Toxicity and adherence to treatment for latent tuberculosis infection in patients with hematologic malignancies

Oncohematological patients undergoing chemotherapy who have latent tuberculosis infection (LTBI) are at a high risk of developing active tuberculosis (TB). The identification and treatment of these patients can prevent LTBI progressing to active TB. This study analyzed the degree of adherence with and safety of the treatment of latent tuberculosis infection (TLTBI) in oncohematological patients undergoing antineoplastic chemotherapy. This is a retrospective study of a cohort of oncohematological patients receiving TLTBI and antineoplastic chemotherapy simultaneously, between January 2007 and June 2010. The proportions of toxicity and adherence to TLTBI in these patients were compared with a non-oncohematological control group, matched for age, sex, and year in which the TLTBI was started. In addition, a minimum 2-year follow-up was carried out for all patients. A total of 105 patients who received TLTBI were included, 21 of whom had received antineoplastic chemotherapy simultaneously. The mean age of the patients was 63 years. There were no significant baseline differences in transaminase values. The percentages of patients completing treatment were 76.2 % in the control group and 71.4 % in the oncohematological group [risk ratio (RR): 1.07, 95 % confidence interval (CI): 0.79-1.43]. The voluntary dropout proportion was similar in both groups (12.3 vs. 11.8 %, RR: 1.05, 95 % CI: 0.25-4.42). Treatment was discontinued because of toxicity in three oncohematological patients and in 11 patients from the control group (RR: 1.14; 95 % CI: 035-3.66). No patient developed TB during the follow-up period. The safety of TLTBI is not influenced by simultaneous antineoplastic chemotherapy in oncohematological patients.