Abstract

Objective: This study aimed to determine the incidence of hepatotoxicity in patients receiving latent tuberculosis infection (LTBI) prophylaxis and to evaluate the independent roles of baseline biochemical markers in predicting hepatotoxicity.

Methods: This retrospective cohort study included 613 adults who received prophylactic treatment for LTBI at the Tuberculosis Control Unit of the Karabük Provincial Health Directorate, Türkiye, between January 1, 2018, and December 31, 2024. Demographic characteristics, clinical indications, and baseline laboratory parameters, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), total bilirubin, glucose, and lipid profile, were evaluated. Univariate and multivariable logistic regression analyses were performed to identify independent predictors of hepatotoxicity occurring within the first month of treatment.

Results: Hepatotoxicity developed in 39 patients (6.3%) during the first month of treatment. In the univariate analysis, hepatotoxicity was significantly associated with nationality (p=0.03), whereas age group showed a borderline association (p=0.06); no significant association was observed with sex. Baseline ALT, AST, ALP, GGT, and bilirubin levels were significantly higher among patients who developed hepatotoxicity (all p<0.05). In the multivariable analysis, baseline ALT (OR 1.04), ALP (OR 1.01), age ≥41 years (OR 2.16), and total bilirubin (OR 5.00) were identified as independent predictors of hepatotoxicity. The model demonstrated a good fit to the data (Hosmer-Lemeshow p=0.415). The area under the curve (AUC) was 0.780 (95% CI 0.707–0.853).

Conclusion: Baseline ALT, ALP, and total bilirubin levels, together with age ≥41 years, were independent predictors of early hepatotoxicity during LTBI prophylaxis. These findings suggest that these parameters may contribute to pretreatment assessment of hepatotoxicity risk and the development of individualized monitoring strategies.