ABSTRACT
Background & objectives: The National Tuberculosis (TB) Control Programme has transitioned from thrice-weekly to daily drug treatment regimens in India. This preliminary study was conceived to compare the pharmacokinetics of rifampicin (RMP), isoniazid (INH) and pyrazinamide (PZA) in TB patients being treated with daily and thrice weekly anti-TB treatment (ATT). Methods: This prospective observational study was undertaken in 49 newly diagnosed adult TB patients receiving either daily ATT (n=22) or thrice-weekly ATT (n=27). Plasma RMP, INH and PZA were estimated by high-performance liquid chromatography. Results: The peak concentration (Cmax) of RMP was significantly higher (RMP: 8.5 ?g/ml vs. 5.5 ?g/ml; P=0.003) and Cmax of INH was significantly lower (INH: 4.8 ?g/ml vs. 10.9 ?g/ml; P<0.001) in case of daily dosing compared to thrice-weekly ATT. Cmax of drugs and doses was significantly correlated. A higher proportion of patients had subtherapeutic RMP Cmax (8.0 ?g/ml) during thrice-weekly compared to daily ATT (78% vs. 36%; P=0.004). Multiple linear regression analysis showed that Cmax of RMP was significantly influenced by the dosing rhythm, pulmonary TB and Cmax of INH and PZA by the mg/kg doses. Interpretation & conclusions: RMP concentrations were higher and INH concentrations were lower during daily ATT, suggesting that INH doses may need to be increased in case of a daily regimen. Larger studies are, however, required using higher INH doses when monitoring for adverse drug reactions and treatment outcomes.
ABSTRACT
Hepatitis E infection (HEV) in pregnant females, especially in the third trimester is associated with poor foetomaternal outcomes. However, the mechanisms of severe liver injury remain obscure. In a recent HEV outbreak in North India, six pregnant females were detected to be positive for HEV infection with concomitant hepatitis A infection in three pregnant females. None of the pregnant females were positive for hepatitis B or hepatitis C infection. The mortality was 50% in pregnant females. In an outbreak, besides, testing for hepatitis markers and understanding the pathogenesis of HEV infection in pregnancy, improving basic hygienic standards is of utmost importance.
ABSTRACT
Background & objectives: Large variability in anti-tuberculosis (TB) drug concentrations between patients is known to exist. However, limited information is available on intrapatient drug levels during the course of anti-TB treatment (ATT). This study was conducted to evaluate intrapatient variability in plasma rifampicin (RMP) and isoniazid (INH) concentrations during ATT at start of the treatment, at the end of intensive phase (IP) of ATT and at the end of ATT in adult TB patients being treated in the Revised National TB Control Programme (RNTCP). Methods: Adult TB patients (n=485), receiving thrice-weekly ATT in the RNTCP, were studied. Two-hour post-dosing concentrations of RMP and INH were determined at month 1, end of IP and end of ATT, after directly observed drug administration. Drug concentrations were estimated by high-performance liquid chromatography. Results: The median (inter-quartile range) RMP concentrations during the first month, at end of IP and end of ATT were 2.1 (0.4-5.0), 2.4 (0.6-5.5) and 2.2 (0.5-5.3) ?g/ml, respectively. The corresponding INH concentrations were 7.1 (4.2-9.9), 7.2 (3.9-10.9) and 6.7 (3.9-9.5) ?g/ml. None of the differences in drug concentrations obtained at different time points during ATT were significant. RMP and INH concentrations at different time points were significantly correlated. Age and body mass index caused significant variability in drug concentrations. Interpretation & conclusions: Plasma RMP and INH estimations in adult TB patients at two hours after drug administration remained unaltered during ATT. Clinicians can consider testing drug concentrations at any time point during ATT. These findings may assume significance in the context of therapeutic drug monitoring of anti-TB drug concentrations.