Prevalence and time course of elevated serum levels of liver enzymes in otherwise healthy Thai infants with breast milk jaundice: a cohort study

Abstract

Background: Neonatal jaundice and elevated levels of liver enzymes are found in infants with breast milk jaundice (BMJ). Objectives: To determine the prevalence and duration of elevated serum levels of liver enzymes in Thai infants with BMJ. Methods: We conducted a prospective study of Thai infants with BMJ, excluding those with pathological causes of jaundice. We measured the serum levels of total bilirubin (TB), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and γ-glutamyl transferase (GGT); followed infants with elevated levels; and estimated the time for levels to become normal using Kaplan–Meier analysis. Results: We included 42 infants (median age: 17.5 days) with BMJ, and elevated serum levels of at least 1 enzyme were found in 27 (64%) infants. We excluded 4 (10%) infants because they did not continue to be exclusively breastfed, 17 (40%) were lost to follow-up, and 21 (50%) completed the study. We found that 19 (45%) of the 42 infants had elevated GGT, 11 (26%) had elevated ALT, and 9 (21%) each had elevated AST and ALP levels. The median time for enzyme levels to normalize was 291 days (95% confidence interval [CI], 109.8 to 472.2) for ALT, 240 days (95% CI, 139.0 to 340.9) for AST, 184 days (95% CI, 4.4 to 363.6) for ALP, 120 days (95% CI, 74.6 to 164.5) for TB, and 63 days (95% CI, 61.44 to 64.6) for GGT. Infants were otherwise healthy during the follow-up. Conclusion: The prevalence of elevated serum levels of liver enzymes in Thai infants was unexpectedly high, but the levels became normal spontaneously despite continued breastfeeding, which endorses a “watchful waiting” strategy in managing asymptomatic infants with BMJ