You will be presented with 8 clinical scenarios of children with vomiting.
For each, interpret the clinical and diagnostic data and provide: 1) Diagnosis, 2) Any other test, 3) What to do next, 4) Follow-up plan.
Case 1
3-week-old male with progressive projectile non-bilious vomiting after feeds. Hungry and irritable. Palpable olive in RUQ.
Serum Sodium
132 mEq/L (low)
Serum Potassium
2.9 mEq/L (low)
Serum Chloride
82 mEq/L (low)
ABG pH
7.52 (alkalosis)
Ultrasound abdomen
Pyloric muscle thickness 5 mm, channel length 20 mm
1️⃣ Diagnosis: (Write your answer below)
2️⃣ Any other test: (Write your answer below)
3️⃣ What to do next: (Write your answer below)
4️⃣ Follow-up plan: (Write your answer below)
✅ Model Answer:
• Diagnosis: Hypertrophic pyloric stenosis — projectile vomiting, palpable olive, hypochloremic metabolic alkalosis, ultrasound shows thickened pylorus.
• Any other test: Electrolytes (already done), renal function, pre-op labs.
• What to do next: Correct dehydration and electrolytes (IV 0.9% saline + KCl). Surgical consult for pyloromyotomy.
• Follow-up plan: Post-op feeding advancement, monitor weight gain, wound care.
Case 2
2-day-old newborn with bilious vomiting, abdominal distention. No stool passed. Lethargic.
Abdominal X-ray
Double-bubble sign with distal gas
WBC
18,000 (elevated)
CRP
15 mg/L (elevated)
Upper GI series
Abnormal duodenal position (corkscrew)
1️⃣ Diagnosis: (Write your answer below)
2️⃣ Any other test: (Write your answer below)
3️⃣ What to do next: (Write your answer below)
4️⃣ Follow-up plan: (Write your answer below)
✅ Model Answer:
• Diagnosis: Malrotation with midgut volvulus — bilious vomiting, double-bubble, corkscrew sign. Surgical emergency.
• Any other test: Complete blood count (done), electrolytes, renal function, lactate (assess bowel ischemia).
• What to do next: Emergent surgical consult, NPO, NG decompression, IV fluids, antibiotics. Ladd procedure.
• Follow-up plan: Post-op feeding, monitor for short bowel if necrosis, serial abdominal exams.
Case 3
9-year-old with recurrent episodes of severe vomiting lasting 12-24 hours, occurring every 6-8 weeks. Normal health between episodes. Family history of migraines.
CBC/CRP
Normal
Abdominal ultrasound
Normal
Upper GI series
Normal
Neurologic exam
Normal
1️⃣ Diagnosis: (Write your answer below)
2️⃣ Any other test: (Write your answer below)
3️⃣ What to do next: (Write your answer below)
4️⃣ Follow-up plan: (Write your answer below)
✅ Model Answer:
• Diagnosis: Cyclic vomiting syndrome (CVS) — stereotypical episodes, normal interictal period, migraine family history.
• Any other test: Metabolic workup (ammonia, lactate, urine organic acids), EEG (if seizures suspected).
• What to do next: Prophylaxis: amitriptyline, cyproheptadine, or topiramate. Acute: ondansetron, IV fluids.
• Follow-up plan: Monitor frequency/severity, adjust prophylaxis, avoid triggers. Long-term: many outgrow, but may develop migraines.
Case 4
6-year-old with morning vomiting (projectile), headache, and blurred vision. Fundoscopy shows papilledema.
CT Head
Posterior fossa mass (cerebellar)
MRI Brain
Cerebellar mass with hydrocephalus
Serum Electrolytes
Normal
CBC
Normal
1️⃣ Diagnosis: (Write your answer below)
2️⃣ Any other test: (Write your answer below)
3️⃣ What to do next: (Write your answer below)
4️⃣ Follow-up plan: (Write your answer below)
✅ Model Answer:
• Diagnosis: Increased intracranial pressure due to posterior fossa tumor (medulloblastoma/astrocytoma) — morning vomiting, headache, papilledema.
• Any other test: Pediatric neurosurgery consult, consider CSF cytology if safe, histopathology.
• What to do next: Urgent neurosurgical evaluation. Dexamethasone for edema. Surgical resection or biopsy.
• Follow-up plan: Monitor neurologic status, manage hydrocephalus (VP shunt if needed), oncology follow-up.
Case 5
18-month-old with intermittent vomiting, crying with drawing up legs, and currant jelly stool.
Abdominal X-ray
Sparse gas, possible intussusception
Ultrasound
Target sign (intussusception)
CBC/CRP
Normal
1️⃣ Diagnosis: (Write your answer below)
2️⃣ Any other test: (Write your answer below)
3️⃣ What to do next: (Write your answer below)
4️⃣ Follow-up plan: (Write your answer below)
✅ Model Answer:
• Diagnosis: Intussusception — colicky pain, vomiting, currant jelly stool, target sign on US.
• Any other test: Repeat abdominal exam, baseline labs (electrolytes, renal function).
• What to do next: Air enema reduction (diagnostic and therapeutic). If fails or peritonitis → surgery.
• Follow-up plan: Observe for recurrence, advance diet after successful reduction. Monitor for bowel perforation.
Case 6
12-year-old with vomiting, polyuria, polydipsia, weight loss, and deep breathing (Kussmaul).
Blood Glucose
450 mg/dL (elevated)
Serum Ketones
Positive
ABG pH
7.15 (acidosis)
Serum Potassium
3.2 mEq/L (low)
Urine Ketones
3+
1️⃣ Diagnosis: (Write your answer below)
2️⃣ Any other test: (Write your answer below)
3️⃣ What to do next: (Write your answer below)
4️⃣ Follow-up plan: (Write your answer below)
✅ Model Answer:
• Diagnosis: Diabetic ketoacidosis (DKA) — hyperglycemia, ketosis, acidosis, polyuria, Kussmaul breathing.
• Any other test: Serum electrolytes (already done), HbA1c, blood culture, C-peptide, autoimmune antibodies.
• What to do next: IV fluids (0.9% saline), insulin infusion, monitor potassium, glucose, pH. ICU admission if severe.
• Follow-up plan: Transition to subcutaneous insulin when acidosis resolved. Diabetes education, endocrinology follow-up.
Case 7
10-year-old with vomiting, periumbilical pain migrating to RLQ, anorexia, and fever.
✅ Model Answer:
• Diagnosis: Acute appendicitis — pain migration, RLQ tenderness, elevated WBC/CRP, ultrasound shows non-compressible appendix.
• Any other test: Surgical consult, urine pregnancy test if female, baseline electrolytes.
• What to do next: NPO, IV fluids, antibiotics (piperacillin-tazobactam or ceftriaxone+metronidazole), appendectomy.
• Follow-up plan: Monitor for surgical site infection, pain control, diet advancement.
Case 8
4-month-old with non-bilious postprandial regurgitation, arching of back, and irritability. Weight gain normal.
Weight gain
Normal (50th percentile)
Upper GI series
Normal anatomy, mild GER
pH probe
Increased acid reflux episodes
1️⃣ Diagnosis: (Write your answer below)
2️⃣ Any other test: (Write your answer below)
3️⃣ What to do next: (Write your answer below)
4️⃣ Follow-up plan: (Write your answer below)
✅ Model Answer:
• Diagnosis: Gastroesophageal reflux disease (GERD) with Sandifer syndrome — regurgitation, arching, irritability, normal weight gain.
• Any other test: None if uncomplicated; trial of PPI if severe.
• What to do next: Conservative: thickened feeds, upright positioning after feeds. Trial of PPI (omeprazole) if bothersome.
• Follow-up plan: Monitor weight, symptoms. Most resolve by 12-18 months. Reassure parents.
⚠️ Key Concept: Approach to Vomiting in Children
• Bilious vomiting: Surgical emergency (malrotation/volvulus) until proven otherwise.
• Projectile non-bilious: Pyloric stenosis (2-8 weeks, olive, hypochloremic alkalosis).
• Cyclic vomiting: Migraine variant, prophylactic amitriptyline/cyproheptadine.
• Morning vomiting + headache + papilledema: Increased ICP (tumor).
• Intussusception: Currant jelly stool, target sign on US, air enema.
• DKA: Polyuria, polydipsia, Kussmaul, hyperglycemia, ketosis.
• Appendicitis: Pain migrates to RLQ, fever, elevated WBC/CRP.
• GERD: Regurgitation, arching (Sandifer), normal growth → conservative.
🎯 Examiner Scoring Checklist
• Identifies pyloric stenosis (projectile, olive, alkalosis, US) and management