Table 2:

Case definition and diagnostic strategy for neonatal liver failure

For neonatal liver disease occurring in an infant 60 days old or younger, consider either differential diagnosis number 1 or number 2 Neonatal liver failure (acute pattern) is characterized by one or more of the following: serum aminotransferase (aspartate aminotransferase and alanine aminotransferase) levels extremely elevated (above 1000 U/L) coagulopathy despite vitamin K supplementation unexplained hypoglycemia serum conjugated bilirubin levels elevated, but jaundice may not be prominent Neonatal liver failure (chronic pattern) is characterized by one or more of the following: serum albumin levels low, normal or subnormal serum aminotransferase (aspartate aminotransferase and alanine aminotransferase) levels normal or mildly elevated coagulopathy despite vitamin K supplementation serum conjugated bilirubin levels elevated unexplained hypoglycemia abnormal liver on sonography (ultrasound)

Investigations relating to differential diagnoses serological studies for herpes simplex, cytomegalovirus, enteric viruses (echoviruses, coxsackieviruses) and parvovirus B19 (relating to congenital infections) serum gamma-glutamyltranspeptidase normal (relating to inborn errors of bile acid synthesis and progressive familial intrahepatic cholestasis types 1 and 2) serum amino acids profile (relating to hereditary tyrosinemia type 1) urinary succinylacetone (relating to hereditary tyrosinemia type 1) serum-alpha fetoprotein (relating to hereditary tyrosinemia type 1) magnetic resonance imaging of abdomen (consistent with increased iron in liver and pancreas but not in spleen) (relating to perinatal hemochromatosis and other disorders causing iron overload) serum ferritin level elevated, typically above 1000 g/L (if above 20,000 g/L, consider erythrophagocytic syndrome to be an alternative diagnosis) (relating to perinatal hemochromatosis) histopathology (salivary gland biopsy or liver biopsy are not obligatory if hazardous to obtain) shows an iron overload or other process (relating to perinatal hemochromatosis and other etiologies) serum lactate to pyruvate ratio and urinary organic acids (relating to mitochondrial disorders)] sweat chloride in older infants (relating to cystic fibrosis) length of time receiving total parenteral nutrition (relating to total parenteral nutrition cholestasis)