Genotyping of Pneumocystis jiroveci pneumonia in Italian AIDS patients. Clinical outcome is influenced by dihydropteroate synthase and not by internal transcribed spacer genotype.

Background: Two Pneumocystis jiroveci independent genomic regions, internal transcribed spacer (ITS) 1 and ITS2, and dihydropteroate synthase (DHPS) gene have been used for typing a cohort of HIV-infected Italian patients with P jiroveci pneumonia (PcP).

Methods: Bronchoalveolar lavage samples isolated from 207 HIV-infected adults were ITS and DHPS genotyped by DNA sequencing and by restriction fragment length polymorphism analysis, respectively. Mutant DHPS samples were cloned and ITS typed.

Assessment of immune reconstitution to Pneumocystis carinii in HIV-1 patients under different highly active antiretroviral therapy regimens.

The introduction of protease inhibitors (PIs) gave a dramatic drop in AIDS-related opportunistic events, mainly due to induced immune reconstitution. Discontinuation of prophylaxis against Pneumocystis carinii is considered safe when CD4 > 200 cells/mm(3). Ideally, we should have specific functional tests for HIV-1-related decisions.