What are common complex cases in pediatric gastroenterology, hepatology, and nutrition for 3rd-year pediatric residents?

Common Complex Pediatric Gastroenterology, Hepatology, and Nutrition Cases for 3rd-Year Pediatric Residents

Inflammatory Bowel Disease (IBD)

Pediatric Crohn's disease and ulcerative colitis represent the most prevalent complex cases, with approximately 1,000 patients transitioning to adult care annually in the UK alone, predominantly with Crohn's disease (60%). 1

Crohn's Disease Management

• Exclusive enteral nutrition (EEN) is the first-line induction therapy for pediatric Crohn's disease in children who have not completed growth, preferred over corticosteroids despite equivalent efficacy for inducing remission, due to superior safety profile and avoidance of growth suppression 1, 2
• EEN involves complete replacement of regular diet with liquid formula for 6-8 weeks to induce remission 3, 4
• Corticosteroids should be reserved for patients who cannot tolerate or fail EEN 1
• Most pediatric CD patients require immunomodulator-based maintenance therapy with thiopurines 1

Predictors Requiring Top-Down Anti-TNF Approach

Consider early biologic therapy when patients present with: 1

• Severe perianal fistulizing disease
• Severe stricturing/penetrating disease at diagnosis
• Severe growth retardation
• Panenteric disease involvement
• Persistent severe disease despite adequate induction therapy

Ulcerative Colitis Considerations

• Approximately 20% of pediatric UC patients require colectomy during childhood years 5
• Mesalamine (including topical formulations) remains first-line for mild-moderate disease 5
• Therapeutic drug monitoring and calprotectin-based treat-to-target strategies should guide escalation 5

Chronic Liver Disease and Transplant Evaluation

Children with chronic liver disease face life-threatening complications requiring systematic evaluation, with biliary atresia being the most common indication for pediatric liver transplant (contrasting with acquired disease in adults). 1, 2

Biliary Atresia

• Refer for liver transplant evaluation if total bilirubin remains between 2-6 mg/dL following Kasai portoenterostomy 1
• Immediate referral warranted if bilirubin >6 mg/dL 1
• Most common congenital indication for pediatric liver transplant 1

Indications for Transplant Evaluation

Refer when patients develop: 1

• Poor weight gain and growth failure
• Variceal hemorrhage
• Intractable ascites
• Recurrent cholangitis
• Episodes of spontaneous bacterial peritonitis
• Intractable pruritus
• Advancing encephalopathy
• Uncorrectable coagulopathy

Hepatoblastoma

• Children with nonmetastatic and otherwise unresectable hepatoblastoma should be referred for transplant evaluation at diagnosis or no later than after 2 rounds of chemotherapy 1
• PRETEXT IV disease (involving all four liver sections) or complex PRETEXT III disease requires early referral to centers with pediatric hepatobiliary surgery expertise 1
• Patients with pulmonary metastases can be considered for transplant if chest CT clears after chemotherapy or residual lesions are completely resected with tumor-free margins 1

Hepatocellular Carcinoma

• Prompt referral to transplant center should occur for children with suspected or confirmed HCC 1
• Milan criteria may not apply to pediatric patients—transplantation should be considered in absence of extrahepatic disease or gross vascular invasion, irrespective of lesion size or number 1
• 60-70% of pediatric HCC occurs in non-cirrhotic livers (opposite of adults) 1

Nutritional Complications

Children with chronic liver disease require 20-80% more calories than healthy children due to hypermetabolism and malabsorption, making aggressive nutritional support critical for transplant outcomes and neurodevelopmental prognosis. 2, 6

Assessment Methods

• Serial triceps skin fold and mid-arm circumference measurements are the most reliable anthropometric assessments in children with liver disease, as weight alone overestimates nutritional adequacy due to ascites and organomegaly 6
• Avoid relying solely on weight measurements in presence of ascites 6

IBD Nutritional Considerations

• Detailed nutritional assessment is mandatory at diagnosis and throughout disease course 7
• Growth velocity impairment and abnormal bone mineralization are hallmark complications requiring monitoring 8
• Micronutrient deficiencies (iron, vitamin D, B12, zinc) are common and require systematic screening 7

Ascites Management

Start with spironolactone (aldosterone antagonist) for clinically detectable ascites, defined as "ballotable fluid" between abdominal wall and liver surface. 1, 2

Escalation Algorithm

• First-line: Spironolactone with no-added-salt diet 1
• Loop diuretics should be used cautiously—overaggressive diuresis precipitates hepatorenal syndrome 1
• For hospitalized patients with significant ascites: intravenous albumin with or without diuretics improves response 1
• Reserve large-volume paracentesis or TIPS for ascites compromising respiratory effort or severely affecting quality of life 1, 2

Warning Signs

• Rapid ascites accumulation suggests portal/hepatic vein obstruction or bacterial peritonitis requiring immediate evaluation 1

Eosinophilic Esophagitis (EoE)

EoE is an increasingly common cause of dysphagia requiring endoscopic diagnosis with at least six biopsies from different esophageal sites. 2, 9

Management Approach

• Dietary modification with elimination diets (guided by allergist/dietitian) is primary therapy 2
• PPI trial beneficial in PPI-responsive EoE subtype 2
• Topical corticosteroids (swallowed fluticasone or budesonide) for moderate-severe disease 2

Transition Planning

Formal transition arrangements are mandatory for adolescents with IBD, coeliac disease, and chronic liver disease, as inadequate transition dramatically decreases treatment compliance and worsens prognosis. 1, 2

Key Differences Between Pediatric and Adult Care

• Pediatric coeliac diagnosis often based on serology without duodenal biopsy, whereas adults always require histological evaluation 1
• Higher use of psychological management for functional GI illness in pediatrics versus adults 1
• Pediatric endoscopy typically uses general anesthesia versus adult sedation 2

Transition Timing

• Transition should occur once patients have finished or are in later stages of puberty 1
• Patients with growth issues should transition only after growth issues are resolved 1

High-Risk Populations for Transition

Approximately 1,000 IBD patients, 61-76 liver transplant patients, and 60 patients on complex enteral/parenteral nutrition transition annually in the UK 1

Parenteral Nutrition-Associated Liver Disease (PNALD)

• Patients referred for transplant in three scenarios: combined intestinal/multivisceral transplant, isolated liver transplant approaching enteral autonomy, or isolated liver transplant after achieving enteral autonomy with persistent endstage liver disease 1
• Early isolated liver transplant outcomes were initially encouraging, but recent data suggests more complex decision-making required 1

Renal Assessment in Liver Disease

Serum creatinine alone should not be used to assess renal function in children with liver disease—use either cystatin C or the revised Schwartz Formula to estimate GFR. 1

Revised Schwartz Formula

• 0.413 × [height (cm) / sCr (mg/dL)] = GFR (mL/min/1.73 m²) 1

High-Risk Populations

• Children with tyrosinemia, primary hyperoxaluria, congenital hepatic fibrosis, and methylmalonic acidemia have significant baseline renal disease 1
• Increased susceptibility to calcineurin inhibitor toxicity in patients with ABCB1 gene polymorphisms 1