title: Short Communication: Diagnosis of Pneumocystis jirovecii Pneumonia by Detection of DNA in Blood and Oropharyngeal Wash, Compared with Sputum.
abstract: Molecular diagnostic methods on lower respiratory specimens for Pneumocystis pneumonia (PCP) are recommended, but specimens can be difficult to obtain. This study examined the diagnostic use of PCP polymerase chain reaction (PCR) on oropharyngeal wash (OPW) and blood versus sputum (spontaneous and induced) to find faster, simpler, and less invasive diagnostic methods. We prospectively recruited consenting adults with symptoms consistent with PCP. Real-time PCR targeted the Pneumocystis mitochondrial large subunit ribosomal RNA gene, using the aforementioned specimens. Clinical data were collected from routine records. Forty-five participants provided 45 sputa, 31 OPW, and 41 blood samples. Median age was 39 years and 41 (91%) were male, with median CD4 count being 64 cells/μL. Sputum PCR was positive in 27/45 (60%) participants. Comparative sensitivity of OPW was 9/19 (47%, 95% confidence interval [CI] 23-71) and blood 12/24 (50%, 95% CI 29-71) participants, both with specificity 100%. Including only samples obtained ≤2 days after start of treatment, sensitivity of OPW was 80% (8/10, 95% CI 51-100), that of blood was 57% (8/14, 95% CI 29-86), and that of combined tests was 88% (14/16, 95% CI 70-100). In 14/16 individuals with PCP and specimens obtained ≤2 days after start of treatment, diagnosis was possible using nonrespiratory samples. Despite moderate sensitivity of individual tests, combined PCP PCR on early blood and OPW specimens had high sensitivity and could reduce the need for invasive procedures. There were no false-positive results on nonrespiratory samples. Sampling and laboratory methods use routine technology and so require few additional resources.
authors.affiliation: 1 Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital , Manchester, United Kingdom .
authors.forename: Clare
authors.initials: C
authors.lastname: van Halsema
authors.affiliation: 1 Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital , Manchester, United Kingdom .
authors.forename: Leann
authors.initials: L
authors.lastname: Johnson
authors.affiliation: 1 Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital , Manchester, United Kingdom .
authors.forename: Joanne
authors.initials: J
authors.lastname: Baxter
authors.affiliation: 1 Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital , Manchester, United Kingdom .
authors.forename: Sam
authors.initials: S
authors.lastname: Douthwaite
authors.affiliation: 1 Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital , Manchester, United Kingdom .
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Clowes
authors.affiliation: 2 Department of Virology, Central Manchester NHS Foundation Trust, Public Health England , Manchester, United Kingdom .
authors.forename: Malcolm
authors.initials: M
authors.lastname: Guiver
authors.affiliation: 1 Monsall Unit, Department of Infectious Diseases and Tropical Medicine, North Manchester General Hospital , Manchester, United Kingdom .
authors.forename: Andrew
authors.initials: A
authors.lastname: Ustianowski
mesh_terms: D000328:Adult; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D004271:DNA, Fungal / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000235:genetics; D025202:Molecular Diagnostic Techniques; D045363:Pneumocystis carinii / Q000235:genetics*; D011020:Pneumonia, Pneumocystis / Q000175:diagnosis*; D016133:Polymerase Chain Reaction / Q000379:methods; D011446:Prospective Studies; D012331:RNA, Fungal / Q000097:blood*; D012335:RNA, Ribosomal / Q000097:blood* / Q000235:genetics; D054658:Ribosome Subunits, Large / Q000235:genetics; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology*
chemical_list: D004271:DNA, Fungal; D012331:RNA, Fungal; D012335:RNA, Ribosomal