ABP Pediatric Gastroenterology cheat sheet

Rome IV criteria for functional constipation: ≥2 of: ≤2 defecations/week, fecal incontinence ≥1/week, retentive posturing, painful/hard stools, large fecal mass, large-diameter stools; ≥1 month.

GERD in infants: regurgitation ≥2 times/day for ≥3 weeks; alarm signs (bilious vomiting, hematemesis, failure to thrive, apnea) warrant investigation.

Pediatric ulcerative colitis: bloody diarrhea, urgency, tenesmus; colonoscopy with biopsies showing continuous mucosal inflammation from rectum.

Crohn disease: skip lesions, transmural inflammation, perianal disease, granulomas; ileocolonoscopy with biopsies.

Celiac disease screening: IgA tissue transglutaminase (tTG) with total IgA; confirm with duodenal biopsies showing villous atrophy and crypt hyperplasia.

Acute pancreatitis: ≥2 of: abdominal pain, lipase >3× upper limit, imaging findings; in children, lipase is preferred over amylase.

Hirschsprung disease: delayed meconium >48h, abdominal distension, bilious vomiting; diagnosis by rectal biopsy showing absence of ganglion cells.

Eosinophilic esophagitis: dysphagia, food impaction, atopy; ≥15 eosinophils/hpf on esophageal biopsy.

Intussusception: colicky pain, currant-jelly stools, sausage-shaped mass; ultrasound shows target sign; air enema is diagnostic and therapeutic.

WHO growth charts for 0–2 years; CDC charts for 2–20 years; weight-for-length for <2 years, BMI-for-age for ≥2 years.

Failure to thrive: weight-for-age <5th percentile or crossing ≥2 major percentile lines downward.

Mid-parental height: boys = (father + mother + 13 cm)/2; girls = (father + mother − 13 cm)/2; target range ±8.5 cm.

Growth velocity: normal prepubertal 5–6 cm/year; <4 cm/year warrants evaluation.

Estimated energy requirement (EER) for infants 0–6 months: 108 kcal/kg/day; 7–12 months: 98 kcal/kg/day.

Protein requirement: 1.5 g/kg/day for 0–6 months; 1.1 g/kg/day for 7–12 months; 0.95 g/kg/day for 1–3 years.

BMI percentile categories: underweight <5th, normal 5th–<85th, overweight 85th–<95th, obese ≥95th.

Bone age delay >2 years suggests constitutional delay, hypothyroidism, growth hormone deficiency, or chronic disease.

Achalasia: dysphagia to solids and liquids, bird-beak on barium swallow, manometry shows absent peristalsis and failure of LES relaxation.

H. pylori infection: urea breath test or stool antigen for diagnosis; avoid serology in children; treatment with PPI + amoxicillin + clarithromycin or metronidazole for 14 days.

Gastroparesis: delayed gastric emptying without obstruction; diagnosed by gastric emptying scintigraphy (retention >60% at 2h or >10% at 4h).

Pyloric stenosis: nonbilious projectile vomiting at 3–6 weeks, olive-shaped mass, hypochloremic hypokalemic metabolic alkalosis; ultrasound shows pyloric thickness ≥3 mm and length ≥15 mm.

Esophageal atresia with tracheoesophageal fistula: polyhydramnios, drooling, choking with feeds; NG tube coiling in upper pouch on X-ray.

Caustic ingestion: avoid emetics and NG lavage; endoscopy within 12–24 hours for grading; corticosteroids not routinely recommended.

Gastric volvulus: acute abdominal pain, retching without vomiting, inability to pass NG tube; emergency surgery.

Celiac disease: positive tTG IgA >10× ULN with symptoms may allow diagnosis without biopsy per ESPGHAN; otherwise biopsy required.

Short bowel syndrome: resection leaving <25% of expected small bowel length; management includes parenteral nutrition, enteral feeding, and medications to reduce secretions.

Intestinal failure-associated liver disease: risk increased with prolonged PN, lack of enteral feeding, and catheter infections; use fish-oil-based lipid emulsions.

Lactose intolerance: breath hydrogen test showing rise >20 ppm after lactose load; avoid lactose or use lactase supplements.

Chronic diarrhea with malabsorption: stool fecal fat >7 g/day on 72-hour collection; sweat chloride for cystic fibrosis.

Microvillous inclusion disease: congenital diarrhea with intractable secretory diarrhea, diagnosed by electron microscopy showing microvillous inclusions.

Congenital sucrase-isomaltase deficiency: osmotic diarrhea with sucrose ingestion; diagnosis by breath hydrogen test or enzyme assay; treat with sacrosidase.

Acute pancreatitis in children: lipase >3× ULN, abdominal pain, imaging; treat with fluids, analgesia, and early enteral nutrition.

Chronic pancreatitis: calcifications on CT, pancreatic insufficiency; fecal elastase <200 µg/g suggests exocrine insufficiency.

Cystic fibrosis: sweat chloride ≥60 mmol/L diagnostic; pancreatic insufficiency in 85%; treat with pancreatic enzyme replacement (500–2500 units lipase/kg/meal).

Biliary atresia: jaundice beyond 2 weeks with direct hyperbilirubinemia, acholic stools; Kasai portoenterostomy before 60 days improves outcomes.

Choledochal cyst: abdominal pain, jaundice, mass; risk of cholangiocarcinoma; treat with excision and Roux-en-Y hepaticojejunostomy.

Gallstones in children: often pigment stones; risk factors include hemolysis, TPN, ileal resection; cholecystectomy for symptomatic stones.

Pancreatic pseudocyst: fluid collection >4 weeks after pancreatitis; drain if symptomatic or enlarging.

Neonatal cholestasis: conjugated bilirubin >1 mg/dL if total <5 mg/dL, or >20% of total; evaluate for biliary atresia, metabolic, infectious, and genetic causes.

Acute liver failure: coagulopathy (INR ≥1.5) with encephalopathy or INR ≥2.0 with or without encephalopathy; no chronic liver disease.

Wilson disease: low ceruloplasmin, elevated urinary copper, Kayser-Fleischer rings; treat with chelators (penicillamine, trientine) and zinc.

Autoimmune hepatitis: elevated transaminases, hypergammaglobulinemia, autoantibodies (ANA, anti-smooth muscle); treat with prednisone and azathioprine.

Liver transplantation: indications include acute liver failure, decompensated cirrhosis, metabolic disease; 5-year survival >80%.

Post-transplant immunosuppression: tacrolimus or cyclosporine; monitor levels; complications include rejection, infection, EBV-related PTLD.

Hepatitis B: screening with HBsAg, anti-HBc, anti-HBs; vaccination is universal; chronic infection defined as HBsAg positive >6 months.

Inflammatory bowel disease: Crohn disease with skip lesions, transmural inflammation, granulomas; ulcerative colitis continuous from rectum.

Very early-onset IBD (VEO-IBD): onset <6 years; consider genetic testing for IL-10 receptor mutations and other monogenic causes.

Eosinophilic gastroenteritis: eosinophilic infiltration of GI tract; symptoms depend on layer involved (mucosal, muscular, serosal); treat with elimination diet or corticosteroids.

Food protein-induced enterocolitis syndrome (FPIES): repetitive vomiting 1–3 hours after ingestion, diarrhea, lethargy; treat with IV fluids and avoidance of trigger.

Celiac disease is an autoimmune enteropathy triggered by gluten; associated with HLA-DQ2/DQ8.

Autoimmune enteropathy: intractable diarrhea, anti-enterocyte antibodies, associated with IPEX syndrome (FOXP3 mutation).

IgE-mediated food allergy: immediate symptoms (urticaria, anaphylaxis); diagnosis by skin prick test or specific IgE; treat with avoidance and epinephrine.

Upper endoscopy: indications include dysphagia, persistent vomiting, GI bleeding, suspected celiac disease, foreign body; contraindications include hemodynamic instability and suspected perforation.

Colonoscopy: bowel preparation with polyethylene glycol; complications include bleeding and perforation; need for anesthesia in children.

Liver biopsy: percutaneous or transjugular; contraindications include coagulopathy (INR >1.5) and thrombocytopenia (<50,000).

Wireless capsule endoscopy: for small bowel evaluation; contraindicated in suspected obstruction or stricture.

Esophageal pH monitoring: for GERD; impedance adds detection of non-acid reflux.

Therapeutic endoscopy: include variceal band ligation, sclerotherapy, foreign body removal, and stricture dilation.

Anesthesia for endoscopy: generally general anesthesia with endotracheal tube for airway protection in children.

Evidence-based medicine: use systematic reviews and randomized controlled trials; GRADE system for rating quality of evidence.

Informed consent: must include risks, benefits, alternatives; assent from minors when appropriate.

Research ethics: institutional review board (IRB) approval required for human subjects research; informed consent from parents and assent from children.

Professionalism: maintain confidentiality (HIPAA), avoid conflicts of interest, and practice cultural competence.

Quality improvement: use Plan-Do-Study-Act (PDSA) cycles; measure outcomes and processes.

Teaching: use adult learning principles; provide feedback and evaluate competence.

Board certification: maintenance of certification (MOC) includes lifelong learning and self-assessment.