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Bateman M, Oladele R, Kolls JK. Diagnosing Pneumocystis jirovecii pneumonia: A review of current methods and novel approaches. Med Mycol 2020; 58:1015-1028. [PMID: 32400869 PMCID: PMC7657095 DOI: 10.1093/mmy/myaa024] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 03/13/2020] [Accepted: 05/07/2020] [Indexed: 12/13/2022] Open
Abstract
Pneumocystis jirovecii can cause life-threatening pneumonia in immunocompromised patients. Traditional diagnostic testing has relied on staining and direct visualization of the life-forms in bronchoalveolar lavage fluid. This method has proven insensitive, and invasive procedures may be needed to obtain adequate samples. Molecular methods of detection such as polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), and antibody-antigen assays have been developed in an effort to solve these problems. These techniques are very sensitive and have the potential to detect Pneumocystis life-forms in noninvasive samples such as sputum, oral washes, nasopharyngeal aspirates, and serum. This review evaluates 100 studies that compare use of various diagnostic tests for Pneumocystis jirovecii pneumonia (PCP) in patient samples. Novel diagnostic methods have been widely used in the research setting but have faced barriers to clinical implementation including: interpretation of low fungal burdens, standardization of techniques, integration into resource-poor settings, poor understanding of the impact of host factors, geographic variations in the organism, heterogeneity of studies, and limited clinician recognition of PCP. Addressing these barriers will require identification of phenotypes that progress to PCP and diagnostic cut-offs for colonization, generation of life-form specific markers, comparison of commercial PCR assays, investigation of cost-effective point of care options, evaluation of host factors such as HIV status that may impact diagnosis, and identification of markers of genetic diversity that may be useful in diagnostic panels. Performing high-quality studies and educating physicians will be crucial to improve the rates of diagnosis of PCP and ultimately to improve patient outcomes.
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Affiliation(s)
- Marjorie Bateman
- Center for Translational Research in Infection and Inflammation, Tulane University School of Medicine, New Orleans, LA 70122, USA
| | - Rita Oladele
- Department of Medical Microbiology and Parasitology, College of Medicine, University of Lagos, Nigeria
| | - Jay K Kolls
- Center for Translational Research in Infection and Inflammation, Tulane University School of Medicine, New Orleans, LA 70122, USA
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2
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Hosseini-Moghaddam SM, Dufresne PJ, Hunter Gutierrez E, Dufresne SF, House AA, Humar A, Kumar D, Jevnikar AM. Long-lasting cluster of nosocomial pneumonia with a single Pneumocystis jirovecii genotype involving different organ allograft recipients. Clin Transplant 2020; 34:e14108. [PMID: 33048378 DOI: 10.1111/ctr.14108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/03/2020] [Accepted: 10/05/2020] [Indexed: 02/04/2023]
Abstract
Pneumocystis pneumonia (PCP) outbreaks may occur in solid organ transplant (SOT) patients. Transmissibility of Pneumocystis jirovecii among SOT and non-SOT patients has not been investigated. Ten SOT (ie, 4 heart, 4 kidney, 2 liver allograft recipients) and 11 non-SOT (ie, 7 HIV-infected, 3 hematologic malignancies, and 1 stem cell transplant) patients with PCP were admitted to London Health Sciences Center (LHSC) from October 2014 to August 2016. We investigated the course of illness and outcome of PCP in SOT and non-SOT patients. Post-transplant PCP was frequently an acute-onset disease (90% vs. 18.2%, p = .01) requiring ICU admission (70% vs. 20%, p = .03) and hemodialysis (60% vs. 0, p = .003). Mortality was more frequent in SOT patients (40% vs. 18.1%, p = .36). Multilocus sequence typing (MLST) demonstrated circulation of a single genotype of P. jirovecii among SOT patients. However, 8 different genotypes were detected from non-SOT patients. Reinstitution of prophylaxis successfully controlled post-transplant cluster until end of observation period in October 2019. No transmission was detected from non-SOT patients to SOT recipients. Detection of a single P. jirovecii genotype from all SOT recipients highlights the likelihood of nosocomial transmission. No source control method is recommended by current guidelines. Improvement of preventive strategies is required.
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Affiliation(s)
- Seyed M Hosseini-Moghaddam
- Transplant Infectious Diseases Program, Division of Infectious Diseases, Department of Medicine, University Health Network, University of Toronto, Toronto, ON, Canada.,Department of Epidemiology and Biostatistics, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada.,Multiorgan Transplant Program, London Health Sciences Center, Western University, London, ON, Canada
| | - Philippe J Dufresne
- Laboratoire de Santé Publique du Québec, Institut National de Santé Publique du Québec, Ste-Anne-de-Bellevue, QC, Canada
| | - Elaine Hunter Gutierrez
- Multiorgan Transplant Program, London Health Sciences Center, Western University, London, ON, Canada
| | - Simon F Dufresne
- Laboratoire de Santé Publique du Québec, Institut National de Santé Publique du Québec, Ste-Anne-de-Bellevue, QC, Canada
| | - Andrew A House
- Multiorgan Transplant Program, London Health Sciences Center, Western University, London, ON, Canada
| | - Atul Humar
- Transplant Infectious Diseases Program, Division of Infectious Diseases, Department of Medicine, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Deepali Kumar
- Transplant Infectious Diseases Program, Division of Infectious Diseases, Department of Medicine, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Anthony M Jevnikar
- Multiorgan Transplant Program, London Health Sciences Center, Western University, London, ON, Canada
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Ma L, Cissé OH, Kovacs JA. A Molecular Window into the Biology and Epidemiology of Pneumocystis spp. Clin Microbiol Rev 2018; 31:e00009-18. [PMID: 29899010 PMCID: PMC6056843 DOI: 10.1128/cmr.00009-18] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Pneumocystis, a unique atypical fungus with an elusive lifestyle, has had an important medical history. It came to prominence as an opportunistic pathogen that not only can cause life-threatening pneumonia in patients with HIV infection and other immunodeficiencies but also can colonize the lungs of healthy individuals from a very early age. The genus Pneumocystis includes a group of closely related but heterogeneous organisms that have a worldwide distribution, have been detected in multiple mammalian species, are highly host species specific, inhabit the lungs almost exclusively, and have never convincingly been cultured in vitro, making Pneumocystis a fascinating but difficult-to-study organism. Improved molecular biologic methodologies have opened a new window into the biology and epidemiology of Pneumocystis. Advances include an improved taxonomic classification, identification of an extremely reduced genome and concomitant inability to metabolize and grow independent of the host lungs, insights into its transmission mode, recognition of its widespread colonization in both immunocompetent and immunodeficient hosts, and utilization of strain variation to study drug resistance, epidemiology, and outbreaks of infection among transplant patients. This review summarizes these advances and also identifies some major questions and challenges that need to be addressed to better understand Pneumocystis biology and its relevance to clinical care.
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Affiliation(s)
- Liang Ma
- Critical Care Medicine Department, NIH Clinical Center, Bethesda, Maryland, USA
| | - Ousmane H Cissé
- Critical Care Medicine Department, NIH Clinical Center, Bethesda, Maryland, USA
| | - Joseph A Kovacs
- Critical Care Medicine Department, NIH Clinical Center, Bethesda, Maryland, USA
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4
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Blount RJ, Daly KR, Fong S, Chang E, Grieco K, Greene M, Stone S, Balmes J, Miller RF, Walzer PD, Huang L. Effects of clinical and environmental factors on bronchoalveolar antibody responses to Pneumocystis jirovecii: A prospective cohort study of HIV+ patients. PLoS One 2017; 12:e0180212. [PMID: 28692651 PMCID: PMC5503245 DOI: 10.1371/journal.pone.0180212] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 06/12/2017] [Indexed: 11/26/2022] Open
Abstract
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 Pneumocystis pneumonia (PCP). We used local air quality monitoring data to assign ozone, nitrogen dioxide, and fine particulate matter exposures within 14 days prior to hospital admission. We quantified serum and bronchoalveolar lavage fluid (BALF) antibody responses to P. jirovecii major surface glycoprotein (Msg) recombinant constructs using ELISA. We then fit linear regression models to determine whether PCP and ambient air pollutants were associated with bronchoalveolar antibody responses to Msg. RESULTS Of 81 HIV-infected patients enrolled, 47 (58%) were diagnosed with current PCP and 9 (11%) had a prior history of PCP. The median CD4+ count was 51 cells/μl (IQR 15-129) and 44% were current smokers. Serum antibody responses to Msg were statistically significantly predictive of BALF antibody responses, with the exception of IgG responses to MsgC8 and MsgC9. Prior PCP was associated with increased BALF IgA responses to Msg and current PCP was associated with decreased IgA responses. For instance, among patients without current PCP, those with prior PCP had a median 73.2 U (IQR 19.2-169) IgA response to MsgC1 compared to a 5.00 U (3.52-12.6) response among those without prior PCP. Additionally, current PCP predicted a 22.5 U (95%CI -39.2, -5.82) lower IgA response to MsgC1. Ambient ozone within the two weeks prior to hospital admission was associated with decreased BALF IgA responses to Msg while nitrogen dioxide was associated with increased IgA responses. CONCLUSIONS PCP and ambient air pollutants were associated with BALF IgA responses to P. jirovecii in HIV-infected patients evaluated for suspected PCP.
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Affiliation(s)
- Robert J. Blount
- Division of Pulmonary and Critical Care Medicine, University of California, San Francisco, California, United States of America
- Division of Pediatric Pulmonology, University of California, San Francisco, California, United States of America
| | - Kieran R. Daly
- Division of Infectious Diseases, University of Cincinnati, Cincinnati, Ohio, United States of America
- Veterans Administration Medical Center, Cincinnati, Ohio, United States of America
| | - Serena Fong
- HIV/AIDS Division, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Emily Chang
- HIV/AIDS Division, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Katherine Grieco
- HIV/AIDS Division, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Meredith Greene
- HIV/AIDS Division, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Stephen Stone
- HIV/AIDS Division, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - John Balmes
- Division of Pulmonary and Critical Care Medicine, University of California, San Francisco, California, United States of America
- Environmental Health Sciences, University of California, Berkeley, California, United States of America
| | - Robert F. Miller
- Research Department of Infection and Population Health, Institute of Epidemiology and Healthcare, University College London, London, United Kingdom
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Peter D. Walzer
- Division of Infectious Diseases, University of Cincinnati, Cincinnati, Ohio, United States of America
- Veterans Administration Medical Center, Cincinnati, Ohio, United States of America
| | - Laurence Huang
- Division of Pulmonary and Critical Care Medicine, University of California, San Francisco, California, United States of America
- HIV/AIDS Division, San Francisco General Hospital, University of California, San Francisco, California, United States of America
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5
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Tomás AL, Cardoso F, Esteves F, Matos O. Serological diagnosis of pneumocystosis: production of a synthetic recombinant antigen for immunodetection of Pneumocystis jirovecii. Sci Rep 2016; 6:36287. [PMID: 27824115 PMCID: PMC5099754 DOI: 10.1038/srep36287] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 10/13/2016] [Indexed: 11/30/2022] Open
Abstract
Diagnosis of Pneumocystis pneumonia (PcP) relies on the detection of P. jirovecii in respiratory specimens obtained by invasive techniques. Thus, the development of a serological test is urgently needed as it will allow the diagnosis of PcP using blood, an inexpensive and non-invasive specimen. This study aims to combine the production of a multi-epitope synthetic recombinant antigen (RSA) and an ELISA test for detection of anti-P. jirovecii antibodies, in order to develop a new approach for PcP diagnosis. The RSA was selected and designed based on the study of the immunogenicity of the carboxyl-terminal domain of the major surface glycoprotein. This antigen was purified and used as an antigenic tool in an ELISA technique for detection of Ig, IgG and IgM antibodies anti-P. jirovecii (patent-pending no. PT109078). Serum specimens from 88 patients previously categorized in distinct clinical subgroups and 17 blood donors, were analysed. The IgM anti-P. jirovecii levels were statistically increased in patients with PcP (p = 0.001) and the ELISA IgM anti-P. jirovecii test presented a sensitivity of 100% and a specificity of 80.8%, when associated with the clinical diagnosis criteria. This innovative approach, provides good insights about what can be done in the future serum testing for PcP diagnosis.
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Affiliation(s)
- A. L. Tomás
- Unidade de Parasitologia Médica, Grupo de Protozoários Oportunistas/VIH e Outros Protozoários, Instituto de Higiene e Medicina Tropical, Global Health and Tropical Medicine, Universidade Nova de Lisboa, Lisboa, Portugal
| | - F. Cardoso
- Unidade de Parasitologia Médica, Grupo de Protozoários Oportunistas/VIH e Outros Protozoários, Instituto de Higiene e Medicina Tropical, Global Health and Tropical Medicine, Universidade Nova de Lisboa, Lisboa, Portugal
| | - F. Esteves
- Centro de Toxicogenómica e Saúde Humana (ToxOmics), Departamento de Genética, NOVA Medical School/Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal
| | - O. Matos
- Unidade de Parasitologia Médica, Grupo de Protozoários Oportunistas/VIH e Outros Protozoários, Instituto de Higiene e Medicina Tropical, Global Health and Tropical Medicine, Universidade Nova de Lisboa, Lisboa, Portugal
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Urabe N, Ishii Y, Hyodo Y, Aoki K, Yoshizawa S, Saga T, Murayama SY, Sakai K, Homma S, Tateda K. Molecular epidemiologic analysis of a Pneumocystis pneumonia outbreak among renal transplant patients. Clin Microbiol Infect 2015; 22:365-371. [PMID: 26724988 DOI: 10.1016/j.cmi.2015.12.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 12/11/2015] [Accepted: 12/14/2015] [Indexed: 10/22/2022]
Abstract
Between 18 November and 3 December 2011, five renal transplant patients at the Department of Nephrology, Toho University Omori Medical Centre, Tokyo, were diagnosed with Pneumocystis pneumonia (PCP). We used molecular epidemiologic methods to determine whether the patients were infected with the same strain of Pneumocystis jirovecii. DNA extracted from the residual bronchoalveolar lavage fluid from the five outbreak cases and from another 20 cases of PCP between 2007 and 2014 were used for multilocus sequence typing to compare the genetic similarity of the P. jirovecii. DNA base sequencing by the Sanger method showed some regions where two bases overlapped and could not be defined. A next-generation sequencer was used to analyse the types and ratios of these overlapping bases. DNA base sequences of P. jirovecii in the bronchoalveolar lavage fluid from four of the five PCP patients in the 2011 outbreak and from another two renal transplant patients who developed PCP in 2013 were highly homologous. The Sanger method revealed 14 genomic regions where two differing DNA bases overlapped and could not be identified. Analyses of the overlapping bases by a next-generation sequencer revealed that the differing types of base were present in almost identical ratios. There is a strong possibility that the PCP outbreak at the Toho University Omori Medical Centre was caused by the same strain of P. jirovecii. Two different types of base present in some regions may be due to P. jirovecii's being a diploid species.
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Affiliation(s)
- N Urabe
- Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Japan
| | - Y Ishii
- Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Japan.
| | - Y Hyodo
- Department of Nephrology Medicine, Japan
| | - K Aoki
- Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Japan
| | - S Yoshizawa
- Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Japan
| | - T Saga
- Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Japan
| | - S Y Murayama
- Laboratory of Molecular Cell Biology, School of Pharmacy, Nihon University, Funabashi, Chiba, Japan
| | - K Sakai
- Department of Nephrology Medicine, Japan
| | - S Homma
- Department of Respiratory Medicine, Toho University Omori Medical Centre, Otaku, Tokyo, Japan
| | - K Tateda
- Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Japan
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Abstract
The interaction between host immunity and infections in the context of a suppressed immune system presents an opportunity to study the interaction of colonization and infection with the development of acute and chronic pulmonary morbidity and mortality. This article summarizes presentations at the Pittsburgh International Lung Conference about comorbid consequences in two categories of immunosuppressed hosts: HIV-infected individuals and lung transplant recipients. Specifically, chronic obstructive pulmonary disease, pulmonary hypertension, and chronic lung rejection after transplant are three diseases that may be consequences of colonization or infection by viruses or fungi, whether HIV itself or the opportunistic infections Pneumocystis and cytomegalovirus. In the fourth section, we discuss unique aspects of infections after lung transplant as well as the battle against multidrug-resistant organisms in this population and theorize that the immunosuppressed population may provide a unique group of patients in which to study ways to overcome nosocomial pathogenic challenges. These host-pathogen interactions serve as models for developing new strategies to reduce acute and chronic morbidity due to colonization and subclinical infection, and potential therapeutic avenues, which are often overlooked in the clinical arena.
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8
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Khodavaisy S, Mortaz E, Mohammadi F, Aliyali M, Fakhim H, Badali H. Pneumocystis jirovecii colonization in Chronic Obstructive Pulmonary Disease (COPD). Curr Med Mycol 2015; 1:42-48. [PMID: 28680980 PMCID: PMC5490321 DOI: 10.18869/acadpub.cmm.1.1.42] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is associated with a chronic inflammatory response in airways and lung parenchyma that results in significant morbidity and mortality worldwide. Cigarette smoking considered as an important risk factor plays a role in pathogenesis of disease. Pneumocystis jirovecii is an atypical opportunistic fungus that causes pneumonia in immunosuppressed host, although the low levels of its DNA in patients without signs and symptoms of pneumonia, which likely represents colonization. The increased prevalence of P. jirovecii colonization in COPD patients has led to an interest in understanding its role in the disease. P. jirovecii colonization in these patients could represent a problem for public health since colonized patients could act as a major reservoir and source of infection for susceptible subjects. Using sensitive molecular techniques, low levels of P. jirovecii DNA have been detected in the respiratory tract of certain individuals. It is necessary to elucidate the role of P. jirovecii colonization in the natural history of COPD patients in order to improve the clinical management of this disease. In the current review paper, we discuss P. jirovecii colonization in COPD patients.
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Affiliation(s)
- S Khodavaisy
- Department of Medical Parasitology and Mycology, Kurdistan University of Medical Sciences, Sanandaj, Iran.,Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - E Mortaz
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - F Mohammadi
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - M Aliyali
- Pulmonary and Critical Care Division, Mazandaran University of Medical Sciences, Sari, Iran
| | - H Fakhim
- Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - H Badali
- Department of Medical Mycology and Parasitology/Invasive Fungi Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
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10
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Fong S, Daly KR, Tipirneni R, Jarlsberg LG, Djawe K, Koch JV, Swartzman A, Roth B, Walzer PD, Huang L. Antibody responses against Pneumocystis jirovecii in health care workers over time. Emerg Infect Dis 2014; 19:1612-9. [PMID: 24048016 PMCID: PMC3810734 DOI: 10.3201/eid1910.121836] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
In a previous cross-sectional study, we showed that clinical staff working in a hospital had significantly higher antibody levels than nonclinical staff to Pneumocystis jirovecii. We conducted a longitudinal study, described here, to determine whether occupation and self-reported exposure to a patient with P. jirovecii pneumonia were associated with antibody levels to P. jirovecii over time. Baseline and quarterly serum specimens were collected and analyzed by using an ELISA that targeted different variants of the Pneumocystis major surface glycoprotein (MsgA, MsgB, MsgC1, MsgC3, MsgC8, and MsgC9). Clinical staff had significantly higher estimated geometric mean antibody levels against MsgC1 and MsgC8 than did nonclinical staff over time. Significant differences were observed when we compared the change in antibody levels to the different MsgC variants for staff who were and were not exposed to P. jirovecii pneumonia-infected patients. MsgC variants may serve as indicators of exposure to P. jirovecii in immunocompetent persons.
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Outbreak of pneumocystis pneumonia in renal and liver transplant patients caused by genotypically distinct strains of Pneumocystis jirovecii. Transplantation 2013; 96:834-42. [PMID: 23903011 DOI: 10.1097/tp.0b013e3182a1618c] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND An outbreak of 29 cases of Pneumocystis jirovecii pneumonia (PCP) occurred among renal and liver transplant recipients (RTR and LTR) in the largest Danish transplantation centre between 2007 and 2010, when routine PCP prophylaxis was not used. METHODS P. jirovecii isolates from 22 transplant cases, 2 colonized RTRs, and 19 Pneumocystis control samples were genotyped by restriction fragment length polymorphism and multilocus sequence typing analysis. Contact tracing was used to investigate transmission. Potential risk factors were compared between PCP cases and matched non-PCP transplant patients. RESULTS Three unique Pneumocystis genotypes were shared among 19 of the RTRs, LTRs, and a colonized RTR in three distinct clusters, two of which overlapped temporally. In contrast, Pneumocystis control samples harbored a wide range of genotypes. Evidence of possible nosocomial transmission was observed. Among several potential risk factors, only cytomegalovirus viremia was consistently associated with PCP (P=0.03; P=0.009). Mycophenolate mofetil was associated with PCP risk only in the RTR population (P=0.04). CONCLUSION We identified three large groups infected with unique strains of Pneumocystis and provide evidence of an outbreak profile and nosocomial transmission. LTRs may be infected in PCP outbreaks simultaneously with RTRs and by the same strains, most likely by interhuman transmission. Patients are at risk several years after transplantation, but the risk is highest during the first 6 months after transplantation. Because patients at risk cannot be identified clinically and outbreaks cannot be predicted, 6 months of PCP chemoprophylaxis should be considered for all RTRs and LTRs.
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12
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Djawe K, Daly KR, Levin L, Zar HJ, Walzer PD. Humoral immune responses to Pneumocystis jirovecii antigens in HIV-infected and uninfected young children with pneumocystis pneumonia. PLoS One 2013; 8:e82783. [PMID: 24386119 PMCID: PMC3873266 DOI: 10.1371/journal.pone.0082783] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 10/28/2013] [Indexed: 02/02/2023] Open
Abstract
Background Humoral immune responses in human immunodeficiency virus (HIV)-infected and uninfected children with Pneumocystis pneumonia (PcP) are poorly understood. Methods Consecutive children hospitalized with acute pneumonia, tachypnea, and hypoxia in South Africa were investigated for PcP, which was diagnosed by real-time polymerase chain reaction on lower respiratory tract specimens. Serum antibody responses to recombinant fragments of the carboxyl terminus of Pneumocystis jirovecii major surface glycoprotein (MsgC) were analyzed. Results 149 children were enrolled of whom 96 (64%) were HIV-infected. PcP occurred in 69 (72%) of HIV-infected and 14 (26%) of HIV-uninfected children. HIV-infected children with PcP had significantly decreased IgG antibodies to MsgC compared to HIV-infected patients without PcP, but had similar IgM antibodies. In contrast, HIV-uninfected children with PcP showed no change in IgG antibodies to MsgC, but had significantly increased IgM antibodies compared to HIV-uninfected children without PCP. Age was an independent predictor of high IgG antibodies, whereas PcP was a predictor of low IgG antibodies and high IgM antibodies. IgG and IgM antibody levels to the most closely related MsgC fragments were predictors of survival from PcP. Conclusions Young HIV-infected children with PcP have significantly impaired humoral immune responses to MsgC, whereas HIV-uninfected children with PcP can develop active humoral immune responses. The children also exhibit a complex relationship between specific host factors and antibody levels to MsgC fragments that may be related to survival from PcP.
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Affiliation(s)
- Kpandja Djawe
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Kieran R. Daly
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Research Service, Veterans Affairs Medical Center, Cincinnati, Ohio, United States of America
| | - Linda Levin
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Heather J. Zar
- Department of Pediatrics and Child Health, University of Cape Town, Cape Town, South Africa
| | - Peter D. Walzer
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Research Service, Veterans Affairs Medical Center, Cincinnati, Ohio, United States of America
- * E-mail:
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13
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Walzer PD. The ecology of pneumocystis: perspectives, personal recollections, and future research opportunities. J Eukaryot Microbiol 2013; 60:634-45. [PMID: 24001365 DOI: 10.1111/jeu.12072] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 07/17/2013] [Accepted: 07/17/2013] [Indexed: 11/28/2022]
Abstract
I am honored to receive the second Lifetime Achievement Award by International Workshops on Opportunistic Protists and to give this lecture. My research involves Pneumocystis, an opportunistic pulmonary fungus that is a major cause of pneumonia ("PcP") in the immunocompromised host. I decided to focus on Pneumocystis ecology here because it has not attracted much interest. Pneumocystis infection is acquired by inhalation, and the cyst stage appears to be the infective form. Several fungal lung infections, such as coccidiomycosis, are not communicable, but occur by inhaling < 5 μm spores from environmental sources (buildings, parks), and can be affected by environmental factors. PcP risk factors include environmental constituents (temperature, humidity, SO2 , CO) and outdoor activities (camping). Clusters of PcP have occurred, but no environmental source has been found. Pneumocystis is communicable and outbreaks of PcP, especially in renal transplant patients, are an ongoing problem. Recent evidence suggests that most viable Pneumocystis organisms detected in the air are confined to a patient's room. Further efforts are needed to define the risk of Pneumocystis transmission in health care facilities; to develop more robust preventive measures; and to characterize the effects of climatological and air pollutant factors on Pneumocystis transmission in animal models similar to those used for respiratory viruses.
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Affiliation(s)
- Peter D Walzer
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, 45267-0560; Research Service, Veterans Affairs Medical Center, Cincinnati, Ohio, 45220
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Menotti J, Emmanuel A, Bouchekouk C, Chabe M, Choukri F, Pottier M, Sarfati C, Aliouat EM, Derouin F. Evidence of airborne excretion of Pneumocystis carinii during infection in immunocompetent rats. Lung involvement and antibody response. PLoS One 2013; 8:e62155. [PMID: 23626781 PMCID: PMC3633925 DOI: 10.1371/journal.pone.0062155] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/18/2013] [Indexed: 01/15/2023] Open
Abstract
To better understand the role of immunocompetent hosts in the diffusion of Pneumocystis in the environment, airborne shedding of Pneumocystis carinii in the surrounding air of experimentally infected Sprague Dawley rats was quantified by means of a real-time PCR assay, in parallel with the kinetics of P. carinii loads in lungs and specific serum antibody titres. Pneumocystis-free Sprague Dawley rats were intratracheally inoculated at day 0 (d0) and then followed for 60 days. P. carinii DNA was detected in lungs until d29 in two separate experiments and thereafter remained undetectable. A transient air excretion of Pneumocystis DNA was observed between d14 and d22 in the first experiment and between d9 and d19 in the second experiment; it was related to the peak of infection in lungs. IgM and IgG anti-P. carinii antibody increase preceded clearance of P. carinii in the lungs and cessation of airborne excretion. In rats receiving a second challenge 3 months after the first inoculation, Pneumocystis was only detected at a low level in the lungs of 2 of 3 rats at d2 post challenge and was never detected in air samples. Anti-Pneumocystis antibody determinations showed a typical secondary IgG antibody response. This study provides the first direct evidence that immunocompetent hosts can excrete Pneumocystis following a primary acquired infection. Lung infection was apparently controlled by the immune response since fungal burdens decreased to become undetectable as specific antibodies reached high titres in serum. This immune response was apparently protective against reinfection 3 months later.
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Affiliation(s)
- Jean Menotti
- Department of Parasitology-Mycology, E.A.3520, Paris-Diderot University, Sorbonne Paris Cité and Saint-Louis Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France.
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Blount RJ, Jarlsberg LG, Daly KR, Worodria W, Davis JL, Cattamanchi A, Djawe K, Andama A, Koch J, Walzer PD, Huang L. Serologic responses to recombinant Pneumocystis jirovecii major surface glycoprotein among Ugandan patients with respiratory symptoms. PLoS One 2012; 7:e51545. [PMID: 23284710 PMCID: PMC3528778 DOI: 10.1371/journal.pone.0051545] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Accepted: 11/02/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Little is known about the serologic responses to Pneumocystis jirovecii major surface glycoprotein (Msg) antigen in African cohorts, or the IgM responses to Msg in HIV-positive and HIV-negative persons with respiratory symptoms. METHODS We conducted a prospective study of 550 patients, both HIV-positive (n = 467) and HIV-negative (n = 83), hospitalized with cough ≥2 weeks in Kampala, Uganda, to evaluate the association between HIV status, CD4 cell count, and other clinical predictors and antibody responses to P. jirovecii. We utilized ELISA to measure the IgM and IgG serologic responses to three overlapping recombinant fragments that span the P. jirovecii major surface glycoprotein: MsgA (amino terminus), MsgB (middle portion) and MsgC1 (carboxyl terminus), and to three variations of MsgC1 (MsgC3, MsgC8 and MsgC9). RESULTS HIV-positive patients demonstrated significantly lower IgM antibody responses to MsgC1, MsgC3, MsgC8 and MsgC9 compared to HIV-negative patients. We found the same pattern of low IgM antibody responses to MsgC1, MsgC3, MsgC8 and MsgC9 among HIV-positive patients with a CD4 cell count <200 cells/µl compared to those with a CD4 cell count ≥200 cells/µl. HIV-positive patients on PCP prophylaxis had significantly lower IgM responses to MsgC3 and MsgC9, and lower IgG responses to MsgA, MsgC1, MsgC3, and MsgC8. In contrast, cigarette smoking was associated with increased IgM antibody responses to MsgC1 and MsgC3 but was not associated with IgG responses. We evaluated IgM and IgG as predictors of mortality. Lower IgM responses to MsgC3 and MsgC8 were both associated with increased in-hospital mortality. CONCLUSIONS HIV infection and degree of immunosuppression are associated with reduced IgM responses to Msg. In addition, low IgM responses to MsgC3 and MsgC8 are associated with increased mortality.
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Affiliation(s)
- Robert J Blount
- Division of Pulmonary and Critical Care Medicine, San Francisco General Hospital, University of California San Francisco, San Francisco, CA, USA.
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Abstract
Although the incidence of Pneumocystis pneumonia (PCP) has decreased since the introduction of combination antiretroviral therapy, it remains an important cause of disease in both HIV-infected and non-HIV-infected immunosuppressed populations. The epidemiology of PCP has shifted over the course of the HIV epidemic both from changes in HIV and PCP treatment and prevention and from changes in critical care medicine. Although less common in non-HIV-infected immunosuppressed patients, PCP is now more frequently seen due to the increasing numbers of organ transplants and development of novel immunotherapies. New diagnostic and treatment modalities are under investigation. The immune response is critical in preventing this disease but also results in lung damage, and future work may offer potential areas for vaccine development or immunomodulatory therapy. Colonization with Pneumocystis is an area of increasing clinical and research interest and may be important in development of lung diseases such as chronic obstructive pulmonary disease. In this review, we discuss current clinical and research topics in the study of Pneumocystis and highlight areas for future research.
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Djawe K, Daly KR, Vargas SL, Santolaya ME, Ponce CA, Bustamante R, Koch J, Levin L, Walzer PD. Seroepidemiological study of Pneumocystis jirovecii infection in healthy infants in Chile using recombinant fragments of the P. jirovecii major surface glycoprotein. Int J Infect Dis 2011; 14:e1060-6. [PMID: 20926326 DOI: 10.1016/j.ijid.2010.07.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 06/25/2010] [Accepted: 07/03/2010] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVES To characterize the seroepidemiological features of Pneumocystis jirovecii infection in healthy Chilean children using overlapping fragments (A, B, C) of the P. jirovecii major surface glycoprotein (Msg). METHODS Serum antibodies to MsgA, MsgB, and MsgC were measured every 2 months by enzyme-linked immunosorbent assay (ELISA) in 45 Chilean infants from about age 2 months to 2 years. RESULTS Peak antibody levels (usually reached at age 6 months) and the force (or rate) of infection were somewhat greater for MsgC than for MsgA. Significant seasonal variation in antibody levels was only found with MsgA. Respiratory infections occurred in most children, but nasopharyngeal aspirates were of limited value in detecting the organism. In contrast, serological responses commonly occurred, and higher levels only to MsgC were significantly related to the number of infections. CONCLUSIONS Serological responses to recombinant Msg fragments provide new insights into the epidemiological and clinical features of P. jirovecii infection of early childhood. MsgA, the amino terminus fragment, is more sensitive in detecting seasonal influences on antibody levels, whereas MsgC is better able to detect changes in antibody levels in response to clinical infection.
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Affiliation(s)
- Kpandja Djawe
- Department of Environmental Health, University of Cincinnati, Cincinnati, Ohio, USA
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Djawe K, Huang L, Daly KR, Levin L, Koch J, Schwartzman A, Fong S, Roth B, Subramanian A, Grieco K, Jarlsberg L, Walzer PD. Serum antibody levels to the Pneumocystis jirovecii major surface glycoprotein in the diagnosis of P. jirovecii pneumonia in HIV+ patients. PLoS One 2010; 5:e14259. [PMID: 21151564 PMCID: PMC3000336 DOI: 10.1371/journal.pone.0014259] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 11/10/2010] [Indexed: 12/27/2022] Open
Abstract
Background Pneumocystis jirovecii remains an important cause of fatal pneumonia (Pneumocystis pneumonia or PcP) in HIV+ patients and other immunocompromised hosts. Despite many previous attempts, a clinically useful serologic test for P. jirovecii infection has never been developed. Methods/Principal Findings We analyzed serum antibody responses to the P. jirovecii major surface glycoprotein recombinant fragment C1 (MsgC1) in 110 HIV+ patients with active PcP (cases) and 63 HIV+ patients with pneumonia due to other causes (controls) by an enzyme-linked immunosorbent assay (ELISA). The cases had significantly higher IgG and IgM antibody levels to MsgC1 than the controls at hospital admission (week 0) and intervals up to at least 1 month thereafter. The sensitivity, specificity and positive predictive value (PPV) of IgG antibody levels increased from 57.2%, 61.7% and 71.5% at week 0 to 63.4%, 100%, and 100%, respectively, at weeks 3–4. The sensitivity, specificity and PPV of IgM antibody levels rose from 59.7%, 61.3%, and 79.3% at week 0 to 74.6%, 73.7%, and 89.8%, respectively, at weeks 3–4. Multivariate analysis revealed that a diagnosis of PcP was the only independent predictor of high IgG and IgM antibody levels to MsgC1. A high LDH level, a nonspecific marker of lung damage, was an independent predictor of low IgG antibody levels to MsgC1. Conclusions/Significance The results suggest that the ELISA shows promise as an aid to the diagnosis of PCP in situations where diagnostic procedures cannot be performed. Further studies in other patient populations are needed to better define the usefulness of this serologic test.
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Affiliation(s)
- Kpandja Djawe
- Veterans Affairs Medical Center, Cincinnati, Ohio, United States of America
- Division of Epidemiology and Biostatistics, Department of Environmental Health, University College of Medicine, Cincinnati, Ohio, United States of America
| | - Laurence Huang
- Division of Pulmonary and Critical Care Medicine and HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Kieran R. Daly
- Veterans Affairs Medical Center, Cincinnati, Ohio, United States of America
- Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Linda Levin
- Division of Epidemiology and Biostatistics, Department of Environmental Health, University College of Medicine, Cincinnati, Ohio, United States of America
| | - Judy Koch
- Veterans Affairs Medical Center, Cincinnati, Ohio, United States of America
- Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Alexandra Schwartzman
- Division of Pulmonary and Critical Care Medicine and HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Serena Fong
- Division of Pulmonary and Critical Care Medicine and HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Brenna Roth
- Division of Pulmonary and Critical Care Medicine and HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Anuradha Subramanian
- Division of Pulmonary and Critical Care Medicine and HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Katherine Grieco
- Division of Pulmonary and Critical Care Medicine and HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Leah Jarlsberg
- Division of Pulmonary and Critical Care Medicine and HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America
| | - Peter D. Walzer
- Veterans Affairs Medical Center, Cincinnati, Ohio, United States of America
- Division of Epidemiology and Biostatistics, Department of Environmental Health, University College of Medicine, Cincinnati, Ohio, United States of America
- Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail:
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