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David S. Lindsay - One of the best experts on this subject based on the ideXlab platform.
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Cystoisospora, Cyclospora, and Sarcocystis*
Manual of Clinical Microbiology, 2015Co-Authors: David S. Lindsay, Louis M. WeissAbstract:“Cystoisospora, Cyclospora, and Sarcocystis” provides an overview of the life cycles, pathogenesis, diagnosis, and treatment of these important parasites. These coccidial parasites have an environmentally resistant oocyst stage in their life cycles. They remain an important cause of diarrhea in patients in developing countries, and foodborne outbreaks still occur in developed countries. Humans are the only definitive hosts for Cystoisospora belli and Cyclospora cayetanensis and pass unsporulated oocysts in their stools. Sarcocystis requires two hosts. Humans are definitive hosts for S. hominis and S. suihominis and become infected after ingesting undercooked meat of bovids (cattle, buffalo) and pigs, respectively. Humans pass sporulated oocysts and sporocysts in their stools. Humans are also accidental intermediate hosts for one or more Sarcocystis species, and most cases are observed in Southeast Asia. Muscle sarcocysts are associated with fever and muscle pain. Diagnosis of Cystoisospora, Cyclospora, and Sarcocystis is based on microscopic examination of stool samples using acid-fast-stained slides or with UV microscopy. PCR-based methods of stool examination for oocysts have been developed. There are currently no serologic tests available to detect antibodies to these parasites and aid in their diagnosis. Combination antiretroviral therapy (cART) is associated with a better prognosis in AIDS patients, but clinical episodes still occur even in some patients on cART. Treatments for acute Cystoisospora and Cyclospora infections are available and effective. Apparent drug failures are most likely related to poor drug absorption or distribution rather than to true drug resistance.
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Cystoisospora canis apicomplexa sarcocystidae development of monozoic tissue cysts in human cells demonstration of egress of zoites from tissue cysts and demonstration of repeat monozoic tissue cyst formation by zoites
Veterinary Parasitology, 2013Co-Authors: Alice E. Houk, David S. LindsayAbstract:Sporozoites of Cystoisospora canis penetrated and developed to monozoic tissue cysts in 4 human, 1 monkey, 1 bovine and 2 canine cell lines. No asexual division was documented although multiple infection of a single cell was observed. Examination of cultures using transmission electron microscopy demonstrated that they were monozoic tissue cysts and contained a single sporozoite. The appearance of monozoic tissue cysts in all cell lines was similar but the parasitophorous vacuole surrounding some sporozoites in DH82 dog macrophages was swollen. Monozoic tissue cysts were observed for up to 127 days in human pigmented retinal epithelial cells. Treatment of cell cultures containing monozoic tissue cysts with 0.75 sodium taurocholic acid and 0.25% trypsin stimulated egress of zoites (former sporozoites) from tissue cysts. Zoites collected from monozoic tissue cysts were able to penetrate and develop to monozoic tissue cysts in new host cells. Monozoic tissue cysts survived exposure to acid pepsin solution indicating that they would be orally infectious. The tissue cyst wall surrounding zoites did not autofluoresce as did oocyst and sporocyst walls exposed to UV light. We believe that C. canis can be used as a model system to study extra-intestinal monozoic tissue cysts stages of Cystoisospora belli of humans.
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DEVELOPMENT AND ULTRASTRUCTURE OF Cystoisospora CANIS NEMESÉRI, 1959 (SYN. ISOSPORA CANIS) MONOZOIC CYSTS IN TWO NONCANINE CELL LINES
The Journal of parasitology, 2009Co-Authors: Sheila M. Mitchell, Anne M. Zajac, David S. LindsayAbstract:Cystoisospora canis is a coccidial parasite of the intestinal tract that can cause severe disease in dogs. Clinical signs include watery diarrhea, vomiting, fever, and weight loss. Extraintestinal stages of Cystoisospora spp. have been demonstrated in the mesenteric lymph nodes of paratenic hosts. Information on the biology of extraintestinal stages of canine Cystoisospora species is limited. The current study examined the development of C. canis in 2 noncanine cell lines and the ultrastructure of the monozoic cysts that formed. Monolayers of bovine turbinate cells and African green monkey kidney cells were grown on coverslips and inoculated with excysted C. canis sporozoites. Coverslips were collected on various days and fixed and stained for light microscopy (LM) or transmission electron microscopy (TEM). A single, centrally located, slightly crescent-shaped sporozoite surrounded by a thick cyst wall within a parasitophorous vacuole was observed with the use of LM and TEM. No division and no multinucleated stages were observed with either LM or TEM. With TEM, typical organelles of sporozoites were observed, such as rhoptries, dense granules, a crystalloid body, polysaccharide granules, and a conoid. The structure and ultrastructure of C. canis monozoic cysts produced in vitro are similar to extraintestinal cysts of other Cystoisospora species in experimentally infected animals and those of Cystoisospora belli observed in immunocompromised humans. This is the first study that fully demonstrates in vitro the development of what structurally resemble extraintestinal cysts of a Cystoisospora spp.
Márcia Benedita De Oliveira-silva - One of the best experts on this subject based on the ideXlab platform.
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chronic Cystoisospora belli infection in an hiv aids patient treated at the specialized assistance service in porto velho county rondonia
Revista Da Sociedade Brasileira De Medicina Tropical, 2019Co-Authors: Flavia Serrano Batista, Márcia Benedita De Oliveira-silva, Lais De Souza Miranda, Roger Lafontaine Mesquita Taborda, Maiara Cristina Ferreira Soares, Najla Benevides MatosAbstract:Cystoisospora belli infection manifests as diarrhea, and can potentially progress to malabsorption in HIV patients. Here, we report a case of C. belli infection in an HIV/AIDS patient with chronic diarrhea symptoms for at least 2 years. Coproscopic analyses based on direct technique and modified Ziehl-Neelsen technique without a commercial kit were performed. The current case report highlights the protocol to be adopted in coproscopic analyses applied to HIV patients. The importance of including the appropriate parasitological testing of patients with chronic intestinal isosporiasis in parasitological test routines must be considered.
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Ultrastructural aspects of Cystoisospora belli (syn. Isospora belli) in continuous cell lines.
Microscopy research and technique, 2014Co-Authors: Deisy Vivian De Resende, Dnieber Chagas De Assis, Múcio Flávio Barbosa Ribeiro, Marlene Cabrine-santos, Jacob K. Frenkel, Dalmo Correia, Márcia Benedita De Oliveira-silvaAbstract:Cystoisospora belli is an opportunistic protozoan that causes human cystoisosporiasis, an infection characterized by diarrhea, steatorrhea, abdominal pain, fever, and weight loss. The lack of animal models susceptible to C. belli, and the difficulty in obtaining clinical samples with fair amounts of oocysts have limited the research pertaining to the basic biology of this parasite. This study aimed to describe the ultrastructure of endogenous stages of C. belli in Monkey Rhesus Kidney Cells (MK2) and Human Ileocecal Adenocarcinoma cells (HCT-8). Zoites of C. belli exhibited typical morphological features of coccidia, which included a trilaminar pellicle, an apical complex formed by a conoid, polar rings, rhoptries, and micronemes, in addition to dense granules and the endoplasmic reticulum. No crystalloid body was observed but various lipid and amylopectin granules were usually present in the cytoplasm of zoites. We observed a tendency of the endoplasmic reticulum of the host cell to be located near the parasitophorous vacuole membrane. Merozoites were formed by endodyogeny and during replication, the apical complex of the mother cell remained intact. The formation of gametes or oocysts was not observed. The ultrastructural findings of C. belli are further evidence of its proximity to Sarcocystidae family members and corroborate their reclassification as Cystoisospora spp.
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Prevalence and genetic characterization of Cryptosporidium spp. and Cystoisospora belli in HIV-infected patients
Revista do Instituto de Medicina Tropical de Sao Paulo, 2013Co-Authors: Dnieber Chagas De Assis, Deisy Vivian De Resende, Marlene Cabrine-santos, Dalmo Correia, Márcia Benedita De Oliveira-silvaAbstract:Cryptosporidium spp. and Cystoisospora belli are monoxenic protozoa that have been recognized as the causative agents of chronic diarrhea in immunocompromised individuals, especially HIV-infected subjects. The objective of this study was to evaluate the frequency of these intestinal protozoa in HIV-positive patients in the Triângulo Mineiro region of Brazil and to correlate the presence of these infections with clinical, epidemiological and laboratory data of the patients. Oocysts were detected in stool samples of 10 (16.9%) of the 59 patients studied, while Cryptosporidium spp. were present in 10.1% (6/59) and C. belli in 6.7% (4/59). The frequency of these parasites was higher among patients with diarrheic syndrome and CD4+ T lymphocyte counts < 200 cells/mm 3 , demonstrating the opportunistic characteristic of these infections. A significant association was observed between the lack of adherence to antiretroviral therapy and the presence of Cryptosporidium spp. and/or C. belli. Parasitism with Cryptosporidium spp. was more frequent in February and April, the months following the period of high rainfall. The same was not observed for C. belli. Genetic characterization of two isolates led to the identification of Cryptosporidium parvum, one of the main species associated with the zoonotic transmission of cryptosporidiosis.
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Polymorphisms in the 18S rDNA gene of Cystoisospora belli and clinical features of cystoisosporosis in HIV-infected patients.
Parasitology research, 2010Co-Authors: Deisy Vivian De Resende, Marlene Cabrine-santos, Dalmo Correia, Eliane Lages-silva, André L. Pedrosa, Wendell Sérgio Ferreira Meira, Márcia Benedita De Oliveira-silvaAbstract:Intraspecific variability among Cystoisospora belli isolates and its clinical implications in human cystoisosporosis have not been established. In this study, the restriction fragment length polymorphisms in a 1.8-kb amplicon of the small subunit ribosomal DNA (SSU rDNA) of the parasite was investigated in 20 C. belli-positive stool samples obtained from 15 HIV-infected patients. Diarrheic syndrome was observed in all patients with cystoisosporosis and the number of diarrheic episodes per patient during hospitalization ranged from 1 to 26 (mean of 9.64 ± 9.30), with a mean duration of 2 to 12 days (mean of 5.90 ± 3 days). Three restriction profiles (RF) were generated with MboII digestion, which were named RFI, RFII, and RFIII. Two isolates obtained from a patient with extraintestinal cystoisosporosis showed distinct restriction profiles with MboII. This study demonstrates that patients can be infected with different C. belli genotypes, and this information may be useful for identifying new C. belli genotypes infecting humans.
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Experimental infection of murine and human macrophages with Cystoisospora belli.
Acta tropica, 2009Co-Authors: Deisy Vivian De Resende, Dnieber Chagas De Assis, Eliane Lages-silva, Aluízio Prata, Márcia Benedita De Oliveira-silvaAbstract:Extraintestinal cystoisosporosis by Cystoisospora belli has already been reported in HIV/AIDS patients, generally involving preferential invasion of mesenteric and trachaeobronchial lymph nodes, liver and spleen by unizoic cysts of this parasite, which may infect macrophages. To test this hypothesis, murine and human macrophages were exposed to sporozoites of C. belli and cultures were observed daily after contact with these cells. The parasites penetrated and multiplied by endodyogeny in both cell types and inserted themselves inside perinuclear vacuoles. After 48 h, extracellular parasites were removed from macrophage cultures and incubated in Monkey Kidney Rhesus cells (MK2) where there was intense multiplication. This is the first report of infection of macrophages by this parasite, which supports the hypothesis that these could act as C. belli host cells in extraintestinal sites.
Deisy Vivian De Resende - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructural aspects of Cystoisospora belli (syn. Isospora belli) in continuous cell lines.
Microscopy research and technique, 2014Co-Authors: Deisy Vivian De Resende, Dnieber Chagas De Assis, Múcio Flávio Barbosa Ribeiro, Marlene Cabrine-santos, Jacob K. Frenkel, Dalmo Correia, Márcia Benedita De Oliveira-silvaAbstract:Cystoisospora belli is an opportunistic protozoan that causes human cystoisosporiasis, an infection characterized by diarrhea, steatorrhea, abdominal pain, fever, and weight loss. The lack of animal models susceptible to C. belli, and the difficulty in obtaining clinical samples with fair amounts of oocysts have limited the research pertaining to the basic biology of this parasite. This study aimed to describe the ultrastructure of endogenous stages of C. belli in Monkey Rhesus Kidney Cells (MK2) and Human Ileocecal Adenocarcinoma cells (HCT-8). Zoites of C. belli exhibited typical morphological features of coccidia, which included a trilaminar pellicle, an apical complex formed by a conoid, polar rings, rhoptries, and micronemes, in addition to dense granules and the endoplasmic reticulum. No crystalloid body was observed but various lipid and amylopectin granules were usually present in the cytoplasm of zoites. We observed a tendency of the endoplasmic reticulum of the host cell to be located near the parasitophorous vacuole membrane. Merozoites were formed by endodyogeny and during replication, the apical complex of the mother cell remained intact. The formation of gametes or oocysts was not observed. The ultrastructural findings of C. belli are further evidence of its proximity to Sarcocystidae family members and corroborate their reclassification as Cystoisospora spp.
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Prevalence and genetic characterization of Cryptosporidium spp. and Cystoisospora belli in HIV-infected patients
Revista do Instituto de Medicina Tropical de Sao Paulo, 2013Co-Authors: Dnieber Chagas De Assis, Deisy Vivian De Resende, Marlene Cabrine-santos, Dalmo Correia, Márcia Benedita De Oliveira-silvaAbstract:Cryptosporidium spp. and Cystoisospora belli are monoxenic protozoa that have been recognized as the causative agents of chronic diarrhea in immunocompromised individuals, especially HIV-infected subjects. The objective of this study was to evaluate the frequency of these intestinal protozoa in HIV-positive patients in the Triângulo Mineiro region of Brazil and to correlate the presence of these infections with clinical, epidemiological and laboratory data of the patients. Oocysts were detected in stool samples of 10 (16.9%) of the 59 patients studied, while Cryptosporidium spp. were present in 10.1% (6/59) and C. belli in 6.7% (4/59). The frequency of these parasites was higher among patients with diarrheic syndrome and CD4+ T lymphocyte counts < 200 cells/mm 3 , demonstrating the opportunistic characteristic of these infections. A significant association was observed between the lack of adherence to antiretroviral therapy and the presence of Cryptosporidium spp. and/or C. belli. Parasitism with Cryptosporidium spp. was more frequent in February and April, the months following the period of high rainfall. The same was not observed for C. belli. Genetic characterization of two isolates led to the identification of Cryptosporidium parvum, one of the main species associated with the zoonotic transmission of cryptosporidiosis.
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Polymorphisms in the 18S rDNA gene of Cystoisospora belli and clinical features of cystoisosporosis in HIV-infected patients.
Parasitology research, 2010Co-Authors: Deisy Vivian De Resende, Marlene Cabrine-santos, Dalmo Correia, Eliane Lages-silva, André L. Pedrosa, Wendell Sérgio Ferreira Meira, Márcia Benedita De Oliveira-silvaAbstract:Intraspecific variability among Cystoisospora belli isolates and its clinical implications in human cystoisosporosis have not been established. In this study, the restriction fragment length polymorphisms in a 1.8-kb amplicon of the small subunit ribosomal DNA (SSU rDNA) of the parasite was investigated in 20 C. belli-positive stool samples obtained from 15 HIV-infected patients. Diarrheic syndrome was observed in all patients with cystoisosporosis and the number of diarrheic episodes per patient during hospitalization ranged from 1 to 26 (mean of 9.64 ± 9.30), with a mean duration of 2 to 12 days (mean of 5.90 ± 3 days). Three restriction profiles (RF) were generated with MboII digestion, which were named RFI, RFII, and RFIII. Two isolates obtained from a patient with extraintestinal cystoisosporosis showed distinct restriction profiles with MboII. This study demonstrates that patients can be infected with different C. belli genotypes, and this information may be useful for identifying new C. belli genotypes infecting humans.
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Experimental infection of murine and human macrophages with Cystoisospora belli.
Acta tropica, 2009Co-Authors: Deisy Vivian De Resende, Dnieber Chagas De Assis, Eliane Lages-silva, Aluízio Prata, Márcia Benedita De Oliveira-silvaAbstract:Extraintestinal cystoisosporosis by Cystoisospora belli has already been reported in HIV/AIDS patients, generally involving preferential invasion of mesenteric and trachaeobronchial lymph nodes, liver and spleen by unizoic cysts of this parasite, which may infect macrophages. To test this hypothesis, murine and human macrophages were exposed to sporozoites of C. belli and cultures were observed daily after contact with these cells. The parasites penetrated and multiplied by endodyogeny in both cell types and inserted themselves inside perinuclear vacuoles. After 48 h, extracellular parasites were removed from macrophage cultures and incubated in Monkey Kidney Rhesus cells (MK2) where there was intense multiplication. This is the first report of infection of macrophages by this parasite, which supports the hypothesis that these could act as C. belli host cells in extraintestinal sites.
Silvana Carnevale - One of the best experts on this subject based on the ideXlab platform.
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First report of Cystoisospora belli parasitemia in a patient with acquired immunodeficiency syndrome.
Acta parasitologica, 2016Co-Authors: Jorge Néstor Velásquez, Cecilia Di Risio, Cristina Etchart, Agustín Víctor Chertcoff, Mónica Gabriela Nigro, María Laura Pantano, Bibiana A. Ledesma, Natalia Vittar, Silvana CarnevaleAbstract:Cystoisospora belli in patients with the acquired immunodeficiency syndrome (AIDS) has been described as cause of chronic diarrhea and disseminated cystoisosporosis. Diagnosis of intestinal cystoisosporosis can be achieved at the tissue level in the villus epithelium of the small bowel. Disseminated cystoisosporosis is diagnosed by microscopy identification of unizoite tissue cysts in the lamina propria of the intestine. We report a case of disseminated cystoisosporosis in a human immunodeficiency virus (HIV)-infected patient with detection of parasitemia. We studied a 39-year old patient with AIDS and chronic diarrhea by analysis of stool and duodenal biopsy samples. Blood samples were also collected and examined by light microscopy and molecular techniques for C. belli DNA detection. The unizoite tissue cyst stages were present in the lamina propria, with unsporulated oocysts in feces. Zoites were present in blood smears and DNA of C. belli was detected in blood samples. Our study identified a new stage in the life cycle of C. belli. Detection of parasitemia is a novel and noninvasive tool for diagnosis of disseminated cystoisosporosis.
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Molecular characterization of Cystoisospora belli and unizoite tissue cyst in patients with Acquired Immunodeficiency Syndrome
Parasitology, 2010Co-Authors: Jorge Néstor Velásquez, Germán Astudillo Osvaldo, Cecilia Di Risio, Cristina Etchart, Agustín Víctor Chertcoff, Gladys Elisabet Perissé, Silvana CarnevaleAbstract:Cystoisospora belli is a coccidian protozoan that can cause chronic diarrhoea, acalculous cholecystitis and cholangiopathy in AIDS patients. We applied molecular methods to identify Cystoisospora at species level in AIDS patients presenting with and without the presence of unizoites in lamina propria. Coprological and histological analyses were performed in stool and/ or biopsy samples from 8 Cystoisospora-infected patients. DNA from the same samples was used to amplify 2 fragments of the SSU-rRNA gene and the ITS-1 region. Sequencing of the resulting amplicons identified C. belli infections in all cases, independent of the presence or absence of unizoite tissue cysts. Further work should be considered in order to find molecular targets related to strain variations in C. belli.
Alice E. Houk - One of the best experts on this subject based on the ideXlab platform.
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Cystoisospora canis apicomplexa sarcocystidae development of monozoic tissue cysts in human cells demonstration of egress of zoites from tissue cysts and demonstration of repeat monozoic tissue cyst formation by zoites
Veterinary Parasitology, 2013Co-Authors: Alice E. Houk, David S. LindsayAbstract:Sporozoites of Cystoisospora canis penetrated and developed to monozoic tissue cysts in 4 human, 1 monkey, 1 bovine and 2 canine cell lines. No asexual division was documented although multiple infection of a single cell was observed. Examination of cultures using transmission electron microscopy demonstrated that they were monozoic tissue cysts and contained a single sporozoite. The appearance of monozoic tissue cysts in all cell lines was similar but the parasitophorous vacuole surrounding some sporozoites in DH82 dog macrophages was swollen. Monozoic tissue cysts were observed for up to 127 days in human pigmented retinal epithelial cells. Treatment of cell cultures containing monozoic tissue cysts with 0.75 sodium taurocholic acid and 0.25% trypsin stimulated egress of zoites (former sporozoites) from tissue cysts. Zoites collected from monozoic tissue cysts were able to penetrate and develop to monozoic tissue cysts in new host cells. Monozoic tissue cysts survived exposure to acid pepsin solution indicating that they would be orally infectious. The tissue cyst wall surrounding zoites did not autofluoresce as did oocyst and sporocyst walls exposed to UV light. We believe that C. canis can be used as a model system to study extra-intestinal monozoic tissue cysts stages of Cystoisospora belli of humans.
