EFFECT OF DIABETES MELLITUS ON RIFAMPICIN PEAK SERUM CONCENTRATION

Objective: To comparatively analyze the peak serum concentration (Cmax) of rifampicin and to determine the incidence of decreased Cmax between diabetic and non-diabetic adult pulmonary tuberculosis patients.

Methods: A cross-sectional observational study was carried out in the chest and tuberculosis (TB) department of a tertiary care hospital after the approval of the institutional ethics committee. Five millilitre (ml) of blood was withdrawn by venipuncture from each patient at a time point of 2 h post dose administration at steady state concentration (Css). The separated serum was centrifuged at a rate of 3500 rotations per minute (rpm) for a period of fifteen minutes and the resultant serum was stored at-70 ° C until analysis. Estimation of rifampicin concentration was carried out in Thermo TSQ Ultra (MS/MS) with Shimadzu 20 AD UFLC LC-MS.

Results: The mean (Standard Deviation (SD)) age of the study population was 46.8 (14.2) years. The mean serum Cmax of rifampicin was significantly less in diabetic patients with pulmonary tuberculosis (p=0.0305). Statistically, a significant difference in the incidence of a decrease in Cmax was found between diabetic and non-diabetic patients (p=0.0335). Diabetes mellitus was found to be the predominant factor that affects rifampicin Cmax.

Conclusion: In this study, an effect of diabetes mellitus (DM) on the peak serum concentration of rifampicin was observed. Patients with hyperglycemia levels had significantly reduced levels of rifampicin serum concentrations, thus showing an inversely proportional relationship between blood glucose and rifampicin serum levels.