Tuberculosis: Guidelines Changed for Latent TB Treatment.

The U.S. Centers for Disease Control and the American Thoracic Society have issued new guidelines calling for more caution in using the two-month regimen of rifampin and pyrazinamide. The change resulted from reports of 21 cases of severe liver injury with the two-drug regimen. Five of these patients died, and 16 recovered.

The new guidelines were published in the August 31, 2001 MMWR (Morbidity and Mortality Weekly Report), volume 50, number 34, pages 733-735. We cannot summarize them because there are many special cases. For most patients, especially those who are HIV-negative, the older nine-month regimen of isoniazid (INH) should be used. The persons with HIV, the guidelines include the following:

"Available data do not suggest excessive risk for severe hepatitis associated with RIF-PZA treatment among HIV-infected persons. In a large multinational trial, HIV-infected patients treated with RIF-PZA had lower rates of serum aminotransferarase (AT) elevations than those given INH alone. The RIF-PZA regimen also was well tolerated when given twice weekly to HIV-infected persons in Zambia and Haiti. However, experience from trials may not translate to all clinical practice settings, and it may be prudent to use 9 months of daily INH for treatment of HIV-infected persons with LBTI [latent TB infection] when completion of treatment can be assured."