Concentrações séricas de rifampicina e glicemia em pacientes com tuberculose pulmonar ativa

Abstract

Tuberculosis is a chronic disease caused by Mycobacterium tuberculosis, is considered an important public health issue in Brazil with approximately 70 to 90 thousand cases reported each year. The rates of incidences of chronic comorbidities associated with obesity increased in the last years, and, consequently, the coexistence of tuberculosis and diabetes mellitus also increase. There is an interesting interaction between these chronic diseases, as diabetes mellitus alter the immune response to infection and the pharmacokinetics of anti-tuberculosis drugs, and tuberculosis difficult the glycemic control in patients with diabetes. The aim of the study was to investigate the influence of diabetes mellitus on the serum concentrations of rifampicin in a cohort of patients under treatment with anti-tuberculosis drugs. After fasting of 12 hours, the concentrations of rifampicin, blood glucose levels, and glycated hemoglobin levels were measured at 1h after the ingestion of 600 mg of rifampicin. A total of 49 patients were included in the study and allocated in the TB group (n=36) and TB-DM group (n=13). The dose administered of rifampicin was similar in both groups, with median values of 9,82mg/kg and 10,14mg/kg in TB and TB-DM groups. The median serum concentrations of rifampicin in the intensive phase of treatment were 6,83µg/ml e 2,2µg/ml and in the continuation, were 2,75µg/ml and 2,48µg/ml, in TB and TB-DM groups. Approximately 12,25% of study patients presented rifampicin serum levels above the recommended value (8µg/ml). The concentrations of rifampicin were similar in TB and TB-DM groups in both treatment phases, but TB group present significant high levels of the drug in the acute phase of treatment. Moreover, the concentrations of rifampicin did not correlate significantly with glucose levels and glycated hemoglobin levels in both groups. Diabetes Mellitus did not provoke significant changes in serum rifampicin concentrations, but the treatment phase had a significant impact on drug levels.