1
|
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.
Collapse
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;
| |
Collapse
|
2
|
Therapy and Management of Pneumocystis jirovecii Infection. J Fungi (Basel) 2018; 4:jof4040127. [PMID: 30469526 PMCID: PMC6313306 DOI: 10.3390/jof4040127] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/08/2018] [Accepted: 11/11/2018] [Indexed: 12/21/2022] Open
Abstract
The rates of Pneumocystis pneumonia (PcP) are increasing in the HIV-negative susceptible population. Guidance for the prophylaxis and treatment of PcP in HIV, haematology, and solid-organ transplant (SOT) recipients is available, although for many other populations (e.g., auto-immune disorders) there remains an urgent need for recommendations. The main drug for both prophylaxis and treatment of PcP is trimethoprim/sulfamethoxazole, but resistance to this therapy is emerging, placing further emphasis on the need to make a mycological diagnosis using molecular based methods. Outbreaks in SOT recipients, particularly renal transplants, are increasingly described, and likely caused by human-to-human spread, highlighting the need for efficient infection control policies and sensitive diagnostic assays. Widespread prophylaxis is the best measure to gain control of outbreak situations. This review will summarize diagnostic options, cover prophylactic and therapeutic management in the main at risk populations, while also covering aspects of managing resistant disease, outbreak situations, and paediatric PcP.
Collapse
|
3
|
Miller RF, Huang L, Walzer PD. The Relationship between Pneumocystis Infection in Animal and Human Hosts, and Climatological and Environmental Air Pollution Factors: A Systematic Review. ACTA ACUST UNITED AC 2018; 2. [PMID: 30815637 PMCID: PMC6388696 DOI: 10.21926/obm.genet.1804045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Background: Over the past decade, there has been rising interest in the interaction of Pneumocystis with the environment. This interest has arisen in part from the demonstration that environmental factors have important effects on the viability and transmission of microbes, including Pneumocystis. Environmental factors include climatological factors such as temperature, humidity, and precipitation, and air pollution factors including carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter. Methods: We undertook a systematic review in order to identify environmental factors associated with Pneumocystis infection or PCP, and their effects on human and animal hosts. Results: The systematic review found evidence of associations between Pneumocystis infection in animal and human hosts, and climatological and air pollution factors. Data from human studies infers that rather than a seasonal association, presentation with PCP appears to be highest when the average temperature is between 10 and 20°C. There was evidence of an association with hospitalization with PCP and ambient air pollution factors, as well as evidence of an effect of air pollution on both systemic and bronchoscopic lavage fluid humoral responses to Pneumocystis. Interpretation of human studies was confounded by possible genetically-determined predisposition to, or protection from infection. Conclusions: This systematic review provides evidence of associations between Pneumocystis infection in both animal and human hosts, and climatological and environmental air pollution factors. This information may lead to an improved understanding of the conditions involved in transmission of Pneumocystis in both animal and human hosts. Such knowledge is critical to efforts aimed at prevention.
Collapse
Affiliation(s)
- Robert F Miller
- Centre for Clinical Research in Infection and Sexual Health, Institute for Global Health, University College London, London WC1E 6JB, UK.,Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK.,Bloomsbury Clinic, Mortimer Market Centre, Central & North West London NHS Foundation Trust, London WC1E 6JB, UK.,HIV Services, Royal Free London NHS Foundation Trust, London NW3 2QG, UK
| | - Laurence Huang
- Division of Pulmonary and Critical Care Medicine, Zuckerberg San Francisco General Hospital and Trauma Center, University of California, San Francisco, CA 94110, USA; .,HIV, Infectious Diseases, and Global Medicine Division, Zuckerberg San Francisco General Hospital and Trauma Center, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Peter D Walzer
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA;
| |
Collapse
|
4
|
de Boer MGJ, Walzer PD, Mori S. Healthcare related transmission of Pneumocystis pneumonia: From key insights toward comprehensive prevention. Transpl Infect Dis 2018; 20:e12942. [PMID: 29873156 DOI: 10.1111/tid.12942] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 04/21/2018] [Accepted: 05/28/2018] [Indexed: 12/15/2022]
Abstract
In at risk populations, Pneumocystis pneumonia (PCP) may occur as a solitary event as well as in a cluster- or outbreak setting due to interpatient transmission of Pneumocystis jirovecii. Despite the data and insights obtained from studies of outbreaks of PCP, the development and implementation of comprehensive recommendations for the prevention of healthcare related transmission of P. jirovecii have been delayed. Both optimization of chemoprophylaxis strategies as well as combination with prudent use of isolation precautions are warranted to achieve this goal. The rationale of the available measures for the prevention of PCP should be viewed in the context of what is currently known about the complex biology and epidemiology of P. jirovecii. From there, phased but practical prevention strategies can be deducted to balance the efforts, costs and negative consequences of chemoprophylaxis and isolation precautions with the beneficial effect of preventing healthcare related transmission of P. jirovecii and development of PCP.
Collapse
Affiliation(s)
- Mark G J de Boer
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter D Walzer
- Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Shunsuke Mori
- Department of Rheumatology, Clinical Research Center for Rheumatic Diseases, NHO Kumamoto Saishunsou National Hospital, Kumamoto, Japan
| |
Collapse
|
5
|
Kruizinga MD, Bresters D, Smiers FJ, Lankester AC, Bredius RGM. The use of intravenous pentamidine for the prophylaxis of Pneumocystis pneumonia in pediatric patients. Pediatr Blood Cancer 2017; 64. [PMID: 28074607 DOI: 10.1002/pbc.26453] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 11/25/2016] [Accepted: 12/18/2016] [Indexed: 11/06/2022]
Abstract
Pneumocystis jiroveci pneumonia was common in the immunocompromised host before the widespread use of prophylaxis. When trimethoprim-sulfamethoxazole is not tolerated, prophylaxis with intravenous pentamidine (IVP) may be initiated. We performed a retrospective analysis of all pediatric patients who received IVP regarding efficacy, safety, and reason for initiation. Of 106 patients included in our analysis, one patient tested positive for Pneumocystis DNA. Adverse events were reported in 18% of IVP courses, and main reason for initiation was cytopenia (59%). We found IVP to be effective and safe, and recommend the use of IVP in pediatric patients in whom first-line prophylaxis is contraindicated.
Collapse
Affiliation(s)
- Matthijs D Kruizinga
- Department of Pediatric Immunology-Infections and Stem Cell Transplantation, Leiden University Medical Center, Leiden, The Netherlands
| | - Dorine Bresters
- Department of Pediatric Immunology-Infections and Stem Cell Transplantation, Leiden University Medical Center, Leiden, The Netherlands
| | - Frans J Smiers
- Department of Pediatric Immunology-Infections and Stem Cell Transplantation, Leiden University Medical Center, Leiden, The Netherlands
| | - Arjan C Lankester
- Department of Pediatric Immunology-Infections and Stem Cell Transplantation, Leiden University Medical Center, Leiden, The Netherlands
| | - Robbert G M Bredius
- Department of Pediatric Immunology-Infections and Stem Cell Transplantation, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
6
|
Tadros S, Teichtahl AJ, Ciciriello S, Wicks IP. Pneumocystis jirovecii pneumonia in systemic autoimmune rheumatic disease: A case-control study. Semin Arthritis Rheum 2016; 46:804-809. [PMID: 27814896 DOI: 10.1016/j.semarthrit.2016.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 09/19/2016] [Accepted: 09/20/2016] [Indexed: 10/20/2022]
Abstract
INTRODUCTION AND OBJECTIVES Pneumocystis jirovecii pneumonia (PJP) is an opportunistic fungal infection that affects the immunocompromised. Patients with systemic autoimmune rheumatic disease are increasingly recognised as an at-risk clinical population with a high mortality. This case-control study examined differences in the characteristics and peripheral blood parameters between patients with systemic autoimmune rheumatic disease who developed PJP and gender, age and disease-matched controls. METHODS Historical data collected between 2002 and 2013 at the Royal Melbourne Hospital, Australia were reviewed. Cases were defined by having a systemic autoimmune rheumatic disease and a diagnosis of PJP (either a positive toluidine blue O stain or P. jirovecii PCR, with a concurrent respiratory illness that was clinically consistent with PJP). Controls were matched for age, gender and disease in a 4:1 ratio. Peripheral blood results were retrieved from an in-house pathology database. Clinical information including glucocorticoid exposure, PJP prophylaxis, comorbidities and month of admission were retrieved from medical notes. RESULTS After adjustment for corticosteroid exposure and C-reactive protein, lymphocyte count on admission (0.4 vs. 1.3; p = 0.04) and at nadir (0.2 vs. 0.8 × 109/L; p = 0.05) was significantly lower in cases than in controls. Cases (n = 11) were more frequently Caucasian rather than non-Caucasian (81.8% vs. 65.9%; p = 0.04). In addition, cases more commonly presented in autumn (March to May) than in other seasons (OR = 7.3; 95% CI: 1.4-38.7; p = 0.02). CONCLUSION These data demonstrate that patients with systemic autoimmune rheumatic disease who develop PJP have significantly greater lymphopenia than age, gender and disease-matched controls, independent of corticosteroid exposure, as well as a potential ethnicity and seasonal predilection to PJP. This may help to inform prophylactic guidelines for PJP in these patients.
Collapse
Affiliation(s)
- Susan Tadros
- Department of Rheumatology, The Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Andrew J Teichtahl
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Alfred Hospital, Monash University, Melbourne, Victoria, Australia
| | - Sabina Ciciriello
- Department of Rheumatology, The Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Ian P Wicks
- Department of Rheumatology, The Royal Melbourne Hospital, Parkville, Victoria, Australia; Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville 3050, Victoria, Australia; University of Melbourne, Department of Medical Biology, Parkville, Victoria, Australia.
| |
Collapse
|
7
|
Ronit A, Klitbo DM, Kildemoes AO, Benfield T, Gerstoft J, Vestbo J, Jensen JS, Kurtzhals J, Nielsen SD. Absence of Pneumocystis jirovecii Colonization in Human Immunodeficiency Virus-Infected Individuals With and Without Airway Obstruction and With Undetectable Viral Load. Open Forum Infect Dis 2016; 3:ofw044. [PMID: 27006967 PMCID: PMC4800465 DOI: 10.1093/ofid/ofw044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 02/16/2016] [Indexed: 11/25/2022] Open
Abstract
Pneumocystis jirovecii colonization has been associated with non-acquired immune deficiency syndrome (AIDS) pulmonary comorbidity. We used spirometry to measure pulmonary function and analyzed oral wash specimens by quantitative polymerase chain reaction (PCR), targeting the large mitochondrial ribosomal subunit. For sensitivity control, a blinded subsample was subjected to touch-down PCRs, targeting both large and small ribosomal subunits and the major surface glycoprotein. Pneumocystis jirovecii deoxyribonucleic acid (DNA) was detected in 1 of 156 (95% confidence interval, .1%–3.5%) virologically suppressed human immunodeficiency virus (HIV)-infected individuals confirmed by all PCR methods. Thus, prevalence of P jirovecii colonization was low and unlikely to be a major cause of pulmonary comorbidity in this group of well treated HIV-infected individuals.
Collapse
Affiliation(s)
- Andreas Ronit
- Viro-immunology Research Unit, Department of Infectious Diseases , Copenhagen University Hospital
| | - Ditte Marie Klitbo
- Viro-immunology Research Unit, Department of Infectious Diseases , Copenhagen University Hospital
| | - Anna Overgaard Kildemoes
- Centre for Medical Parasitology, Department of Clinical Microbiology KMA, Copenhagen University Hospital
| | - Thomas Benfield
- Department of Infectious Diseases , Copenhagen University Hospital , Hvidovre , Denmark
| | - Jan Gerstoft
- Viro-immunology Research Unit, Department of Infectious Diseases , Copenhagen University Hospital
| | - Jørgen Vestbo
- Centre for Respiratory Medicine and Allergy , University Hospital South Manchester NHS Foundation Trust and The University of Manchester , United Kingdom
| | - Jørgen Skov Jensen
- Department of Microbiology and Infection Control , Statens Serum Institut , Copenhagen
| | - Jørgen Kurtzhals
- Department of Immunology and Microbiology , University of Copenhagen , Denmark
| | - Susanne Dam Nielsen
- Viro-immunology Research Unit, Department of Infectious Diseases , Copenhagen University Hospital
| |
Collapse
|
8
|
Iriart X, Bouar ML, Kamar N, Berry A. Pneumocystis Pneumonia in Solid-Organ Transplant Recipients. J Fungi (Basel) 2015; 1:293-331. [PMID: 29376913 PMCID: PMC5753127 DOI: 10.3390/jof1030293] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 12/27/2022] Open
Abstract
Pneumocystis pneumonia (PCP) is well known and described in AIDS patients. Due to the increasing use of cytotoxic and immunosuppressive therapies, the incidence of this infection has dramatically increased in the last years in patients with other predisposing immunodeficiencies and remains an important cause of morbidity and mortality in solid-organ transplant (SOT) recipients. PCP in HIV-negative patients, such as SOT patients, harbors some specificity compared to AIDS patients, which could change the medical management of these patients. This article summarizes the current knowledge on the epidemiology, risk factors, clinical manifestations, diagnoses, prevention, and treatment of Pneumocystis pneumonia in solid-organ transplant recipients, with a particular focus on the changes caused by the use of post-transplantation prophylaxis.
Collapse
Affiliation(s)
- Xavier Iriart
- Department of Parasitology-Mycology, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Institut Fédératif de biologie (IFB), 330 avenue de Grande Bretagne, TSA 40031, Toulouse 31059, France.
- INSERM U1043, Toulouse F-31300, France.
- CNRS UMR5282, Toulouse F-31300, France.
- Université de Toulouse, UPS, Centre de Physiopathiologie de Toulouse Purpan (CPTP), Toulouse F-31300, France.
| | - Marine Le Bouar
- Department of Parasitology-Mycology, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Institut Fédératif de biologie (IFB), 330 avenue de Grande Bretagne, TSA 40031, Toulouse 31059, France.
- INSERM U1043, Toulouse F-31300, France.
- CNRS UMR5282, Toulouse F-31300, France.
- Université de Toulouse, UPS, Centre de Physiopathiologie de Toulouse Purpan (CPTP), Toulouse F-31300, France.
| | - Nassim Kamar
- INSERM U1043, Toulouse F-31300, France.
- Université de Toulouse, UPS, Centre de Physiopathiologie de Toulouse Purpan (CPTP), Toulouse F-31300, France.
- Department of Nephrology and Organ Transplantation, CHU Rangueil, TSA 50032, Toulouse 31059, France.
| | - Antoine Berry
- Department of Parasitology-Mycology, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Institut Fédératif de biologie (IFB), 330 avenue de Grande Bretagne, TSA 40031, Toulouse 31059, France.
- INSERM U1043, Toulouse F-31300, France.
- CNRS UMR5282, Toulouse F-31300, France.
- Université de Toulouse, UPS, Centre de Physiopathiologie de Toulouse Purpan (CPTP), Toulouse F-31300, France.
| |
Collapse
|
9
|
Pneumocystis pneumonia in HIV-positive patients in Spain: epidemiology and environmental risk factors. J Int AIDS Soc 2015; 18:19906. [PMID: 25997453 PMCID: PMC4440874 DOI: 10.7448/ias.18.1.19906] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 04/22/2015] [Accepted: 04/22/2015] [Indexed: 11/21/2022] Open
Abstract
Introduction Specific environmental factors may play a role in the development of Pneumocystis pneumonia (PCP) in HIV-positive patients. The aim of this study was to estimate the PCP incidence and mortality in hospitalized HIV-positive patients in Spain during the combination antiretroviral therapy (cART) era (1997 to 2011), as well as to analyze the climatological factors and air pollution levels in relation to hospital admissions and deaths. Methods We carried out a retrospective study. Data were collected from the National Hospital Discharge Database and the State Meteorological Agency of Spain. A case-crossover analysis was applied to identify environmental risk factors related to hospitalizations and deaths. For each patient, climatic factors and pollution levels were assigned based on readings from the nearest meteorological station to his or her postal code. Results There were 13,139 new PCP diagnoses and 1754 deaths in hospitalized HIV-positive patients from 1997 to 2011. The PCP incidence (events per 1000 person-years) dropped from 11.6 in 1997 to 2000, to 5.4 in 2004 to 2011 (p<0.001). The mortality (events per 10,000 person-years) also decreased from 14.3 in 1997 to 2000, to 7.5 in 2004 to 2011 (p<0.001). Most hospital admissions and deaths occurred in the winter season and the fewest occurred in the summer, overlapping respectively with the lowest and highest temperatures of the year in Spain. Moreover, lower temperatures prior to PCP admission, as well as higher concentrations of NO2 and particulate matter up to 10 m in size (PM10) at the time of admission were associated with higher likelihoods of hospital admission due to PCP when two weeks, one month, 1.5 months or two months were used as controls (p<0.01). Furthermore, higher concentrations of ozone at one month (p=0.007), 1.5 months (p<0.001) and two months (p=0.006) prior to admission were associated with higher likelihoods of hospital admission with PCP. For PCP-related deaths, lower temperatures prior to admission and higher concentrations of atmospheric PM10 at the time of admission were related to higher likelihood of death when two weeks, one month and 1.5 months were used as controls (p<0.05). Conclusions PCP was a significant health problem in the cART era (1997 to 2011), and PCP epidemiology was adversely influenced by colder climatological factors and higher ambient air pollution levels.
Collapse
|
10
|
Debourgogne A, Favreau S, Ladrière M, Bourry S, Machouart M. Characteristics of Pneumocystis pneumonia in Nancy from January 2007 to April 2011 and focus on an outbreak in nephrology. J Mycol Med 2014; 24:19-24. [DOI: 10.1016/j.mycmed.2013.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 10/07/2013] [Accepted: 10/28/2013] [Indexed: 01/15/2023]
|
11
|
Walzer PD. The ecology of pneumocystis: perspectives, personal recollections, and future research opportunities. J Eukaryot Microbiol 2013; 60:634-45. [PMID: 24001365 DOI: 10.1111/jeu.12072] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 07/17/2013] [Accepted: 07/17/2013] [Indexed: 11/28/2022]
Abstract
I am honored to receive the second Lifetime Achievement Award by International Workshops on Opportunistic Protists and to give this lecture. My research involves Pneumocystis, an opportunistic pulmonary fungus that is a major cause of pneumonia ("PcP") in the immunocompromised host. I decided to focus on Pneumocystis ecology here because it has not attracted much interest. Pneumocystis infection is acquired by inhalation, and the cyst stage appears to be the infective form. Several fungal lung infections, such as coccidiomycosis, are not communicable, but occur by inhaling < 5 μm spores from environmental sources (buildings, parks), and can be affected by environmental factors. PcP risk factors include environmental constituents (temperature, humidity, SO2 , CO) and outdoor activities (camping). Clusters of PcP have occurred, but no environmental source has been found. Pneumocystis is communicable and outbreaks of PcP, especially in renal transplant patients, are an ongoing problem. Recent evidence suggests that most viable Pneumocystis organisms detected in the air are confined to a patient's room. Further efforts are needed to define the risk of Pneumocystis transmission in health care facilities; to develop more robust preventive measures; and to characterize the effects of climatological and air pollutant factors on Pneumocystis transmission in animal models similar to those used for respiratory viruses.
Collapse
Affiliation(s)
- Peter D Walzer
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, 45267-0560; Research Service, Veterans Affairs Medical Center, Cincinnati, Ohio, 45220
| |
Collapse
|
12
|
Djawe K, Levin L, Swartzman A, Fong S, Roth B, Subramanian A, Grieco K, Jarlsberg L, Miller RF, Huang L, Walzer PD. Environmental risk factors for Pneumocystis pneumonia hospitalizations in HIV patients. Clin Infect Dis 2012; 56:74-81. [PMID: 23042978 DOI: 10.1093/cid/cis841] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Pneumocystis pneumonia (PcP) is the second leading cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected patients in the United States. Although the host risk factors for the development of PcP are well established, the environmental (climatological, air pollution) risk factors are poorly understood. The major goal of this study was to determine the environmental risk factors for admissions of HIV-positive patients with PcP to a single medical center. METHODS Between 1997 and 2008, 457 HIV-positive patients with microscopically confirmed PcP were admitted to the San Francisco General Hospital. A case-crossover design was applied to identify environmental risk factors for PcP hospitalizations. Climatological and air pollution data were collected from the Environmental Protection Agency and Weather Warehouse databases. Conditional logistic regression was used to evaluate the association of each environmental factor and PcP hospital admission. RESULTS Hospital admissions were significantly more common in the summer than in the other seasons. Increases in temperature and sulfur dioxide levels were independently associated with hospital admissions for PcP, but the effects of sulfur dioxide were modified by increasing carbon monoxide levels. CONCLUSIONS This study identifies both climatological and air pollution constituents as independent risk factors for hospitalization of HIV-positive patients with PcP in San Francisco. Thus, the environmental effects on PcP are more likely complex than previously thought. Further studies are needed to understand how these factors exert their effects and to determine if these factors are associated with PcP in other geographic locations.
Collapse
Affiliation(s)
- Kpandja Djawe
- Veterans Affairs Medical Center, Cincinnati, OH 45267-0560, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Characterizing Pneumocystis in the lungs of bats: understanding Pneumocystis evolution and the spread of Pneumocystis organisms in mammal populations. Appl Environ Microbiol 2012; 78:8122-36. [PMID: 23001662 DOI: 10.1128/aem.01791-12] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bats belong to a wide variety of species and occupy diversified habitats, from cities to the countryside. Their different diets (i.e., nectarivore, frugivore, insectivore, hematophage) lead Chiroptera to colonize a range of ecological niches. These flying mammals exert an undisputable impact on both ecosystems and circulation of pathogens that they harbor. Pneumocystis species are recognized as major opportunistic fungal pathogens which cause life-threatening pneumonia in severely immunocompromised or weakened mammals. Pneumocystis consists of a heterogeneous group of highly adapted host-specific fungal parasites that colonize a wide range of mammalian hosts. In the present study, 216 lungs of 19 bat species, sampled from diverse biotopes in the New and Old Worlds, were examined. Each bat species may be harboring a specific Pneumocystis species. We report 32.9% of Pneumocystis carriage in wild bats (41.9% in Microchiroptera). Ecological and behavioral factors (elevation, crowding, migration) seemed to influence the Pneumocystis carriage. This study suggests that Pneumocystis-host association may yield much information on Pneumocystis transmission, phylogeny, and biology in mammals. Moreover, the link between genetic variability of Pneumocystis isolated from populations of the same bat species and their geographic area could be exploited in terms of phylogeography.
Collapse
|
14
|
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.
Collapse
|
15
|
Pederiva MA, Wissmann G, Friaza V, Morilla R, de La Horra C, Montes-Cano MA, Goldani LZ, Calderón EJ, Prolla JC. High prevalence ofPneumocystis jiroveciicolonization in Brazilian cystic fibrosis patients. Med Mycol 2012; 50:556-60. [DOI: 10.3109/13693786.2011.645892] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
16
|
Gutiérrez S, Respaldiza N, Campano E, Martínez-Risquez MT, Calderón EJ, De La Horra C. Pneumocystis jirovecii colonization in chronic pulmonary disease. Parasite 2011; 18:121-6. [PMID: 21678787 PMCID: PMC3671413 DOI: 10.1051/parasite/2011182121] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Pneumocystis jirovecii causes pneumonia in immunosuppressed individuals. However, it has been reported the detection of low levels of Pneumocystis DNA in patients without signs and symptoms of pneumonia, which likely represents colonization. Several studies performed in animals models and in humans have demonstrated that Pneumocystis induces a local and a systemic response in the host. Since P. jirovecii colonization has been found in patients with chronic pulmonary diseases it has been suggested that P. jirovecii may play a role in the physiopathology and progression of those diseases. In this report we revise P. jirovecii colonization in different chronic pulmonary diseases such us, chronic obstructive pulmonary disease, interstitial lung diseases, cystic fibrosis and lung cancer.
Collapse
Affiliation(s)
- S Gutiérrez
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain.
| | | | | | | | | | | |
Collapse
|
17
|
de Boer MGJ, de Fijter JW, Kroon FP. Outbreaks and clustering of Pneumocystis pneumonia in kidney transplant recipients: a systematic review. Med Mycol 2011; 49:673-80. [PMID: 21453224 DOI: 10.3109/13693786.2011.571294] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
From 1980 onwards, an increasing number of outbreaks of Pneumocystis pneumonia (PCP) among kidney transplant recipients have been reported. The cause of these outbreaks is unclear and different explanations have been provided. We performed a systematic review to provide a comprehensive overview of the epidemiologic characteristics as well as the involved clinical risk factors. A total of 15 peer-reviewed English language articles published from 1980 onward were included. Outbreak settings were all marked by absence of adequate chemoprophylaxis, frequent inter-patient contacts and lack of isolation measures taken during hospitalization of PCP cases. PCP-associated mortality rates significantly decreased from a weighted mean of 38% before 1990 to 19% and 13% in the following two decades. Clinical risk factors for PCP in outbreak settings were largely similar to non-outbreak settings. Genotyping by multilocus sequence typing (MLST) or comparison of the internal transcribed spacer (ITS) regions 1 and 2 showed that the outbreaks are most frequently caused by a predominant or a single Pneumocystis strain. Pooled epidemiological data and genotyping results strongly support the theory that interhuman transmission of Pneumocystis occurred. No seasonal trend was noted. The results emphasize the need for chemoprophylaxis in kidney transplant recipients despite a low baseline incidence of PCP in this population, and support the current CDC recommendation with regard to isolation of patients with PCP during hospitalization.
Collapse
Affiliation(s)
- Mark G J de Boer
- Department of Infectious Diseases, Leiden University Medical Center, the Netherlands.
| | | | | |
Collapse
|
18
|
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.
Collapse
Affiliation(s)
- Kpandja Djawe
- Department of Environmental Health, University of Cincinnati, Cincinnati, Ohio, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Calderón EJ, Friaza V, Dapena FJ, de La Horra C. Pneumocystis jirovecii and cystic fibrosis. Med Mycol 2011; 48 Suppl 1:S17-21. [PMID: 21067325 DOI: 10.3109/13693786.2010.505205] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Pneumocystis jirovecii is an atypical opportunistic fungus with lung tropism and worldwide distribution that causes pneumonia in immunosuppressed individuals. The development of sensitive molecular techniques has led to the recognition of a colonization or carrier state of P. jirovecii, in which low levels of the organism are detected in persons who do not have pneumonia. Pneumocystis colonization has been described in individuals with various lung diseases, and accumulating evidence suggests that it may be a relevant issue with potential clinical impact. Only a few published studies carried out in Europe have evaluated the prevalence of Pneumocystis colonization in patients with cystic fibrosis, reporting ranges from 1.3-21.6%. The evolution of P. jirovecii colonization in cystic fibrosis patients is largely unknown. In a longitudinal study, none of the colonized patients developed pneumonia during a 1-year follow-up. Since patients with cystic fibrosis could act as major reservoirs and sources of infection for susceptible individuals further research is thus warranted to assess the true scope of the problem and to design rational preventive strategies if necessary. Moreover, it's necessary to elucidate the role of P. jirovecii infection in the natural history of cystic fibrosis in order to improve the clinical management of this disease.
Collapse
Affiliation(s)
- Enrique J Calderón
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, CIBER de Epidemiología y Salud Pública, Seville, Spain.
| | | | | | | |
Collapse
|
20
|
Miller RF, Evans HER, Copas AJ, Huggett JF, Edwards SG, Walzer PD. Seasonal variation in mortality of Pneumocystis jirovecii pneumonia in HIV-infected patients. Int J STD AIDS 2011; 21:497-503. [PMID: 20852200 DOI: 10.1258/ijsa.2010.010148] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A seasonal variation in the presentation of Pneumocystis jirovecii pneumonia (PCP) has been reported and a previous study from this centre noted a seasonal variation in mortality rates. This study examined seasonal influences (including climatic factors) within-host factors (clinical and laboratory-derived variables), the infectious burden of P. jirovecii in bronchoalveolar lavage (BAL) fluid, the presence of dihydropteroate synthase (DHPS) mutations in P. jirovecii, variations in knowledge and skills of junior medical staff, and mortality in 547 episodes of PCP occurring in 494 HIV-infected patients. The overall mortality rate was 13.5%. There was a seasonal variation in mortality: highest in autumn (21.2%) and lowest in spring (9.7%), P = 0.047. After adjustment was made for prognostic factors previously identified as being associated with mortality (increasing patient age, second/third episode of PCP, low haemoglobin, low PaO(2), presence of medical co-morbidity and pulmonary Kaposi sarcoma), there was no seasonal association with mortality, P = 0.249. The quantity of P. jirovecii DNA in BAL fluid showed no evidence of seasonal variation, P = 0.67; DHPS mutations were identified with equal frequency in each season and the mortality rate for February and August (when junior medical staff arrive in new posts) was 16.7%, only slightly greater than for other months (13.0%).
Collapse
Affiliation(s)
- R F Miller
- Centre for Sexual Health and HIV Research, Research Department of Infection and Population Health, Division of Population Health, University College London, UK.
| | | | | | | | | | | |
Collapse
|