Abstract
Introduction: A poor treatment response in persons with tuberculosis (TB) and HIV infection can be related to low anti-TB drug concentrations, particularly if diarrhea and malabsorption are present. Although therapeutic drug monitoring (TDM) is not routinely recommended, growing bodies of literature suggest that TDM may be a useful tool to optimize therapy.
Aims: We objected in this study to determine serum concentrations of anti-TB drugs and treatment outcomes in HIV/TB patients.
Methods: Using HPLC method, serum concentrations of izoniazid (INH), rifampin (RIF), and pyrazinamide (PZA) were determined 3-5 days after receiving medications and treatment outcomes of the patients were evaluated.
Results: Twenty two patients [median age: 35 years (rang 27-57 years), median CD4+ count: 16 cells/mm3 (range 5-444 cells/mm3)] were enrolled in the study. All patients had low or very low serum concentrations of INH and RIF, 2 h after drugs ingestion. Serum concentrations of PZA were in normal and low ranges in 5 (22.73%) and 17 (77.27%) of the patients respectively. Of 22 patients, 9 (41%) were considered cured. Five patients (22.7%) died during treatment (four of them had low or very low serum concentrations of three medications), three were lost to follow-up, three were still receiving therapy, and two had relapsed (one of them was infected with Mycobacterium Kansasii).
Conclusions: Low and very low serum concentrations of INH, RIF, and PZA and poor treatment outcomes are common among our patient. Future study in a wider patient sample over a longer follow-up period are required to explore the association of between anti-TB drug concentrations and treatment outcomes.
- © 2013 ERS
