[FREQUENCY AND RISK FACTORS OF SEVERE LIVER DYSFUNCTION IN ISONIAZID MONO-THERAPY FOR LATENT TUBERCULOSIS INFECTION].

[Purpose] To investigate the frequency and risk factors of severe liver dysfunction in patients receiving isoniazid (INH) mono-therapy for latent tuberculosis infection (LTBI). [Objectives and Methods] A retrospective study of patients receiving INH mono-therapy for LTBI in the single medical institute in Japan. [Results] A total of 845 subjects, aged between 20 and 70 years old, were enrolled in this study. Grade 3 liver dysfunction (the highest value between AST and ALT [=M], 500 IU/L≤ and less than 1000 IU/L) was found in 1.9% (16/845) of cases. Grade 4 liver dysfunction (M≥ 1000 IU/L) was found in 1.4% (12/845) of cases. The frequency of Grade 3-4 liver dysfunction increased with age, in patients above 40 years of age. The frequency of Grade 3 and Grade 4 liver dysfunc- tion was 2.0% (4/202) and 1.0% (2/202), respectively, in patients aged between 40 and 49 years, and 2.4% (3/123) and 3.3% (4/123), respectively, in patients aged between 60 and 69 years. The following factors were associated with an increased risk of severe liver dysfunction: hepatobiliary abnormalities, consumption of alcohol 5 times or more per week before commencing INH, and abnormal high values of ALP before commencing INH. [Conclusion] Severe liver dysfunction is not rare in patients above 40 years of age, and the indication for LTBI treatment in these patients should be evaluated carefully, balancing the risk of severe liver dysfunction and the benefits of preven- tive effects.