Intestinal cryptosporidiosis. association with Pneumocystis carinii, cytomegalovirus and Candida sp. Infections

This is a case report of intestinal cryptosporidiosis diagnosed in histological specimen collected from autopsy. The patient was a child of 5 months admitted to the hospital with severe acute diarrhea associated with Pneumocystis carinii pneumonia, cytomegalic sialadenitis, oral and dermal candidiasis. The presence of multiple opportunistic infections in this case indicated immunodeficiency state. Cryptosporidium sp is a possible etiology of acute diarrhea in both immunodeficient and immunocompetent patients and has to be searched for at autopsy when diagnosis was not possible "in vivo".

Parasitological and serological studies on Amoebiasis and other intestinal parasitic infections in Recife and its suburban area, northeast Brazil

Parasitological examinations were carried out during April to August, 1987, with 187 out-patients of the IMIP hospital, located in the center of Recife City, and 464 inhabitants of several villages around Cabo City, 50 Km southeast of Recife, Pernambuco, Brazil. Approximately 71% of the IMIP patients and 92% of the Cabo inhabitants were infected with at least one species of intestinal parasite. There was minimum difference in the prevalence rate of Trichuris trichiura between two areas, whereas the prevalence rates of Ascaris lumbricoides, hookworms, Strongyloides stercoralis, Schistosoma mansoni and Entamoeba histolytica were higher in the inhabitants of the Cabo City area. Only Giardia lamblia was more prevalent in the out-patients of IMIP hospital. Test tube cultivation revealed that the prevalence rate of Necator americanus in both areas was much higher than that of Ancylostoma duodenale , and also that the prevalence rate of S. stercoralis of the IMIP patients and Cabo inhabitants were 4.5% and 9.6%, respectively. Six hundred and fifteen sera were serologically examined for amoebiasis by the gel diffusion precipitation test (GDP) and enzyme linked immunosorbent assay (ELISA) using the antigen prepared from axenically cultured trophozoite of E. histolytica (strain HM-ITMSS). No positive reaction was observed in all of the sera as examined by GDP, while 32 out of 615 sera were positive on ELISA.

Ascaris lumbricoides in neonate: evidence of congenital transmission of intestinal nematodes

Clinical and epidemiological study of a forty-days-old infant with a diarrheic condition and insufficient development led to the coprological diagnosis of ascariasis and possible congenital infection. Specific treatment with levamizole, resulted in clinical and parasitological cure, in addition to gain of weight up to normal levels. Maternal parasitism had been diagnosed two months before labor and proved beyond doubt during the ensuing epidemiological inquiry.

Parasitological and serological studies on amoebiasis and other intestinal parasitic infections in the rural sector around Recife, Northeast Brazil

Parasitological examinations were carried out during July to December, 1989, on 485 inhabitants of four villages in São Lourenço da Mata, 25 km northwest of Recife, Pernambuco, Brazil. Approximately 99.6% of the inhabitants were infected with at least one species of intestinal parasites. A high prevalence of Schistosoma mansoni (82.1%), hookworm (80.2%) Trichuris trichiura (69.9%), Ascaris lumbricoides (61.9%) and Entamoeba coli (36.7%) infections were demonstrated. Test tube cultivation revealed that the most common species of hookworm in this region was Necator americanus (88.4%), and also that the prevalence of Strongyloides stercoralis was 5.8%. Three hundred and thirty-four sera were serologically examined for amoebiasis by the gel diffusion precipitation test (GDP) and enzyme-linked immunosorbent assay (ELISA). No positive reaction was observed in all sera as examined by GDP, while 24 sera were positive by ELISA.

Non-colorectal intestinal tract carcinomas in inflammatory bowel disease: results of the 3rd ECCO Pathogenesis Scientific Workshop (II)

Patients with inflammatory bowel diseases (IBD) have an excess risk of certain gastrointestinal cancers. Much work has focused on colon cancer in IBD patients, but comparatively less is known about other more rare cancers. The European Crohn's and Colitis Organization established a pathogenesis workshop to review what is known about these cancers and formulate proposals for future studies to address the most important knowledge gaps. This article reviews the current state of knowledge about small bowel adenocarcinoma, ileo-anal pouch and rectal cuff cancer, and anal/perianal fistula cancers in IBD patients.

Antibodies against Entamoeba histolytica in individuals with intestinal amoebiasis presenting cysts and/or trophozoites in the feces

Serum samples were obtained from 154 individuals infected with Entamoeba histolytica (78 symptomatic and 76 asymptomatic). Twelve had trophozoites in the feces whereas 142 had only cysts. The sera were used to test the existence of antibodies anti-Entamoeba histolytica employing the Indirect Hemagglutination (IHA), Indirect Immunofluoresccnce (IFAT), Complement Fixation Reaction (CFR) and Counterimmunoelectrophoresis (CIEP). For those individuals with trophozoites in their feces, 75.0 were positive by IHA and IFAT, 83.0 by CFR and 41.7 by CIEP. In individuals who had only cysts, positive results by the same tests were respectively, 5.6%, 12.0%, 19.0% and 5.6%. The difference in relation to the tilers of antibodies detected through IHA, IFAT, CFR and CIEP and in relation to the presence of trophozoites or cysts in the feces was significative for four immunological reactions when X², was employed (P < 0.05).

Intestinal parasites among Karitiana Indians from Rondônia State, Brazil

Gravity sedimentation parasitological examinations were performed in stool samples from 111 Karitiana Indians from Rondônia State, Brazilian Amazon Basin. Intestinal parasites were found in 43 samples (38.7%). Ascaris lumbricoides was the most prevalent helminth species (18.9%). Egg counts in samples positive for Ascaris suggested an overdispersed distribution of worm burdens in the host population. Age-distribution pattern of intestinal parasites among Karitiana Indians was found to be rather unusual: the highest prevalence (60.0%) was detected in the 12-to 16-year-old age group

Interacção Parasita-Hospedeiro e susceptibilidade de Leishmania infantum a fármacos

RESUMO As leishmanioses são doenças causadas por um protozoário intracelular pertencente à ordem Kinetoplastida, da família Trypanosomatidae, do género Leishmania. Os parasitas são transmitidos aos hospedeiros vertebrados por dípteros pertencentes à sub-família Phlebotominae. Devido à inexistência de vacinas a quimioterapêutica continua a representar o único mecanismo de prevenção e controlo. Os fármacos de primeira linha para o tratamento da leishmaniose visceral continuam a ser os antimoniais pentavalentes e a anfotericina B (AMB). A AMB lipossómica está a ser cada vez mais utilizada como 1ª linha. O conhecimento do(s) mecanismo(s) utilizados pelos parasitas, responsáveis pela resistência, é fundamental de modo a permitir o desenvolvimento de novos fármacos anti-Leishmania que possam substituir e/ou complementar os fármacos existentes, de uma forma eficaz assim como contribuir para o desenvolvimento de metodologias para avaliar e monitorizar a resistência. Espera-se do modelo animal a reprodução da infecção na Natureza. Os modelos canino e murino têm ajudado na compreensão dos mecanismos responsáveis pela patogénese e pela resposta imunitária à infecção por Leishmania. Sendo o cão o principal hospedeiro da infecção por L. infantum e o principal reservatório doméstico da leishmaniose visceral humana, procedeu-se à caracterização da evolução da infecção experimental em canídeos de raça Beagle através da análise clínica, hematológica, histopatológica, parasitária, assim com através da resposta imunitária desenvolvida. As alterações hematológicas observadas foram as associadas à leishmaniose visceral: anemia, leucopenia, trombocitopenia com aumento das proteínas totais e da fracção gama-globulina, e diminuição da albumina. Histologicamente observou-se nos órgãos viscerais uma reacção inflamatória crónica, acompanhada por vezes da formação de granulomas ricos em macrófagos. Apesar de todos os animais terem ficado infectados (confirmado pela presença do parasita nos vários tecidos e órgãos recolhidos na necrópsia), os únicos sinais clínicos observados transitoriamente foram adenopatia e alopécia. As técnicas moleculares foram significativamente mais eficazes na detecção do parasita do que os métodos parasitológicos convencionais. As amostras não invasivas (sangue periférico e conjuntiva) mostraram ser significativamente menos eficazes na detecção de leishmanias. No nosso modelo experimental não se observou a supressão da resposta celular ao antigénio parasitário e confirmou-se que, apesar de não protectora, a resposta humoral específica é pronunciada e precoce. A bipolarização da resposta imunitária Th1 ou Th2, amplamente descrita nas infecções experimentais por L. major no modelo murino, não foram observadas neste estudo. O facto dos animais não evidenciarem doença apesar do elevado parasitismo nos órgãos viscerais poderá estar relacionado com a expressão simultânea de citocinas de ambos os tipos Th1 e Treg, no baço, fígado, gânglio, medula óssea e sangue periférico. Neste estudo também se caracterizou o efeito da saliva do vector Phlebotomus perniciosus na infecção experimental de murganhos BALB/c com estirpes de L. infantum selvagem e tratada com AMB, inoculadas por via intradérmica. A visceralização da infecção ocorreu após a utilização da via de administração do inóculo que mais se assemelha ao que ocorre na Natureza. Apesar da disseminação dos parasitas nos animais co-inoculados com extracto de uma glândula salivar ter sido anterior à do grupo inoculado apenas com parasitas, não se detectaram diferenças significativas na carga parasitária, entre os três grupos, ao longo do período de observação pelo que, embora a saliva do vector esteja descrita como responsável pela exacerbação da infecção, tal não foi observado no nosso estudo. O aumento de expressão de citocinas esteve relacionado com o aumento do parasitismo mas, tal como no modelo canino, não se observou bipolarização da resposta imunitária. Os animais dos três grupos infectados parecem ter desenvolvido nos diferentes órgãos uma resposta mista dos tipos Th1 e Th2/Treg. Contudo, verificou-se a predominância da expressão Th1 (TNF-α), no fim do período de observação, o que pode estar relacionado com a resolução da infecção. Por outro lado, a presença de parasitas na pele dos animais inoculados com a estirpe L. infantum tratada com AMB permite colocar a hipótese da existência de parasitas resistentes na Natureza e destes poderem ser transmitidos. Após se ter verificado que a estirpe de L. infantum tratada com AMB tinha a capacidade de infectar e visceralizar no modelo murino, analisou-se o seu comportamento em dois dos principais vectores de L. infantum, Lutzomyia longipalpis e P. perniciosus. Os parasitas tratados com AMB apresentaram uma menor capacidade de permanecerem no interior do vector assim como um desenvolvimento mais lento apontando para uma menor capacidade de transmissão das estirpes resistentes a este fármaco, pelo que o tratamento com AMB poderá ser favorável à prevenção e controlo através da interrupção do ciclo de vida do parasita. De modo a determinar in vitro a susceptibilidade de Leishmania aos diferentes fármacos utilizados na terapêutica da leishmaniose humana e canina (Glucantime®, Fungizone®, miltefosine e alopurinol) comparou-se o sistema de promastigotas axénicos com o sistema amatigota-macrófago. Verificou-se que, para as estirpes estudadas, os resultados de ambos os sistemas não apresentavam diferenças significativas sendo a utilização do primeiro mais vantajosa ao ser menos moroso e de mais fácil execução. Seleccionaram-se estirpes quimio-resistentes in vitro, por exposição prolongada a doses crescentes de AMB, tendo-se verificado que os parasitas tratados, apresentaram uma menor susceptibilidade do que os não tratados à acção dos fármacos estudados, com excepção do alopurinol. A diminuição da susceptibilidade das estirpes aos fármacos utilizados poderá facilitar a dispersão de parasitas multiresistentes. Sendo a apoptose um dos mecanismos utilizados pelos parasitas para evitar a indução de uma resposta imune por acção de compostos anti- Leishmania, determinou-se o número de amastigotas apoptóticos assim como a produção de TNF-α e IL-10 pelos macrófagos tratados. Concluiu-se que os compostos conseguiram suprimir a produção de IL-10, inibidora da activação dos macrófagos, contudo nem a produção da citocina pro-inflamatória TNF- α nem a apoptose pareceram ser os principais mecanismos responsáveis à sobrevivência dos parasitas ao contacto com os fármacos.

Prevalence of intestinal parasitic infection in five farms in Holambra, São Paulo, Brazil

A parasitological survey was carried out on 222 inhabitants of five farms in Holambra, located 30 km north of Campinas, São Paulo, Brazil, on October 1992. Approximately 70% of the inhabitants were found to be infected with at least one species of intestinal parasite. The positive rates of 6 helminths and 7 protozoan species detected are as follows: 5.4% Ascaris lumbricoides; 8.6% Trichuris trichiura; 19.8% Necator americanus; 10.4% Strongyloides stercoralis; 14% Enterobius vermicularis; 0.9% Hymenolepis nana; 3.2% Entamoeba histolytica; 2.7% E. hartmanni; 9.9% E. coli; 14.0% Endolimax nana; 2.3% Iodamoeba butschlii; 10.4% Giardia lamblia; 37.8% Blastocystis hominis. The positive rates of helminth infection were generaly higher in the younger-group under 16 years-old than those in the elder group aged 16 or more, whereas the infection rates of protozoan species were higher in the elder group. The infection rate of Strongyloides was found to be 10.4% by a newly developed sensitive method (an agarplate culture methods).

Intestinal parasitism in the Xavánte Indians, Central Brazil

This paper reports the findings of a survey for intestinal parasites among the Xavánte Indians from Central Brazil. A. lumbricoides (25.0%) and hookworms (33.6%) were the two most common helminths; E. histolytica complex (7.8%) and G. lamblia (8.6%) the most common protozoans. The majority (58.5%) of positive individuals hosted only one species of helminth. Egg counts for helminths, and for A. lumbricoides in particular, were found to be not dispersed at random, with a few individuals, all of whom young children, showing very high counts. The prevalence rates of intestinal parasites for the Xavánte are below those reported for other Amerindian populations from Brazil.

Intestinal parasites in school food handlers in the city of Uberlândia, Minas Gerais, Brazil

In order to verify the presence of intestinal parasites in food handlers, stool samples were collected from 104 cooks and their helpers that were working in food preparation in 20 public elementary schools, in various areas of the city of Uberlândia, Minas Gerais, Brazil. The samples were collected during the months of November and December, 1988, in plastic flasks containing a 10% formaldehyde solution and processed by the Hoffmann, Pons & Janer method. The sediment was examined using triplicate slides. All individuals were females aged between 24 to 69 years. Intestinal parasites were found in 85.0% of the studied schools and 47.1% of the studied food handlers (cooks and helpers) were found to be positive. Among the 49 infected food handlers, 32 (65.3%) carried a single parasite and 17 (34.7%) carried two parasites. The following intestinal parasites were found: Giardia lamblia (21.1%), Entamoeba coli (21.1%), hookworms (9.6%), Ascaris lumbricoides (5.8%), Entamoeba histolytica (2.9%), Hymenolepis nana (1.9%), Strongyloides stercoralis (1.0%). These data emphasize the need for a rigid semi-annual control in all school food handlers, including diagnosis, specific treatment and orientation about the mechanisms of transmission of the intestinal parasites.

Intestinal spirochetosis: first cases reported in Brazil and the use of immunohistochemistry as an aid in histopathological diagnosis

Colonization of the colon and rectum by intestinal spirochetes is detected for the first time in Brazil in 4 of 282 (1.41%) patients who had undergone sigmoidoscopy and/or colonoscopy with a histopathological diagnosis of chronic non specific-colitis. This frequency is probably understimated, since surgically obtained specimens were not considered in the present study. Histopathological diagnosis was performed using routine stains like hematoxylin-eosin which showed the typical, of 3-µm thick hematoxyphilic fringe on the brush border of the surface epithelium, and by silver stains like the Warthin-Starry stain. Immunohistochemical procedures using two, polyclonal, primary antibodies, one against Treponema pallidum and the other against Leptospira interrogans serovar copenhageni serogroup Icterohaemorrhagiae cross-reacted with spirochetal antigen/s producing a marked contrast of the fringe over the colonic epithelium, preserving the spiral-shaped morphology of the parasite. In one case with marked diarrhea, immunohistochemistry detected spirochetal antigen/s within a cell in an intestinal crypt, thus demonstrating that the infection can be more widely disseminated than suspected using routine stains. Immunohistochemical procedures, thus, greatly facilitate the histological diagnosis of intestinal spirochetosis and may contribute to a better understanding of the pathogenesis of the disease. Transmission and scanning electron microscopy performed in one case showed that the spirochete closely resembled the species designated as Brachyspira aalborgi.

Intestinal microsporidiosis in HIV-positive patients with chronic unexplained diarrhea in Rio de Janeiro, Brazil: diagnosis, clinical presentation and follow-up

After the diagnosis of two cases of microsporidial intestinal infection in 1992, in Rio de Janeiro, we have started looking for this parasite in HIV-infected patients with chronic unexplained diarrhea. We have studied 13 patients from Hospital Evandro Chagas, IOC-FIOCRUZ. Fecal specimens from these patients were examined for the presence of Cryptosporidia and Microsporidia, in addition to routine examination. Spores of Microsporidia were found in the stools of 6 (46.1%) of the 13 patients studied, with 2 histological jejunal confirmations. The Microsporidia-infected patients presented chronic diarrhea with about 6 loose to watery bowel movements a day. Five infected patients were treated with Metronidazole (1.5 g/day). They initially showed a good clinical response, but they never stopped eliminating spores. After about the 4th week of therapy, their diarrhea returned. Two patients utilized Albendazole (400 mg/day-4 weeks) with a similar initial improvement and recurrence of the diarrhea. Intestinal Microsporidiosis seems to be a marker of advanced stages of AIDS, since 5 of our 6 infected patients were dead after a 6 month period of follow-up. The present study indicates that intestinal microsporidiosis may be a burgeoning problem in HIV-infected patients with chronic diarrhea in Brazil, which deserves further investigation.

Epidemiology and antimicrobial resistance of B. fragilis group organisms isolated from clinical specimen and human intestinal microbiota

Epidemiological aspects and the antimicrobial susceptibility profile of the Bacteroides fragilis group isolated from clinical and human intestinal specimens were examined in this study. B. fragilis group strains were isolated from 46 (37%) of 124 clinical specimens and the source of the samples was: Blood culture (3), intraabdominal infection (27), brain abscess (2), soft tissue infection (17), respiratory sinus (3), pleural aspirate (9), breast abscess (3), surgical infected wound (22), pelvic inflammatory disease (22), chronic otitis media (9) and miscellaneous (7). Intraabdominal and soft tissue infections were responsible for more than half of the clinical isolates. Susceptibility to penicillin, cefoxitin, tetracycline, metronidazole, chloramphenicol and clindamycin was examined. All isolates were susceptible to metronidazole and chloramphenicol. For clindamycin and cefoxitin the resistance rates observed were 21.7% and 10.9% respectively. Susceptibility profiles varied among the different species tested. A total of 37 species of B. fragilis group isolated from intestinal microbiota of individuals who had no antimicrobial therapy for at least 1 month before the sampling was also examined. All strains were also susceptible to chloramphenicol and motronidazole and the resistance rates to clindamycin and cefoxitin were 19.4% and 5.4% respectively. A few institutions, in Brazil, have monitored the antimicrobial susceptibility of B. fragilis group strains isolated from anaerobic infections. The resistance rates to cefoxitin and clindamycin and the variation in susceptibility patterns among the species isolated in this study emphasize the need for monitoring of susceptibility patterns of B. fragilis group organisms isolated, especially at our University Hospitals.