Changes in nitric oxide synthase and nitrite and nitrate serum levels in patients with or without multidrug-resistant tuberculosis undergoing the intensive phase of antituberculosis therapy

Conclusion In patients with pulmonary TB, significantly higher levels of NO activity were observed as compared with the levels in healthy individuals. In patients with recurrent TB and MDR-TB, significantly lower levels of NO indicators were observed in comparison with patients with newly diagnosed pulmonary TB. After 2months on chemotherapy, a significant decrease in iNOS activity and NO metabolites was observed in patients with pulmonary TB, but the decrease in NO indicators was manifested mostly in the newly diagnosed pulmonary TB patients and patients without MDR-TB as opposed to patients with recurrent TB and MDR-TB, which suggests lower levels of immunologic and reparative processes in such patients. Therefore, the levels of nitrites and nitrates as well as iNOS activity may serve as additional diagnostic criteria to differentiate MDR-TB from nonresistant TB in patients with relapsed and newly diagnosed TB. Easily assessed NO-related markers can also serve as predictors of treatment outcome because patients with drug-susceptible strains had lower NO output approaching levels found in controls.
Source: International Journal of Mycobacteriology - Category: Infectious Diseases Source Type: research