COMAT Pediatrics Exam V2 | COMAT Pediatrics
Exam V2 | COMAT Pediatrics Exam V2
1. A 2-year-old boy is brought to the emergency department with a barking cough and
inspiratory stridor. On physical examination, he has mild intercostal retractions but remains
well-hydrated and playful. What is the most appropriate next step in management?
A. Immediate endotracheal intubation
B. Nebulized albuterol
C. Intravenous ampicillin
D. Oral dexamethasone
Correct Answer: D
Explanation: The clinical presentation is classic for Croup (laryngotracheobronchitis),
most commonly caused by parainfluenza virus. Management depends on severity; mild to
moderate cases benefit significantly from a single dose of oral dexamethasone to reduce
subglottic edema. Nebulized epinephrine is reserved for patients with stridor at rest or
significant respiratory distress.
2. An 8-month-old infant is evaluated for intermittent episodes of severe abdominal pain
where he draws his knees to his chest and cries inconsolably. Between episodes, he appears
lethargic. Stool examination reveals a ‘currant jelly’ appearance. What is the gold standard
for both diagnosis and treatment?
A. Abdominal ultrasound
,B. Computed tomography of the abdomen
C. Exploratory laparotomy
D. Air or contrast enema
Correct Answer: D
Explanation: Intussusception is the most common cause of intestinal obstruction in
children aged 6 to 36 months. While ultrasound is often the initial screening tool showing a
‘target sign,’ the air or contrast enema is considered the definitive diagnostic and
therapeutic intervention. Failure of non-operative reduction or signs of peritonitis would
necessitate surgical consultation.
3. A 4-week-old male presents with projectile, non-bilious vomiting after every feeding. On
examination, the infant appears hungry and has a palpable olive-shaped mass in the right
upper quadrant. Which of the following electrolyte abnormalities is most likely present?
A. Hyperkalemic metabolic acidosis
B. Hypochloremic, hypokalemic metabolic alkalosis
C. Hyponatremic metabolic acidosis
D. Normal electrolytes
Correct Answer: B
Explanation: Infantile hypertrophic pyloric stenosis causes persistent vomiting of gastric
contents, leading to the loss of hydrogen and chloride ions. This results in a metabolic
,alkalosis, which the body attempts to compensate for by exchanging intracellular
potassium for extracellular hydrogen, leading to hypokalemia. Fluid resuscitation and
electrolyte correction are mandatory before surgical pyloromyotomy.
4. A 14-year-old obese male presents with a dull ache in his left hip and a noticeable limp for
the past three weeks. On examination, his left hip is held in external rotation, and internal
rotation is limited. What is the most likely diagnosis?
A. Legg-Calvé-Perthes disease
B. Septic arthritis
C. Transient synovitis
D. Slipped capital femoral epiphysis (SCFE)
Correct Answer: D
Explanation: Slipped capital femoral epiphysis (SCFE) typically occurs in obese
adolescents during their growth spurt. The classic presentation involves hip or knee pain
with an antalgic limp and limited internal rotation of the hip. Legg-Calvé-Perthes usually
affects younger children (ages 4-10) and involves avascular necrosis of the femoral head.
5. A 3-day-old neonate born at 39 weeks’ gestation via normal spontaneous vaginal delivery
has developed a yellowish tint to the skin. The total bilirubin is 12 mg/dL (all indirect). The
infant is breastfeeding well and has normal wet/dirty diapers. What is the most likely cause?
A. Biliary atresia
B. Crigler-Najjar syndrome
, C. Rh incompatibility
D. Physiologic jaundice
Correct Answer: D
Explanation: Physiologic jaundice of the newborn is common due to increased red cell
turnover and immature hepatic conjugation by UGT1A1. In a healthy term infant with
bilirubin levels below phototherapy thresholds (usually >15-20 mg/dL depending on age),
reassurance and continued breastfeeding are appropriate. Direct hyperbilirubinemia
would suggest more serious pathology like biliary atresia.
6. A 4-year-old girl is brought to the clinic for a routine check-up. Her mother is concerned
because the child is not yet dry at night. The child has no history of UTIs and hits all
developmental milestones. What is the most appropriate advice?
A. Start desmopressin at bedtime
B. Initiate bed-wetting alarm therapy
C. Perform a renal ultrasound
D. Reassurance that this is normal at her age
Correct Answer: D
Explanation: Primary nocturnal enuresis is not typically diagnosed or treated until age 5
or older. Before this age, nighttime bladder control is still being established, and it is
considered a normal variation of development. Management for children over 5 starts with
behavioral modifications and alarms, while medications are reserved for refractory cases.
Exam V2 | COMAT Pediatrics Exam V2
1. A 2-year-old boy is brought to the emergency department with a barking cough and
inspiratory stridor. On physical examination, he has mild intercostal retractions but remains
well-hydrated and playful. What is the most appropriate next step in management?
A. Immediate endotracheal intubation
B. Nebulized albuterol
C. Intravenous ampicillin
D. Oral dexamethasone
Correct Answer: D
Explanation: The clinical presentation is classic for Croup (laryngotracheobronchitis),
most commonly caused by parainfluenza virus. Management depends on severity; mild to
moderate cases benefit significantly from a single dose of oral dexamethasone to reduce
subglottic edema. Nebulized epinephrine is reserved for patients with stridor at rest or
significant respiratory distress.
2. An 8-month-old infant is evaluated for intermittent episodes of severe abdominal pain
where he draws his knees to his chest and cries inconsolably. Between episodes, he appears
lethargic. Stool examination reveals a ‘currant jelly’ appearance. What is the gold standard
for both diagnosis and treatment?
A. Abdominal ultrasound
,B. Computed tomography of the abdomen
C. Exploratory laparotomy
D. Air or contrast enema
Correct Answer: D
Explanation: Intussusception is the most common cause of intestinal obstruction in
children aged 6 to 36 months. While ultrasound is often the initial screening tool showing a
‘target sign,’ the air or contrast enema is considered the definitive diagnostic and
therapeutic intervention. Failure of non-operative reduction or signs of peritonitis would
necessitate surgical consultation.
3. A 4-week-old male presents with projectile, non-bilious vomiting after every feeding. On
examination, the infant appears hungry and has a palpable olive-shaped mass in the right
upper quadrant. Which of the following electrolyte abnormalities is most likely present?
A. Hyperkalemic metabolic acidosis
B. Hypochloremic, hypokalemic metabolic alkalosis
C. Hyponatremic metabolic acidosis
D. Normal electrolytes
Correct Answer: B
Explanation: Infantile hypertrophic pyloric stenosis causes persistent vomiting of gastric
contents, leading to the loss of hydrogen and chloride ions. This results in a metabolic
,alkalosis, which the body attempts to compensate for by exchanging intracellular
potassium for extracellular hydrogen, leading to hypokalemia. Fluid resuscitation and
electrolyte correction are mandatory before surgical pyloromyotomy.
4. A 14-year-old obese male presents with a dull ache in his left hip and a noticeable limp for
the past three weeks. On examination, his left hip is held in external rotation, and internal
rotation is limited. What is the most likely diagnosis?
A. Legg-Calvé-Perthes disease
B. Septic arthritis
C. Transient synovitis
D. Slipped capital femoral epiphysis (SCFE)
Correct Answer: D
Explanation: Slipped capital femoral epiphysis (SCFE) typically occurs in obese
adolescents during their growth spurt. The classic presentation involves hip or knee pain
with an antalgic limp and limited internal rotation of the hip. Legg-Calvé-Perthes usually
affects younger children (ages 4-10) and involves avascular necrosis of the femoral head.
5. A 3-day-old neonate born at 39 weeks’ gestation via normal spontaneous vaginal delivery
has developed a yellowish tint to the skin. The total bilirubin is 12 mg/dL (all indirect). The
infant is breastfeeding well and has normal wet/dirty diapers. What is the most likely cause?
A. Biliary atresia
B. Crigler-Najjar syndrome
, C. Rh incompatibility
D. Physiologic jaundice
Correct Answer: D
Explanation: Physiologic jaundice of the newborn is common due to increased red cell
turnover and immature hepatic conjugation by UGT1A1. In a healthy term infant with
bilirubin levels below phototherapy thresholds (usually >15-20 mg/dL depending on age),
reassurance and continued breastfeeding are appropriate. Direct hyperbilirubinemia
would suggest more serious pathology like biliary atresia.
6. A 4-year-old girl is brought to the clinic for a routine check-up. Her mother is concerned
because the child is not yet dry at night. The child has no history of UTIs and hits all
developmental milestones. What is the most appropriate advice?
A. Start desmopressin at bedtime
B. Initiate bed-wetting alarm therapy
C. Perform a renal ultrasound
D. Reassurance that this is normal at her age
Correct Answer: D
Explanation: Primary nocturnal enuresis is not typically diagnosed or treated until age 5
or older. Before this age, nighttime bladder control is still being established, and it is
considered a normal variation of development. Management for children over 5 starts with
behavioral modifications and alarms, while medications are reserved for refractory cases.
