Pneumocystis Carinii - Colonization

11/13/2003

Question: Do HIV patients colonize Pneumocystis carinii (PCP) fungus?

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Unique Identifier:12517845

Authors: Nevez G. Totet A. Jounieaux V. Schmit JL. Dei-Cas E. Raccurt C.

Institution: Department of Parasitology, Mycology and Travel Medicine, University Hospital of Amiens, Jules Verne University of Picardy, 80054 Amiens, France. gnevez@yahoo.fr

Title: Pneumocystis jiroveci internal transcribed spacer types in patients colonized by the fungus and in patients with pneumocystosis from the same French geographic region.

Source: Journal of Clinical Microbiology. 41(1):181-6, 2003 Jan.

Abstract: Pneumocystis jiroveci (human-derived Pneumocystis) infections can display a broad spectrum of clinical presentations, of which pulmonary colonization with the fungus may represent an important part, occurring frequently in patients with various underlying diseases and presenting alternative diagnoses of acute pneumocystosis (Pneumocystis carinii pneumonia [PCP]). There are few data concerning the P. jiroveci genotypes involved in pulmonary colonization, whereas several genotypes responsible for PCP in immunocompromised patients have been described. In this study, P. jiroveci genotypes have retrospectively been investigated and compared in 6 colonized patients and in 11 patients with PCP who were in the same hospital. Seventeen archival bronchoalveolar lavage samples were genotyped at internal-transcribed spacer 1 (ITS1) and ITS2 of the nuclear rRNA operon. Fourteen different genotypes were identified, of which 1 was found only in colonized patients, 10 were found only in patients with PCP, and 3 were found in both patient populations. Mixed infections were diagnosed in 2 of the 6 colonized patients and in 6 of the 11 patients with PCP. The results show that similar genotypes can be responsible for PCP as well as pulmonary colonization. There is a high diversity of genotypes in colonized patients and in patients with PCP. Mixed infections may occur in these two patient populations. These shared features of P. jiroveci ITS genotypes in colonized patients and patients with PCP suggest that human populations infected by P. jiroveci, whatever the clinical manifestation, may play a role as a common reservoir for the fungus. CAS Registry/EC Number 0 (DNA, Intergenic).

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Unique Identifier:11211229

Authors: Nevez G. Guyot K. Totet A. Raccurt C. Dei-Cas E.

Institution: Department of Parasitology, Mycology and Travel Medicine, University of Picardy-University Hospital Centre, Amiens, France. gnevez@yahoo.fr

Title: Pulmonary colonisation with Pneumocystis carinii in an immunosuppressed HIV-negative patient: detection and typing of the fungus by PCR.

Source: Journal of Medical Microbiology. 50(2):198-200, 2001 Feb.

Abstract: Mostly Pneumocystis carinii isolates from patients with acute pneumocystosis (PCP) have been typed until now. This report describes the typing of P. carinii organisms obtained from an HIV-negative patient without PCP. The patient underwent a broncho-alveolar lavage (BAL) to investigate an abnormal chest X-ray. He was diagnosed with sarcoidosis. However, a low level of P. carinii organisms undetectable by microscopy was detected in BAL fluid by two subsequent nested PCR assays: one assay amplifying a portion of the mitochondrial large subunit RNA gene and a second one amplifying the internal transcribed spacers (ITS) 1 and ITS 2 of the nuclear rRNA operon. This low level of the fungus did not reflect acute PCP. Indeed, the clinical outcome was improvement despite the absence of specific treatment. The patient was considered to be only colonised by the fungus. Analysis of sequences of ITS PCR products led to identification of genotype Gg. This information constitutes the first data concerning P. carinii ITS genotype from a patient without acute PCP and HIV. This type has been described previously in AIDS patients diagnosed with PCP. These results show that PCR and ITS genotyping could represent efficient tools for the further investigation of the role played by HIV-negative patients with pulmonary colonisation in the human reservoir of P. carinii. CAS Registry/EC Number 0 (DNA, Fungal).

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Unique Identifier:9854076

Authors: Rabodonirina M. Cotte L. Boibieux A. Kaiser K. Mayencon M. Raffenot D. Trepo C. Peyramond D. Picot S.

Institution: Departement de Parasitologie et de Mycologie, Universite Claude-Bernard, Lyon, France. rabodoni@rockefeller.univ-lyon1.fr

Title: Detection of Pneumocystis carinii DNA in blood specimens from human immunodeficiency virus-infected patients by nested PCR. [Review] [23 refs]

Source: Journal of Clinical Microbiology. 37(1):127-31, 1999 Jan.

Abstract: The detection of Pneumocystis carinii DNA in blood by PCR could be useful for studying the natural history of pneumocystosis and could also be a noninvasive diagnostic method. The results of previous studies are nevertheless conflicting. In our study, we compared three commercially available DNA extraction kits (GeneReleaser, QIAamp Tissue Kit, and ReadyAmp Genomic DNA Purification System) and proteinase K and proteinase K-phenol-chloroform treatments for the extraction of P. carinii DNA from dilutions of a P. carinii f. sp. hominis cyst suspension mixed with human whole blood. A rapid and simple nested PCR protocol which amplifies a portion of the mitochondrial large-subunit rRNA gene was applied to all the extraction products. The QIAmp Tissue Kit was the most effective kit for the isolation of amplification-ready P. carinii DNA and was used with nested PCR for the testing of whole-blood specimens from 35 immunocompetent control patients and 84 human immunodeficiency virus (HIV)-infected patients investigated for pulmonary disease and/or fever. In HIV-infected patients, P. carinii DNA was detected by nested PCR in blood samples from 3 of 14 patients with microscopically proven P. carinii pneumonia, 7 of 22 patients who were considered to be colonized with P. carinii, and 9 of 48 patients who were neither infected nor colonized with P. carinii. P. carinii DNA was not detected in blood specimens from the 35 immunocompetent patients. P. carinii DNA in blood might represent viable P. carinii organisms or DNA complexes released from pulmonary phagocytes. In conclusion, P. carinii DNA may be detected in whole blood from HIV-infected patients, but the nature and the meaning of the circulating form of P. carinii remain to be established. [References: 23] CAS Registry/EC Number 0 (DNA, Fungal).

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Unique Identifier:9571740

Authors: Armbruster C. Hassl A. Kriwanek S.

Institution: 2nd Medical Department, Pulmologisches Zentrum Vienna, Austria.

Title: Pneumocystis carinii colonization in the absence of immunosuppression.

Source: Scandinavian Journal of Infectious Diseases. 29(6):591-3, 1997.

Abstract: A prospective study was undertaken to evaluate the incidence and the course of Pneumocystis carinii colonization in immunocompetent patients with severe pulmonary diseases. A further perspective was to determine the diagnostic values of different detection methods. Bronchoalveolar lavage fluid samples from 77/838 adult HIV-negative patients were examined by Diff-Quik stain, direct immunofluorescence test and polymerase chain reaction. All Diff-Quik stains were negative, but direct immunofluorescence tests and polymerase chain reactions were positive in the samples of 5 patients. The normal number of granulocytes and CD4+T- lymphocytes (median 810 cells/microliters) and normal values of immunoglobulins proved the relative competence of the immune systems of the 77 patients. Although none of these patients received any agent effective against P. carinii, none developed a P. carinii pneumonia within a 120.5-d surveillance period. Nosocomial transmission could be excluded. As the colonization with P. carinii did not result in pneumonia in immunocompetent patients, clinically silent carriers have to be assumed. In non-AIDS patients, sensitive detection methods have to be used to identify colonized persons.

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Unique Identifier:9508424

Authors: Nevez G. Jounieaux V. Linas MD. Guyot K. Leophonte P. Massip P. Schmit JL. Seguela JP. Camus D. Dei-Cas E. Raccurt C. Mazars E.

Institution: Jules Verne Univ. of Picardy, South Hospital, Amiens, France.

Title: High frequency of Pneumocystis carinii sp.f. hominis colonization in HIV-negative patients.

Source: Journal of Eukaryotic Microbiology. 44(6):36S, 1997 Nov-Dec.