Prednisone for prevention of paradoxical tuberculosis-associated iris

Abstract

The article by Meintjes and colleagues (Nov. 15 issue)1 on the use of prednisone for the prevention of paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) provides evidence to improve the treatment of persons who are coinfected with tuberculosis and the human immunodeficiency virus. Nevertheless, I have concerns about the inclusion in the trial of patients with a clinical diagnosis of tuberculosis and those with positive findings on smear microscopy. Many nontuberculous mycobacteria have morphologic and structural characteristics2 that are similar to those of Mycobacterium tuberculosis and cause a cavitary tuberculosis-like disease3 that is similar to tuberculosis. A diagnosis of tuberculosis that is based on smear microscopy methods or clinical manifestations could therefore be a misdiagnosis.

In addition, although antituberculosis medications are usually not effective against nontuberculous mycobacteria, they may be an effective treatment in some patients.4 As such, the investigators’ approach of enrolling patients with a clinical diagnosis of tuberculosis who had a response to antituberculosis treatment, as a way of ensuring that patients with potentially misdiagnosed tuberculosis were excluded, may not be the best. Future studies should be restricted to patients who have positive findings on culture or molecular tests, since these provide a definitive diagnosis of tuberculosis. This could improve the validity of the trial results.