Pneumococcal infections in HIV-infected adults

Bacterial pneumonia, specifically pneumococcal infection, is a frequent cause of morbidity and mortality in persons infected with human immunodeficiency virus (HIV). It causes morbidity directly and possibly progression of HIV infection. The clinical presentation and response to therapy are usually similar to that of patients without HIV infection, although radiographic presentations may be atypical. There is a higher incidence of invasive disease and extrapulmonary disease, and mortality may be increased in HIV-infected patients. HIV infection impairs the host response to pneumococcus in a variety of ways. Colonization with Streptococcus pneumoniae may be prolonged for reasons that are incompletely understood. Concern about the rising prevalence of resistant pneumococcal strains is increasing, but the clinical relevance is uncertain. At least 90% of the strains that cause invasive disease are present in the 23-valent pneumococcal vaccine. The response to vaccination declines as immunodeficiency progresses; however, the potential benefit to responders is great and the risk is minimal. Therefore, this vaccine is recommended for all HIV-infected persons.