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de Korne CM, van Lieshout L, van Leeuwen FWB, Roestenberg M. Imaging as a (pre)clinical tool in parasitology. Trends Parasitol 2023; 39:212-226. [PMID: 36641293 DOI: 10.1016/j.pt.2022.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/23/2022] [Accepted: 12/23/2022] [Indexed: 01/13/2023]
Abstract
Imaging of parasites is central to diagnosis of many parasitic diseases and has thus far played an important role in the development of antiparasitic strategies. The development of novel imaging technologies has revolutionized medicine in fields other than parasitology and has also opened up new avenues for the visualization of parasites. Here we review the role imaging technology has played so far in parasitology and how it may spur further advancement. We point out possibilities to improve current microscopy-based diagnostic methods and how to extend them with radiological imaging modalities. We also highlight in vivo tracking of parasites as a readout for efficacy of new antiparasitic strategies and as a source of fundamental insights for rational design.
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Affiliation(s)
- Clarize Maria de Korne
- Leiden University Center for Infectious Diseases, Leiden University Medical Centre, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands; Interventional Molecular Imaging laboratory, Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Lisette van Lieshout
- Leiden University Center for Infectious Diseases, Leiden University Medical Centre, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Fijs Willem Bernhard van Leeuwen
- Interventional Molecular Imaging laboratory, Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Meta Roestenberg
- Leiden University Center for Infectious Diseases, Leiden University Medical Centre, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands.
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O'Leary JK, Sleator RD, Lucey B. Cryptosporidium spp. diagnosis and research in the 21 st century. Food Waterborne Parasitol 2021; 24:e00131. [PMID: 34471706 PMCID: PMC8390533 DOI: 10.1016/j.fawpar.2021.e00131] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/06/2021] [Accepted: 08/17/2021] [Indexed: 01/01/2023] Open
Abstract
The protozoan parasite Cryptosporidium has emerged as a leading cause of diarrhoeal illness worldwide, posing a significant threat to young children and immunocompromised patients. While endemic in the vast majority of developing countries, Cryptosporidium also has the potential to cause waterborne epidemics and large scale outbreaks in both developing and developed nations. Anthroponontic and zoonotic transmission routes are well defined, with the ingestion of faecally contaminated food and water supplies a common source of infection. Microscopy, the current diagnostic mainstay, is considered by many to be suboptimal. This has prompted a shift towards alternative diagnostic techniques in the advent of the molecular era. Molecular methods, particularly PCR, are gaining traction in a diagnostic capacity over microscopy in the diagnosis of cryptosporidiosis, given the laborious and often tedious nature of the latter. Until now, developments in the field of Cryptosporidium detection and research have been somewhat hampered by the intractable nature of this parasite. However, recent advances in the field have taken the tentative first steps towards bringing Cryptosporidium research into the 21st century. Herein, we provide a review of these advances.
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Affiliation(s)
- Jennifer K. O'Leary
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland
| | - Roy D. Sleator
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland
| | - Brigid Lucey
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland
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Johansen ØH, Abdissa A, Zangenberg M, Mekonnen Z, Eshetu B, Bjørang O, Alemu Y, Sharew B, Langeland N, Robertson LJ, Hanevik K. Performance and operational feasibility of two diagnostic tests for cryptosporidiosis in children (CRYPTO-POC): a clinical, prospective, diagnostic accuracy study. THE LANCET. INFECTIOUS DISEASES 2020; 21:722-730. [PMID: 33278916 PMCID: PMC8064915 DOI: 10.1016/s1473-3099(20)30556-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/27/2020] [Accepted: 06/19/2020] [Indexed: 12/11/2022]
Abstract
Background Cryptosporidiosis is a common cause of diarrhoea in young children (aged younger than 24 months) in low-resource settings but is currently challenging to diagnose. Light-emitting diode fluorescence microscopy with auramine-phenol staining (LED-AP), recommended for tuberculosis testing, can also detect Cryptosporidium species. A lateral-flow test not requiring refrigerator storage (by contrast with most immunochromatographic lateral-flow assays) has also recently been developed for Cryptosporidium spp detection. We aimed to evaluate the diagnostic accuracy and operational feasibility of LED-AP and the lateral-flow test strip for cryptosporidiosis in children. Methods We did a prospective diagnostic accuracy study in two health-care facilities in Ethiopia, in a consecutive series of children younger than 5 years of age with diarrhoea (three or more loose stools within the previous 24 h) or dysentery (at least one loose stool with stains of blood within the previous 24 h). Stool samples were tested for Cryptosporidium spp by LED-AP and the lateral-flow test strip; accuracy of each test was estimated by independent and blind comparison with a composite reference standard comprising quantitative immunofluorescent antibody test (qIFAT), ELISA, and quantitative PCR (qPCR). Quantitative cutoff values for diarrhoea-associated infection were established in an embedded case-control substudy, with cases of cryptosporidiosis coming from the 15 districts in and around Jimma and the eight districts surrounding Serbo, and community controls without diarrhoea in the previous 48 h recruited by weekly frequency matching by geographical district of the household, age group, and enrolment week. Findings Stool samples from 912 children with diarrhoea or dysentery and 706 controls from the case-control substudy were tested between Dec 22, 2016, and July 6, 2018. Estimated reference-standard cutoff values for cryptosporidiosis positivity were 2·3 × 105 DNA copies per g of wet stool for qPCR, and 725 oocysts per g for qIFAT. LED-AP had a sensitivity for cryptosporidiosis of 88% (95% CI 79–94; 66 of 75 samples) and a specificity of 99% (98–99; 717 of 726 samples); the lateral-flow test strip had a sensitivity of 89% (79–94; 63 of 71 samples) and a specificity of 99% (97–99; 626 of 635 samples). Interpretation LED-AP has high sensitivity and specificity for cryptosporidiosis and should be considered as a dual-use technology that can be easily integrated with existing laboratory infrastructures in low-resource settings. The lateral-flow test strip has similar sensitivity and specificity and provides an alternative that does not require microscopy, although purchase cost of the test strip is unknown as it is not yet available on the market. Funding Norwegian Research Council GLOBVAC fund, The Bill & Melinda Gates Foundation, Norwegian Society for Medical Microbiology, University of Bergen, and Vestfold Hospital Trust.
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Affiliation(s)
- Øystein H Johansen
- Department of Clinical Science, University of Bergen, Bergen, Norway; Department of Microbiology, Vestfold Hospital Trust, Tønsberg, Norway.
| | - Alemseged Abdissa
- School of Medical Laboratory Sciences, Jimma University, Jimma, Ethiopia
| | - Mike Zangenberg
- Department of Immunology and Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark; Department of Clinical Microbiology, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Zeleke Mekonnen
- School of Medical Laboratory Sciences, Jimma University, Jimma, Ethiopia
| | - Beza Eshetu
- Department of Paediatrics and Child Health, Jimma Institute of Health, Jimma University, Jimma, Ethiopia
| | - Ola Bjørang
- Department of Microbiology, Vestfold Hospital Trust, Tønsberg, Norway
| | - Yonas Alemu
- School of Medical Laboratory Sciences, Jimma University, Jimma, Ethiopia
| | - Bizuwarek Sharew
- School of Medical Laboratory Sciences, Jimma University, Jimma, Ethiopia
| | - Nina Langeland
- Department of Clinical Science, University of Bergen, Bergen, Norway; Norwegian National Advisory Unit on Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Lucy J Robertson
- Parasitology, Department of Paraclinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Kurt Hanevik
- Department of Clinical Science, University of Bergen, Bergen, Norway; Norwegian National Advisory Unit on Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital, Bergen, Norway
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Masangkay FR, Milanez GD, Tsiami A, Hapan FZ, Somsak V, Kotepui M, Tangpong J, Karanis P. Waterborne protozoan pathogens in environmental aquatic biofilms: Implications for water quality assessment strategies. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 259:113903. [PMID: 32023789 DOI: 10.1016/j.envpol.2019.113903] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/29/2019] [Accepted: 12/29/2019] [Indexed: 06/10/2023]
Abstract
Biofilms containing pathogenic organisms from the water supply are a potential source of protozoan parasite outbreaks and a significant public health concern. The aim of the present study was to demonstrate the simultaneous and multi-spatial occurrence of waterborne protozoan pathogens (WBPP) in substrate-associated biofilms (SAB) and compare it to surface water (SW) and sediments with bottom water (BW) counterparts using manual filtration and elution from low-volume samples. For scenario purposes, simulated environmental biofilm contamination was created from in-situ grown one-month-old SAB (OM-SAB) that were spiked with Cryptosporidium parvum oocysts. Samples were collected from the largest freshwater reservoirs in Luzon, Philippines and a University Lake in Thailand. A total of 69 samples (23 SAB, 23 SW, and 23 BW) were evaluated using traditional staining techniques for Cryptosporidium, and Immunofluorescence staining for the simultaneous detection of Cryptosporidium and Giardia. WBPP were found in 43% SAB, 39% SW, and 39% BW of the samples tested in the present study with SAB results reflecting SW and BW results. Further highlights were demonstrated in the potential of using low-volume samples for the detection of parasites in source water. Scanning electron microscopy of OM-SAB samples revealed a naturally-associated testate amoeba shell, while Cryptosporidium oocysts spiked samples provided a visual profile of what can be expected from naturally contaminated biofilms. This study provides the first evidence for the simultaneous and multi-spatial occurrence of waterborne protozoan pathogens in low-volume aquatic matrices and further warrants SAB testing along with SW and BW matrices for improved water quality assessment strategies (iWQAS).
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Affiliation(s)
- Frederick R Masangkay
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand; Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University Manila, 1015, Philippines.
| | - Giovanni D Milanez
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand; Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University Manila, 1015, Philippines.
| | - Amalia Tsiami
- London Geller College of Hospitality and Tourism, University of West London, St Mary's Road, Ealing, London, W5 5RF, United Kingdom.
| | - Freida Z Hapan
- Department of Medical Technology, College of Pharmacy, The Pontifical and Royal University of Santo Tomas, España Blvd, Sampaloc, Manila, 1008, Philippines.
| | - Voravuth Somsak
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
| | - Manas Kotepui
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
| | - Jitbanjong Tangpong
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
| | - Panagiotis Karanis
- Medical Faculty and University Hospital of Cologne, Cologne, 50923, Germany; University of Nicosia Medical School, Nicosia, 2408, Cyprus.
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Hanscheid T, Vieira S, Ferreira P, Carvalho T, Belo S, Grobusch MP. The fluorescent acid-fast stain, auramine-O, stains schistosome eggs and may be an aid for detection. An old technique with a useful future? Travel Med Infect Dis 2020; 35:101569. [PMID: 32006658 DOI: 10.1016/j.tmaid.2020.101569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 01/28/2020] [Indexed: 10/25/2022]
Affiliation(s)
- Thomas Hanscheid
- Instituto de Microbiologia, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
| | - Soraia Vieira
- Instituto de Microbiologia, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Pedro Ferreira
- Medical Parasitology Unit, Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Tânia Carvalho
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Silvana Belo
- Medical Parasitology Unit, Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Martin P Grobusch
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Centers, location AMC, University of Amsterdam, Amsterdam, the Netherlands
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Abstract
Stained microscopy of fecal smears was the cornerstone of Cryptosporidium diagnosis for many years, and still provides a low-cost method for detecting oocysts. The development and commercialization of improved enzyme immunosorbent assays (EIA) for coproantigen detection provided an automatable method for mass testing, and rapid diagnostics when incorporated onto a cartridge format. Similarly, immunochromatographic lateral flow assays (ICLF) enable rapid diagnostics. Nevertheless, it is important that positive reactions by EIA or ICLF are confirmed. Here we describe microscopical methods using tinctorial stains for the diagnosis of acute cryptosporidiosis, and using immunofluorescent reagents for diagnosis or for confirmation of EIA or ICLF positive reactions.
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Affiliation(s)
- Guy Robinson
- Cryptosporidium Reference Unit, Public Health Wales Microbiology and Health Protection, Singleton Hospital, Swansea, UK
| | - Rachel M Chalmers
- Cryptosporidium Reference Unit, Public Health Wales Microbiology and Health Protection, Singleton Hospital, Swansea, UK.
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Joachim A, Ruttkowski B, Sperling D. Detection of Cystoisospora suis in faeces of suckling piglets - when and how? A comparison of methods. Porcine Health Manag 2018; 4:20. [PMID: 30250747 PMCID: PMC6145109 DOI: 10.1186/s40813-018-0097-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 06/26/2018] [Indexed: 12/30/2022] Open
Abstract
Background Cystoisospora suis is the causative agent of porcine neonatal coccidiosis, a diarrheal disease which affects suckling piglets in the first weeks of life. Detection of oocysts in the faeces of infected animals is frequently hampered by the short individual excretion period and the high fat content of faecal samples. We analysed oocyst excretion patterns of infected piglets, evaluated different detection methods for their detection limit and reproducibility, and propose a sampling scheme to improve the diagnosis of C. suis in faecal samples from the field using a protocol for reliable parasite detection. Results Based on a hypothesized model of the course of infection on a farm, three samplings (days of life 7–14-21 or 10–15-20) should be conducted including individual samples of piglets from each sampled litter. Samples can be examined by a modified McMaster method (lower detection limit: 333 oocysts per gram of faeces, OpG), by examining faecal smears under autofluorescence (lower detection limit: 10 OpG) or after carbol-fuchsin staining (lower detection limit: 100 OpG). Reproducibility and inter-test correlations were high with (R2 > 0.8). A correlation of oocyst excretion with diarrhoea could not be established so samples with different faecal consistencies should be taken. Pooled samples (by litter) should be comprised of several individual samples from different animals. Conclusions Since oocyst excretion by C. suis-infected piglets is usually short the right timing and a sufficiently sensitive detection method are important for correct diagnosis. Oocyst detection in faecal smears of samples taken repeatedly is the method of choice to determine extent and intensity of infection on a farm, and autofluorescence microscopy provides by far the lowest detection limit. Other methods for oocyst detection in faeces are less sensitive and/or more labour- and cost intensive and their usefulness is restricted to specific applications.
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Affiliation(s)
- Anja Joachim
- 1Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, A-1210 Vienna, Austria
| | - Bärbel Ruttkowski
- 1Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, A-1210 Vienna, Austria
| | - Daniel Sperling
- CEVA Santé Animale, 10 avenue de la Ballastière, 33500 Libourne, France
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Moreira ADS, Baptista CT, Brasil CL, Valente JDSS, Bruhn FRP, Pereira DIB. Risk factors and infection due to Cryptosporidium spp. in dogs and cats in southern Rio Grande do Sul. REVISTA BRASILEIRA DE PARASITOLOGIA VETERINARIA 2018. [DOI: 10.1590/s1984-296120180012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract This study investigated the frequency of oocysts of Cryptosporidium spp. in feces from dogs and cats in five municipalities in the southern region of the state of Rio Grande do Sul. The risk factors associated with infection were also investigated. Feces samples from 110 dogs and 18 cats were stained using the auramine method. At the time of feces sampling, a questionnaire with semi-open-ended questions was applied to the animal guardians and all data obtained underwent statistical analysis. The real frequency of oocysts of Cryptosporidium spp. was 24.63% (27 dogs and two cats). Only four samples of dog feces were diarrheic and no presence of oocysts was observed in any of them. Variables that represented risk factors for infection were: homemade food, untreated water, circulation of animals on grassy terrain and living in the same environment as other animals (cattle). The results made it possible to inferring that within the population studied, the frequency of parasitism due to Cryptosporidium spp. in dogs was relevant and emphasize the asymptomatic nature of this infection. The adopting control measures are highlighted, particularly in relation to variables that represent risk factors for this infection.
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An overview of methods/techniques for the detection of Cryptosporidium in food samples. Parasitol Res 2018; 117:629-653. [PMID: 29350281 DOI: 10.1007/s00436-017-5735-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 12/26/2017] [Indexed: 11/27/2022]
Abstract
Cryptosporidium is one of the most important parasitic protozoa of concern within the food production industry, worldwide. This review describes the evolution and its development, and it monitors the methodology that has been used for Cryptosporidium in food material since 1984, when the first publication appeared regarding the detection of Cryptosporidium parvum in food materials. The methods that are currently being used for the detection of Cryptosporidium oocysts in food material (mainly vegetables) and all of the other available published methods are discussed in this review. Generating more consistent and reliable data should lead to a better understanding of the occurrence, transport and fate of the oocysts in food material. Improvements in monitoring and developing effective methodology, along with food security, offer more practical possibilities for both the developed and developing worlds.
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A comparison of nested PCR assay with conventional techniques for diagnosis of intestinal cryptosporidiosis in AIDS cases from northern India. J Parasitol Res 2014; 2014:706105. [PMID: 24523958 PMCID: PMC3913498 DOI: 10.1155/2014/706105] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 10/29/2013] [Indexed: 12/02/2022] Open
Abstract
Cryptosporidiosis is a very important opportunistic infection and is responsible for significant morbidity and mortality in HIV/AIDS patients. Although current laboratory methods are generally considered adequate to detect high concentrations of oocysts, they fail to detect cases of cryptosporidiosis in many immunocompromised patients. The present study was done to determine the diagnostic efficacy of modified Ziehl-Neelsen (ZN), antigen detection ELISA, and a nested PCR assay for detection of Cryptosporidium in 58 adult AIDS cases with diarrhea from the ART clinic of Lok Nayak Hospital, New Delhi. Cryptosporidium was detected in 17 (29.4%), 39 (67.3%), and 45 (77.5%) cases by modified ZN staining, antigen ELISA, and nested PCR assay, respectively. Taking nested PCR as the gold standard, specificity of both modified ZN staining and Cryptosporidium antigen detection ELISA was 100% while the sensitivity of the tests was 37.8% and 86.6%, respectively. PCR was more sensitive than the other two diagnostic modalities but required a more hands-on time per sample and was more expensive than microscopy. PCR, however, was very adaptable to batch analysis, reducing the costs considerably. This assay can therefore have considerable advantages in the treatment of immunosuppressed individuals like AIDS patients, allowing their early diagnosis and decreasing the morbidity and the mortality.
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Pacheco FTF, Silva RKNR, Martins AS, Oliveira RR, Alcântara-Neves NM, Silva MP, Soares NM, Teixeira MCA. Differences in the detection of Cryptosporidium and Isospora (Cystoisospora) oocysts according to the fecal concentration or staining method used in a clinical laboratory. J Parasitol 2013; 99:1002-8. [PMID: 23829170 DOI: 10.1645/12-33.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Despite the availability of many parasitological methods for detection of Cryptosporidium and Isospora (Cystoisospora) belli in fecal samples, there are uncertainties about the accuracy of these techniques in laboratory practice. In this study, 27 formalin-fixed positive stool samples for Cryptosporidium and 15 for I. belli were analyzed by 2 concentration methods, sedimentation by centrifugation (SC) and formalin-ethyl acetate (FE), and by 3 tintorial techniques, modified Ziehl-Neelsen (ZN), safranin (SF), and auramine (AR). No significant differences were observed on Cryptosporidium identification between concentration methods, while a significantly higher number of I. belli oocysts (P < 0.0001) was detected in fecal smears concentrated by the SC than by the FE method. Fecal samples processed by FE produced a median oocyst loss to the fatty ring of 34.8% for Cryptosporidium and 45.4% for I. belli. However, FE concentration provided 63% of Cryptosporidium and 100% of I. belli slides classified as superior for microscopic examination. Regarding the efficiency of staining methods, a more significant detection of Cryptosporidium oocysts was observed in fecal smears stained by ZN (P < 0.01) or AR (P < 0.05) than by the SF method. Regular to high-quality slides for microscopic examination were mostly observed in fecal smears stained with AR or ZN for Cryptosporidium and with SF or ZN for I. belli. This study suggests a great variability in oocyst power detection by routine parasitological methods, and that the most frequent intestinal coccidians in humans have specific requirements for concentration and staining.
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Affiliation(s)
- Flávia T F Pacheco
- Faculdade de Farmácia, Universidade Federal da Bahia, Salvador, Bahia, Brazil, 40170-115
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Khurana S, Sharma P, Sharma A, Malla N. Evaluation of Ziehl-Neelsen staining, auramine phenol staining, antigen detection enzyme linked immunosorbent assay and polymerase chain reaction, for the diagnosis of intestinal cryptosporidiosis. Trop Parasitol 2013; 2:20-3. [PMID: 23508690 PMCID: PMC3593504 DOI: 10.4103/2229-5070.97234] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 06/16/2012] [Indexed: 01/08/2023] Open
Abstract
Background and Objectives: Cryptosporidiosis is a very important opportunistic infection and is responsible for significant morbidity and mortality in HIV/AIDS patients. The objective of this study is to evaluate Ziehl-Neelsen staining, auramine phenol staining, antigen detection enzyme linked immunosorbent assay and polymerase chain reaction, for the diagnosis of intestinal cryptosporidiosis. Materials and Methods: The study was designed to determine the efficacy of modified Ziehl-Neelsen (ZN), Auramine-Phenol (AP) staining, antigen detection enzyme linked immunosorbent assay (ELISA) and nested polymerase chain reaction (PCR) for detection of cryptosporidia in 671 HIV-seropositive patients, 353 HIV-seronegative patients including 198 children with diarrhea and 50 apparently healthy adults. Results: Cryptosporidium was detected in 26 (3.9%), 37 (5.5%), 32 (4.8%) and 40 (6%) HIV-seropositive and 8 (2.3%), 10 (2.9%), 9 (2.6%) and 9 (2.6%) HIV-seronegative patients by ZN staining, AP staining, antigen detection ELISA and PCR, respectively. None of the healthy controls were infected with Cryptosporidium. Based on criteria of ‘true positive’ samples, i.e. positive by any two of the four techniques out of ZN, AP, antigen detection ELISA and PCR, sensitivity of ZN and ELISA was 79.06% and 95.35% respectively. AP and PCR were found to be 100% sensitive. Specificity of ZN and ELISA was 100% while specificity of AP and PCR was 99.59% and 99.39% respectively. Conclusions: Auramine phenol staining is a rapid, sensitive and specific technique for diagnosis of intestinal cryptosporidiosis.
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Affiliation(s)
- Sumeeta Khurana
- Department of Parasitology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
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Murphy SC, Hoogestraat DR, Sengupta DJ, Prentice J, Chakrapani A, Cookson BT. Molecular diagnosis of cystoisosporiasis using extended-range PCR screening. J Mol Diagn 2011; 13:359-62. [PMID: 21458380 DOI: 10.1016/j.jmoldx.2011.01.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 12/21/2010] [Accepted: 01/04/2011] [Indexed: 11/27/2022] Open
Abstract
The differential diagnosis of diarrhea in immunocompromised patients encompasses many intestinal parasites including the coccidian Cystoisospora belli. Gastrointestinal infection with C. belli leads to cystoisosporiasis with diarrhea and, depending on host immune status, can cause extraintestinal disease. C. belli is usually diagnosed by examination of stool or intestinal biopsy specimens; however, the organism may be undetected using these test methods. Thus, more sensitive molecular tools for detection of pathogenic parasites are desirable. Herein is described a patient with AIDS who had persistent diarrhea of unknown cause. Microscopic examinations of stool and ileal biopsy specimens were initially unremarkable for any specific pathogen. Screening of DNA extracted from biopsy material using extended-range PCR primers recognizing conserved DNA sequences found in many fungi and parasites revealed infection with C. belli, which was confirmed at repeat histologic analysis. Extended-range PCR screening was used because the differential diagnosis was broad and other tools were not applied, yet this molecular approach led to the appropriate diagnosis and treatment of the condition. Thus, this approach offers a promising test for diagnosis of parasitic diseases that elude diagnosis using conventional methods.
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Affiliation(s)
- Sean C Murphy
- Department of Laboratory Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA.
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Hänscheid T, Valadas E. Diagnosis of cryptosporidiosis using PCR or auramine O with LED fluorescent microscopy: which end of the stick? Acta Trop 2009; 109:247-8; author reply 249. [PMID: 18822266 DOI: 10.1016/j.actatropica.2008.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Accepted: 08/13/2008] [Indexed: 11/25/2022]
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15
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Hänscheid T. The future looks bright: low-cost fluorescent microscopes for detection of Mycobacterium tuberculosis and Coccidiae. Trans R Soc Trop Med Hyg 2008; 102:520-1. [PMID: 18405928 DOI: 10.1016/j.trstmh.2008.02.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Revised: 02/25/2008] [Accepted: 02/25/2008] [Indexed: 11/30/2022] Open
Abstract
In many resource-poor countries, diagnosis of tuberculosis is based on microscopy of Ziehl-Neelsen-stained smears. However, the fluorescent stain auramine performs better and allows the detection of more positive smears. The limitation for its widespread use has been the high cost for fluorescent microscopes, especially the frequent replacement of the expensive light source, which lasts only 200-300 h. Novel light-emitting diodes (LED) are alternatives and last ten thousands of hours. Based on LEDs, rather inexpensive solutions for fluorescent microscopes are now available and thus auramine may be a cost-effective step to improve the diagnosis of tuberculosis in resource-poor countries.
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Affiliation(s)
- Thomas Hänscheid
- Instituto de Medicina Molecular, Faculdade de Medicina de Lisboa, Lisboa, Portugal.
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