Objective:

To examine the association between alanine aminotransferase (ALT) elevation and Epstein–Barr virus (EBV) DNA load, age, and sex in hospitalized children with infectious mononucleosis.

Approach:

• Study Design: Single-center retrospective cross-sectional study of 365 children hospitalized with EBV-associated infectious mononucleosis.
• Data Analysis: Multivariable linear regression evaluated the association between EBV DNA load and ALT levels; multivariable logistic regression assessed factors associated with ALT elevation.
• Age Stratification: Patients were grouped by age: <3, 3–6, and ≥6 years, with interaction analyses to examine differences across age groups.

Key Findings:

• Higher EBV DNA load was associated with higher ALT levels, with a 38% increase in ALT for each 10-fold increase in EBV DNA (adjusted β = 0.32, 95% CI: 0.24–0.41; P < 0.001).
• Older age groups had higher odds of ALT elevation: adjusted odds ratio of 2.08 (95% CI: 1.15–3.74) for ages 3–6 years and 5.89 (95% CI: 3.04–11.42) for ages ≥6 years compared to <3 years.
• Male sex was associated with lower odds of ALT elevation (adjusted odds ratio: 0.29, 95% CI: 0.17–0.51).

Interpretation:

Higher EBV DNA load, older age, and female sex were associated with ALT elevation in hospitalized children with EBV-associated infectious mononucleosis.

Limitations:

• Single-center study may limit generalizability.
• Retrospective design may introduce selection bias.

Conclusion:

Findings provide insights into the factors associated with ALT elevation during initial evaluation in pediatric patients with EBV-associated infectious mononucleosis.