What are the common causes of elevated Serum Glutamic-Oxaloacetic Transaminase (SGOT) in pediatric patients?

Common Causes of Elevated SGOT (AST) in Pediatric Patients

In pediatric populations, the most common causes of elevated SGOT include viral hepatitis (particularly Hepatitis A, which accounts for approximately 85% of acute viral hepatitis cases), chronic Hepatitis B infection, drug-induced hepatotoxicity (especially from anticonvulsants, antibiotics, and aspirin), nonalcoholic fatty liver disease in obese children, and autoimmune liver conditions including primary sclerosing cholangitis with autoimmune overlap. 1, 2

Infectious Etiologies

Viral Hepatitis

• Hepatitis A virus is the predominant cause of acute viral hepatitis in children, responsible for 85% of cases, followed by Hepatitis E (8%) and Hepatitis B (5%) 2
• Chronic Hepatitis B infection causes persistently elevated ALT/AST levels, typically with values substantially higher than 20,000 IU/mL HBV DNA in the immune active phase 1
• Hepatitis C affects an estimated 23,000-46,000 children in the United States, with persistently elevated liver enzymes indicating potential need for treatment 3
• Mycoplasma pneumoniae and HSV are important infectious triggers of Stevens-Johnson syndrome/toxic epidermal necrolysis in children, which can present with elevated transaminases; up to 50% of pediatric SJS/TEN cases are infection-related 1

Drug-Induced Hepatotoxicity

High-Risk Medications

• Anticonvulsants and antibiotics are the most commonly implicated medications causing elevated transaminases in children 1
• High-dose aspirin therapy can cause anicteric hepatitis with striking SGOT elevation, even at previously considered non-toxic doses 4
• Paracetamol and ibuprofen have unclear associations but are reported to cause hepatotoxicity; one series showed higher complication rates in children receiving ibuprofen 1
• Methotrexate combined with salicylates greatly increases the frequency of abnormal liver enzyme values 5

Metabolic and Autoimmune Conditions

Nonalcoholic Fatty Liver Disease (NAFLD)

• Elevated ALT in obese children may be related to NAFLD rather than viral infection 1
• This is an increasingly important consideration given rising pediatric obesity rates 1

Primary Sclerosing Cholangitis (PSC)

• Children with PSC demonstrate higher serum ALT/AST levels compared to adult counterparts, interpreted as evidence of a distinct disease process 1
• Autoimmune overlap syndrome (autoimmune hepatitis with PSC) is significantly more common in children than adults 1
• Mild to moderate ABCB4 (MDR3) gene defects are a likely cause of small duct PSC cases in children 1

Diagnostic Approach

Initial Laboratory Evaluation

• Complete liver panel (ALT, AST, alkaline phosphatase, bilirubin, albumin) is essential 6
• Viral hepatitis serologies including Hepatitis B and C should be performed 6
• For children with elevated transaminases, HBV DNA levels >2000 IU/mL merit further evaluation, though pediatric cases typically show substantially higher levels (>20,000 IU/mL) 1

Additional Testing Based on Clinical Context

• Gamma glutamyltranspeptidase (GGT) measurement is particularly important in children for identifying biliary disease, as alkaline phosphatase is elevated with normal bone growth 1
• Consider testing for genetic/metabolic liver disease, autoimmune hepatitis, Wilson's disease, and coinfections (HCV, HDV, HIV) depending on patient history 1
• Liver biopsy may be warranted in children with persistently elevated ALT (>1.5 times upper limit of normal) and HBV DNA >2000 IU/mL to assess inflammation grade and fibrosis stage 1

Important Clinical Pitfalls

Age-Specific Considerations

• ALT elevation thresholds differ in children compared to adults; treatment decisions should not rely solely on ALT values but include age, liver histology, comorbidities, and family history of HBV-associated cirrhosis or HCC 1
• Infections acquired during infancy are more likely to spontaneously resolve, with fibrosis tending to increase with age 3
• Children with family history of HCC may warrant treatment even with relatively mild liver disease 1

Confounding Factors

• Secondary bacterial infection, prominent biliary tree on ultrasound, and ascites are associated with increased duration of illness in acute viral hepatitis 2
• Improper use of herbal medications is associated with prolonged cholestasis in pediatric patients 2
• In obese children, it may be difficult to determine if inflammation is due to active HBV infection or NAFLD 1