Prevalencia de microscoporidios y otros parásitos intestinales en pacientes con infección por VIH, Bogotá, 2001 / Prevalence of microsporidia and other intestinal parasites in HIV infected patients from Bogotá[ a 2001 survey

Los parásitos intestinales oportunistas son protozoos que causan diarrea en pacientes infectados con el virus de inmunodeficiencia humana (VIH). Para determinar la prevalencia de microsporidios y otros par sitos oportunistas intestinales en pacientes infectados con el VIH con síntomas gastrointestinales y sistémicos, se estudiaron 115 pacientes que durante el 2001 consultaron al Hospital Santa Clara (33,0 por ciento), Clínica San Pedro-ISS (20,0 por ciento), Hospital Simón Bolívar (14,8 por ciento), San José (13,9 por ciento), Central de la Policía (6,1 por ciento), Compensar (5,2 por ciento), Liga de Lucha contra el Sida (2,6 por ciento), Hospital San Ignacio (2,6 por ciento) y Hospital Militar (1,7 por ciento). La edad promedio fue de 36 años con un rango de 18 a 71 años; 14 eran mujeres y 101 hombres. La metodología empleada fue la recolección por paciente de dos muestras de materia fecal seriadas para montaje directo, concentración, coloración de Zielh Neelsen modificada para diagnóstico de coccidios intestinales y coloraciones de cromotropo modificada, Gramcromotropo y calcoflúor para diagnóstico de microsporidios. La prevalencia de oportunistas fue de 10,4 por ciento para Cryptosporidium sp. En cuanto a microsporidios, se encontró que de 29 por ciento de positividad con cromotropo modificada como tamizaje, tan sólo 3,5 por ciento de las muestras se confirmaron como positivas con técnicas de calcoflúor y Gram-cromotropo. La prevalencia general de par sitos intestinales fue de 59,1 por ciento, de los cuales los principales patógenos fueron Blastocystis hominis con 25,2 por ciento y Entamoeba histolytica con 13 por ciento. En otros estudios con pacientes inmunosuprimidos por el VIH en Colombia, se han encontrado prevalencias de Cryptosporidium sp. menores que la hallada en esta investigación.

Nueva especie de Parathelohania (Microsporidia) en larvas de Anopheles aquasalis (Diptera: Culicidae) en Venezuela / New species of Parathelohania (Microsporidia) in larva of the Anopheles aquasalis (Diptera: Culicidae) in Venezuela

The symptoms of Anopheles aquasalis larvae naturally infected by a microsporidium, and the ultrastructure of the infecting spores is described. The larvae were maintained under laboratory conditions in salt concentrations of 10 g/l and 20 g/l of water. Daily recordings of the mortality of the larvae were made and the dates of change of instar were noted. Infected larvae were processed for transmission electronic microscopy using conventional methods at pH 7.2 and 260 mOsm/l. The infection by the microsporidia was positively correlated with an increase in the mean duration of the fourth instar of 2.88 to 6.33 days in 10 g/l of salt and of 2.47 to 6.14 days in 20 g/l of salt...

Nosema like organisms found in an immunocompetent human patient: first report in Central América

Stool samples of a immunocompetent hypertense 61 year old woman were stained by the Weber et al. method and studied by electronic microscopy. Mature microsporidia spores were found and according to their diplokaryotic muclei, as well as the typical polar filament with 12 coils, the organisms was classified as Nosema like genus

[New species of Parathelohania (Microsporidia) in larva of the Anopheles aquasalis (Diptera: Culicidae) in Venezuela]. / Nueva especie de Parathelohania (Microsporidia) en larvas de Anopheles aquasalis (Diptera: Culicidae) en Venezuela.

The symptoms of Anopheles aquasalis larvae naturally infected by a microsporidium, and the ultrastructure of the infecting spores is described. The larvae were maintained under laboratory conditions in salt concentrations of 10 g/l and 20 g/l of water. Daily recordings of the mortality of the larvae were made and the dates of change of instar were noted. Infected larvae were processed for transmission electronic microscopy using conventional methods at pH 7.2 and 260 mOsm/l. The infection by the microsporidia was positively correlated with an increase in the mean duration of the fourth instar of 2.88 to 6.33 days in 10 g/l of salt and of 2.47 to 6.14 days in 20 g/l of salt. Larval mortality also increased by approximately 50% during this instar in both salt concentrations. Development time and survival were not affected during the other immature stages. The mature spores found in the intestines of infected larvae were barrel shaped and measured approximately 2.6 x 2.4 mm. The exospore has a collar shaped prolongation at the posterior end of the spore. The spores are uninuclear with a posterior vacuole. The polar filament is anisofilar with nine rings, five with a diameter of 58 nm each and four with a diameter of 23 nm each. The polarplast is lamellate, and more tightly packed in the apical region. The reduction of the survival of A. aquasalis larvae infected with the microsporidia, and the increase in the development time suggest that this parasite might have a potential as a biological control of this pest. The microsporidium described here has similar characteristics to that of the genus Parathelohania. I suggest that the microsporidium found in A. aquasalis represents a new species and I propose the name Parathelohania aquasalensis. This is the first report of a microsporidium from a dipteran in Venezuela.

Diagnóstico laboratorial dos protozoários entéricos oportunistas em Goiânia, GO / Laboratorial diagnosis of intestinal protozoan opportunistic infections in Goiânia, GO

A criptosporidiose, isosporiase, ciclosporiase e as microsporidioses tornaram-se comuns em pacientes imunocomprometidos. O diagnostico destas doencas e importante, pois produzem quadro clinico semelhante, mas possuem manejo terapeutico e prognostico diferente. Visando avaliar a situacao do diagnostico destes parasitas, foram mapeados os laboratorios da rede do SUS e as unidades de saude no municipio de Goiania, GO

[Identification of Enterocytozoon bieneusi in a patient with sclerosing cholangitis and AIDS]. / Identificación de enterocytozoon bieneusi en un paciente con colangitis esclerosante y SIDA.

Enterocytozoon bieneusi is the most common microsporidian parasite found in patients with AIDS. We report the clinical features of a patient with chronic diarrhea, pancreatitis, and AIDS-related sclerosing cholangitis. Ultrasonography and endoscopic retrograde cholangiopancreatography disclosed intrahepatic and extrahepatic bile duct changes identical to those seen in sclerosing cholangitis. Enterocytozoon bieneusi was found in duodenum and peripapillary duodenum by means of light microscopy, and confirmed by PCR amplification of paraffin-embedded tissues with species-specific primers. Microsporidian infection should be suspected in patients with advanced immunodeficiency and AIDS-related sclerosing cholangitis in our country.

Diagnosis of Enterocytozoon bieneusi by PCR in stool samples eluted from filter paper disks.

We report a PCR-based assay for the detection of Enterocytozoon bieneusi. We extracted DNA from feces which had been applied to filter paper disks and evaluated four preserving solutions. Infected specimens were identified by electrophoresis of amplicons from concentrated formalin-fixed samples and unconcentrated fresh feces. Our findings demonstrate that this methodology is effective for sample collection, mailing, and diagnosis of this pathogen.

Identificación de Enterocytozoon bieneusi en un paciente con colangitis esclerosante y SIDA / Identification of Enterocytozoon bieneusi in a patient with sclerosing cholangitis and AIDS

Enterocytozoon bieneusi es el microsporidio que más comúnmente ha sido identificado en pacientes con SIDA. En este trabajo, se describen las manifestaciones clínicas de un paciente con diarrea crónica, pancreatitis y colangitis esclerosante asociada con SIDA. Los estudios por imágenes, con ultrasonografía y colangiopancreatografia retrógrada endoscópica, revelaron alteraciones en la vía biliar intra-y extrahepática, idénticas a las observadas en colangitis esclerosante. Se detectó Enterocytozoon bieneusi en duodeno y duodeno peripapilar por microscopia óptica y se confirmó por la reación en cadena de la polimerasa (PCR) utilizando primers específicos en muestras incluidas en parafina. La infección con microsporidios se debería sospechar en nuestro país en pacientes con inmunodeficiencia severa y colangitis esclerosante asociada con SIDA. (AU)

Identificación de Enterocytozoon bieneusi en un paciente con colangitis esclerosante y SIDA / Identification of Enterocytozoon bieneusi in a patient with sclerosing cholangitis and AIDS

Enterocytozoon bieneusi es el microsporidio que más comúnmente ha sido identificado en pacientes con SIDA. En este trabajo, se describen las manifestaciones clínicas de un paciente con diarrea crónica, pancreatitis y colangitis esclerosante asociada con SIDA. Los estudios por imágenes, con ultrasonografía y colangiopancreatografia retrógrada endoscópica, revelaron alteraciones en la vía biliar intra-y extrahepática, idénticas a las observadas en colangitis esclerosante. Se detectó Enterocytozoon bieneusi en duodeno y duodeno peripapilar por microscopia óptica y se confirmó por la reación en cadena de la polimerasa (PCR) utilizando primers específicos en muestras incluidas en parafina. La infección con microsporidios se debería sospechar en nuestro país en pacientes con inmunodeficiencia severa y colangitis esclerosante asociada con SIDA.

Horizontal transmission of Amblyospora albifasciati García and Becnel, 1994 (Microsporidia: amblyosporidae), to a copepod intermediate host and the neotropical mosquito, Aedes albifasciatus (Macquart, 1837).

The life cycle of Amblyospora albifasciati is characterized by three sporulation sequences involving the definitive mosquito host and a copepod intermediate host. Meiospores of A. albifasciati were infectious per os to adult females of the copepod Mesocyclops annulatus. All developmental stages in the copepod had unpaired nuclei, with sporulation involving the formation of a sporontogenic interfacial envelope and the production of a second type of uninucleate spore. These spores, formed in the ovaries of M. annulatus, were large, pyriform, and measured 10.4 x 4.8 microm. They infected Aedes albifasciatus larvae when ingested to initiate a sequence that involves schizogony and gametogony and ends with plasmogamy and nuclear association to form diplokaryotic meronts. Oval binucleate spores (9.3 x 3.1 microm) are formed in the adult mosquito and are responsible for vertical transmission to the filial generation.

Microsporidia and acquired immunodeficiency syndrome

Microsporidia is a common term that has been used to refer to a group of eukaryotic, obligate intracellular protozoan parasites belonging to the phylum Microspora. They are important agricultural parasites, contaminating commercial insects; they are also important by infecting laboratory rodents, rabbits and primates. Ever since the early cases found by Magarino Torres, who reported the presence of Encephalitozoon in a patient suffering of a meningoencephalomyelitis, some human pathology caused by microsporidia has been described. However, only after the acquired immunodeficiency syndrome outbreak have these organisms appeared as significant etiological agents in different pathologies. Even so, they remain underestimated. In the present article, the importance of microsporidia for the human pathology in immunocompromised host has been stressed

Microsporidiosis ocular: primer caso en un preescolar inmunocompetente reportado en Venezuela / Ocular microsporidiosis: first case to immunocompetent preschool in Venezuela

Este informe presenta el primer caso de queratitis producida por microspora reportado en Venezuela, en un paciente immunocomprometido de 5 años y 10 meses de edad, sin antecedentes de traumatismo ocular, quien consultó por presentar, desde hacía 8 días, molestias en el ojo izquierdo. El examen biomicroscópico revela la presencia de queratitis punctata. Se practicó estudio parasitológico y microbiológico de secreción conjuntival, así como raspado de epitelio corneal, confeccionándose extendidos y coloreándose mediante las técnicas de Kinyoun, Gram, PAS y Giemsa. Se observaron al microscopio de luz con objetivo de inmersión, pudiendo constatar la presencia de estructuras compatibles morfológica y tintorialmente con esporas de microspora, algunas de las cuales estaban libres y otras eran intracelulares, de forma esférica u ovales, con tamaños comprendidos entre 1,5 y 2,5 um de diámetro X 2,5 a 3,0 um. El paciente recibió tratamiento local utilizando colirio a base de corticoesteroides y sulfisoxazol seis veces al día, y por vía oral 200 mg diarios de albendazol. Todo el tratamiento duró catorce días, lográndose desaparición de los síntomas, restitución ad integrum del epitelio corneal y desaparición de las esporas en los extendidos confeccionados con la secreción ocular

[Microsporidian spores in the stool specimens of toddlers, with or without diarrhea, from Tucumán, Argentina]. / Esporas de microsporidios en las heces de niños de corta edad, con y sin diarrea, de Tucumán, Argentina.

An investigation has been carried out from September 1995 to December 1997 to search for microsporidian spores in the stool specimens of 344 toddlers aged 1 to 24 months, hospitalized at a pediatric institution in Tucumán. They were classified in two groups: I, made up of 222 children suffering from severe diarrheas, and II by 122 affected by different pathologies, except gastroenteritis. The detection of microsporidia was done by light microscopy in smears of stained stool specimens by using the Weber modified Kokoskin method. Copro-parasitological and coprobacteriological studies were also carried out and the nutritional status of each child was determined. In group I, microsporidia were found in 12/122 cases (7.2%), 4/68 belong to eutrophic children (5.9%), and 12/137 to undernourished children (8.8%); 8/16 positives were found to be related with other enteropatogenics. In group II, microsporidia were detected in 10/122 (8.2%), 4/47 in eutrophic children (8.5%), 4/54 in undernourished children (7.4%) and without data in two cases. They were related with other enteropatogenics in 5/10 positives. Tucumán can be estimated as an area with a low rate of HIV infection in toddlers, then it can be estimated that the studied sample was essentially HIV negative. The occurrence of microsporidia was important and did not show significant differences between toddlers with or without diarrhea, eutrophic or undernourished children.

[Microsporidiasis in AIDS patients with chronic diarrhea. Expieriences at the National Institute of Nutrition "Salvador Zubrirán"]. / Microsporidiasis en pacientes con SIDA y diarrea crónica. Experiencia en el Instituto Nacional de la Nutrición "Salvador Zubirán".

BACKGROUND: Microsporidium sp. has been considered as a rare cause of diarrhea in AIDS patients. However, the improvement of some histochemical stains in the analysis of small bowel biopsies has shown an increase in its prevalence. In Mexico there are no series reporting intestinal microsporidiasis. DESIGN: Small bowel biopsies of 98 patients with AIDS and chronic diarrhea stained with HE and Giemsa were reviewed (January 1987-December 1994). The clinical, demographic and laboratory information was obtained from the clinical charts. RESULTS: In 50 patients an opportunistic microorganism was identified in the small bowel biopsy (51%). Microsporidium sp. was identified in 30 patients (31%). The clinical charts were reviewed in all but six cases. Of the 24 patients with microsporidiasis as the cause of diarrhea, 17 were male and seven female with a median age, of 33 years, old. Homosexuality was the main risk factor in males (11/17), and blood transfusion in females (4/7). A low socioeconomical classification was found in 75% cases. The initial manifestation of AIDS was diarrhea in 16/24 (67%), CD4 count cell below 200 mm3 was identified in 13/24 patients and more than 200 mm3 in 2/24. The stool examination and the original histologic interpretations were negative for Microsporidium sp. Lymphoplasmocytic inflammatory infiltrate with eosinophils in the lamina propia and atrophy was frequently seen. A pale red and gray color was observed in spore and merogonial phases of Microsporidium stained with Giemsa. CONCLUSION: Microsporidium sp. was present as the only pathogen in 31% of the small bowel biopsies reviewed by light microscopy. Diarrhea due to Microsporidium sp. is frequently seen in advanced stages of AIDS with CD4 count cell below 200 mm3 Giemsa stain in the evaluation of small biopsies is a cheap and useful method to, identify Microsporidium sp.

Esporas de microsporidios en las heces de niños de corta edad, con y sin diarrea, de Tucumán, Argentina / Microsporidian spores in the stool specimens of toddlers, with or without diarrhea, from Tucumßn, Argentina

An investigation has been carried out from September 1995 to December 1997 to search for microsporidian spores in the stool specimens of 344 toddlers aged 1 to 24 months, hospitalized at a pediatric institution in Tucumßn. They were classified in two groups: I, made up of 222 children suffering from severe diarrheas, and II by 122 affected by different pathologies, except gastroenteritis. The detection of microsporidia was done by light microscopy in smears of stained stool specimens by using the Weber modified Kokoskin method. Copro-parasitological and coprobacteriological studies were also carried out and the nutritional status of each child was determined. In group I, microsporidia were found in 12/122 cases (7.2), 4/68 belong to eutrophic children (5.9), and 12/137 to undernourished children (8.8); 8/16 positives were found to be related with other enteropatogenics. In group II, microsporidia were detected in 10/122 (8.2), 4/47 in eutrophic children (8.5), 4/54 in undernourished children (7.4) and without data in two cases. They were related with other enteropatogenics in 5/10 positives. Tucumßn can be estimated as an area with a low rate of HIV infection in toddlers, then it can be estimated that the studied sample was essentially HIV negative. The occurrence of microsporidia was important and did not show significant differences between toddlers with or without diarrhea, eutrophic or undernourished children.(AU)

Esporas de microsporidios en las heces de niños de corta edad, con y sin diarrea, de Tucumán, Argentina / Microsporidian spores in the stool specimens of toddlers, with or without diarrhea, from Tucumßn, Argentina

An investigation has been carried out from September 1995 to December 1997 to search for microsporidian spores in the stool specimens of 344 toddlers aged 1 to 24 months, hospitalized at a pediatric institution in Tucumßn. They were classified in two groups: I, made up of 222 children suffering from severe diarrheas, and II by 122 affected by different pathologies, except gastroenteritis. The detection of microsporidia was done by light microscopy in smears of stained stool specimens by using the Weber modified Kokoskin method. Copro-parasitological and coprobacteriological studies were also carried out and the nutritional status of each child was determined. In group I, microsporidia were found in 12/122 cases (7.2), 4/68 belong to eutrophic children (5.9), and 12/137 to undernourished children (8.8); 8/16 positives were found to be related with other enteropatogenics. In group II, microsporidia were detected in 10/122 (8.2), 4/47 in eutrophic children (8.5), 4/54 in undernourished children (7.4) and without data in two cases. They were related with other enteropatogenics in 5/10 positives. Tucumßn can be estimated as an area with a low rate of HIV infection in toddlers, then it can be estimated that the studied sample was essentially HIV negative. The occurrence of microsporidia was important and did not show significant differences between toddlers with or without diarrhea, eutrophic or undernourished children.

[Trichome staining method applied to stools from HIV-infected patients with diarrhea, for microsporidia investigation]. / Aplicação de método de coloração tricrômica, em fezes diarréicas de infectados pelo HIV, para pesquisa de microsporídios.

The microsporidia have been involved in several clinical manifestations in patients with AIDS, of whom diarrhoea is the commonest. The diagnosis of microsporidiasis depended on invasive procedures and the identification of the organisms is made by electron microscopy. The modified trichrome staining method allows that the diagnosis be made without such procedures by using light microscopy. In the present work, the modified trchrome method was applied in stools from 62 patients with diarrhoea, who had asymptomatic HIV infection or AIDS. Of the 62 samples analyzed, there was detection of microsporidial spores in one. This work confirms the existence of such protozoans in our patients, associated with manifestations of chronic diarrhoea in patients with AIDS who have severe immunodeficiency and ascertains that this staining method allows satisfactory identification of microsporidia from faeces, as well points out some directions to further studies.