during follow-up?

A 9-year-old boy is shorter than his classmates. He is well with no dysmorphic features. His height is on the 3rd percentile with a growth velocity of 5 cm per year. Bone age is 7 years, IGF-1 is low for chronological age but normal for bone age, and thyroid function and celiac serology are normal. His father grew substantially after leaving school. What is the most appropriate next step?

A 12 year old girl with systemic lupus erythematosus and biopsy proven class IV lupus nephritis has completed 6 months of induction with corticosteroids and mycophenolate mofetil. Her arthritis and rash have resolved, and the urine protein to creatinine ratio has fallen from 320 to 80 mg/mmol. Her rheumatologist plans serial testing to detect impending renal flares. Which test is most useful for monitoring her response to therapy?

A 5-day-old female infant born at term presents with lethargy, poor feeding, and a temperature of 38.5 °C. The anterior fontanelle is full. Lumbar puncture shows 850 leukocytes per microlitre with 85 percent neutrophils, glucose 1.2 mmol/L against a blood glucose of 5.0 mmol/L, and protein 2.4 g/L. Gram stain of the cerebrospinal fluid shows gram-positive cocci in chains. Which antibiotic provides the necessary coverage against this organism?

A term girl is born to first cousin parents whose first child died at 9 years of age from cystic fibrosis. At 36 hours of age she is feeding and has a soft non distended abdomen, and the newborn screen shows a markedly raised immunoreactive trypsinogen. Which is the most common initial neonatal presentation of cystic fibrosis?

A ventilated 1.4 kg infant born at 29 weeks with hyaline membrane disease deteriorates on day 2. Oxygen saturation falls from 94 to 62 percent, heart rate to 78 beats/min, and blood pressure to 32/18 mm Hg. Breath sounds are absent over the right hemithorax, the trachea is deviated to the left, and transillumination of the right chest is increased. Where should the needle be inserted for immediate decompression?

A 4-year-old boy has 10 days of puffy eyes progressing to swollen legs. Blood pressure is 96/58 mm Hg and there is pitting pedal edema with mild ascites and no rash or joint swelling. Urine dipstick shows protein 4 plus with no blood, serum albumin is 17 g/L, total cholesterol 340 mg/dL, and complement C3 is normal. What is the most effective treatment to reduce his urinary protein loss?

A 6-year-old boy with primary monosymptomatic nocturnal enuresis has been managed for 8 months with evening fluid restriction, a bedtime voiding routine, and a reward chart, but still wets 5 nights per week. He has no daytime urgency or incontinence and no constipation, and urinalysis is repeatedly negative. His mother asks when medication could be offered. At what age is oral desmopressin generally considered appropriate for isolated bedwetting?

A 5-year-old girl has a rash around the nose and mouth for 4 days. It began as small blisters that ruptured, leaving 6 erosions of 5 to 15 mm covered by thick golden-yellow crusts, with new lesions along a scratch line. She is afebrile and well, with no bullae, no mucosal ulcers and no lymphadenopathy. Two nursery classmates have similar crusted facial lesions. What is the most appropriate treatment?

A 12-month-old boy is brought for review after his mother noticed him tugging at his left ear. He has had no fever, no ear discharge and no irritability, and his growth and language milestones are appropriate. Pneumatic otoscopy of the left ear shows an amber, retracted and immobile tympanic membrane with a visible air-fluid level, with no bulging, no erythema and no perforation. Which is the most appropriate management?

A 5-year-old girl has two days of dysuria, urinary frequency, and new daytime wetting. She is afebrile at 36.9 °C, alert and tolerating oral fluids, with a soft non-tender abdomen and no costovertebral angle tenderness. She has no vomiting, no previous urinary tract infection, and a normal antenatal renal ultrasound. Urine dipstick shows positive leukocyte esterase and nitrites, and a clean-catch culture is sent. Which treatment is most appropriate?

A 10-year-old girl has a painless anterior neck swelling enlarging over 4 months. There is a firm, mobile 2 cm nodule in the right thyroid lobe and no cervical lymphadenopathy. Serum TSH is 2.1 mIU/L with a normal free T4. Ultrasound shows a solitary solid hypoechoic nodule with irregular margins and microcalcifications. Ultrasound-guided fine-needle aspiration is non-diagnostic, with insufficient follicular cells. What is the most appropriate next step in management?

A 28-year-old woman attends a preconception clinic after two pregnancies ended in stillbirth and one infant died at 3 weeks of age with cataracts, sensorineural deafness and patent ductus arteriosus. She is not currently pregnant, and her serology shows rubella immunoglobulin G negative, varicella immunoglobulin G positive, and hepatitis B surface antigen negative. Which of the following vaccines is most important to give before her next pregnancy?

A 6-year-old unvaccinated girl develops a low-grade fever and aching in both wrists, followed the next day by a pink maculopapular rash that begins on the face and spreads to the trunk and limbs within 24 hours, fading by the third day. She has tender occipital, post-auricular and posterior cervical lymph nodes. There is no conjunctivitis, no coryza, no cough and no Koplik spots. Which is the most likely diagnosis?

A 5-year-old unvaccinated girl has fever of 37.9 °C and a pink maculopapular rash that started on the face and spread to the trunk within 24 hours. She has tender enlarged occipital, posterior auricular and posterior cervical lymph nodes, and mild pain in both wrists. There are no Koplik spots, no conjunctivitis and no cough. Which schedule of vaccine doses in Saudi Arabia would have prevented this infection?

A 13 year old girl with a photosensitive malar rash, painless oral ulcers, polyarthritis of the hands and knees, and 2+ proteinuria is being evaluated for systemic lupus erythematosus. Hemoglobin is 98 g/L, white cell count 2.9 × 10⁹/L, and serum creatinine 62 µmol/L. Her antinuclear antibody is positive at 1:1280 in a homogeneous pattern and C3 is low. Which antibody is the most specific for systemic lupus erythematosus?

An 18-month-old boy is brought to the emergency department after a single generalized tonic-clonic seizure lasting 3 minutes during a febrile illness. He has had no previous seizure and his development is normal. Temperature is 39.2 °C. He is now fully alert and playful, with no neck stiffness, no rash and no focal neurologic deficit, and a bulging erythematous right tympanic membrane. What is the most appropriate management?

A 5-year-old girl presents with a 1-hour history of palpitations and mild dizziness. Her heart rate is 254 beats/min, blood pressure 98/60 mm Hg, oxygen saturation 99% in room air, and she is fully alert with warm extremities. A 12 lead electrocardiogram shows a regular narrow complex tachycardia with no discernible P waves. Intravenous access has been secured. Which of the following is the most appropriate first line intervention?

An 8-year-old boy has wet the bed nearly every night since infancy and has never been dry for 6 consecutive months. He has no daytime wetting, no urgency, no history of urinary infection, and passes a strong stream. Urinalysis shows specific gravity 1.022 and no glucose, protein, nitrites or leukocyte esterase. He has never had structured advice about fluids or toileting. What is the most appropriate initial action?

A 5-year-old boy has sudden onset palpitations and chest discomfort for 45 minutes. He is alert and talking, with a heart rate of 250 beats/min that does not vary with respiration or crying, blood pressure 96/62 mm Hg, capillary refill 2 seconds, and oxygen saturation 99% in room air. The chest is clear with no murmur or gallop. Which of the following is the most appropriate immediate investigation?

A male neonate born at 39 weeks had fetal bradycardia after placental abruption. Apgar scores are 2 and 4 at 1 and 5 minutes, and he needs positive pressure ventilation for 8 minutes. Cord arterial pH is 6.92. At 2 hours he is lethargic and hypotonic with an incomplete Moro reflex and a brief focal clonic seizure. Which intervention most reduces his risk of death or cerebral palsy?

A 9-month-old infant has 6 hours of poor feeding and lethargy. Heart rate is 250 beats/min and does not vary with stimulation, blood pressure is 50/30 mm Hg, and the extremities are mottled and cool. The rhythm strip shows a regular narrow complex tachycardia. Peripheral intravenous access has failed twice and no intraosseous access is established. Which of the following is the most appropriate immediate intervention?

A 4-month-old formula-fed girl has 4 days of intermittent non-bilious vomiting, poor feeding, and irritability, and the urine in her nappy is dark and offensive smelling. Her temperature is 38.6 °C and her weight has fallen 300 g in 2 weeks. The abdomen is soft with no palpable mass or visible peristalsis, and there is no rash or focal source of infection. Which is the most likely diagnosis?

A 3-year-old boy was admitted 5 days ago with fever of 39.6 °C, vomiting, and loin tenderness. Urine culture grew more than 100000 colony-forming units per mL of Escherichia coli and his fever resolved on intravenous antibiotics. This was his first documented urinary tract infection, serum creatinine has remained normal, blood pressure is 96/58 mm Hg, and there is no antenatal hydronephrosis. Which is the most appropriate next investigation?

A 4 year old girl was diagnosed 2 months ago with oligoarticular juvenile idiopathic arthritis affecting the right knee and left ankle. Her antinuclear antibody is positive at a titre of 1:320, rheumatoid factor is negative, and she has no eye redness, pain, photophobia or visual complaints. Her mother asks how frequently she needs slit lamp examination. Which is the most appropriate screening interval for chronic anterior uveitis?

A 6-year-old unvaccinated boy has 2 days of fever, followed by an intensely itchy rash that began on the scalp and face and spread to the chest and upper trunk. The lesions are at different stages simultaneously: red macules, papules, clear vesicles on an erythematous base and honey-coloured crusts. Several shallow ulcers are present on the soft palate. Which serological test is most likely to be positive?

A 5-year-old boy with acute lymphoblastic leukaemia is on maintenance chemotherapy and has been receiving prednisolone 2 mg/kg per day for 6 weeks. Two days ago he played with a cousin who developed a vesicular rash the following morning. He is afebrile with no rash, his lymphocyte count is 0.4 × 10⁹/L, and varicella zoster virus IgG is negative. Which of the following is the most appropriate management?

An 8-week-old infant has 1 week of cough and sweating during feeds, and his weight has fallen from the 50th to the 10th percentile. Respiratory rate is 72 breaths/min with recession and bibasal crackles. There is a grade 4/6 pansystolic murmur at the left lower sternal border and hepatomegaly. Chest radiography shows cardiomegaly with increased pulmonary vascular markings. What is the most appropriate initial pharmacologic treatment?