Emergent and re-emergent parasites in HIV-infected children: immunological and socio-environmental conditions that are involved in the transmission of Giardia spp. and Cryptosporidium spp.

ABSTRACT INTRODUCTION: Emergent and re-emergent waterborne protozoans have become a worldwide public health problem, especially among vulnerable groups. METHODS: This cross-sectional study evaluated 17 HIV-infected children and their families. RESULTS: A high (76.5%) percentage of parasite-infected children was observed, even among children with CD4+ T-cell counts of >200 cells/mm3. Giardia spp., Cryptosporidium spp. and Cyclospora spp. were observed in 41.2% of these children Low income, poor hygiene practices, and co-infection in domestic, peridomestic and scholastic environments were significant sources of these intestinal infections. CONCLUSIONS: Early diagnosis, timely treatment, and socio-educational interventions may improve the health conditions of this vulnerable population.

Parasitismo natural de bufalinos em Botucatu, SP, Brasil: III. Dinâmica do parasitismo gastro-intestinal em vacas e suas crias

Gastro-intestinal parasitism of 24 buffalo cows before parturition, and post-parturition, their infection and that of their respective calves during the following 30 weeks were studied. Willis, Hoffmann and whenever possible, the modified Gordon & Whitlock techniques were used for fecal examinations. Toxocara vitulorum eggs were the earliest forms encountered in calves feces, as follows: during the 1st week after birth, 58.33% of the calves were positive, and in the 4th week, 100% of these animals were positive. Eggs of Strongyloides sp were in the 1st week after birth in two of the calves and in the 5th week, all for them were positive. The next parasites to appear were the Coccidia of which oocysts were detected in the feces of two calves in the 2nd week after birth, and 58.33% of the calves were positive for these in the 3rd week, and in the 6th week, all calves shed oocysts in their feces. On the other hand, eggs of Strongylids were the last forms to appear in calves feces. However, despite their sporadic appearance in the feces, eggs of these parasites were observed continuously from the 11th week onwards, and at this point, the percentage of positive samples began to increase to reach its peak. Relatively to adult animals, eggs of T. vitulorum were observed in the feces of 11 cows, one or twice at most; eggs of Strongyloides sp were seen only once in the feces of four buffalo cows and eggs of Strongylids in 21 out of 24 cows. Oocysts of Coccidia were observed in 16 cows. Mechanisms of infestation of calves with these parasites are discussed.

The distribution of intestinal helminth infections in a rural village in Guatemala

Fecal egg count scores were used to investigate the distribution and abundance of intestinal helminths in the population of a rural village. Prevalences of the major helminths were 41% with Ascaris lumbricoides 60% with Trichuris trichiura and 50% with Necator americanus. All three parasites showed a highly aggregated distribution among hosts. Age/prevalence and age/intensity profiles were typical for both A. lumbricoides and T. trichiura with the highest worm burdens in the 50-10 year old children. For hookworm both prevalence and intensity curves were convex in shape with maximum infection levels in the 30-40 year old age class. Infected females had higher burdens of T. trichiura than infected males in all age classes of the population; there were no other effects of host gender. Analysis of associations between parasites within hosts revealed strong correlations between A. lumbricoides and T. lumbricoides and T. trichiura. Individuals with heavy infections of A. lumbricoides and T. trichiura showed highly significant aggregation within households. Associations between a variety of household features and heavy infections with A. lumbricoides and T. trichiura are described.

Plasmodium/intestinal helminth co-infections among pregnant Nigerian women

Hospital based studies were conducted to investigate the occurrence of Plasmodium/intestinal helminth co-infections among pregnant Nigerian women, and their effects on birthweights, anaemia and spleen size. From 2,104 near-term pregnant women examined, 816 (38.8%) were found to be infected with malaria parasites. Among the 816 parasitaemic subjects, 394 (48.3%) were also infected with intestinal helminths, 102 (12.5%) having mixed helminth infections. The prevalence of the helminth species found in stool samples of parasitaemic subjects examined was, Ascaris lumbricoides (19.1%), hookworm (14.2%), Trichuris trichiura (7%) Schistosoma mansoni (3.4%), Enterobius vermicularis (2%), Hymenolepis sp. (1.6%) and Taenia sp. (1%). Mothers with Plasmodium infection but without intestinal helminth infection had neonates of higher mean birthweights than those presenting both Plasmodium and intestinal helminth infections and this effect was more pronounced in primigravids. The mean haemoglobin values of malarial mothers with intestinal helminth infections were lower than those with Plasmodium infection but without intestinal helminth infections but these were not statistically significant. Severe splenomegaly was predominant among parasitaemic gravidae who also harboured S. mansoni infection in two of the hospitals studied.

Intestinal helminths of capybaras, Hydrochoerus hydrochaeris, from Venezuela

Quantitative parameters of intestinal helminth species and their potential relations to host characteristics in a population of capybaras (Hydrochoerus hydrochaeris) from Venezuela are reported for the first time. The intestines of 40 capybaras were collected during the 1992-annual harvest at Hato El Cedral. Six helminth species were found: 2 cestodes (Monoecocestus macrobursatum, M. hagmanni), 2 nematodes (Viannella hydrochoeri, Protozoophaga obesa), and 2 trematodes (Hippocrepis hippocrepis, Taxorchis schistocotyle). This is the first report for M. macrobursatum in Venezuela. Helminth abundance did not differ between sexes or age classes. Although patterns of distribution for all helminth species were overdispersed, the high prevalence found for all species (over 70%) and the high abundance observed for nematodes made it difficult to assess the effect that these helminths may produce on capybaras. Nevertheless, the negative associations found between the body condition of capybaras and helminth intensity for M. macrobursatum and V. hydrochoeri, might be pointing out potential host population regulatory role for these parasites which require further research.

Imunofluorescência para neuropeptídeos na mucosa nasal humana: avaliação de técnica para peptídeo intestinal vasoativo (VIP)

Os neuropeptídeos são neurotransmissores relevantes na fisiologia nasal e o conhecimento crescente acerca de seu papel na fisiopatologia de doenças nasais abre novas perspectivas. A sua investigação na mucosa nasal humana baseia-se em grande parte em marcação imunológica, método complexo e sujeito a inúmeros fatores de erro. Com o intuito de viabilizar este tipo de pesquisa em nosso meio, um método de imunofluorescência para peptídeo intestinal vasoativo (VIP) na mucosa nasal humana é proposto e avaliado. FORMA DE ESTUDO: Coorte transversal. MATERIAL E MÉTODO: Oito pacientes submetidos a cirurgia funcional do nariz têm um fragmento de mucosa coletado da concha inferior. O tecido foi fixado em solução de Zamboni (paraformaldeído 4% tamponado e ácido pícrico 0,4%), congelado em nitrogênio líquido e armazenado. Cortes de 14 µm foram realizados e submetidos à reação de imunofluorescência para VIP (Península Laboratories). As imagens microscópicas foram documentadas em fotografia convencional. A especificidade, sensibilidade e reprodutibilidade de execução foram avaliadas. A reprodutibilidade de interpretação de resultados foi avaliada através da comparação de graus de marcação (0 a 4) atribuídos às fotos por seis observadores. RESULTADOS: Os resultados mostraram ser o método suficientemente específico, sensível, além de reprodutível em sua execução. A interpretação de resultados mostrou depender do perfeito esclarecimento do observador no julgamento das imagens de imunofluorescência, mas mostrou uniformidade. CONCLUSÃO: O método proposto foi considerado útil na pesquisa de neuropeptídeos na mucosa nasal humana.

Importância da reabsorção do ferro da hemorragia intestinal provocada pela ação dos vermes na progressão da anemia

Foram estudados 10 doentes, portadores de anemia ancilostomótica e de grande parasitose. Foram determinados alguns parâmetros hematológicos como dosagem de hemoglobina, contagem de hemácias, hematócrito, volume corpuscular médio, hemoglobina corpuscular média, ferro sérico e siderofilina. Foram estudados o volume da perda de sangue intestinal, o ferro perdido nesta hemorragia e eliminado nas fezes, e o ferro reaborvido da hemorragia intestinal. Conclui-se que a reabsorção do ferro da hemoglobina por dia no tubo digestivo é de suma importância no retardamento da instalação da anemia ferropriva, causada pela parasitose ancilostomótica.

Campylobacter intestinal carriage among stray and pet dogs

The natural distribution of thermotolerant Campylobacter sp. in dogs (150 stray animals and 64 pets) was studied. Campylobacters were more frequently isolated (p<0.01) from stray dogs (51.3%) rather than from pet dogs (21.9%). All the biotypes described by Lior for C. jejuni and C. coli were found among stray animals, whereas only C. jejuni biotypes I and II and C. coli biotype II were found among pet dogs. The need for more studies related to the role of environmental sanitary conditions in the spreading of Campylobacter species is noted.

Tuberculose e parasitismo intestinal em população indígena na Amazônia brasileira

O objetivo do estudo foi estimar as freqüências de tuberculose e parasitoses intestinais na em comunidades indígenas da localidade de Iauareté (AM), em 2001. Estudo transversal (n=333) visando à obtenção de dados demográficos e amostras biológicas para exames de escarro e fezes. Dentre os 43 sintomáticos respiratórios, seis foram positivos na pesquisa de bacilos álcool-ácido resistentes no escarro. As parasitoses intestinais apresentaram freqüência significativamente maior entre a população Hüpda do que entre os índios que habitam os demais bairros (37,5% vs. 19,3% para Ascaris lumbricoides, 32,4% vs. 16,3% para Trichuris trichiura, 75% vs. 19,3% para ancilostomídeos, 75% vs. 35,4% para Entamoeba histolyticaD dispar e 33,3% vs. 10,7% para Giardia lamblia). Conclui-se que a tuberculose e o parasitismo intestinal são freqüentes nessas comunidades, exigindo medidas de controle e melhorias na assistência à saúde.

Atividade dissacaridásica intestinal da esquistossomose mansônica: estudo evolutivo em camundongos com diferentes cargas de infestação

A esquistossomose mansônica compromete vários órgãos, sendo o intestino e o fígado os mais agredidos. Com a intenção de verificar o comprometimento do intestino delgado, dependente da intensidade e do tempo de infecção pelo Schistosoma mansoni, analisou-se a atividade das dissacaridases — lactase, sacarase e maltase — em 112 camundongos, distribuídos em 3 grupos: grupo I — controle, grupo II — infestado com 30 cercárias, grupo III — infestado com 60 cercárias. Observamos uma diminuição da atividade lactásica, sacarásica e maltásica do intestino delgado, decorrente da infestação esquistossomdtica, do tempo de infestação e da alteração entre ambos. O íleo é o segmento que demonstrou maior sensibilidade a esquistossomose, tendo uma diminuição das suas dissacaridases a partir da fase inicial de infestação. Opostamente, o jejuno só mais tardiamente mostra essas alterações, exceto em relação a lactase. Detectou-se um aumento da atividade dissacaridásica, inclusive para a lactase, em todos os grupos, com a evolução etária dos animais, quantitativamente menor nos infestados. Cargas de 30 e 60 cercárias devem ser consideradas de mesmo porte, pois produziram ledução semelhante na atividade dissacaridásica.

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".

"In vitro" activity of gentian violet against asexual Plasmodium falciparum parasites

In order to investigate whether gentian violet exhibited "in vitro" inhibitory activity against Plasmodium falciparum, the Authors have carried out 20 sensitivity tests according to the microtechnique described by RIECK MANN et al.5. Results have shown inhibition of schizonts'maturation at the following concentration: 1/1000; 1/1500; 1/2000; 1/2500; 1/3000 and 1/4000, thus demonstrating inhibitory activity of the tested dye against asexual blood parasites. The present data suggest gentain violet may be possibly used in the prophylaxis of transfusion-acquired malaria.

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.

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).