Preventing Lung Diseases in Persons with HIV Infection

Much of the improved survival for patients with HIV infection in recent years owes to the prevention of PCP. Hence, the use of antipneumocystis agents such as trimethoprim-sulfamethoxazole, dapsone, pentamidine aerosol, and atovaquone for persons with HIV infection and CD4+ lymphocyte counts < 200 cells per microliter is a high-priority intervention.

Preventive interventions for tuberculosis also should be accorded a high priority. All HIV-infected persons should receive a tuberculin skin test, and, if the test is positive (5 mm induration), isoniazid preventive therapy should be given regardless of the CD4 + lymphocyte count. Isoniazid should also be given to all HIV-infected persons who have been exposed to a person with infectious tuberculosis regardless of the tuberculin test result. The use of isoniazid preventive therapy for nonexposed persons who are defined as anergic has not been shown to be of benefit. A combination of rifampin and pyrazinamide given for 2 months has also been shown to be effective in preventing tuberculosis in persons with HIV infection who have a positive tuberculin skin test.

It is not established whether pneumococcal vaccine reduces the rate of pneumococcal disease in persons with HIV infection. However, because of the low likelihood of adverse reactions to the vaccine, any benefit would not be offset by risk. Data from the PCHIS cohort suggest that trimethoprim-sulfamethoxazole as antipneumocystis prophylaxis decreases the frequency of pneumococcal disease, thus providing an additional benefit for this preventive intervention.

Finally, it has been shown that prophylactic administration of newer macrolide agents (clarithromycin, azithromycin) reduces the frequency of M. avium complex disease by approximately 70%. Current recommendations are that macrolide prophylaxis be given to persons with HIV infection and CD4+ counts of < 100 cells per microliter. Although less effective than the macrolides, rifabetin may also be used to prevent M. avium complex disease. Persons who are candidates for rifabutin should be carefully evaluated for tuberculosis. Rifabutin administered to a person who has undiagnosed tuberculosis would quickly result in resistance of M. tuberculosis to rifabutin and rifampin, a major antituberculosis drug.