The significance of isolated aspartate aminotransferase elevation in healthy paediatric patients.

Aim: Aspartate aminotransferase (AST) is an enzyme expressed in several organs; therefore, AST elevation may reflect outside of liver pathology. AST elevation may also be associated with macro-AST (m-AST). The aim of this study was to evaluate the long-term course of children with prolonged isolated AST elevation and the prevalence of m-AST in our cohort.

Methods: We retrospectively reviewed the medical charts of children diagnosed with prolonged isolated AST elevation and were evaluated for m-AST.

Results: Thirty-two patients were included. AST elevation persisted for a median of 66.6 months and ranged from 1.23 to 12-fold upper limit of normal (ULN). Twenty-two percent were m-AST positive and 44% had borderline levels of m-AST. A statistically significant difference was found for age at presentation between the borderline and the positive m-AST groups (31 vs. 69 months, respectively. p = 0.045). None of the patients with elevated AST developed significant liver disease.

Conclusion: We confirm the benign course of prolonged isolated AST elevation in general and m-AST in particular. A fifth of the patients with isolated AST elevation were m-AST positive. No differences have been found in AST levels between negative, borderline or positive m-AST.