Isoniazid-induced hepatotoxicity in latent tuberculosis patients

Latent tuberculosis infection (LTBI) is a pivotal intervention point to prevent progression to active tuberculosis. The most concerning side effect of LTBI treatment is hepatotoxicity, which may affect up to 4% of patients. The goal was to analyze a population of patients with LTBI undergoing monotherapy with isoniazid to determine incidence rate and factors associated with hepatotoxicity. We conducted a retrospective study with patients who began treatment for LTBI between January 2020 and June 2021. All data was submitted through descriptive and inferential statistical analysis; a significance level of 0.05 was assumed. A total of 273 patients were included with a median age of 53 years; 50.5% were male. The most common comorbidities were dyslipidemia (25.6%), excess weight defined as body mass index (BMI) between 25-30 kg/m² (20.5%), obesity defined as BMI over 30 kg/m² (14.7%), psoriasis (13.2%) and chronic liver disease (12.8%); 47.3% of patients were candidates for systemic immunosuppression therapy diseases. Treatment was interrupted in 24.8% of patients, with a total of 50 cases (18.3%) due to hepatotoxicity; treatment interruption occurred between the first- and twenty-third-weeks treatment. In this sample, male gender (p = 0.035), dyslipidemia (p <. 001), excess weight (p <. 001), chronic liver disease (p = 0.009) and psoriasis (p = 0.012) were all associated with development of hepatotoxicity; dyslipidemia was identified as an independent risk factor, with an odds ratio of 13.5 (95% confidence interval: 5.4-34.1). We found an abnormally high incidence of hepatotoxicity and detected dyslipidemia as a major risk factor. Further studies are required to determine other risk factors that may explain these results.