Detection of Pneumocystis jirovecii in oral wash from immunosuppressed patients as a diagnostic tool

• Published in: PloS one 2017-03, Vol.12 (3), p.e0174012-e0174012
• Main Authors: Hviid, Cecilie Juul, Lund, Marianne, Sørensen, Allan, Ellermann-Eriksen, Svend, Jespersen, Bente, Dam, Mette Yde, Dahlerup, Jens Frederik, Benfield, Thomas, Jespersen, Sanne, Østergaard, Lars Jørgen, Laursen, Alex Lund
• Format: Article
• Language: English
• Subjects: Acquired immune deficiency syndrome; Adult; Adults; Africa, Western; AIDS; Alveoli; Amplification; Analysis; Arthritis; Assaying; Biology and Life Sciences; Blood; Blood & organ donations; Blood donors; Bronchus; CD4 antigen; Clinical microbiology; Colonization; Copy number; Denmark; Deoxyribonucleic acid; Diagnosis; DNA; DNA probes; DNA, Fungal - genetics; DNA, Fungal - isolation & purification; Etiology; Fluids; Fragmentation; Fungi; Gastroenterology; Genes; Genomics; Geriatrics; Health risk assessment; Health risks; Hepatology; HIV; HIV Infections - complications; HIV Infections - drug therapy; HIV Infections - microbiology; HIV Infections - virology; Hospitals; Human immunodeficiency virus; Humans; Immunocompromised Host - genetics; Immunocompromised hosts; Immunofluorescence; Immunotoxicology; Infectious diseases; Inflammatory bowel disease; Inflammatory bowel diseases; Inflammatory diseases; Inhibitors; Interleukin 6; Intestine; Kidney transplantation; Kidney Transplantation - adverse effects; Male; Medical diagnosis; Medicine and health sciences; Methotrexate; Microbiology; Middle Aged; Mitochondrial DNA; Nephrology; People and Places; Pneumocystis carinii - genetics; Pneumocystis carinii - immunology; Pneumocystis carinii - isolation & purification; Pneumocystis carinii - pathogenicity; Pneumocystis carinii pneumonia; Pneumonia; Pneumonia, Pneumocystis - complications; Pneumonia, Pneumocystis - diagnosis; Pneumonia, Pneumocystis - genetics; Pneumonia, Pneumocystis - microbiology; Polymerase chain reaction; Research and Analysis Methods; Rheumatoid arthritis; Rheumatology; Sensitivity; Staining; Transplantation; Transplants & implants
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0174012

Diagnosis of Pneumocystis jirovecii (PJ) pneumonia ordinarily requires invasive procedures that could be avoided by PCR methodologies, if these could be designed with adequate cut-off values for confounding background carriage. We designed a novel quantitative real-time PCR assay to detect the mitochondrial large subunit rRNA gene of PJ in oral washes. To benchmark levels of PJ carriage versus infection, we tested asymptomatic immunosuppressed patients including Danish (n = 88) and West African HIV-infected (n = 142) patients, renal transplant recipients (n = 51), rheumatologic patients (n = 102), patients with inflammatory bowel diseases (n = 98), and healthy blood donors (controls, n = 50). The fungal burden in patients with PJ pneumonia (PCP, n = 7) was also investigated. Danish HIV-infected patients (with viremia/low CD4) and recent transplant recipients were at most risk of being carriers (prevalence of 23% and 16.7% respectively), whereas PJ was rarely detected among rheumatologic patients, patients with inflammatory bowel diseases, and untreated West African HIV patients. PJ was not detected among healthy controls. The fungal burden in patients with PCP fell rapidly on treatment. The quantitative PCR method described could conceivably discriminate between carriage and disease, given suitable threshold values for the former, and predict treatment efficacy by measures of the fungal burden in daily oral washes.