RESUMO
Pneumocystis jirovecii is the cause of Pneumocystis pneumonia (PCP) in humans. Isolates of P. jirovecii obtained from patients in Harare, Zimbabwe were genotyped at the superoxide dismutase locus. High genotypic similarity to isolates of P. jirovecii obtained from patients in London, UK was observed. These data provide additional support for the hypothesis that P. jirovecii is genetically indistinguishable in isolates from geographically diverse locations.
Assuntos
Pneumocystis carinii/genética , Pneumonia por Pneumocystis/microbiologia , Superóxido Dismutase/genética , Adulto , Genótipo , Humanos , Londres , Pneumocystis carinii/enzimologia , ZimbábueRESUMO
Isolates of Pneumocystis jiroveci from sulfa-exposed and nonexposed patients from London, United Kingdom, and Harare, Zimbabwe, were genotyped. At the dihydropteroate synthase (DHPS) locus, there was evidence of selection pressure from sulfa drug exposure, and reversal of DHPS genotype ratios occurred when selection pressure was absent or was removed.
Assuntos
Micoses/microbiologia , Infecções por Pneumocystis/microbiologia , Pneumocystis/genética , Genótipo , Infecções por HIV/complicações , HIV-1 , Humanos , Londres , RNA Ribossômico/genética , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Reino Unido , ZimbábueRESUMO
Forty-seven bronchoalveolar lavage fluid samples from 16 human immunodeficiency virus (HIV)-infected patients were used to test the latency model of Pneumocystis infection in the human host. Identification of DNA sequence polymorphisms at 4 independent loci were used to genotype Pneumocystis jiroveci from the 35 samples that contained detectable P. jiroveci DNA. Eighteen of those 35 samples came from patients who did not have Pneumocystis pneumonia (PCP) and had confirmed alternative diagnoses. Seven patients had asymptomatic carriage of P. jiroveci over periods of < or = 9.5 months after an episode of PCP, and in all 7 cases, a change in genotype from that in the original episode of PCP was observed. The absence of P. jiroveci DNA in one-fourth of the 47 samples and the observed changes in genotype during asymptomatic carriage do not support the latency model of infection. Asymptomatic carriage in HIV-infected patients may play a role in transmission of P. jiroveci and may even supply a reservoir for future infections.
