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Encephalitozoon spp. as a potential human pathogen. POSTEP HIG MED DOSW 2022. [DOI: 10.2478/ahem-2022-0005] [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] Open
Abstract
Abstract
Encephalitzoon spp. are microsporidia, and intracellular opportunistic pathogens. The hosts of these pathogens include vertebrates, invertebrates, and certain protozoa. In people microsporidia may be opportunistic pathogens for immunocompromised patients (with AIDS or after organ transplantation). Infection with these microorganisms was also described in persons with diarrhea and corneal diseases.
The species causing rare infections in humans, Encephalitozooncuniculi, had previously been described from animal hosts. However, several new microsporidial species, including E. intestinalis and E. hellem, have been discovered in humans, raising the question of their natural origin. Vertebrate animals are now identified as hosts for all three microsporidial species infecting humans, implying a zoonotic nature of these microorganisms. Molecular studies have identified phenotypic and/or genetic variability within these species, indicating that they are not uniform, and have allowed the question of their zoonotic potential to be addressed. The focus of this review is to present the zoonotic potential of E. intestinalis, E. cuniculi, and E. hellem.
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Figuerêdo Moreira I, Marcelino Alvares-Saraiva A, Cristin Pérez E, Guilherme Xavier J, Denelle Spadacci-Morena D, Silva de Araújo R, Ricardo Dell'Armelina Rocha P, Anete Lallo M. Opportunistic pneumonia caused by E. cuniculi in mice immunosuppressed with cyclophosphamide. Immunobiology 2022; 227:152194. [DOI: 10.1016/j.imbio.2022.152194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 02/15/2022] [Accepted: 02/27/2022] [Indexed: 12/01/2022]
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Abstract
Microsporidia are pathogenic organism related to fungi. They cause infections in a wide variety of mammals as well as in avian, amphibian, and reptilian hosts. Many microsporidia species play an important role in the development of serious diseases that have significant implications in human and veterinary medicine. While microsporidia were originally considered to be opportunistic pathogens in humans, it is now understood that infections also occur in immune competent humans. Encephalitozoon cuniculi, Encephalitozoon intestinalis, and Enterocytozoon bieneusi are primarily mammalian pathogens. However, many other species of microsporidia that have some other primary host that is not a mammal have been reported to cause sporadic mammalian infections. Experimental models and observations in natural infections have demonstrated that microsporidia can cause a latent infection in mammalian hosts. This chapter reviews the published studies on mammalian microsporidiosis and the data on chronic infections due to these enigmatic pathogens.
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Affiliation(s)
- Bohumil Sak
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic.
| | - Martin Kváč
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Agriculture, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
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Peixoto D, Prestes DP. Parasitic Infections of the Stem Cell Transplant Recipient and the Hematologic Malignancy Patient, Including Toxoplasmosis and Strongyloidiasis. Infect Dis Clin North Am 2019; 33:567-591. [PMID: 31005139 DOI: 10.1016/j.idc.2019.02.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hematopoietic stem cell transplantation (HSCT) recipients may infrequently develop parasitic infections at the time of the procedure via contamination from allograft tissue or blood products, and in the post-transplantation period through the traditional route of infection or as a reactivation caused by immunosuppression related to the transplant. To reduce risk, efforts should be directed at performing a comprehensive history, maintaining a high index of suspicion, and adhering to preventive measures. Additional strategies for the prevention, screening and careful follow-up, identification, and pre-emptive treatment of parasitic infections are required to reduce morbidity and mortality in HSCT patients.
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Affiliation(s)
- Driele Peixoto
- São Paulo State Cancer Institute (ICESP), Hospital das Clínicas, Av. Dr. Arnaldo, 251, São Paulo CEP: 01246-000, Brazil.
| | - Daniel P Prestes
- A. C. Camargo Cancer Center, Rua Professor Antonio Prudente, 211, Sao Paulo CEP: 01509-010, Brazil; Emilio Ribas Infectious Diseases Institute, Av. Doutor Arnaldo, 165, Sao Paulo CEP: 01246-900, Brazil
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Doshi N, Thet Z, Han T, Martin J. A Case of Intestinal Microsporidiosis in a Renal Transplant Recipient. J Med Cases 2019; 10:229-233. [PMID: 34434311 PMCID: PMC8383712 DOI: 10.14740/jmc3340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 07/30/2019] [Indexed: 12/20/2022] Open
Abstract
Post-renal transplant diarrhea is a common clinical presentation. An extensive list of potential etiology adds to the diagnostic dilemma. In cases of prolonged or intractable diarrhea, invasive tests are often performed. Intestinal microsporidia can be diagnosed with simple non-invasive stool polymerase chain reaction (PCR). Based on this case, we propose an easy to follow flow chart and present a literature review on post-renal transplant diarrhea. Further multicenter validation testing is required for the proposed flow chart.
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Affiliation(s)
- Nidhi Doshi
- Department of General Medicine, Gold Coast University Hospital, QLD, Australia
| | - Zaw Thet
- Department of Nephrology, Central Queensland Hospital and Health Service, Rockhampton, QLD, Australia
| | - Thin Han
- Department of Nephrology, Central Queensland Hospital and Health Service, Rockhampton, QLD, Australia.,Rural Clinical School, University of Queensland, Rockhampton, QLD, Australia
| | - Julieanne Martin
- Department of Nephrology, Central Queensland Hospital and Health Service, Rockhampton, QLD, Australia
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Kicia M, Szydłowicz M, Cebulski K, Jakuszko K, Piesiak P, Kowal A, Sak B, Krajewska M, Hendrich AB, Kváč M, Kopacz Ż. Symptomatic respiratory Encephalitozoon cuniculi infection in renal transplant recipients. Int J Infect Dis 2018; 79:21-25. [PMID: 30391325 DOI: 10.1016/j.ijid.2018.10.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/25/2018] [Accepted: 10/21/2018] [Indexed: 11/29/2022] Open
Abstract
OBJECTIVES Encephalitozoon spp. and Enterocytozoon bieneusi are intracellular parasitic fungi from the phylum Microsporidia, which initially localize to the intestine. As opportunistic pathogens, Encephalitozoon spp. in particular can disseminate to the respiratory tract, among other locations. Patients on life-long immunosuppression are at higher risk of such infections, mostly symptomatic. METHODS Sputum samples and bronchial washings from 72 renal transplant recipients and 105 patients with various respiratory diseases were screened for Encephalitozoon spp. and E. bieneusi by microscopic examination and genus-specific nested PCR followed by genotyping. RESULTS A total of 8.3% (6/72) of immunosuppressed renal transplant recipients and 1.9% (2/105) of patients with various respiratory diseases, both immunocompetent and immunosuppressed, were positive for respiratory microsporidial infection. All six transplant recipients were Encephalitozoon cuniculi-positive by PCR/sequencing and five of them suffered from respiratory symptoms. The presence of microsporidial spores was also confirmed microscopically in three of the transplant recipients. Of the two immunocompetent patients with various respiratory diseases, one had an E. cuniculi infection, while the second had an E. bieneusi infection. CONCLUSIONS Life-long immunosuppression in renal transplant recipients increases the risk of respiratory infection by E. cuniculi. Microsporidia should be screened in respiratory samples of these patients, particularly when they have respiratory symptoms.
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Affiliation(s)
- Marta Kicia
- Department of Biology and Medical Parasitology, Wroclaw Medical University, J. Mikulicza-Radeckiego 9, 50-367 Wroclaw, Poland.
| | - Magdalena Szydłowicz
- Department of Biology and Medical Parasitology, Wroclaw Medical University, J. Mikulicza-Radeckiego 9, 50-367 Wroclaw, Poland
| | - Kamil Cebulski
- Department of Biology and Medical Parasitology, Wroclaw Medical University, J. Mikulicza-Radeckiego 9, 50-367 Wroclaw, Poland
| | - Katarzyna Jakuszko
- Department of Nephrology and Transplantation Medicine, Borowska 213, 50-556 Wroclaw Medical University, Wroclaw, Poland
| | - Paweł Piesiak
- Department of Pulmonology and Lung Cancer, Wroclaw Medical University, Grabiszyńska 105, 53-439 Wroclaw, Poland
| | - Aneta Kowal
- Department of Pulmonology and Lung Cancer, Wroclaw Medical University, Grabiszyńska 105, 53-439 Wroclaw, Poland
| | - Bohumil Sak
- Czech Academy of Sciences, Biology Centre, Institute of Parasitology, Branišovská 31, CZ-370 05 České Budějovice, Czech Republic
| | - Magdalena Krajewska
- Department of Nephrology and Transplantation Medicine, Borowska 213, 50-556 Wroclaw Medical University, Wroclaw, Poland
| | - Andrzej B Hendrich
- Department of Biology and Medical Parasitology, Wroclaw Medical University, J. Mikulicza-Radeckiego 9, 50-367 Wroclaw, Poland
| | - Martin Kváč
- Czech Academy of Sciences, Biology Centre, Institute of Parasitology, Branišovská 31, CZ-370 05 České Budějovice, Czech Republic; University of South Bohemia, Faculty of Agriculture, Branišovská 31, CZ-370 05 České Budějovice, Czech Republic
| | - Żaneta Kopacz
- Department of Biology and Medical Parasitology, Wroclaw Medical University, J. Mikulicza-Radeckiego 9, 50-367 Wroclaw, Poland
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Smith RM, Muehlenbachs A, Schaenmann J, Baxi S, Koo S, Blau D, Chin-Hong P, Thorner AR, Kuehnert MJ, Wheeler K, Liakos A, Jackson JW, Benedict T, da Silva AJ, Ritter JM, Rollin D, Metcalfe M, Goldsmith CS, Visvesvara GS, Basavaraju SV, Zaki S. Three Cases of Neurologic Syndrome Caused by Donor-Derived Microsporidiosis. Emerg Infect Dis 2018; 23:387-395. [PMID: 28220747 PMCID: PMC5382757 DOI: 10.3201/eid2303.161580] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Encephalitozoon cuniculi was transmitted from an infected donor to 3 solid organ recipients, 1 of whom died. In April 2014, a kidney transplant recipient in the United States experienced headache, diplopia, and confusion, followed by neurologic decline and death. An investigation to evaluate the possibility of donor-derived infection determined that 3 patients had received 4 organs (kidney, liver, heart/kidney) from the same donor. The liver recipient experienced tremor and gait instability; the heart/kidney and contralateral kidney recipients were hospitalized with encephalitis. None experienced gastrointestinal symptoms. Encephalitozoon cuniculi was detected by tissue PCR in the central nervous system of the deceased kidney recipient and in renal allograft tissue from both kidney recipients. Urine PCR was positive for E. cuniculi in the 2 surviving recipients. Donor serum was positive for E. cuniculi antibodies. E. cuniculi was transmitted to 3 recipients from 1 donor. This rare presentation of disseminated disease resulted in diagnostic delays. Clinicians should consider donor-derived microsporidial infection in organ recipients with unexplained encephalitis, even when gastrointestinal manifestations are absent.
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Garcia LS, Arrowood M, Kokoskin E, Paltridge GP, Pillai DR, Procop GW, Ryan N, Shimizu RY, Visvesvara G. Practical Guidance for Clinical Microbiology Laboratories: Laboratory Diagnosis of Parasites from the Gastrointestinal Tract. Clin Microbiol Rev 2018; 31:e00025-17. [PMID: 29142079 PMCID: PMC5740970 DOI: 10.1128/cmr.00025-17] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
This Practical Guidance for Clinical Microbiology document on the laboratory diagnosis of parasites from the gastrointestinal tract provides practical information for the recovery and identification of relevant human parasites. The document is based on a comprehensive literature review and expert consensus on relevant diagnostic methods. However, it does not include didactic information on human parasite life cycles, organism morphology, clinical disease, pathogenesis, treatment, or epidemiology and prevention. As greater emphasis is placed on neglected tropical diseases, it becomes highly probable that patients with gastrointestinal parasitic infections will become more widely recognized in areas where parasites are endemic and not endemic. Generally, these methods are nonautomated and require extensive bench experience for accurate performance and interpretation.
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Affiliation(s)
| | - Michael Arrowood
- Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases, Division of Foodborne, Waterborne, and Environmental Diseases, Waterborne Disease Prevention Branch, Atlanta, Georgia, USA
| | - Evelyne Kokoskin
- Public Health Ontario, Ottawa, Ontario, Canada
- Public Health Laboratories-Ottawa, Ottawa, Ontario, Canada
| | | | - Dylan R Pillai
- Calgary Laboratory Services, Diagnostic and Scientific Centre, Calgary, Alberta, Canada
| | - Gary W Procop
- Enterprise Test Utilization and Pathology Consultative Services, Cleveland, Ohio, USA
- Molecular Microbiology, Parasitology, and Mycology Laboratories, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, USA
| | - Norbert Ryan
- Bacteriology and Parasitology, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute, Melbourne, Victoria, Australia
| | | | - Govinda Visvesvara
- Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases, Division of Foodborne, Waterborne, and Environmental Diseases, Waterborne Disease Prevention Branch, Atlanta, Georgia, USA
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9
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Abstract
A review of pulmonary infections of all types with diagnostic and morphological features.
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10
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Fabiani S, Fortunato S, Petrini M, Bruschi F. Allogeneic hematopoietic stem cell transplant recipients and parasitic diseases: A review of the literature of clinical cases and perspectives to screen and follow-up active and latent chronic infections. Transpl Infect Dis 2017; 19. [PMID: 28128496 DOI: 10.1111/tid.12669] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 10/20/2016] [Accepted: 10/29/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Allogeneic hematopoietic stem cell transplant (HSCT) recipients are at substantial risk for a variety of infections depending upon numerous factors, such as degree of immunosuppression, host factors, and period after transplantation. Bacterial, fungal, viral, as well as parasitic infections can occur with high morbidity and mortality. OBJECTIVES The aim of this study was to evaluate the magnitude of the occurrence of parasitic infections in allogeneic HSCT recipients. Modalities of transmission, methods of diagnosis, treatment, donor and recipient pre-transplant screening and prevention measures of the most serious parasitic infections have also been discussed. MATERIALS AND METHODS We systematically reviewed literature records on post-transplant (allogeneic HSCT) parasitic infections, identified through PubMed database searching, using no language or time restrictions. Search was concluded on December 31, 2015. In the present review, we only discussed post-transplant parasitic infections in allogeneic HSCT. Only exclusion criteria were absence of sufficient information on the transmission of parasitic infection to the recipient. Autologous HSCT recipients have not been included because of the absence of a proper allogeneic transplantation even in presence of blood or blood product transfusions. The methods and findings of the present review have been reported based on the preferred reporting items for systematic reviews and meta-analysis checklist (PRISMA). RESULTS Regarding allogeneic HSCT recipients, from data published in the literature the real burden of parasitic infections cannot be really estimated. Nevertheless, a positive trend on publication number exists, probably because of more than one reason: (i) the increasing number of patients transplanted and then treated with immunosuppressive agents, (ii) the "population shift" resulting from immigration and travels to endemic areas, and (iii) the increasing of attention for diagnosis/notification/publication of cases. CONCLUSIONS Considering parasitic infections as emerging and potentially serious in their evolution, additional strategies for the prevention, careful screening and follow-up, with a high level of suspicion, identification, and preemptive therapy are necessary in transplant recipients. PERSPECTIVES The Authors' viewpoint in the perspective to screen and follow-up active and latent chronic parasitosis in stem cells donors and recipients: a proposal for a flow chart.
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Affiliation(s)
- Silvia Fabiani
- School of Infectious Diseases, Università di Pisa, Pisa, Italy
| | | | - Mario Petrini
- Department of Experimental and Clinical Medicine, Università di Pisa, Pisa, Italy.,Unit of Hematology, AOU Pisana, Pisa, Italy
| | - Fabrizio Bruschi
- School of Infectious Diseases, Università di Pisa, Pisa, Italy.,Department of Translational Research, N.T.M.S., Università di Pisa, Pisa, Italy
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Stentiford GD, Becnel JJ, Weiss LM, Keeling PJ, Didier ES, Williams BAP, Bjornson S, Kent ML, Freeman MA, Brown MJF, Troemel ER, Roesel K, Sokolova Y, Snowden KF, Solter L. Microsporidia - Emergent Pathogens in the Global Food Chain. Trends Parasitol 2016; 32:336-348. [PMID: 26796229 PMCID: PMC4818719 DOI: 10.1016/j.pt.2015.12.004] [Citation(s) in RCA: 176] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 11/26/2015] [Accepted: 12/07/2015] [Indexed: 02/07/2023]
Abstract
Intensification of food production has the potential to drive increased disease prevalence in food plants and animals. Microsporidia are diversely distributed, opportunistic, and density-dependent parasites infecting hosts from almost all known animal taxa. They are frequent in highly managed aquatic and terrestrial hosts, many of which are vulnerable to epizootics, and all of which are crucial for the stability of the animal-human food chain. Mass rearing and changes in global climate may exacerbate disease and more efficient transmission of parasites in stressed or immune-deficient hosts. Further, human microsporidiosis appears to be adventitious and primarily associated with an increasing community of immune-deficient individuals. Taken together, strong evidence exists for an increasing prevalence of microsporidiosis in animals and humans, and for sharing of pathogens across hosts and biomes.
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Affiliation(s)
- G D Stentiford
- Pathology and Molecular Systematics Team, Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Barrack Road, Weymouth, Dorset DT4 8UB, UK
| | - -J J Becnel
- United States Department of Agriculture (USDA) Agricultural Research Center (ARS), Center for Medical, Agricultural, and Veterinary Entomology (CMAVE), 1600 South West 23rd Drive, Gainesville, FL, 32608, USA
| | - L M Weiss
- Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer 504, Bronx, NY 10641, USA
| | - P J Keeling
- Canadian Institute for Advanced Research, Botany Department, University of British Columbia, 3529-6270 University Boulevard, Vancouver, BC, V6T 1Z4 Canada
| | - E S Didier
- Division of Microbiology, Tulane National Primate Research Center and Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, 1440 Canal Street, New Orleans, LA 70112, USA
| | - B-A P Williams
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope, Stocker Road, Exeter EX4 4QD, UK
| | - S Bjornson
- Department of Biology, Saint Mary's University, 923 Robie Street, Halifax, Nova Scotia, Canada
| | - M-L Kent
- Departments of Microbiology and Biomedical Sciences, 220 Nash Hall, Oregon State University, Corvallis, OR 97331, USA
| | - M A Freeman
- Ross University School of Veterinary Medicine, St. Kitts, West Indies
| | - M J F Brown
- School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK
| | - E-R Troemel
- University of California, San Diego, 4202 Bonner Hall, 9500 Gilman Drive #0349, La Jolla, CA 92093-0349, USA
| | - K Roesel
- International Livestock Research Institute, c/o Freie Universität Berlin, Institute of Parasitology and Tropical Veterinary Medicine, Robert-von-Ostertag-Strasse 7-13, Berlin, 14163 Germany
| | - Y Sokolova
- Department of Comparative Biomedical Sciences, Louisiana State University, School of Veterinary Medicine, 1909 Skip Bertman Drive, Baton RougeLA 70803, USA
| | - K F Snowden
- Texas A&M University, College of Veterinary Medicine and Biomedical Sciences, Department of Veterinary Pathobiology, Mailstop 4467, College Station, TX 77843-4467, USA
| | - L Solter
- Illinois Natural History Survey, Prairie Research Institute at the University of Illinois at Urbana-Champaign, 1816 South Oak Street, Champaign, IL 61820, USA.
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Nevez G, Le Gal S, Quinio D, Ianotto JC, Berthou C, Hamane S, Sarfati C, Menotti J. Encephalitozoon hellem in a patient with CD4+ T-cell prolymphocytic leukemia: case report and genomic identification. Diagn Microbiol Infect Dis 2015; 83:245-7. [DOI: 10.1016/j.diagmicrobio.2015.07.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 07/20/2015] [Indexed: 11/26/2022]
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Interleukin-12-producing CD103+ CD11b- CD8+ dendritic cells are responsible for eliciting gut intraepithelial lymphocyte response against Encephalitozoon cuniculi. Infect Immun 2015; 83:4719-30. [PMID: 26416905 DOI: 10.1128/iai.00820-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 09/17/2015] [Indexed: 12/23/2022] Open
Abstract
Microsporidia, which belong to the kingdom Fungi, are important opportunistic pathogens in HIV-infected populations and organ transplant recipients that are often associated with a broad range of symptoms, such as diarrhea, nephritis, and encephalitis. Natural infection occurs via the oral route, and as a consequence, gut immunity plays an important role in restricting the dissemination of these pathogens. Studies from our laboratory have reported that the pathogens induce a rapid intraepithelial lymphocyte (IEL) response important for host protection. Although mucosal dendritic cells (DC) are likely involved in triggering an antigen-specific IEL response, the specific subset(s) responsible has yet to be identified. Toward this goal, we demonstrate a very important role for mucosal CD11b(-) CD8(+) DC in the initiation of an antigen-specific IEL in vivo. Effectively, after Encephalitozoon cuniculi infection, CD11b(-) CD8(+) DC were activated in the lamina propria (LP) and acquired the ability to process retinoic acid (RA). However, this subset did not produce interleukin 12 (IL-12) but upregulated CD103, which is essential for migration to the mesenteric lymph nodes (MLN). Interestingly, CD103(+) CD11b(-) CD8(+) DC in the MLN, in addition to processing RA, also secreted IL-12 and were responsible for gut imprinting specificity on mucosal CD8 T cells. To the best of our knowledge, this is the first report describing the importance of MLN CD103(+) CD11b(-) CD8(+) DC isolated from infected animals in the generation of an IEL response against a live pathogen.
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Young JAH, Weisdorf DJ. Infections in Recipients of Hematopoietic Stem Cell Transplants. MANDELL, DOUGLAS, AND BENNETT'S PRINCIPLES AND PRACTICE OF INFECTIOUS DISEASES 2015. [PMCID: PMC7152282 DOI: 10.1016/b978-1-4557-4801-3.00312-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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15
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Wagnerová P, Sak B, Květoňová D, Maršálek M, Langrová I, Kváč M. Humoral immune response and spreading of Encephalitozoon cuniculi infection in experimentally infected ponies. Vet Parasitol 2013; 197:1-6. [PMID: 23747106 DOI: 10.1016/j.vetpar.2013.05.007] [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: 03/15/2013] [Revised: 04/18/2013] [Accepted: 05/07/2013] [Indexed: 11/25/2022]
Abstract
A total of 9 (8 stallions and 1 mare) 1 year old ponies were used for the experimental infection caused by Encephalitozoon cuniculi genotype II (10(7) spores per animal). Subsequently, individual horses were slaughtered 7, 14, 21, 28, 35, 42, 49, 56, and 63 days post infection. Immediately after slaughter, tissues samples of stomach, duodenum, jejunum, ileum, caecum, colon, spleen, liver, kidney, bladder, heart, lungs, and brain were sampled. In addition, urine, feces and blood specimens were collected. Enzyme-linked immunosorbent assay was used for determination of humoral immune response and nested PCR targeting 16S rDNA, whole ITS, and 5.8S rDNA was used for detection of E. cuniculi in collected organs, blood, feces and urine. No clinical signs of microsporidiosis including diarrhea or colic, neurological signs and fever were observed in any horses during whole experiment. Acute microsporidiosis in ponies was characterized by the dissemination of microsporidia into almost all organs and significant increase of concentration of specific antibodies in blood was observed from 28 to 42 DPI. After this acute stage microsporidia disappeared from most organs with the exception of the kidney, which was positive up to 63 DPI when the experiment was terminated. No pathological changes were observed in any organs with exception of one mare's brain, where E. cuniculi-positive cavity measuring 5 cm × 3 cm in diameter formed in the lobus piriformis.
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Affiliation(s)
- Pavla Wagnerová
- Faculty of Agriculture, University of South Bohemia in České Budějovice, Studentská 13, 370 05 České Budějovice, Czech Republic
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16
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Key Diagnostic Features of Granulomatous Interstitial Nephritis Due to Encephalitozoon cuniculi in a Lung Transplant Recipient. Am J Surg Pathol 2013; 37:447-52. [DOI: 10.1097/pas.0b013e31827e1968] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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17
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Meissner EG, Bennett JE, Qvarnstrom Y, da Silva A, Chu EY, Tsokos M, Gea-Banacloche J. Disseminated microsporidiosis in an immunosuppressed patient. Emerg Infect Dis 2012; 18:1155-8. [PMID: 22709509 PMCID: PMC3376806 DOI: 10.3201/eid1807.120047] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We report a case of disseminated microsporidiosis in a patient with multiple myeloma who had received an allogeneic stem cell transplant requiring substantial immunosuppression. The causative organism was identified as Tubulinosema acridophagus, confirming this genus of microsporidia as a novel human pathogen.
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Affiliation(s)
- Eric G Meissner
- National Institutes of Health, Bethesda, Maryland 20892, USA.
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18
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Field A, Paik J, Stark D, Qiu M, Morey A, Plit M, Canning E, Glanville A. Myositis due to the microsporidianAnncaliia (Brachiola) algeraein a lung transplant recipient. Transpl Infect Dis 2012; 14:169-76. [DOI: 10.1111/j.1399-3062.2012.00724.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 01/12/2012] [Accepted: 01/16/2012] [Indexed: 11/30/2022]
Affiliation(s)
- A.S. Field
- Division of Anatomical Pathology; St Vincent's Hospital; Sydney NSW Australia
| | - J.Y. Paik
- Division of Anatomical Pathology; St Vincent's Hospital; Sydney NSW Australia
| | - D. Stark
- Division of Microbiology; St Vincent's Hospital; Sydney NSW Australia
| | - M.R. Qiu
- Division of Anatomical Pathology; St Vincent's Hospital; Sydney NSW Australia
| | - A. Morey
- Division of Anatomical Pathology; St Vincent's Hospital; Sydney NSW Australia
| | - M.L. Plit
- Department of Thoracic Medicine; St Vincent's Hospital; Sydney NSW Australia
| | | | - A.R. Glanville
- Department of Thoracic Medicine; St Vincent's Hospital; Sydney NSW Australia
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19
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Lobo ML, Xiao L, Antunes F, Matos O. Microsporidia as emerging pathogens and the implication for public health: a 10-year study on HIV-positive and -negative patients. Int J Parasitol 2012; 42:197-205. [PMID: 22265899 DOI: 10.1016/j.ijpara.2011.12.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 12/02/2011] [Accepted: 12/08/2011] [Indexed: 11/29/2022]
Abstract
Despite recent advances in the understanding and diagnosis of emerging microsporidian pathogens, more research is necessary to elucidate their complex epidemiology. In fact, studies that reflect true human-infecting microsporidian prevalence are still inadequate. The present 10-year study was undertaken to examine the occurrence of Microsporidia in 1989 stools, 69 urine and 200 pulmonary specimens from HIV-positive and HIV-negative patients using PCR and DNA sequencing. In stools, 12.0% were Microsporidia-positive. Prevalences of 13.9% and 8.5% were observed for HIV+ and HIV- samples, respectively. The percentage of children that were Microsporidia-positive (18.8%) was significantly higher than that of adults (10.2%). In stools, Enterocytozoon bieneusi (6.3%) and Vittaforma-like parasites (6.8%) were identified. Based on the internal transcribed spacer (ITS) region of E. bieneusi, Type IV (37.5%), Peru 6 (29.2%), D (12.5%), A (8.3%), C (6.3%) and PtEb II (6.3%) genotypes were identified. Microsporidia were detected in 1.5% and 1.0% of urine and pulmonary specimens, respectively. Encephalitozoonintestinalis was detected in urine. In pulmonary specimens, Encephalitozoon cuniculi and Vittaforma-like parasites were identified. An immunosuppressive condition and youth (children) appear to be risk factors for microsporidian infection. Microsporidia seems to have an important impact on public health in Portugal, highlighting the need to implement routine diagnosis.
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Affiliation(s)
- Maria Luísa Lobo
- Grupo de Protozoários Oportunistas/VIH e Outras Protozooses/Unidade de Parasitologia Médica, CMDT, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
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Microsporidia infection in a mexican kidney transplant recipient. Case Rep Nephrol 2012; 2012:928083. [PMID: 24558617 PMCID: PMC3914178 DOI: 10.1155/2012/928083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 11/29/2012] [Indexed: 11/17/2022] Open
Abstract
Microorganisms of the microsporidia group are obligated intracellular protozoa that belong to the phylum Microspora; currently they are considered to be related or belong to the fungi reign. It is considered an opportunistic infection in humans, and 14 species belonging to 8 different genera have been described. Immunocompromized patients such as those infected with human immunodeficiency virus (HIV), also HIV serum-negative asymptomatic patients, with poor hygienic conditions, and recipients of bone marrow or solid organ transplantation are susceptible to develop deinfection. Sixty transplanted patients with renal microsporidia infection have been reported worldwide. The aim of this paper is to inform about the 2nd case of kidney transplant and microsporidia infection documented in Mexico.
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Encephalitozoon cuniculi genotype I as a causative agent of brain abscess in an immunocompetent patient. J Clin Microbiol 2011; 49:2769-71. [PMID: 21593268 DOI: 10.1128/jcm.00620-11] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A brain abscess caused by Encephalitozoon cuniculi genotype I together with Streptococcus intermedius occurred in a patient without major immunocompromise and with diabetes. The distinguishing clinical signs were hemiparesis and epilepsy. The microsporidium was observed in the abscess aspirate, and its specific DNA was also detected in stool and urine. The patient was successfully treated with albendazole and mebendazole.
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First cases of microsporidiosis in transplant recipients in Spain and review of the literature. J Clin Microbiol 2011; 49:1301-6. [PMID: 21325545 DOI: 10.1128/jcm.01833-10] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsporidia are currently considered emerging pathogens responsible for life-threatening infections in organ transplant recipients. Here, we describe the first cases of intestinal microsporidiosis by Enterocytozoon bieneusi genotype D in two non-HIV-infected renal transplant recipients from Spain. Previously reported cases of microsporidiosis in organ transplant recipients have also been reviewed, highlighting the necessity of considering organ transplant recipients a risk group for microsporidiosis. A systematic search for these parasites is recommended in cases of persistent diarrhea and in the differential diagnosis of other syndromes, such as chronic fever of unknown etiology.
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Diagnosis of intestinal microsporidiosis in pediatric oncology patients in Egypt using modified acid fast trichrome staining versus PCR. Acta Parasitol 2011. [DOI: 10.2478/s11686-011-0072-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
AbstractMicrosporidia are intracellular opportunistic parasites that cause chronic diarrhea in AIDS patients. Little is known about the prevalence of these pathogens in pediatric cases with cancer and diarrhea. Unidentified causes of chronic diarrhea were previously encountered in pediatric cancer patients at the National Cancer Institute in Egypt. Therefore, this study tried to search for the contribution of microsporidia as a causative agent of diarrhea in this population using acid-fast trichrome stain as a specific staining and the PCR in order to evaluate the staining technique in clinical diagnosis of microsporidia. Between January 2008 and June 2009, 271 diarrheic samples from pediatric patients with cancer were studied. Microsporidia were confirmed in 13 (4.8%) cases by both PCR and staining, and additional 2 samples were positive only by staining. As a negative control, stool samples from 60 diarrheic children without malignant cancer and no microsporidia detection were examined by these two methods. So, it can be concluded that adding a diagnostic test for microsporidia to the clinical laboratory work in hospitals concerned with cancer is essential. Acid fast trichrome staining technique as being nearly efficacious as the PCR, but simpler and less expensive, can replace the molecular techniques for the diagnosis of microsporidia.
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Abstract
Food- and water-borne infections have afflicted mankind since the earliest days of human development and preceded the emergence of civilization. Despite current knowledge of microbial pathogenicity, modern methods of food production and rigorous industrial hygiene, these infections are still commonplace and exact significant health and economic tolls on human populations in all parts of the globe. This review uses data derived from new surveillance networks to survey the current epidemiology of bacterial, protozoan and viral pathogens transmitted by food and water. In addition, we will discuss clinical features of human disease caused by pathogens of current and emerging relevance.
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Abstract
Parasitic infections are an uncommon but potentially severe complication in solid organ transplant (SOT) recipients. An increase in donors who have emigrated from tropical areas and more transplant recipients traveling to endemic areas have led to a rise in parasitic infections reported among SOT recipients. Clinicians should include these infections in their differential diagnosis and promote adherence to preventive measures in SOT recipients.
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Disseminated infection with a new genovar of Encephalitozoon cuniculi in a renal transplant recipient. J Clin Microbiol 2010; 48:2651-3. [PMID: 20463169 DOI: 10.1128/jcm.02539-09] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Disseminated microsporidiosis is a life-threatening opportunistic infection. Here, we report about a previously undescribed genovar of Encephalitozoon cuniculi causing disseminated infection in a non-HIV-infected renal transplant recipient. Disseminated microsporidiosis must be considered in the differential diagnosis of chronic fever in renal allograft recipients, even those without urinary symptoms.
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Transplantation and tropical infectious diseases. Int J Infect Dis 2009; 14:e189-96. [PMID: 19647464 DOI: 10.1016/j.ijid.2009.04.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 04/03/2009] [Accepted: 04/14/2009] [Indexed: 02/08/2023] Open
Abstract
The number of transplant recipients with tropical infectious diseases is growing due to increasing international travel and the rising number of transplants taking place in the tropics and subtropics. With increases in population migration, the prevalence of individuals infected with geographically restricted organisms also rises. There are three potential categories of tropical infections in transplant patients: (1) donor-related infections transmitted by the graft or through transfusion of blood products; (2) reactivation or recrudescence of latent infections in the donor recipient; and (3) de novo acquisition of infection in the post-transplant period through the traditional route of infection. We present an overall discussion of the association of parasitic (protozoa and helminths) and non-parasitic (viral, bacterial, and fungal) tropical infectious diseases and solid-organ and hematopoietic transplantation. We also suggest potential screening guidelines for some of these tropical infections.
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Lindsay DS, Goodwin DG, Zajac AM, Cortés-Vecino JA, Gennari SM, Rosypal AC, Dubey JP. Serological Survey for Antibodies to Encephalitozoon cuniculi in Ownerless Dogs From Urban Areas of Brazil and Colombia. J Parasitol 2009; 95:760-3. [DOI: 10.1645/ge-1890.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Accepted: 10/16/2008] [Indexed: 11/10/2022] Open
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29
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Jamet D, Quinio D, Moalic E, Ianotto JC, Dalbies F, Guillerm G, Marion V, Berthou C, Nevez G. Microsporidiose et toxoplasmose disséminées chez une patiente présentant une leucémie prolymphocytaire T. Med Mal Infect 2009; 39:406-8. [DOI: 10.1016/j.medmal.2008.10.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 08/08/2008] [Accepted: 10/15/2008] [Indexed: 10/21/2022]
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Lono AR, Kumar S, Chye TT. Incidence of Microsporidia in Cancer Patients. J Gastrointest Cancer 2009; 39:124-9. [DOI: 10.1007/s12029-009-9065-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Accepted: 04/15/2009] [Indexed: 10/20/2022]
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Lanternier F, Boutboul D, Menotti J, Chandesris MO, Sarfati C, Mamzer Bruneel MF, Calmus Y, Mechaï F, Viard JP, Lecuit M, Bougnoux ME, Lortholary O. Microsporidiosis in solid organ transplant recipients: two Enterocytozoon bieneusi cases and review. Transpl Infect Dis 2008; 11:83-8. [PMID: 18803616 DOI: 10.1111/j.1399-3062.2008.00347.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Microsporidiosis first came to prominence as an opportunistic infection in patients with acquired immunodeficiency syndrome. Microsporidia are now emerging pathogens responsible for severe diarrhea during solid organ transplantation. Two main clinical entities can be identified: infection by Enterocytozoon bieneusi, causing diarrhea with limited treatment options; and infection by Encephalitozoon intestinalis, which may disseminate and usually responds to albendazole treatment. We describe here 2 cases of microsporidiosis caused by E. bieneusi in a renal and a liver transplant recipient, respectively, in whom complete clinical efficacy of a short course of fumagillin therapy was obtained. Long-term microbiological eradication was assessed using classical methods and monitored using a real-time quantitative polymerase chain reaction-based method. Both patients experienced drug-induced thrombocytopenia, which resolved after withdrawal of the treatment. We also review the 18 other previously reported cases of microsporidiosis in transplant recipients. In case of persistent diarrhea in solid organ transplant patients, microsporidiosis should be considered. Based on the present experience, treating E. bieneusi infection with 7 days of fumagillin therapy is adequate to eradicate E. bieneusi in this context.
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Affiliation(s)
- F Lanternier
- Centre d'Infectiologie Necker-Pasteur, Service des Maladies Infectieuses et Tropicales, Hôpital Necker-Enfants malades, Université Paris Descartes, Paris, France
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Johny S, Whitman DW. Effect of four antimicrobials against an Encephalitozoon sp. (Microsporidia) in a grasshopper host. Parasitol Int 2008; 57:362-7. [PMID: 18495525 DOI: 10.1016/j.parint.2008.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 03/13/2008] [Accepted: 03/20/2008] [Indexed: 11/15/2022]
Abstract
Encephalitozoon spp. are the primary microsporidial pathogens of humans and domesticated animals. In this experiment, we test the efficacy of 4 commercial antimicrobials against an Encephalitozoon sp. infecting a grasshopper (Romalea microptera) host. Oral treatment with fumagillin or thiabendazole significantly reduced pathogen spore counts (93% and 88% respectively), whereas spore counts of grasshoppers fed quinine produced a non-significant 53% reduction in spores, and those fed streptomycin a non-significant 29% increase in spores, compared to the control. We observed a moderate dose-response effect for thiabendazole, whereby spore count decreased as drug consumption increased. No thiabendazole-treated animals died, whereas 27% of streptomycin-treated animals died, suggesting that thiabendazole was not toxic at the doses administered. The deaths among streptomycin-treated animals may have been caused by drug toxicity, parasite burden, or both. Although fumagillin and thiabendazole significantly reduced spore counts, in no individual was the pathogen totally eliminated. Our data confirm that microsporidia are difficult to control and that fumagillin and thiabendazole are partially effective antimicrobials against this group. Our study suggests that quinine and related alkaloids should be further examined for antimicrosporidial activity, and streptomycin should be examined as a possible enhancer of microsporidiosis.
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Affiliation(s)
- Shajahan Johny
- Department of Biological Sciences, Illinois State University, Normal, Illinois 61790-4120, USA
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Barsoum RS. Parasitic infections in transplant recipients. ACTA ACUST UNITED AC 2006; 2:490-503. [PMID: 16941042 DOI: 10.1038/ncpneph0255] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 04/12/2006] [Indexed: 01/20/2023]
Abstract
Parasitic infections are important complications of organ transplantation that are often overlooked in the differential diagnosis of post-transplantation pyrexial illness. Although their frequency is unknown, they seem to be much less prevalent than bacterial and viral infections. Only 5% of human pathogenic parasites have been reported to cause significant illness in transplant recipients. Infection can occur via transmission with the graft or blood transfusion, or be acquired de novo from the environment. Recrudescence of dormant infection can lead to active disease. Post-transplantation parasitic disorders tend to cluster into two clinical profiles. First, an acute systemic illness with anemia, constitutional manifestations and variable stigmata of organ involvement; acute graft dysfunction can lead to confusion and acute rejection. Protozoa including malarial Plasmodium, Leishmania, Trypanosoma and Toxoplasma are associated with this profile. The second typical manifestation encompasses a few localized syndromes, usually associated with the lower gastrointestinal tract, caused by either protozoa (Cryptosporidium and microsporidia) or nematodes (Strongyloides and Ascaris). Dissemination of localized infections can lead to life-threatening systemic manifestations. A high index of suspicion is essential, as diagnosis requires special sampling techniques and laboratory procedures. Definitive diagnosis is usually achieved by detecting the parasite in the patient's tissues or body fluids by histological examination or culture, or by polymerase chain reaction amplification of the parasite-specific antigen sequence. Antibody detection using serological techniques is also possible in a few parasitic infections. Certain lesions have characteristic radiological appearances, hence the value of imaging, particularly in the cerebral syndromes. Treatment is usually straightforward (broad spectrum or specific drugs), yet some species are drug resistant.
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Abstract
PURPOSE OF REVIEW Microsporidiosis is an emerging and opportunistic infection associated with a wide range of clinical syndromes in humans. This review highlights the research on microsporidiosis in humans during the previous 2 years. RECENT FINDINGS The reduced and compact microsporidian genome has generated much interest for better understanding the evolution of these parasites, and comparative molecular phylogenetic studies continue to support a relationship between the microsporidia and fungi. Through increased awareness and improved diagnostics, microsporidiosis has been identified in a broader range of human populations that, in addition to persons with HIV infection, includes travelers, children, organ transplant recipients, and the elderly. SUMMARY Effective commercial therapies for Enterocytozoon bieneusi, the most common microsporidian species identified in humans, are still lacking, making the need to develop tissue culture and small animal models increasingly urgent. Environmental transport modeling and disinfection strategies are being addressed for improving water safety. Questions still exist about whether microsporidia infections remain persistent in asymptomatic immune-competent individuals, reactivate during conditions of immune compromise, or may be transmitted to others at risk, such as during pregnancy or through organ donation. Reliable serological diagnostic methods are needed to supplement polymerase chain reaction or histochemistry when spore shedding may be sporadic.
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Affiliation(s)
- Elizabeth S Didier
- Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana 70433, USA.
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Abstract
PURPOSE OF REVIEW In many cases, the specific pathogen responsible for a respiratory infection is not identified and can lead to improper medical treatment, increased duration of illness, and possibly contributes to the development of antibiotic resistance. Molecular-based diagnostic methodologies have significantly improved our ability to identify common respiratory pathogens; these techniques are not useful, however, when a novel pathogen is responsible for the infection and clinicians must rely on differential diagnosis for the treatment of patients. RECENT FINDINGS New pathogens previously not associated with human infections have been identified in the past few years. In addition, new strains of bacteria and viruses have emerged as the causative agents of pneumonia and acute respiratory distress. Protozoans and saprophytic fungi, which are not normally associated with respiratory infection, have also emerged as respiratory pathogens particularly in individuals with AIDS or in those who are otherwise immunocompromised. SUMMARY This review discusses the recent literature on newly described respiratory pathogens as well as opportunistic pathogens that can infect the respiratory system of immunocompromised individuals. The studies referenced here reveal the need for expanded laboratory tests and highly trained microbiologists in clinical laboratories worldwide.
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Affiliation(s)
- John A Lednicky
- Life Sciences Division, Midwest Research Institute, Kansas City, Missouri, USA.
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