The purpose of this study was to investigate dihydropteroate synthase (DHPS) mutations and their clinical context in non-HIV-infected patients with Pneumocystis pneumonia (PCP). DHPS genes in respiratory samples collected from HIV-negative patients with PCP presented between January 2008 and April 2011 were amplified by polymerase chain reaction (PCR) and sequenced. Basic clinical data from the...

Pneumocystis jirovecii colonization has been associated with non-acquired immune deficiency syndrome (AIDS) pulmonary comorbidity. We used spirometry to measure pulmonary function and analyzed oral wash specimens by quantitative polymerase chain reaction (PCR), targeting the large mitochondrial ribosomal subunit. For sensitivity control, a blinded subsample was subjected to touch-down PCRs, tar...

Pneumocystis pneumonia (PcP) is a significant cause of morbidity and mortality in immunocompromised patients. In humans, PcP is caused by the opportunistic fungal species Pneumocystis jirovecii. Progress in Pneumocystis research has been hampered by a lack of viable in vitro culture methods, which limits laboratory access to human-derived organisms for drug testing. Consequently, most basic dru...

BACKGROUND Ambient air pollution (AAP) may be associated with increased risk for Pneumocystis pneumonia (PCP). The mechanisms underlying this association remain uncertain. OBJECTIVES To determine if real-life exposures to AAP are associated with suppressed IgM antibody responses to P. jirovecii in HIV-infected (HIV+) patients with active PCP, and to determine if AAP, mediated by suppressed se...

Pneumocystis jirovecii is an uncultivable fungal pathogen responsible for Pneumocystis pneumonia (PCP) in immunocompromised patients, the physiopathology of which is only partially understood. The diversity of the Pneumocystis strains associated with acute infection has mainly been studied by Sanger sequencing techniques precluding any identification of rare genetic events (< 20% frequency). We...

BACKGROUND Humoral immunity plays an important role against Pneumocystis jirovecii infection, yet clinical and environmental factors that impact bronchoalveolar antibody responses to P. jirovecii remain uncertain. METHODS From October 2008-December 2011 we enrolled consecutive HIV-infected adults admitted to San Francisco General Hospital (SFGH) who underwent bronchoscopy for suspected Pneumo...

We describe the aetiology of community-acquired pneumonia (CAP) in HIV-infected patients, risk factors for bacterial or Pneumocystis jirovecii CAP and prognostic factors of 30-day mortality. This was a prospective observational study of 331 consecutive adult CAP cases in HIV-infected patients (January 2007 to July 2012). 128 (39%) patients had CD4(+) cell counts <200 per mm(3) and 99 (43%) ha H...

BACKGROUND Pneumocystis pneumonia (PCP) may develop as a clinical manifestation of nosocomial pneumonia by means of either reactivation of resident P. jirovecii or de novo infection. However, there have been no studies describing the clinical characteristics of hospital-onset PCP. METHODS A retrospective review of medical records was performed to identify episodes of hospital-onset PCP in a t...

Pneumocystis jirovecii is an unculturable fungus and the causative agent of Pneumocystis pneumonia, a life-threatening opportunistic infection. Although molecular diagnosis is often based on the detection of mtLSU rRNA mitochondrial gene, the number of copies of mitochondrial genes had not been investigated. We developed and optimized six real-time PCR assays in order to determine the copy numb...

UNLABELLED In the context of deciphering the metabolic strategies of the obligate pathogenic fungi in the genus Pneumocystis, the genomes of three species (P. carinii, P. murina, and P. jirovecii) were compared among themselves and with the free-living, phylogenetically related fission yeast (Schizosaccharomyces pombe). The underrepresentation of amino acid metabolism pathways compared to those...