TB should be diagnosed before using a fluoroquinolone

Editor—Initial symptoms of tuberculosis are likely to be ignored by patients. Factors related to healthcare providers, however, are much more likely to cause the delay in diagnosing tuberculosis. The findings of Rodger et al help in confirming the bias of healthcare providers that resulted in delayed diagnosis of tuberculosis in white people and women.¹

Another important provider related factor that has been held responsible for delayed diagnosis of tuberculosis is inadvertent use of a fluoroquinolone as a single drug in undiagnosed tuberculosis, leading to suppression of early symptoms and delay in the diagnosis.² After the cases initially reported by us² I continue to see many such cases regularly in which the diagnosis of tuberculosis is delayed because of the indiscriminate use of fluoroquinolones.

The use of these potent broad spectrum antimicrobials is rising worldwide. Especially in developing countries these are being routinely prescribed as first line drugs for any case of fever, trivial respiratory tract infections, and minor gastrointestinal upsets. So far no warning has become associated with their use in a patient in whom the possibility of tuberculosis cannot be ruled out.

Fluoroquinolones are also precious antituberculous agents. The World Health Organization is already ringing alarm bells about multidrug resistant tuberculosis, and generic resistance against fluoroquinolone among strains of Mycobacterium tuberculosis is on the rise. Is it not time to put fluoroquinolones to a more restricted use and issue a warning about their use in conditions where the diagnosis of tuberculosis—either pulmonary or extrapulmonary—cannot be ruled out? To prevent emergence of fluoroquinolone resistance in M tuberculosis and to avoid the delay in the diagnosis of the disease caused by it, we may need to diagnose tuberculosis or rule it out before using a fluoroquinolone.