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Belanger CR, Locher K, Velapatino B, Dufresne PJ, Eckbo E, Charles M. Quick versus Quantitative: Evaluation of Two Commercial Real-Time PCR Assays for the Detection of Pneumocystis jirovecii from Bronchoalveolar Lavage Fluids. Microbiol Spectr 2023; 11:e0102123. [PMID: 37260378 PMCID: PMC10434167 DOI: 10.1128/spectrum.01021-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 05/12/2023] [Indexed: 06/02/2023] Open
Abstract
Two commercial real-time PCR assays for the detection of Pneumocystis jirovecii were compared, the quantitative RealStar P. jirovecii assay and the qualitative DiaSorin P. jirovecii assay, the latter of which can be used without nucleic acid extraction. Archived bronchoalveolar lavage (BAL) specimens (n = 66), previously tested by molecular methods, were tested by both assays, and the results were compared to the respective original result. The RealStar P. jirovecii assay demonstrated good positive percent agreement (PPA) (90% [95% confidence interval (CI), 72 to 97%]; 27/30) and negative percent agreement (NPA) (100% [95% CI, 88 to 100%]; 36/36) with the reference method. The DiaSorin P. jirovecii assay concordantly detected P. jirovecii in 19 of 24 positive BAL samples (PPA = 73% [95% CI, 52 to 88%]). All negative BAL samples gave concordant results (NPA = 100% [95% CI, 87 to 100%]; 34/34). Discordant results occurred mostly in samples with low fungal loads. In conclusion, the RealStar assay demonstrated good concordance with reference results, and the DiaSorin P. jirovecii assay performed well for negative BAL and positive BAL samples with P. jirovecii concentrations of greater than 260 copies/mL. IMPORTANCE Pneumonia, caused by the opportunistic fungus Pneumocystis jirovecii, poses a significant risk for immunocompromised individuals. Laboratory testing for P. jirovecii is progressively shifting toward the use of molecular tests such as real-time PCR; however, this is often performed at reference laboratories. Many frontline laboratories are looking into improving their service and reducing turnaround times for obtaining P. jirovecii results by bringing molecular P. jirovecii testing in-house. We evaluated and compared two commercial real-time PCR assays with different workflows for the detection of P. jirovecii from bronchoalveolar lavage specimens. The RealStar P. jirovecii assay requires nucleic acid extraction and provides a quantification of fungal load for positive samples. The DiaSorin P. jirovecii assay offers a simple workflow without nucleic extraction from patient samples and qualitative results. Results from this study provide valuable information on performance and workflow considerations for laboratories that wish to implement P. jirovecii molecular testing.
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Affiliation(s)
- Corrie R. Belanger
- Division of Medical Microbiology, Vancouver Coastal Health, Vancouver, British Columbia, Canada
| | - Kerstin Locher
- Division of Medical Microbiology, Vancouver Coastal Health, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Billie Velapatino
- Division of Medical Microbiology, Vancouver Coastal Health, Vancouver, British Columbia, Canada
| | - Philippe J. Dufresne
- Laboratoire de santé publique du Québec, Institut national de santé publique du Québec, Sainte-Anne-de-Bellevue, Québec, Canada
| | - Eric Eckbo
- Division of Medical Microbiology, Vancouver Coastal Health, Vancouver, British Columbia, Canada
| | - Marthe Charles
- Division of Medical Microbiology, Vancouver Coastal Health, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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2
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Rabacal W, Schweitzer F, Kling HM, Buzzelli L, Rayens E, Norris KA. A therapeutic vaccine strategy to prevent Pneumocystis pneumonia in an immunocompromised host in a non-human primate model of HIV and Pneumocystis co-infection. Front Immunol 2022; 13:1036658. [PMID: 36561749 PMCID: PMC9763597 DOI: 10.3389/fimmu.2022.1036658] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 11/10/2022] [Indexed: 12/12/2022] Open
Abstract
Introduction Pneumocystis is a ubiquitous fungal pathogen that causes pneumonia (PCP) and pulmonary sequelae in HIV-infected individuals and other immunocompromised populations. With the success of anti-retroviral therapy for HIV-infected individuals the frequency of PCP in that population has decreased, however, PCP remains a significant cause of morbidity and mortality in individuals with hematologic and solid malignancies, and in individuals treated with immunosuppressive therapies for autoimmune diseases, and following bone marrow and solid organ transplantation. Despite the clinical need, there is no approved vaccine to prevent PCP in vulnerable populations. The ultimate goal of the field is to develop an effective vaccine that can overcome immune deficits in at risk populations and induce long-lasting protective immunity to Pneumocystis. Toward this goal, our laboratory has established a model of PCP co-infection in simian immunodeficiency virus (SIV)-infected non-human primates (NHP) and identified a recombinant protein sub-unit vaccine, KEX1, that induces robust anti-Pneumocystis immunity in immune-competent macaques that is durable and prevents PCP following simian immunodeficiency virus (SIV)-induced immunosuppression. Type I, or invariant natural killer T (iNKT) cells have the potential to provide B cell help under conditions of reduced CD4+ T cell help. Methods In the present study, we used the SIV model of HIV infection to address whether therapeutic vaccination with the iNKT cell-activating adjuvant α-galactosylceramide (α-GC) and KEX1 (α-GC+KEX1) can effectively boost anti-Pneumocystis humoral immunity following virus-induced immunosuppression. Results Immunization of antigen-experienced NHPs with α-GC+KEX1 during the early chronic phase of SIV-infection significantly boosted anti-Pneumocystis humoral immunity by increasing memory B cells and antibody titers, and enhanced titer durability during SIV-induced immunosuppression. This therapeutic vaccination strategy boosted anti-Pneumocystis immune responses during SIV-infection and contributed to protection against Pneumocystis co-infection in KEX1-vaccinated macaques. Conclusion These studies present a novel strategy for stimulating durable anti-Pneumocystis humoral immunity in the context of complex, chronic SIV-induced immunosuppression and may be further applied to immunization of other immunosuppressed populations, and toward other common recall antigens.
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Affiliation(s)
- Whitney Rabacal
- Center for Vaccines and Immunology, Department of Infectious Diseases, University of Georgia, Athens, GA, United States,*Correspondence: Whitney Rabacal,
| | - Finja Schweitzer
- Center for Vaccines and Immunology, Department of Infectious Diseases, University of Georgia, Athens, GA, United States
| | - Heather M. Kling
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Lizabeth Buzzelli
- Center for Vaccines and Immunology, Department of Infectious Diseases, University of Georgia, Athens, GA, United States
| | - Emily Rayens
- Center for Vaccines and Immunology, Department of Infectious Diseases, University of Georgia, Athens, GA, United States
| | - Karen A. Norris
- Center for Vaccines and Immunology, Department of Infectious Diseases, University of Georgia, Athens, GA, United States
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Concurrent Infection with SARS-CoV-2 and Pneumocystis jirovecii in Immunocompromised and Immunocompetent Individuals. J Fungi (Basel) 2022; 8:jof8060585. [PMID: 35736068 PMCID: PMC9225243 DOI: 10.3390/jof8060585] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 05/24/2022] [Accepted: 05/24/2022] [Indexed: 12/15/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) may occur with concurrent infections caused by bacterial and fungal microorganisms. This systematic review evaluated studies reporting concomitant COVID-19 and Pneumocystis jirovecii pneumonia (PJP). We found 39 patients (74% male, median age: 56.8 (range: 11–83) years), including 66% immunosuppressed individuals (23% HIV-infected and 41% on long-term corticosteroid therapy). Patients were characteristically severely ill (mechanical ventilation: 70%), associated with 41% mortality. The median lymphocyte count was 527 cells/mm3 (range: 110–2200), and the median CD4+ T cell count was 206 cells/mm3 (range: 8–1021). We identified three patterns of concurrent COVID-19 and P. jirovecii infection. The first pattern (airway colonization with a low burden of P. jirovecii) does not seem to modify the COVID-19 course of illness. However, P. jirovecii superinfection, typically occurring weeks after COVID-19 diagnosis as a biphasic illness, and P. jirovecii coinfection characteristically results in progressive multilobar pneumonia, which is associated with poor outcomes. To support this categorization, we reported three patients with concurrent PJP and COVID-19 identified in our institution, presenting these clinical scenarios. The diagnosis of PJP requires a high index of suspicion, since clinical and radiological characteristics overlap with COVID-19. Observational studies are necessary to determine the PJP burden in patients with COVID-19 requiring hospitalization.
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Fonte L, Ginori M, Calderón EJ, de Armas Y. Prevalence of Pneumocystosis in Sub-Saharan Africa and Helminth Immune Modulation. J Fungi (Basel) 2021; 8:jof8010045. [PMID: 35049985 PMCID: PMC8779910 DOI: 10.3390/jof8010045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 11/30/2022] Open
Abstract
Sub-Saharan Africa is the region of the world with the highest prevalence of helminth infections. To protect themselves from the defensive mechanisms of their respective hosts, helminths modulate their immune responses. This modulation has relevant clinical and epidemiological consequences, including the inhibition of inflammatory processes that characterize infection by other microorganisms. Severe Pneumocystis pneumonia is characterized by an intense inflammatory reaction that can lead to death. Acquired immunodeficiency syndrome is the main predisposing factor to the development of pneumocystosis. Although the introduction of highly active antiretroviral therapy has led to a notable decline in the incidence of acquired immunodeficiency syndrome-associated complications, pneumocystosis continues to be an important global health problem. Despite the high incidence of human immunodeficiency virus infection in the sub-Saharan region, the prevalence of Pneumocystis pneumonia there has been lower than expected. Several factors, or combinations thereof, may contribute to this evolution. Here, we hypothesize the possible role of helminth immune modulation as an important issue at play. On the other hand, and looking ahead, we believe that the immune modulation achieved by helminths may be an important factor to consider during the design and evaluation processes of vaccines against Pneumocystis jirovecii to be used in Sub-Saharan Africa. The requirements of a balanced triggering of different types of immune responses for controlling the infection produced by this microorganism, as observed during experiments in animal models, support this final consideration.
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Affiliation(s)
- Luis Fonte
- Parasitology Department, Institute of Tropical Medicine “Pedro Kourí”, Havana 11400, Cuba
- Correspondence: (L.F.); (E.J.C.); Tel.: +34-955923096 (E.J.C.)
| | - María Ginori
- Department of Teaching, Polyclinic “Plaza de la Revolución”, Havana 11300, Cuba;
| | - Enrique J. Calderón
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investiga-Ciones Científicas/Universidad de Sevilla, 41013 Seville, Spain
- Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
- Correspondence: (L.F.); (E.J.C.); Tel.: +34-955923096 (E.J.C.)
| | - Yaxsier de Armas
- Department of Clinical Microbiology Diagnostic, Hospital Center of Institute of Tropical Medicine “Pedro Kourí”, Havana 11400, Cuba;
- Pathology Department, Hospital Center of Institute of Tropical Medicine “Pedro Kourí”, Havana 11400, Cuba
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5
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Kim D, Kim SB, Jeon S, Kim S, Lee KH, Lee HS, Han SH. No Change of Pneumocystis jirovecii Pneumonia after the COVID-19 Pandemic: Multicenter Time-Series Analyses. J Fungi (Basel) 2021; 7:jof7110990. [PMID: 34829277 PMCID: PMC8624436 DOI: 10.3390/jof7110990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/08/2021] [Accepted: 11/17/2021] [Indexed: 11/30/2022] Open
Abstract
Consolidated infection control measures imposed by the government and hospitals during COVID-19 pandemic resulted in a sharp decline of respiratory viruses. Based on the issue of whether Pneumocystis jirovecii could be transmitted by airborne and acquired from the environment, we assessed changes in P. jirovecii pneumonia (PCP) cases in a hospital setting before and after COVID-19. We retrospectively collected data of PCP-confirmed inpatients aged ≥18 years (N = 2922) in four university-affiliated hospitals between January 2015 and June 2021. The index and intervention dates were defined as the first time of P. jirovecii diagnosis and January 2020, respectively. We predicted PCP cases for post-COVID-19 and obtained the difference (residuals) between forecasted and observed cases using the autoregressive integrated moving average (ARIMA) and the Bayesian structural time-series (BSTS) models. Overall, the average of observed PCP cases per month in each year were 36.1 and 47.3 for pre- and post-COVID-19, respectively. The estimate for residuals in the ARIMA model was not significantly different in the total PCP-confirmed inpatients (7.4%, p = 0.765). The forecasted PCP cases by the BSTS model were not significantly different from the observed cases in the post-COVID-19 (−0.6%, 95% credible interval; −9.6~9.1%, p = 0.450). The unprecedented strict non-pharmacological interventions did not affect PCP cases.
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Affiliation(s)
- Dayeong Kim
- Department of Internal Medicine, Division of Infectious Disease, Yonsei University College of Medicine, 211 Eonju-ro, Gangnam-gu, Seoul 06273, Korea; (D.K.); (S.K.); (K.H.L.)
| | - Sun Bean Kim
- Department of Internal Medicine, Division of Infectious Diseases, Korea University College of Medicine, 73, Goryeodae-ro, Seongbuk-gu, Seoul 02841, Korea;
| | - Soyoung Jeon
- Biostatistics Collaboration Unit, Yonsei University College of Medicine, 211 Eonju-ro, Gangnam-gu, Seoul 06273, Korea;
| | - Subin Kim
- Department of Internal Medicine, Division of Infectious Disease, Yonsei University College of Medicine, 211 Eonju-ro, Gangnam-gu, Seoul 06273, Korea; (D.K.); (S.K.); (K.H.L.)
| | - Kyoung Hwa Lee
- Department of Internal Medicine, Division of Infectious Disease, Yonsei University College of Medicine, 211 Eonju-ro, Gangnam-gu, Seoul 06273, Korea; (D.K.); (S.K.); (K.H.L.)
| | - Hye Sun Lee
- Biostatistics Collaboration Unit, Yonsei University College of Medicine, 211 Eonju-ro, Gangnam-gu, Seoul 06273, Korea;
- Correspondence: (H.S.L.); (S.H.H.)
| | - Sang Hoon Han
- Department of Internal Medicine, Division of Infectious Disease, Yonsei University College of Medicine, 211 Eonju-ro, Gangnam-gu, Seoul 06273, Korea; (D.K.); (S.K.); (K.H.L.)
- Correspondence: (H.S.L.); (S.H.H.)
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Vera C, Rueda ZV. Transmission and Colonization of Pneumocystis jirovecii. J Fungi (Basel) 2021; 7:jof7110979. [PMID: 34829266 PMCID: PMC8622989 DOI: 10.3390/jof7110979] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/01/2021] [Accepted: 11/05/2021] [Indexed: 11/17/2022] Open
Abstract
Pneumocystis spp. was discovered in 1909 and was classified as a fungus in 1988. The species that infects humans is called P. jirovecii and important characteristics of its genome have recently been discovered. Important advances have been made to understand P. jirovecii, including aspects of its biology, evolution, lifecycle, and pathogenesis; it is now considered that the main route of transmission is airborne and that the infectious form is the asci (cyst), but it is unclear whether there is transmission by direct contact or droplet spread. On the other hand, P. jirovecii has been detected in respiratory secretions of hosts without causing disease, which has been termed asymptomatic carrier status or colonization (frequency in immunocompetent patients: 0–65%, pregnancy: 15.5%, children: 0–100%, HIV-positive patients: 20–69%, cystic fibrosis: 1–22%, and COPD: 16–55%). This article briefly describes the history of its discovery and the nomenclature of Pneumocystis spp., recently uncovered characteristics of its genome, and what research has been done on the transmission and colonization of P. jirovecii. Based on the literature, the authors of this review propose a hypothetical natural history of P. jirovecii infection in humans.
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Affiliation(s)
- Cristian Vera
- Grupo de Investigación en Salud Pública, Research Department, Facultad de Medicina, Universidad Pontificia Bolivariana, Medellín 050031, Colombia
- Correspondence:
| | - Zulma Vanessa Rueda
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg RT3, Colombia;
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7
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Charpentier E, Ménard S, Marques C, Berry A, Iriart X. Immune Response in Pneumocystis Infections According to the Host Immune System Status. J Fungi (Basel) 2021; 7:jof7080625. [PMID: 34436164 PMCID: PMC8399367 DOI: 10.3390/jof7080625] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 12/12/2022] Open
Abstract
The host immune response is critical in Pneumocystis pneumonia (PCP). Immunocompetent hosts can eliminate the fungus without symptoms, while immunodeficient hosts develop PCP with an unsuitable excessive inflammatory response leading to lung damage. From studies based on rodent models or clinical studies, this review aimed to better understand the pathophysiology of Pneumocystis infection by analysing the role of immune cells, mostly lymphocytes, according to the immune status of the infected host. Hence, this review first describes the immune physiological response in infected immunocompetent hosts that are able to eliminate the fungus. The objective of the second part is to identify the immune elements required for the control of the fungus, focusing on specific immune deficiencies. Finally, the third part concentrates on the effect of the different immune elements in immunocompromised subjects during PCP, to better understand which cells are detrimental, and which, on the contrary, are beneficial once the disease has started. This work highlights that the immune response associated with a favourable outcome of the infection may differ according to the immune status of the host. In the case of immunocompetency, a close communication between B cells and TCD4 within tertiary lymphocyte structures appears critical to activate M2 macrophages without much inflammation. Conversely, in the case of immunodeficiency, a pro-inflammatory response including Th1 CD4, cytotoxic CD8, NK cells, and IFNγ release seems beneficial for M1 macrophage activation, despite the impact of inflammation on lung tissue.
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Affiliation(s)
- Eléna Charpentier
- Department of Parasitology-Mycology, Toulouse University Hospital, 31059 Toulouse, France;
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
- Correspondence: (E.C.); (X.I.)
| | - Sandie Ménard
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
| | - Catherine Marques
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
| | - Antoine Berry
- Department of Parasitology-Mycology, Toulouse University Hospital, 31059 Toulouse, France;
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
| | - Xavier Iriart
- Department of Parasitology-Mycology, Toulouse University Hospital, 31059 Toulouse, France;
- Infinity, Inserm, CNRS, University of Toulouse III, 31024 Toulouse, France; (S.M.); (C.M.)
- Correspondence: (E.C.); (X.I.)
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8
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Gingerich AD, Norris KA, Mousa JJ. Pneumocystis Pneumonia: Immunity, Vaccines, and Treatments. Pathogens 2021; 10:pathogens10020236. [PMID: 33669726 PMCID: PMC7921922 DOI: 10.3390/pathogens10020236] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/11/2021] [Accepted: 02/16/2021] [Indexed: 12/18/2022] Open
Abstract
For individuals who are immunocompromised, the opportunistic fungal pathogen Pneumocystis jirovecii is capable of causing life-threatening pneumonia as the causative agent of Pneumocystis pneumonia (PCP). PCP remains an acquired immunodeficiency disease (AIDS)-defining illness in the era of antiretroviral therapy. In addition, a rise in non-human immunodeficiency virus (HIV)-associated PCP has been observed due to increased usage of immunosuppressive and immunomodulating therapies. With the persistence of HIV-related PCP cases and associated morbidity and mortality, as well as difficult to diagnose non-HIV-related PCP cases, an improvement over current treatment and prevention standards is warranted. Current therapeutic strategies have primarily focused on the administration of trimethoprim-sulfamethoxazole, which is effective at disease prevention. However, current treatments are inadequate for treatment of PCP and prevention of PCP-related death, as evidenced by consistently high mortality rates for those hospitalized with PCP. There are no vaccines in clinical trials for the prevention of PCP, and significant obstacles exist that have slowed development, including host range specificity, and the inability to culture Pneumocystis spp. in vitro. In this review, we overview the immune response to Pneumocystis spp., and discuss current progress on novel vaccines and therapies currently in the preclinical and clinical pipeline.
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Affiliation(s)
- Aaron D. Gingerich
- Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (A.D.G.); (K.A.N.)
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Karen A. Norris
- Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (A.D.G.); (K.A.N.)
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Jarrod J. Mousa
- Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (A.D.G.); (K.A.N.)
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
- Correspondence:
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9
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The Domestic Environment and the Lung Mycobiome. Microorganisms 2020; 8:microorganisms8111717. [PMID: 33147738 PMCID: PMC7693370 DOI: 10.3390/microorganisms8111717] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/16/2020] [Accepted: 10/30/2020] [Indexed: 12/16/2022] Open
Abstract
This study analyzes the relationship between the mycobiome of the Lower Respiratory Tract (LRT) and the fungi in the domestic environment. Samples studied consisted of Broncho-Alveolar Lavage (BAL) from 45 patients who underwent bronchoscopy for different diagnostic purposes, and dust and air from the houses (ENV) of 20 of them (44.4%). Additionally, five bronchoscopes (BS) were also analyzed and negative controls were included for every procedure. All samples were processed for DNA extraction and cultures, which were performed in Sabouraud Dextrose and Potato Dextrose Agar. The fungal Internal Transcribed Spacer (ITS2) was sequenced by the Solexa/Illumina system and sequences were analyzed by QIIME 1.8.0 and compared with the UNITE Database for identification. The similarity between the two fungal communities (BAL and ENV) for a specific patient was assessed via the percentage of coincidence in the detection of specific operational taxonomic units (OTUs), and about 75% of co-occurrence was detected between the mycobiome of the LRT and the houses. Cultures confirmed the presence of the core mycobiome species. However, the low rate of isolation from BAL suggests that most of its mycobiome corresponds to non-culturable cells. This likely depends on the patient’s immune system activity and inflammatory status.
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10
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Fata A, Abdollahi B, Rezaeetalab F, Attaran D, Najjari M, Najafzadeh MJ. Molecular diagnosis and genotyping of Pneumocystis jirovecii in bronchoalveolar lavage samples obtained from patients with pulmonary disorder. Curr Med Mycol 2019; 5:13-18. [PMID: 31850391 PMCID: PMC6910711 DOI: 10.18502/cmm.5.3.1741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background and Purpose: Pneumocystis pneumonia (PCP) is one of the most common and life-threatening fungal diseases in patients with human immunodeficiency, treated with immunosuppressive medications. Immunocompetent people can also be a spreading agent for PCP. Regarding this, the aim of the present study was to diagnose and identify Pneumocystis jirovecii in bronchoalveolar lavage (BAL) samples obtained from patients with pulmonary disorder using a molecular method. Materials and Methods: For the purpose of the study, BAL samples (n=138) were collected from patients, undergoing bronchoscopy at the different departments of university hospitals affiliated to Mashhad University of Medical Sciences, Mashhad, Iran, during a period of one year (i.e., April 2014 until May 2015). Giemsa staining and molecular identification were carried out for each sample. The samples were also subjected to nested polymerase chain reaction (PCR), sequencing, and genotyping based on mitochondrial ribosomal large subunit (mtLSU rRNA) of P. jirovecii. The phylogenic tree was constructed by MEGA6 software. Results: The results of direct microscopic examination revealed the presence of P. jirovecii in 3 (2.2%) out of 138 samples; in addition, nested PCR and sequencing led to the detection of species in 17 (12.3%) samples. Out of patients with positive results, 10 (25%) and 7 (7.1%) cases were immunosuppressed and immunocompetent, respectively. The most common clinical symptoms among patients with pneumocystis were fever, dyspnea, and dry cough. In addition, genotypes III and II were the dominant genotypes in our dataset. Conclusion: Nested PCR and sequencing methods showed higher sensitivity and specificity as compared with a direct staining technique. Genotype III was identified as the most dominant type in patients with pulmonary disorder in Mashhad.
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Affiliation(s)
- Abdolmajid Fata
- Department of Parasitology and Mycology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Cutaneous Leishmaniasis Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Bahareh Abdollahi
- Department of Parasitology and Mycology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Fariba Rezaeetalab
- Department of Internal Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Lung Diseases Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Davood Attaran
- Department of Internal Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Lung Diseases Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohsen Najjari
- Department of Parasitology and Mycology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad J Najafzadeh
- Department of Parasitology and Mycology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Cancer Molecular Pathology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
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11
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Colonization by Pneumocystis jirovecii in patients with chronic obstructive pulmonary disease: association with exacerbations and lung function status. Braz J Infect Dis 2019; 23:352-357. [PMID: 31545952 PMCID: PMC9427795 DOI: 10.1016/j.bjid.2019.08.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 08/16/2019] [Accepted: 08/23/2019] [Indexed: 11/21/2022] Open
Abstract
Exposure to Pneumocystis jirovecii (P. jirovecii) can lead to a wide variety of presenting features ranging from colonization in immunocompetent patients with lung disease, to invasive infections in immunocompromised hosts. Colonization by this fungus in patients with chronic obstructive pulmonary disease (COPD) could be associated with higher rates of exacerbations and impaired lung function in these patients. Our objective was to determine whether colonization by P. jirovecii in patients with COPD is associated with increased exacerbations and deterioration of lung function. This was a prospective cohort study on patients with COPD. All participants meeting selection criteria underwent clinical and microbiological assessments and were then classified as colonized vs. non-colonized patients. Chi-squared tests were performed and multivariate logistic models were fitted in order to obtain risk ratios (RR) with 95% confidence intervals (CI). We documented a frequency of colonization by P. jirovecii of 32.3%. Most patients were categorized as having GOLD B and D COPD. The history of significant exacerbations in the last year, health status impairment (COPD Assesment Tool ≥10), airflow limitation (percent of post-bronchodilator FEV1), and BODEx score (≥5) were similar between groups. After a 52-week follow-up period, the rate of adjusted significant exacerbations did not differ between groups. However, a decrease in FEVI was found in both groups.
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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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Rojas P, Friaza V, García E, de la Horra C, Vargas SL, Calderón EJ, Pavón A. Early Acquisition of Pneumocystis jirovecii Colonization and Potential Association With Respiratory Distress Syndrome in Preterm Newborn Infants. Clin Infect Dis 2018; 65:976-981. [PMID: 28520902 DOI: 10.1093/cid/cix454] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 05/11/2017] [Indexed: 12/16/2022] Open
Abstract
Background Pneumocystis pneumonia is a well-recognized lung disease of premature and malnourished babies. Even though serologic studies have shown that children are exposed to Pneumocystis jirovecii early in life, the epidemiology of human P. jirovecii infection and the host-microorganism relationship in infancy remain poorly understood. The aim of the present study was to investigate the prevalence of P. jirovecii colonization in preterm infants and its possible association with medical complications. Methods A prospective observational study of preterm infants (birth weight <1500 g and/or gestational age <32 weeks) was carried out. Identification of P. jirovecii colonization was performed by means of molecular techniques in nasal aspirated samples at birth. Results A total of 128 preterm infants were included during the study period. Pneumocystis DNA was identified in 25.7% (95% confidence interval [CI], 17.8%-33.7%) of newborns studied. A significant increase of respiratory distress syndrome in colonized group, even after adjusting for confounding factors (odds ratio, 2.7 [95% CI, 1.0-7.5]; P = .04), was observed. No differences were observed in other medical conditions between the 2 groups. Conclusions Pneumocystis jirovecii colonization is frequent in preterm births and could be a risk factor to develop respiratory distress syndrome among preterm infants.
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Affiliation(s)
- Pilar Rojas
- Neonatology Unit, Virgen del Rocío University Children's Hospital
| | - Vicente Friaza
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, and Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública, Hospital Universitario Virgen del Rocío, Seville, Spain
| | - Elisa García
- Neonatology Unit, Virgen del Rocío University Children's Hospital
| | - Carmen de la Horra
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, and Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública, Hospital Universitario Virgen del Rocío, Seville, Spain
| | - Sergio L Vargas
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago
| | - Enrique J Calderón
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, and Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública, Hospital Universitario Virgen del Rocío, Seville, Spain
| | - Antonio Pavón
- Neonatology Unit, Virgen del Rocío University Children's Hospital
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Kehrmann J, Veckollari B, Schmidt D, Schildgen O, Schildgen V, Wagner N, Zeschnigk M, Klein-Hitpass L, Witzke O, Buer J, Steinmann J. The lung microbiome in patients with pneumocystosis. BMC Pulm Med 2017; 17:170. [PMID: 29202739 PMCID: PMC5715545 DOI: 10.1186/s12890-017-0512-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 11/20/2017] [Indexed: 12/31/2022] Open
Abstract
Backround Pneumocystis jirovecii pneumonia (PCP) is an opportunistic fungal infection that is associated with a high morbidity and mortality in immunocompromised individuals. In this study, we analysed the microbiome of the lower respiratory tract from critically ill intensive care unit patients with and without pneumocystosis. Methods Broncho-alveolar fluids from 65 intubated and mechanically ventilated intensive care unit patients (34 PCP+ and 31 PCP- patients) were collected. Sequence analysis of bacterial 16S rRNA gene V3/V4 regions was performed to study the composition of the respiratory microbiome using the Illumina MiSeq platform. Results Differences in the microbial composition detected between PCP+ and PCP- patients were not statistically significant on class, order, family and genus level. In addition, alpha and beta diversity metrics did not reveal significant differences between PCP+ and PCP- patients. The composition of the lung microbiota was highly variable between PCP+ patients and comparable in its variety with the microbiota composition of the heterogeneous collective of PCP- patients. Conclusions The lower respiratory tract microbiome in patients with pneumocystosis does not appear to be determined by a specific microbial composition or to be dominated by a single bacterial species. Electronic supplementary material The online version of this article (10.1186/s12890-017-0512-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- J Kehrmann
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany.
| | - B Veckollari
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany
| | - D Schmidt
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany
| | - O Schildgen
- Institute of Pathology, Kliniken der Stadt Köln gGmbH, Hospital of the University of Witten/Herdecke, Cologne, Germany
| | - V Schildgen
- Institute of Pathology, Kliniken der Stadt Köln gGmbH, Hospital of the University of Witten/Herdecke, Cologne, Germany
| | - N Wagner
- Institute of Human Genetics, Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
| | - M Zeschnigk
- Institute of Human Genetics, Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
| | - L Klein-Hitpass
- Biochip Laboratory, Institute for Cell Biology-Tumor Research, University of Duisburg-Essen, Essen, Germany
| | - O Witzke
- Department of Infectious Diseases, University of Duisburg-Essen, Essen, Germany
| | - J Buer
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany
| | - J Steinmann
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany. .,Present Address: Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Klinikum Nürnberg, Paracelsus Medical University, Prof.-Ernst-Nathan-Str. 1, 90419, Nürnberg, Germany.
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Eddens T, Elsegeiny W, Garcia-Hernadez MDLL, Castillo P, Trevejo-Nunez G, Serody K, Campfield BT, Khader SA, Chen K, Rangel-Moreno J, Kolls JK. Pneumocystis-Driven Inducible Bronchus-Associated Lymphoid Tissue Formation Requires Th2 and Th17 Immunity. Cell Rep 2017; 18:3078-3090. [PMID: 28355561 DOI: 10.1016/j.celrep.2017.03.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 02/02/2017] [Accepted: 03/02/2017] [Indexed: 12/26/2022] Open
Abstract
Inducible bronchus-associated lymphoid tissue (iBALT) is an ectopic lymphoid structure composed of highly organized T cell and B cell zones that forms in the lung in response to infectious or inflammatory stimuli. Here, we develop a model for fungal-mediated iBALT formation, using infection with Pneumocystis that induces development of pulmonary lymphoid follicles. Pneumocystis-dependent iBALT structure formation and organization required CXCL13 signaling. Cxcl13 expression was regulated by interleukin (IL)-17 family members, as Il17ra-/-, Il17rb-/-, and Il17rc-/- mice failed to develop iBALT. Interestingly, Il17rb-/- mice have intact Th17 responses, but failed to generate an anti-Pneumocystis Th2 response. Given a role for Th2 and Th17 immunity in iBALT formation, we demonstrated that primary pulmonary fibroblasts synergistically upregulated Cxcl13 transcription following dual stimulation with IL-13 and IL-17A in a STAT3/GATA3-dependent manner. Together, these findings uncover a role for Th2/Th17 cells in regulating Cxcl13 expression and provide an experimental model for fungal-driven iBALT formation.
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Affiliation(s)
- Taylor Eddens
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA
| | - Waleed Elsegeiny
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA
| | | | - Patricia Castillo
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA
| | - Giraldina Trevejo-Nunez
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA
| | - Katelin Serody
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA
| | - Brian T Campfield
- Division of Pediatric Infectious Diseases, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Shabaana A Khader
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kong Chen
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA
| | - Javier Rangel-Moreno
- Department of Medicine, Allergy/Immunology, and Rheumatology, University of Rochester, Rochester, NY 14624, USA
| | - Jay K Kolls
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA.
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Wang RJ, Miller RF, Huang L. Approach to Fungal Infections in Human Immunodeficiency Virus-Infected Individuals: Pneumocystis and Beyond. Clin Chest Med 2017; 38:465-477. [PMID: 28797489 DOI: 10.1016/j.ccm.2017.04.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Many fungi cause pulmonary disease in patients with human immunodeficiency virus (HIV) infection. Pathogens include Pneumocystis jirovecii, Cryptococcus neoformans, Aspergillus spp, Histoplasma capsulatum, Coccidioides spp, Blastomyces dermatitidis, Paracoccidioides brasiliensis, Talaromyces marneffei, and Emmonsia spp. Because symptoms are frequently nonspecific, a high index of suspicion for fungal infection is required for diagnosis. Clinical manifestations of fungal infection in HIV-infected patients frequently depend on the degree of immunosuppression and the CD4+ helper T cell count. Establishing definitive diagnosis is important because treatments differ. Primary and secondary prophylaxes depend on CD4+ helper T cell counts, geographic location, and local prevalence of disease.
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Affiliation(s)
- Richard J Wang
- Department of Medicine, University of California, San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143, USA
| | - Robert F Miller
- Research Department of Infection and Population Health, Institute of Global Health, University College London, Gower Street, London WC1E 6BT, UK; Faculty of Infectious and Tropical Diseases, Department of Clinical Research, London School of Hygiene and Tropical Medicine, Keppel Street, Bloomsbury, London WC1E 7HT, UK
| | - Laurence Huang
- Department of Medicine, University of California, San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143, USA.
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White PL, Backx M, Barnes RA. Diagnosis and management of Pneumocystis jirovecii infection. Expert Rev Anti Infect Ther 2017; 15:435-447. [PMID: 28287010 DOI: 10.1080/14787210.2017.1305887] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Pneumocystis jirovecii is a ubiquitous fungus, which causes pneumonia in humans. Diagnosis was hampered by the inability to culture the organism, and based on microscopic examination of respiratory samples or clinical presentation. New assays can assist in the diagnosis and even aid with the emergence of resistant infections. Areas covered: This manuscript will provide background information on Pneumocystis pneumonia (PcP). Diagnosis, from radiological to non-microbiological (e.g. Lactate dehydrogenase) and microbiological investigations (Microscopy, PCR, β-D-Glucan) will be discussed. Recommendations on prophylactic and therapeutic management will be covered. Expert commentary: PcP diagnosis using microscopy is far from optimal and false negatives will occur. With an incidence of 1% or less, the pre-test probability of not having PcP is 99% and testing is suited to excluding disease. Microscopy provides a high degree of diagnostic confidence but it is not infallible, and its lower sensitivity limits its application. Newer diagnostics (PCR, β-D-Glucan) can aid management and improve performance when testing less invasive specimens, such as upper respiratory samples or blood, alleviating clinical pressure. Combination testing may allow PcP to be both diagnosed and excluded, and molecular testing can assist in the detection of emerging resistant PcP.
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Affiliation(s)
- P Lewis White
- a Public Health Wales Microbiology Cardiff, UHW , Cardiff , UK
| | - Matthijs Backx
- a Public Health Wales Microbiology Cardiff, UHW , Cardiff , UK
| | - Rosemary A Barnes
- a Public Health Wales Microbiology Cardiff, UHW , Cardiff , UK.,b Infection, Immunity and Biochemistry , Cardiff University, School of Medicine, UHW , Cardiff , UK
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Eddens T, Campfield BT, Serody K, Manni ML, Horne W, Elsegeiny W, McHugh KJ, Pociask D, Chen K, Zheng M, Alcorn JF, Wenzel S, Kolls JK. A Novel CD4 + T Cell-Dependent Murine Model of Pneumocystis-driven Asthma-like Pathology. Am J Respir Crit Care Med 2016; 194:807-820. [PMID: 27007260 DOI: 10.1164/rccm.201511-2205oc] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Infection with Pneumocystis, an opportunistic fungal pathogen, can result in fulminant pneumonia in the clinical setting of patients with immunosuppression. In murine models, Pneumocystis has previously been shown to induce a CD4+ T cell-dependent eosinophilic response in the lung capable of providing protection. OBJECTIVES We sought to explore the role of Pneumocystis in generating asthma-like lung pathology, given the natural eosinophilic response to infection. METHODS Pneumocystis infection or antigen treatment was used to induce asthma-like pathology in wild-type mice. The roles of CD4+ T cells and eosinophils were examined using antibody depletion and knockout mice, respectively. The presence of anti-Pneumocystis antibodies in human serum samples was detected by ELISA and Western blotting. MEASUREMENTS AND MAIN RESULTS Pneumocystis infection generates a strong type II response in the lung that requires CD4+ T cells. Pneumocystis infection was capable of priming a Th2 response similar to that of a commonly studied airway allergen, the house dust mite. Pneumocystis antigen treatment was also capable of inducing allergic inflammation in the lung, resulting in anti-Pneumocystis IgE production, goblet cell hyperplasia, and increased airway resistance. In the human population, patients with severe asthma had increased levels of anti-Pneumocystis IgG and IgE compared with healthy control subjects. Patients with severe asthma with elevated anti-Pneumocystis IgG levels had worsened symptom scores and lung parameters such as decreased forced expiratory volume and increased residual volume compared with patients with severe asthma who had low anti-Pneumocystis IgG. CONCLUSIONS The present study demonstrates for the first time, to our knowledge, that Pneumocystis is an airway allergen capable of inducing asthma-like lung pathology.
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Affiliation(s)
- Taylor Eddens
- 1 Richard King Mellon Foundation Institute for Pediatric Research and.,2 Department of Immunology
| | - Brian T Campfield
- 1 Richard King Mellon Foundation Institute for Pediatric Research and.,3 Division of Pediatric Infectious Diseases, Department of Pediatrics, and
| | - Katelin Serody
- 1 Richard King Mellon Foundation Institute for Pediatric Research and
| | - Michelle L Manni
- 4 Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - William Horne
- 1 Richard King Mellon Foundation Institute for Pediatric Research and
| | - Waleed Elsegeiny
- 1 Richard King Mellon Foundation Institute for Pediatric Research and.,2 Department of Immunology
| | - Kevin J McHugh
- 4 Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - Derek Pociask
- 5 Department of Pulmonary Diseases, Critical Care, and Environmental Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Kong Chen
- 1 Richard King Mellon Foundation Institute for Pediatric Research and
| | - Mingquan Zheng
- 1 Richard King Mellon Foundation Institute for Pediatric Research and
| | - John F Alcorn
- 4 Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - Sally Wenzel
- 6 Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; and
| | - Jay K Kolls
- 1 Richard King Mellon Foundation Institute for Pediatric Research and
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Kling HM, Norris KA. Vaccine-Induced Immunogenicity and Protection Against Pneumocystis Pneumonia in a Nonhuman Primate Model of HIV and Pneumocystis Coinfection. J Infect Dis 2016; 213:1586-95. [PMID: 26823337 PMCID: PMC4837913 DOI: 10.1093/infdis/jiw032] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 01/20/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The ubiquitous opportunistic pathogen Pneumocystis jirovecii causes pneumonia in immunocompromised individuals, including human immunodeficiency virus (HIV)-infected individuals, and pulmonary colonization with P. jirovecii is believed to be a cofactor in the development of chronic obstructive pulmonary disease. There is no vaccine for P. jirovecii; however, most adults are seropositive, indicating natural immune priming to this pathogen. We have shown that humoral response to a recombinant subunit of the P. jirovecii protease kexin (KEX1) correlates with protection from P. jirovecii colonization and pneumonia. METHODS Here we evaluated the immunogenicity and protective capacity of the recombinant KEX1 peptide vaccine in a preclinical, nonhuman primate model of HIV-induced immunosuppression and Pneumocystis coinfection. RESULTS Immunization with KEX1 induced a robust humoral response remained at protective levels despite chronic simian immunodeficiency virus/HIV-induced immunosuppression. KEX1-immunized macaques were protected from Pneumocystis pneumonia, compared with mock-immunized animals (P= .047), following immunosuppression and subsequent natural, airborne exposure to Pneumocystis CONCLUSIONS These data support the concept that stimulation of preexisting immunological memory to Pneumocystis with a recombinant KEX1 vaccine prior to immunosuppression induces durable memory responses and protection in the context of chronic, complex immunosuppression.
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Affiliation(s)
- Heather M Kling
- Department of Immunology, University of Pittsburgh, Pennsylvania
| | - Karen A Norris
- Department of Immunology, University of Pittsburgh, Pennsylvania
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Grubbs JA, Baddley JW. Pneumocystis jirovecii pneumonia in patients receiving tumor-necrosis-factor-inhibitor therapy: implications for chemoprophylaxis. Curr Rheumatol Rep 2015; 16:445. [PMID: 25182673 DOI: 10.1007/s11926-014-0445-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Pneumocystis jirovecii pneumonia (PJP) is an important opportunistic infection that has been increasingly reported in patients with rheumatic disease. Reported incidence among patients taking TNF inhibitors (TNFi) has varied, but has usually been low. Still, disease causes significant mortality among those affected and must be considered in patients with rheumatological disease presenting with dyspnea and cough. Diagnosis can be difficult in the non-HIV population, and our understanding of the epidemiology and natural history after exposure is changing. Trimethoprim-sulfamethoxazole is believed to be the most effective agent for treatment and prophylaxis, but is associated with significant adverse effects. Given the low incidence reported in most studies of patients on TNFi, prophylaxis is probably not beneficial for this patient population as a whole.
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Affiliation(s)
- James A Grubbs
- Department of Medicine, Division of Infectious Diseases, University of Alabama at Birmingham, 1900 University Boulevard, 229 Tinsley Harrison Tower, Birmingham, AL, 35294-0006, USA
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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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Pneumocystis Pneumonia: Epidemiology and Options for Prophylaxis in Non-HIV Immunocompromised Pediatric Patients. CURRENT FUNGAL INFECTION REPORTS 2014. [DOI: 10.1007/s12281-014-0177-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Pneumocystis jirovecii pneumonia in tropical and low and middle income countries: a systematic review and meta-regression. PLoS One 2013; 8:e69969. [PMID: 23936365 PMCID: PMC3732248 DOI: 10.1371/journal.pone.0069969] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Accepted: 06/12/2013] [Indexed: 11/19/2022] Open
Abstract
Objective Pneumocystis jirovecii pneumonia (PCP), the commonest opportunistic infection in HIV-infected patients in the developed world, is less commonly described in tropical and low and middle income countries (LMIC). We sought to investigate predictors of PCP in these settings. Design Systematic review and meta-regression. Methods Meta-regression of predictors of PCP diagnosis (33 studies). Qualitative and quantitative assessment of recorded CD4 counts, receipt of prophylaxis and antiretrovirals, sensitivity and specificity of clinical signs and symptoms for PCP, co-infection with other pathogens, and case fatality (117 studies). Results The most significant predictor of PCP was per capita Gross Domestic Product, which showed strong linear association with odds of PCP diagnosis (p<0.0001). This was not explained by study design or diagnostic quality. Geographical area, population age, study setting and year of study also contributed to risk of PCP. Co-infection was common (444 episodes/1425 PCP cases), frequently with virulent organisms. The predictive value of symptoms, signs or simple tests in LMIC settings for diagnosis of PCP was poor. Case fatality was >30%; treatment was largely appropriate. Prophylaxis appeared to reduce the risk for development of PCP, however 24% of children with PCP were receiving prophylaxis. CD4 counts at presentation with PCP were usually <200×103/ml. Conclusions There is a positive relationship between GDP and risk of PCP diagnosis. Although failure to diagnose infection in poorer countries may contribute to this, we also hypothesise that poverty exposes at-risk patients to a wide range of infections and that the relatively non-pathogenic P. jirovecii is therefore under-represented. As LMIC develop economically they eliminate the conditions underlying transmission of virulent infection: P. jirovecii, ubiquitous in all settings, then becomes a greater relative threat.
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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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Saltzman RW, Albin S, Russo P, Sullivan KE. Clinical conditions associated with PCP in children. Pediatr Pulmonol 2012; 47:510-6. [PMID: 22009851 DOI: 10.1002/ppul.21577] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Accepted: 08/16/2011] [Indexed: 01/15/2023]
Abstract
Pneumocystis jirovecii is a leading cause of opportunistic infections among the immune compromised. During the 1980s, attention focused on patients with HIV, however, with the advent of anti-retroviral therapy, we wished to revisit the question of underlying diseases associated with Pneumocystis pneumonia in children. We identified 80 cases from 1986 to 2006 and performed a retrospective chart review to identify clinical characteristics for each of the cases. HIV was the single most common associated underlying condition seen in this cohort, accounting for 39% of the cases overall, however, it was seen in just 15% of the cases since 1998. Transplant recipients and oncology patients together comprised another 39% of the cases, with 9% of cases attributed to primary immune deficiency and another 9% of cases associated with less well-recognized causes of susceptibility. This study documents the ongoing need for vigilance to diagnose Pneumocystis pneumonia in less well-recognized clinical scenarios.
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Affiliation(s)
- Rushani W Saltzman
- Division of Allergy Immunology, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
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Pneumocystis jirovecii testing by real-time polymerase chain reaction and direct examination among immunocompetent and immunosuppressed patient groups and correlation to disease specificity. Diagn Microbiol Infect Dis 2011; 69:145-52. [PMID: 21251557 DOI: 10.1016/j.diagmicrobio.2010.10.021] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 10/20/2010] [Accepted: 10/22/2010] [Indexed: 01/13/2023]
Abstract
We used real-time polymerase chain reaction (PCR) targeting the cdc2 gene and direct fluorescent microscopy examination (DFME) to evaluate the prevalence of Pneumocystis jirovecii among immunocompetent patients without clinical pulmonary infection and immunosuppressed patients evaluated for opportunistic pulmonary infections. Among 102 bronchoalveolar lavage samples collected from immunocompetent patients without infection, none tested positive for P. jirovecii by either DFME or real-time PCR despite the presence of other comorbidities. Among patients with suspected pulmonary infection and tested with either assay, real-time PCR produced a higher number of positive results compared to DFME and increased P. jirovecii detection by 7% when added to DFME-negative samples. Real-time PCR may have increased sensitivity for P. jirovecii detection over DFME and decrease the risk of sample contamination compared to conventional and nested PCR. The use of single-copy gene targets (e.g., cdc2) may lower the rate of "colonization" detection and confer a high predictive value for Pneumocystis pneumonia.
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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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Gutiérrez S, Morilla R, León JA, Martín-Garrido I, Rivero L, Friaza V, Respaldiza N, Montes-Cano MA, Terán R, de la Horra C. High prevalence of Pneumocystis jiroveci colonization among young HIV-infected patients. J Adolesc Health 2011; 48:103-5. [PMID: 21185532 DOI: 10.1016/j.jadohealth.2010.05.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 05/14/2010] [Accepted: 05/18/2010] [Indexed: 12/18/2022]
Abstract
BACKGROUND Pneumocystis colonization in young HIV-infected patients has been poorly studied. The aim of this study was to analyze the prevalence of P jiroveci colonization in a cohort of young HIV-infected patients. MATERIAL AND METHODS We designed a basal cross-sectional study in 20 young HIV-infected patients to determine the prevalence of P jiroveci colonization in oropharyngeal wash samples studied by nested polymerase chain reaction (PCR). Subsequently, patients were followed up during 50 weeks to observe the development of Pneumocystis pneumonia (PCP). RESULTS P jiroveci colonization was detected in eight (40%) of the 20 oropharyngeal wash samples. Genotype 85C/248C was the most frequent. After 50 weeks of follow-up, one colonized patient with advanced immunodepression developed PCP. CONCLUSIONS We have found a high prevalence of P jiroveci colonization in young HIV-infected patients with a major prevalence of genotype 1 (85C/248C). Further studies are necessary to clarify if Pneumocystis colonization could be a potential risk factor of developing PCP in young HIV infected patients.
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Affiliation(s)
- Sonia Gutiérrez
- Instituto de Biomedicina de Sevilla, Hospitales Universitarios Virgen del Rocío/CSIC/Universidad de Sevilla, Clinical and Molecular Epidemiology Seville, Spain.
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Camacho-Gonzalez AF, Ross AC, Chakraborty R. The clinical care of the HIV-1-infected infant. Clin Perinatol 2010; 37:873-85, xi. [PMID: 21078456 DOI: 10.1016/j.clp.2010.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Despite well-established strategies to decrease the mother-to-child transmission of HIV-1, new perinatal infections continue to occur globally, reflecting marked disparities in access to health care. Once HIV-1 infection has been established in an infant, the combination of early initiation of antiretroviral therapy and prophylaxis against Pneumocystis jiroveci pneumonia is paramount to reducing disease progression. This article reviews the recommendations and evidence for the treatment of HIV-1-infected infants.
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Affiliation(s)
- Andres F Camacho-Gonzalez
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Children's Healthcare of Atlanta, Emory University, 2015 Uppergate Drive, Suite 500, Atlanta, GA 30322, USA
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Finkelman MA. Pneumocystis jiroveciiinfection: Cell wall (1→3)-β-D-glucan biology and diagnostic utility. Crit Rev Microbiol 2010; 36:271-81. [DOI: 10.3109/1040841x.2010.484001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Catherinot E, Lanternier F, Bougnoux ME, Lecuit M, Couderc LJ, Lortholary O. Pneumocystis jirovecii Pneumonia. Infect Dis Clin North Am 2010; 24:107-38. [PMID: 20171548 DOI: 10.1016/j.idc.2009.10.010] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Pneumocystis jirovecii has gained attention during the last decade in the context of the AIDS epidemic and the increasing use of cytotoxic and immunosuppressive therapies. This article summarizes current knowledge on biology, pathophysiology, epidemiology, diagnosis, prevention, and treatment of pulmonary P jirovecii infection, with a particular focus on the evolving pathophysiology and epidemiology. Pneumocystis pneumonia still remains a severe opportunistic infection, associated with a high mortality rate.
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Affiliation(s)
- Emilie Catherinot
- Université Paris Descartes, Service de Maladies Infectieuses et Tropicales, 149 Rue de Sèvres, Centre d'Infectiologie Necker-Pasteur, Hôpital Necker-Enfants Malades, Paris 75015, France
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Tipirneni R, Daly KR, Jarlsberg LG, Koch JV, Swartzman A, Roth BM, Walzer PD, Huang L. Healthcare worker occupation and immune response to Pneumocystis jirovecii. Emerg Infect Dis 2010; 15:1590-7. [PMID: 19861050 PMCID: PMC2866396 DOI: 10.3201/eid1510.090207] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Humans may be a reservoir for this pathogen and transmit it from person to person. The reservoir and mode of transmission of Pneumocystis jirovecii remain uncertain. We conducted a cross-sectional study of 126 San Francisco General Hospital staff in clinical (n = 103) and nonclinical (n = 23) occupations to assess whether occupational exposure was associated with immune responses to P. jirovecii. We examined antibody levels by ELISA for 3 overlapping fragments that span the P. jirovecii major surface glycoprotein (Msg): MsgA, MsgB, and MsgC1. Clinical occupation participants had higher geometric mean antibody levels to MsgC1 than did nonclinical occupation participants (21.1 vs. 8.2, p = 0.004); clinical occupation was an independent predictor of higher MsgC1 antibody levels (parameter estimate = 0.89, 95% confidence interval 0.29–1.48, p = 0.003). In contrast, occupation was not significantly associated with antibody responses to either MsgA or MsgB. Healthcare workers may have occupational exposure to P. jirovecii. Humans may be a reservoir for P. jirovecii and may transmit it from person to person.
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Affiliation(s)
- Renuka Tipirneni
- HIV/AIDS Division, San Francisco General Hospital/University of California, San Francisco, California, USA.
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Complexity of the MSG gene family of Pneumocystis carinii. BMC Genomics 2009; 10:367. [PMID: 19664205 PMCID: PMC2743713 DOI: 10.1186/1471-2164-10-367] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Accepted: 08/07/2009] [Indexed: 11/17/2022] Open
Abstract
Background The relationship between the parasitic fungus Pneumocystis carinii and its host, the laboratory rat, presumably involves features that allow the fungus to circumvent attacks by the immune system. It is hypothesized that the major surface glycoprotein (MSG) gene family endows Pneumocystis with the capacity to vary its surface. This gene family is comprised of approximately 80 genes, which each are approximately 3 kb long. Expression of the MSG gene family is regulated by a cis-dependent mechanism that involves a unique telomeric site in the genome called the expression site. Only the MSG gene adjacent to the expression site is represented by messenger RNA. Several P. carinii MSG genes have been sequenced, which showed that genes in the family can encode distinct isoforms of MSG. The vast majority of family members have not been characterized at the sequence level. Results The first 300 basepairs of MSG genes were subjected to analysis herein. Analysis of 581 MSG sequence reads from P. carinii genomic DNA yielded 281 different sequences. However, many of the sequence reads differed from others at only one site, a degree of variation consistent with that expected to be caused by error. Accounting for error reduced the number of truly distinct sequences observed to 158, roughly twice the number expected if the gene family contains 80 members. The size of the gene family was verified by PCR. The excess of distinct sequences appeared to be due to allelic variation. Discounting alleles, there were 73 different MSG genes observed. The 73 genes differed by 19% on average. Variable regions were rich in nucleotide differences that changed the encoded protein. The genes shared three regions in which at least 16 consecutive basepairs were invariant. There were numerous cases where two different genes were identical within a region that was variable among family members as a whole, suggesting recombination among family members. Conclusion A set of sequences that represents most if not all of the members of the P. carinii MSG gene family was obtained. The protein-changing nature of the variation among these sequences suggests that the family has been shaped by selection for protein variation, which is consistent with the hypothesis that the MSG gene family functions to enhance phenotypic variation among the members of a population of P. carinii.
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Walzer PD, Djawe K, Levin L, Daly KR, Koch J, Kingsley L, Witt M, Golub ET, Bream JH, Taiwo B, Morris A. Long-term serologic responses to the Pneumocystis jirovecii major surface glycoprotein in HIV-positive individuals with and without P. jirovecii infection. J Infect Dis 2009; 199:1335-44. [PMID: 19301979 DOI: 10.1086/597803] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND The immune responses to Pneumocystis jirovecii major surface glycoprotein (Msg) in individuals with human immunodeficiency virus (HIV) infection are poorly understood. METHODS We examined the sequential serologic responses to recombinant Msg carboxyl terminus fragments (MsgC1, MsgC3, MsgC8, and MsgC9) by enzyme-linked immunosorbent assay in a cohort of individuals with HIV infection for the 5.5 years before death and autopsy. Analyses included mean antibody levels by status at death (Pneumocystis pneumonia, P. jirovecii colonization, or neither), factors associated with high antibody levels, and antibody responses before and after active Pneumocystis pneumonia. RESULTS Patients who died from Pneumocystis pneumonia had higher levels of antibody to MsgC8 than did patients who died from other causes. Previous episode of Pneumocystis pneumonia, geographic location, and age were independent predictors of high levels of anitbodies to most or all Msgs. Failure to take Pneumocystis pneumonia prophylaxis was associated with high levels of antibody to MsgC1. Patients who developed and recovered from active Pneumocystis pneumonia during the study exhibited an increase in serum antibody levels that persisted for months after the infection, whereas patients who developed another acquired immunodeficiency syndrome-defining illness did not. CONCLUSIONS Serum antibodies to Msgs are important markers of P. jirovecii infection in patients with HIV infection and are influenced by host and environmental factors in complex ways.
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Affiliation(s)
- Peter D Walzer
- Veterans Affairs Medical Center and Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
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Daly K, Koch J, Respaldiza N, de la Horra C, Montes-Cano MA, Medrano FJ, Varela JM, Calderon EJ, Walzer PD. Geographical variation in serological responses to recombinant Pneumocystis jirovecii major surface glycoprotein antigens. Clin Microbiol Infect 2009; 15:937-42. [PMID: 19416292 DOI: 10.1111/j.1469-0691.2009.02716.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The use of recombinant fragments of the major surface glycoprotein (Msg) of Pneumocystis jirovecii has proven useful for studying serological immune responses of blood donors and human immunodeficiency virus (HIV)-positive (HIV(+)) patients. Here, we have used ELISA to measure antibody titres to Msg fragments (MsgA, MsgB, MsgC1, MsgC3, MsgC8 and MsgC9) in sera isolated in the USA (n=200) and Spain (n=326), to determine whether geographical location affects serological responses to these antigens. Blood donors from Seville exhibited a significantly greater antibody titre to MsgC8, and significantly lower responses to MsgC3 and MsgC9, than did Cincinnati (USA) donors. Spanish blood donors (n=162) also exhibited elevated responses to MsgC1, MsgC8 and MsgC9 as compared with Spanish HIV(+) (n=164) patients. HIV(+) patients who had Pneumocystis pneumonia (PcP(+)) exhibited a higher response to MsgC8 than did HIV(+) PcP(-) patients. These data show that geographical location plays a role in responsiveness to Msg fragments. Additionally, these fragments have utility in differentiating HIV(+) PcP and HIV(+) PcP(+) among patient populations.
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Affiliation(s)
- K Daly
- Department of Internal Medicine, Division of Infectious Diseases, University of Cincinnati, Cincinnati, Ohio 45267-0560, USA.
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The occurrence of Pneumocystis jirovecii in people from three different age groups of Warsaw (Poland) community. Acta Parasitol 2008. [DOI: 10.2478/s11686-008-0003-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AbstractThe three age groups of people from Warsaw: children, young adults and elderly people were examined for the prevalence of infection with Pneumocystis jirovecii. Nested PCR was used to amplify fragment of mitochondrial large subunit rRNA of the fungus in samples of oropharyngeal swabs. Nineteen (12.8%) of the 148 examined samples were positive for DNA of P. jirovecii. The samples collected from children were more often positive than the samples from young adults (p = 0.003) or from both groups of adults (p = 0.0029). Moreover, among adults (n = 99) proportion of infected women (n = 6; 12.5%) was significantly higher than men (n = 1; 2%). Results of the research confirm the high prevalence of Pneumocystis infection in children and indirectly point out to children as a possible source of infection for older people.
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Morris A, Wei K, Afshar K, Huang L. Epidemiology and Clinical Significance ofPneumocystisColonization. J Infect Dis 2008; 197:10-7. [DOI: 10.1086/523814] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Montes-Cano MA, de la Horra C, Dapena FJ, Mateos I, Friaza V, Respaldiza N, Muñoz-Lobato F, Medrano FJ, Calderon EJ, Varela JM. Dynamic colonisation by different Pneumocystis jirovecii genotypes in cystic fibrosis patients. Clin Microbiol Infect 2007; 13:1008-11. [PMID: 17711486 DOI: 10.1111/j.1469-0691.2007.01789.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although asymptomatic carriers of Pneumocystis jirovecii with cystic fibrosis (CF) have been described previously, the molecular epidemiology of P. jirovecii in CF patients has not yet been clarified. This study identified the distribution and dynamic evolution of P. jirovecii genotypes based on the mitochondrial large-subunit (mt LSU) rRNA gene. The mt LSU rRNA genotypes of P. jirovecii isolates in 33 respiratory samples from CF patients were investigated using nested PCR and direct sequencing. Three different genotypes were detected: 36.3% genotype 1 (85C/248C); 15.1% genotype 2 (85A/248C); 42.4% genotype 3 (85T/248C); and 6% mixed genotypes. Patients studied during a 1-year follow-up period showed a continuous colonisation/clearance cycle involving P. jirovecii and an accumulative tendency to be colonised with genotype 3.
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Affiliation(s)
- M A Montes-Cano
- Department of Internal Medicine, Virgen Del Rocio University Hospital, Seville, Spain.
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Larsen HH, von Linstow ML, Lundgren B, Høgh B, Westh H, Lundgren JD. Primary pneumocystis infection in infants hospitalized with acute respiratory tract infection. Emerg Infect Dis 2007; 13:66-72. [PMID: 17370517 PMCID: PMC2725833 DOI: 10.3201/eid1301.060315] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Acquisition of Pneumocystis jirovecii infection early in life has been confirmed by serologic studies. However, no evidence of clinical illness correlated with the primary infection has been found in immunocompetent children. We analyzed 458 nasopharyngeal aspirates from 422 patients hospitalized with 431 episodes of acute respiratory tract infection (RTI) by using a real-time PCR assay. In 68 episodes in 67 infants, P. jirovecii was identified. The odds ratio (95% confidence interval) of a positive signal compared with the first quartile of age (7-49 days) was 47.4 (11.0-203), 8.7 (1.9-39.7), and 0.6 (0.1-6.7) for infants in the second (50-112 days), third (113-265 days), and fourth (268-4,430 days) age quartiles, respectively. Infants with an episode of upper RTI (URTI) were 2.0 (1.05-3.82) times more likely to harbor P. jirovecii than infants with a lower RTI. P. jirovecii may manifest itself as a self-limiting URTI in infants, predominantly those 1.5-4 months of age.
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Varela Aguilar JM, Medrano Ortega FJ, Calderón Sandubete E. Pneumocystis jirovecii: un nuevo nombre para un viejo patógeno. Rev Clin Esp 2006; 206:278-80. [PMID: 16762291 DOI: 10.1157/13088588] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pneumonia due to Pneumocystis is an important cause of morbidity-mortality among immunodepressed patients, above all with human immunodeficiency virus infection and finally in patients with transplants, oncology patients and those subjected to drug immunodepression. Its lack of capacity to grow in the usual culture mediums has hindered knowledge on many aspects of this infection (transmission, acquisition mode, infection sources). However, the incorporation of molecular biology tools in recent years has made it possible to go deeper into the understanding of the epidemiology, biology and characteristics of the infection by this pathogen. These advances have led to the modification of the taxonomic classification of this atypical fungus and change in the name of the Pneumocystis responsible for the infection in humans, which is now called Pneumocystis jirovecii. During this article, we will show some of the most recent advances in the knowledge of the human pneumocystosis.
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Affiliation(s)
- J M Varela Aguilar
- Servicio de Medicina Interna, Hospital Universitario Virgen del Rocío, Sevilla, España.
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Respaldiza N, Montes-Cano MA, Dapena FJ, de la Horra C, Mateos I, Medrano FJ, Calderon E, Varela JM. Prevalence of colonisation and genotypic characterisation of Pneumocystis jirovecii among cystic fibrosis patients in Spain. Clin Microbiol Infect 2005; 11:1012-5. [PMID: 16307556 DOI: 10.1111/j.1469-0691.2005.01276.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Pneumocystis jirovecii colonisation may occur among cystic fibrosis (CF) patients because of their underlying pulmonary disease. A wide epidemiological analysis was performed among CF patients from Spain to assess the prevalence of P. jirovecii colonisation and the distribution of different genotypes. P. jirovecii was identified by nested PCR targeting the mitochondrial large-subunit rRNA gene from sputum samples or oropharyngeal washes. The genotype was determined by direct sequencing. The prevalence of P. jirovecii colonisation among 88 consecutive CF patients was 21.5%. The polymorphisms identified were 85C/248C (45.4%), 85T/248C (27.2%) and 85A/248C (18.1%); in one case, a mix of genotypes was found. Colonisation was more frequent in subjects aged < 18 years (25.5% vs. 15.1%). Among the patients studied, 20.8% received treatment with azithromycin; all of these patients were colonised with P. jirovecii, but none developed Pneumocystis pneumonia (PcP) during a 1-year follow-up period. Concordance in the colonisation status of siblings suggested a common source of infection or person-to-person transmission.
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Affiliation(s)
- N Respaldiza
- Department of Internal Medicine and Cystic Fibrosis Unit, Virgen del Rocío University Hospital, Seville, Spain
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Peterson JC, Cushion MT. Pneumocystis: not just pneumonia. Curr Opin Microbiol 2005; 8:393-8. [PMID: 15996508 DOI: 10.1016/j.mib.2005.06.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2005] [Accepted: 06/20/2005] [Indexed: 11/16/2022]
Abstract
Once known exclusively as the agents of severe pneumonia in immunocompromised individuals, Pneumocystis spp. are now being associated with asymptomatic carriage in hosts that do not have profound immune debilitation. In the absence of a cultivation system, polymerase chain reaction and histological studies have identified Pneumocystis in neonatal populations, in pregnant women and in other patients that have chronic underlying disease processes. These findings in humans and in experimental animal models indicate the presence of potential reservoirs of infection, and provide insights into the transmission of this fungus. Also, the role of Pneumocystis has been investigated as a possible co-morbidity factor.
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Affiliation(s)
- J Chad Peterson
- Department of Infectious Disease, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0560, USA
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