Abstract
Background: The opportunistic fungus Pneumocystis jiroveci is a common cause of respiratory infection in immunocompromised patients. By contrast, pneumocystis pneumonia (PCP) occurs only rarely in immunocompetent individuals. Asymptomatic colonisation with P jiroveci has recently been described in patients who are either minimally immunosuppressed or who have underlying lung disorders such as bronchiectasis. We sought to determine the prevalence of asymptomatic colonisation by P jiroveci in a cohort of adult patients undergoing diagnostic bronchoscopy.
Methods: A prospective observational cohort study was performed in patients who required bronchoscopy and bronchoalveolar lavage (BAL) as part of their routine clinical assessment. All the samples underwent standard microbiological analysis and a Grocott methenamine silver stain was performed where clinically indicated to detect the presence of P jiroveci. Polymerase chain reaction for detection of P jiroveci specific DNA was also performed.
Results: Ninety three consecutive BAL fluid samples were analysed, 17 (18%) of which contained P jiroveci DNA. Of the potential predictors examined, only glucocorticoid use was significantly associated with detectable P jiroveci DNA. Eighteen patients were receiving oral glucocorticoids (equivalent to >20 mg/day prednisolone) at the time of bronchoscopy, of whom eight (44%) had detectable P jiroveci DNA. In contrast, P jiroveci was detected in only nine of 75 patients (12%) who were not receiving glucocorticoids (difference between proportions 32%, 95% CI 8 to 57; p=0.004, two tailed Fisher's exact test).
Conclusions: P jiroveci colonisation, as determined by detection of P jiroveci DNA in BAL fluid, is common in HIV negative patients with primary respiratory disorders undergoing bronchoscopy and BAL. The higher prevalence in patients receiving corticosteroids suggests that oral glucocorticoid therapy is an independent risk factor for colonisation. In contrast, underlying lung cancer or COPD did not appear to be risk factors.
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Selected References
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- Aliouat E. M., Escamilla R., Cariven C., Vieu C., Mullet C., Dei-Cas E., Prévost M. C. Surfactant changes during experimental pneumocystosis are related to Pneumocystis development. Eur Respir J. 1998 Mar;11(3):542–547. [PubMed] [Google Scholar]
- Armbruster C., Hassl A., Kriwanek S. Pneumocystis carinii colonization in the absence of immunosuppression. Scand J Infect Dis. 1997;29(6):591–593. doi: 10.3109/00365549709035900. [DOI] [PubMed] [Google Scholar]
- Calderón E. J., Regordan C., Medrano F. J., Ollero M., Varela J. M. Pneumocystis carinii infection in patients with chronic bronchial disease. Lancet. 1996 Apr 6;347(9006):977–977. doi: 10.1016/s0140-6736(96)91468-3. [DOI] [PubMed] [Google Scholar]
- Deterding R. R., Shimizu H., Fisher J. H., Shannon J. M. Regulation of surfactant protein D expression by glucocorticoids in vitro and in vivo. Am J Respir Cell Mol Biol. 1994 Jan;10(1):30–37. doi: 10.1165/ajrcmb.10.1.8292379. [DOI] [PubMed] [Google Scholar]
- Dumoulin A., Mazars E., Seguy N., Gargallo-Viola D., Vargas S., Cailliez J. C., Aliouat E. M., Wakefield A. E., Dei-Cas E. Transmission of Pneumocystis carinii disease from immunocompetent contacts of infected hosts to susceptible hosts. Eur J Clin Microbiol Infect Dis. 2000 Sep;19(9):671–678. doi: 10.1007/s100960000354. [DOI] [PubMed] [Google Scholar]
- Guo Z., Kaneshiro E. S. Phospholipid composition of Pneumocystis carinii carinii and effects of methylprednisolone immunosuppression on rat lung lipids. Infect Immun. 1995 Apr;63(4):1286–1290. doi: 10.1128/iai.63.4.1286-1290.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Henson J. W., Jalaj J. K., Walker R. W., Stover D. E., Fels A. O. Pneumocystis carinii pneumonia in patients with primary brain tumors. Arch Neurol. 1991 Apr;48(4):406–409. doi: 10.1001/archneur.1991.00530160074017. [DOI] [PubMed] [Google Scholar]
- Jacobs J. L., Libby D. M., Winters R. A., Gelmont D. M., Fried E. D., Hartman B. J., Laurence J. A cluster of Pneumocystis carinii pneumonia in adults without predisposing illnesses. N Engl J Med. 1991 Jan 24;324(4):246–250. doi: 10.1056/NEJM199101243240407. [DOI] [PubMed] [Google Scholar]
- Kovacs J. A., Gill V. J., Meshnick S., Masur H. New insights into transmission, diagnosis, and drug treatment of Pneumocystis carinii pneumonia. JAMA. 2001 Nov 21;286(19):2450–2460. doi: 10.1001/jama.286.19.2450. [DOI] [PubMed] [Google Scholar]
- Miller R. F., Ambrose H. E., Wakefield A. E. Pneumocystis carinii f. sp. hominis DNA in immunocompetent health care workers in contact with patients with P. carinii pneumonia. J Clin Microbiol. 2001 Nov;39(11):3877–3882. doi: 10.1128/JCM.39.11.3877-3882.2001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miller R. F. Pneumocystis carinii infection in non-AIDS patients. Curr Opin Infect Dis. 1999 Aug;12(4):371–377. doi: 10.1097/00001432-199908000-00011. [DOI] [PubMed] [Google Scholar]
- Miller Robert F., Ambrose Helen E., Novelli Vas, Wakefield Ann E. Probable mother-to-infant transmission of Pneumocystis carinii f. sp. hominis infection. J Clin Microbiol. 2002 Apr;40(4):1555–1557. doi: 10.1128/JCM.40.4.1555-1557.2002. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nevez G., Raccurt C., Jounieaux V., Dei-Cas E., Mazars E. Pneumocystosis versus pulmonary Pneumocystis carinii colonization in HIV-negative and HIV-positive patients. AIDS. 1999 Mar 11;13(4):535–536. doi: 10.1097/00002030-199903110-00020. [DOI] [PubMed] [Google Scholar]
- Nevez G., Raccurt C., Vincent P., Jounieaux V., Dei-Cas E. Pulmonary colonization with Pneumocystis carinii in human immunodeficiency virus-negative patients: assessing risk with blood CD4+ T cell counts. Clin Infect Dis. 1999 Nov;29(5):1331–1332. doi: 10.1086/313478. [DOI] [PubMed] [Google Scholar]
- Palmer R. J., Settnes O. P., Lodal J., Wakefield A. E. Population structure of rat-derived Pneumocystis carinii in Danish wild rats. Appl Environ Microbiol. 2000 Nov;66(11):4954–4961. doi: 10.1128/aem.66.11.4954-4961.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peters S. G., Prakash U. B. Pneumocystis carinii pneumonia. Review of 53 cases. Am J Med. 1987 Jan;82(1):73–78. doi: 10.1016/0002-9343(87)90380-9. [DOI] [PubMed] [Google Scholar]
- Saiki R. K., Scharf S., Faloona F., Mullis K. B., Horn G. T., Erlich H. A., Arnheim N. Enzymatic amplification of beta-globin genomic sequences and restriction site analysis for diagnosis of sickle cell anemia. Science. 1985 Dec 20;230(4732):1350–1354. doi: 10.1126/science.2999980. [DOI] [PubMed] [Google Scholar]
- Sing A., Roggenkamp A., Autenrieth I. B., Heesemann J. Pneumocystis carinii carriage in immunocompetent patients with primary pulmonary disorders as detected by single or nested PCR. J Clin Microbiol. 1999 Oct;37(10):3409–3410. doi: 10.1128/jcm.37.10.3409-3410.1999. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Song P., Sekhon H. S., Proskocil B., Blusztajn J. K., Mark G. P., Spindel E. R. Synthesis of acetylcholine by lung cancer. Life Sci. 2003 Mar 28;72(18-19):2159–2168. doi: 10.1016/s0024-3205(03)00078-x. [DOI] [PubMed] [Google Scholar]
- Stringer James R., Beard Charles B., Miller Robert F., Wakefield Ann E. A new name (Pneumocystis jiroveci) for Pneumocystis from humans. Emerg Infect Dis. 2002 Sep;8(9):891–896. doi: 10.3201/eid0809.020096. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tsolaki A. G., Beckers P., Wakefield A. E. Pre-AIDS era isolates of Pneumocystis carinii f. sp. hominis: high genotype similarity with contemporary isolates. J Clin Microbiol. 1998 Jan;36(1):90–93. doi: 10.1128/jcm.36.1.90-93.1998. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wakefield A. E. DNA sequences identical to Pneumocystis carinii f. sp. carinii and Pneumocystis carinii f. sp. hominis in samples of air spora. J Clin Microbiol. 1996 Jul;34(7):1754–1759. doi: 10.1128/jcm.34.7.1754-1759.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wakefield A. E., Pixley F. J., Banerji S., Sinclair K., Miller R. F., Moxon E. R., Hopkin J. M. Detection of Pneumocystis carinii with DNA amplification. Lancet. 1990 Aug 25;336(8713):451–453. doi: 10.1016/0140-6736(90)92008-6. [DOI] [PubMed] [Google Scholar]
