Does laboratory recovery of Pneumocystis carinii always mean clinically significant disease? [14]

It was generally thought that P. carinii is unlikely to be present among HIV infected patients who are both clinically and radiologically asymptomatic. The Authors reported their 2 year study of bronchoalveloar lavage (BAL) or induced sputum (IS) specimens from 45 HIV infected or non-infected patients hospitalized at the Institute of Infectious Diseases (University La Sapinza, Rome, Italy). The results obtained demonstrate for the first time that 1. some patients with AIDS PCP recover from PCP but continue to show P. carinii in they BAL or IS without relapse, and they do not require anti-Pneumocystis treatment; 2. HIV infected but asymptomatic patients without CD4+ lymphocyte depletion or even immunocompetent individuals may have P. carinii in their sputum or BAL without developing PCP. The Authors infer that non-pathogenic strains of P. carinii may be present, but need further studies to confirm this.