Pneumocystis jiroveci Genotypes in the Spanish Population

Abstract

This study describes the genotype distribution of Pneumocystis jiroveci in 79 respiratory samples obtained from 15 patients with acquired immunodeficiency syndrome (AIDS) with P. jiroveci pneumonia and 64 human immunodeficiency virus-negative subjects with different chronic pulmonary diseases. The genotyping was based in analysis of 2 independent genetic loci: the mitochondrial large subunit ribosomal RNA (mt LSU rRNA) fragment (assessed by direct sequencing) and the gene for dihydropteroate synthase (DHPS; assessed by restriction fragment-length polymorphism). The mt LSU rRNA analysis revealed the presence of 3 different polymorphisms for both populations. The major genotype, 85C/248C, was found to be significantly higher in patients with AIDS and P. jiroveci pneumonia than in patients with pulmonary disease. The rate of genotypes 85A/248C and 85T/248C was similar in both groups. The analysis of DHPS genotypes assesses the prevalence of its 4 possible genotypes, with 35.5% of genotypes related to sulfa resistance. The data suggest a common source of infection between both groups.

Pneumocystis jiroveciiTransmission from Immunocompetent Carriers to Infant

“…Identifi cation of P. jirovecii colonization was carried out by analyzing oropharyngeal samples with nested PCR at the gene encoding the mitochondrial large-subunit rRNA, with primers pAZ102-E and pAZ102-H in the fi rst-round amplifi cation, followed by pAZ102-X and pAZ102-Y in the second-round amplifi cation (12). Pneumocystis DNA was extracted after samples were digested with proteinase K at 56ºC by using a commercial kit (QIAGEN, Hilden, Germany).…”

“…Positive controls were bronchoalveolar lavage specimens from PcP patients; negative controls were autoclaved water in the PCR mixture in the absence of the DNA template controls. All samples that were positive according to nested PCR were sequenced; polymorphisms at nucleotide positions 85 and 248 were detected by direct sequencing (12). The nested PCR products were purifi ed by using Sephacryl S-400 columns (Amersham Pharmacia Biotech AB, Uppsala, Sweden) and reamplifi ed with ABI Prism dRhodamine Terminator Cycle Sequencing Ready Reaction Kit (PE Applied Biosystems, Foster City, CA, USA).…”

“…Moreover, coinfection with genotype 3 (85T/248C) was detected in the grandfather. In addition, P. jirovecii dihydropteroate synthase locus was analyzed in the samples from the infant and her grandparents by PCR restriction fragment-length polymorphism, as described (12). Wild dihydropteroate synthase genotype was detected in all samples.…”

“…Many terms-colonization, carriage, asymptomatic infection, and subclinical infection-have been used to describe these fi ndings. Studies have shown that persons who have underlying HIV infection or other causes of immunosuppression and those who are not immunosuppressed but have chronic lung disease may often be colonized by P. jirovecii (11)(12)(13). Further hypotheses claim that these groups may play a role in person-to-person transmission and that they may serve as reservoirs for future Pneumocystis infection in other susceptible persons; however, this hypothesis has not been proven.…”

Vertical Transmission ofPneumocystis jiroveciiin Humans

“…We can add, using the second formula shown above, that among the 6 extrapulmonary TB cases, the prevalence of M. bovis is <39.3%. Our results come from a population in a highly rural area (91.5% of the population in Mbarara district) (7), where the high prevalence of animal TB has been reported.…”