Empiric antituberculosis treatment: benefits for earlier diagnosis and treatment of tuberculosis.

SETTING

Tuberculosis may be diagnosed too late, especially in HIV-infected patients, with consequences on bacillus transmission and survival. Empiric antibuberculosis treatment (EATT) may be started before diagnosis of tuberculosis is confirmed. As rifampicin is a broad spectrum antibiotic, EATT including rifampicin may be effective in infections other than tuberculosis, leading to misdiagnosis.

OBJECTIVE

To define the efficiency criteria of EATT with or without rifampicin.

DESIGN

Between 1988 and 1991, 20 febrile patients with suspected tuberculosis (including 15 who were HIV-positive) were started on EATT in the absence of bacteriological or histological proof of tuberculosis. 10 patients (50%) received a 4-drug non-specific EATT including rifampicin, isoniazid, pyrazinamide and ethambutol, and 10 (50%), received a 3-drug specific EATT without rifampicin.

RESULTS

In 10 patients (50%), the diagnosis of tuberculosis was confirmed by positive cultures within a mean of 32 days (15-57 days) after the beginning of EATT (group TB 1). Of the 10 patients whose cultures remained negative, 4 (20%) became afebrile and showed improvement under EATT (group TB 2), and 6 (30%) remained febrile and did not improve (group No TB). Patients from groups TB 1 and TB 2 became afebrile within a mean of 11 days (1-54 days). This delay was not different between patients receiving specific or non-specific EATT. In patients receiving specific EATT, rifampicin was added to the initial 3-drug treatment after resolution of fever.

CONCLUSION

EATT appears to be a useful method for rapid presumptive diagnosis and treatment of tuberculosis.