Bacterial pneumonia in persons infected with the human immunodeficiency virus. Pulmonary Complications of HIV Infection Study Group

N Engl J Med. 1995 Sep 28;333(13):845-51. doi: 10.1056/NEJM199509283331305.


Background: Patients with human immunodeficiency virus (HIV) infection are at increased risk for bacterial pneumonia in addition to opportunistic infection. However, the risk factors for bacterial pneumonia and its incidence in this population are not well defined.

Methods: In a multicenter, prospective, observational study, we monitored 1130 HIV-positive and 167 HIV-negative participating adults for up to 64 months for pulmonary disease. The HIV-positive group comprised 814 homosexual or bisexual men, 261 injection-drug users, and 55 female partners of HIV-infected men.

Results: There were 237 episodes of bacterial pneumonia among the HIV-positive participants (rate, 5.5 per 100 person-years), as compared with 6 episodes among the HIV-negative participants (rate, 0.9 per 100 person-years; P < 0.001). The rate of bacterial pneumonia increased with decreasing CD4 lymphocyte counts (2.3, 6.8, and 10.8 episodes per 100 person-years in the strata with more than 500, 200 to 500, and fewer than 200 cells per cubic millimeter, respectively; P < or = 0.022 for each comparison). Injection-drug users had a higher rate of bacterial pneumonia than did homosexual or bisexual men or female partners. In the stratum with the fewest CD4 lymphocytes, cigarette smoking was associated with an increased rate of pneumonia. Mortality was almost four times higher among participants with an episode of pneumonia than among the others. Prophylaxis with trimethoprim-sulfamethoxazole was associated with a 67 percent reduction in confirmed episodes of bacterial pneumonia (P = 0.007).

Conclusions: Bacterial pneumonia is more frequent in HIV-positive persons than in seronegative controls, and the risk is highest among those with CD4 lymphocyte counts below 200 per cubic millimeter and among injection-drug users.

Publication types

  • Multicenter Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • AIDS-Related Opportunistic Infections / epidemiology
  • AIDS-Related Opportunistic Infections / etiology*
  • AIDS-Related Opportunistic Infections / prevention & control
  • CD4 Lymphocyte Count
  • Case-Control Studies
  • Female
  • HIV Seronegativity
  • HIV Seropositivity / complications*
  • HIV Seropositivity / immunology
  • Humans
  • Male
  • Pneumonia, Bacterial / epidemiology
  • Pneumonia, Bacterial / etiology*
  • Pneumonia, Bacterial / prevention & control
  • Prospective Studies
  • Risk Factors
  • Smoking / adverse effects
  • Substance Abuse, Intravenous / complications
  • Trimethoprim, Sulfamethoxazole Drug Combination / therapeutic use


  • Trimethoprim, Sulfamethoxazole Drug Combination