Comparação entre os métodos de Ziehl-Neelsen modificado e Acid-Fast-Trichrome para a pesquisa fecal de Cryptosporidium parvum e Isospora belli

Devido a crescente importância dos coccídios intestinais (Cryptosporidium, Isospora e Cyclospora) como parasitos oportunistas, é fundamental para os laboratórios diferenciar morfologicamente estes protozoários; a técnica de Ziehl-Neelsen modificada (ZNm) é amplamente utilizada para este fim; recentemente, foi proposto um novo procedimento, a coloração combinada do ácido tricrômico (Acid-Fast-Trichrome - AFT). O objetivo do presente estudo foi comparar os processos AFT e ZNm para a detecção destes coccídios em amostras fecais de pacientes portadores do vírus VIH. Foram selecionados dois grupos de indivíduos, para inclusão no estudo, segundo a presença (n=60) ou ausência de diarréia (n=60). As amostras de fezes foram coletadas em solução de formalina 10% e os esfregaços fecais preparados i) diretamente das fezes e ii) após concentração prévia a 500xg (10 minutos), foram submetidos aos diferentes processos de coloração. Considerando-se a positividade por técnica (AFT e ZNm), verificou-se a superioridade do procedimento de ZNm (n=19; 100% dos casos positivos) sobre o de AFT (n=8; 42,1%). Ambos possibilitaram a identificação dos 101 casos verdadeiramente negativos. Coccidiose intestinal foi mais frequente entre os pacientes que apresentaram diarréia (26,6%) em comparação à positividade observada entre os indíviduos assintomáticos (5%) sendo que C. cayetanensis não foi detectada em ambos os grupos. Foi de nosso interesse avaliar a aplicabilidade da técnica AFT para a coloração deste protozoário. Devido à sensibilidade e especificidade obtida neste estudo (100%), conclui-se que o método de ZNm continua sendo o mais indicado para o diagnóstico da criptosporidiose e isosporose, principalmente quando associado ao procedimento de centrífugo-concentração (500xg, 10 minutos). Embora a coloração AFT tenha baixo custo, faz-se necessário o seu aperfeiçoamento pois este procedimento permite o diagnóstico simultâneo dos coccídios intestinais (C. parvum, I. belli e C. cayetanensis) e dos microsporídios.

Morphometric study of the fibrosis and mast cell count in the circular colon musculature of chronic Chagas patients with and without megacolon

A morphometric study of the circular colon musculature was performed, in which the mast cell count was determined and the connective fibrous tissue in this layer was measured. The objective was to gain better understanding of Chagas megacolon morphology and contribute towards the knowledge of fibrosis pathogenesis in Chagas megas. An evaluation was made of 15 distal sigmoid rings from Chagas patients with megacolon (MCC), 15 without megacolon (CSMC) and 15 non-Chagas patients (NC). The rings were fixed in formol, embedded in paraffin, and 7mm thick sections were cut and stained using Azan-Heidenhain and Giemsa. The mast cell count and fibrosis were greater in the MCC group than in the CSMC and NC groups (p < 0.05; Kruskal-Wallis test) and there was no significant difference between the latter two. The fibrosis and increased mast cell count in the colon musculature of the MCC group possibly indicates that there is a relationship between mastocytosis and fibrosis, as has already been demonstrated in other pathologies.

Comparative clinical and ultrasound study of egg-negative and egg-positive individuals from Schistosoma mansoni low morbidity endemic areas, and hospitalized patients with hepatosplenic disease

Two hundred and twenty three subjects from a Schistosoma mansoni low morbidity endemic area and nine hospitalized hepatosplenic patients were submitted to stool test and clinical examination and abdomen ultrasound assessments. According to stool examination and ultrasound results, they were grouped as follows: G1 - 63 Schistosoma mansoni egg-negative individuals; G2 - 141 egg-positive patients and without evidence of periportal fibrosis; G3 - 19 egg-positive patients with periportal echogenicity (3-6mm); and G4 - 9 hepatosplenic patients with periportal echogenicity (> 6mm). Hepatomegaly detected by physical examination of the abdomen evaluated in the midclavicular line was verified in G1, G2 and G3, respectively, in 11.1, 12.1 and 26.3%. In G1, G2 and G3, periportal thickening occurred only in schistosomal patients (8.5%). Mild pathological alterations in patients that cannot yet be detected by clinical examination were detectable in the liver by ultrasound and can be due to fibrosis. The degree of mild periportal fibrosis was diminished in 57.9% of patients 12 months after treatment of schistosomiasis with oxamniquine. At ultrasonography, the mean liver left lobe measurement of G3 was larger than that of G1, and that of G4 larger than that of G1 and G2. The mean size of the spleen of G4 was significantly larger than that of the other three groups, and that of G3 larger than that of G1 and G2.

In vitro maintenance of Angiostrongylus costaricensis does not provide physiological conditions for egg laying

Fifteen pairs (male/female) of Angiostrongylus costaricensis were kept in vitro in Waymouth medium for three days to evaluate the amount and duration of egg laying. At 24, 48 and 72 hours, the mean egg counts were 321, 24 and 4 eggs/10 microliters, respectively. Most of the eggs were eliminated within the first 24 hours, suggesting they are expelled under non-physiological conditions. These results indicate that in vitro conditions are not appropriate for drug trials of egg-laying inhibitors for treatment of abdominal angiostrongylosis.

Gallbladder neuron count in cholelithiasis patients with and without Chagas disease

Various investigators agree that the incidence of cholelithiasis is greater in patients with Chagas disease. The most plausible explanation for this is based on the parasympathetic denervation that occurs over the whole digestive tract due to Chagas disease. In order to analyze the occurrence of this alteration, gallbladder neuron counts were performed on cholelithiasis patients with and without Chagas disease who were being treated at the Department of Digestive Surgery, Universidade Federal do Triângulo Mineiro, Uberaba, Brazil. In the present study, a notable reduction in the number of neurons in the gallbladder wall was observed in Chagas patients, in comparison with non-Chagas subjects.

Gastroenteric virus detection in fecal samples from women in Goiânia, State of Goiás, Brazil

INTRODUCTION: This was a prospective study that included women seen in the obstetrics and gynecology sector of Hospital das Clínicas, Federal University of Goiás, in Goiânia, State of Goiás, with the aim of detecting rotaviruses, adenoviruses, caliciviruses and astroviruses. Eighty-four women participated in the study and from these, 314 fecal samples were collected. Out of all of the women, 29 were seropositive for HIV and 55 were seronegative, and 45 and 39 were pregnant and non-pregnant, respectively. METHODS: Fecal samples were collected from each woman once every two months over the period from July 2006 to June 2007, and they were screened for rotaviruses by means of polyacrylamide gel electrophoresis and immunoenzymatic assays, for caliciviruses and astroviruses by means of RT-PCR and for adenovirus by means of immunoenzymatic assays. The astroviruses were genotyped using nested PCR. RESULTS: Among the 84 patients, 19 (22.6%) were positive for either calicivirus (14/19) or astrovirus (6/19), while one women was positive for both viruses in fecal samples collected on different occasions. Most of the positive samples were collected during the months of July and August (astrovirus) and September and October (calicivirus). None of the samples analyzed was positive for rotavirus or adenovirus. Gastroenteric viruses were detected in 13/19 (68.4%) of the pregnant women, whether HIV-seropositive or not. CONCLUSIONS: The results from the present study showed that neither pregnancy nor HIV-seropositive status among the women increased the risk of infection by any of the gastroenteric viruses studied. This study presents data on gastroenteric virus detection among pregnant and/or HIV-positive women.

Progressive multifocal leukoencephalopathy as an AIDS-defining condition in a patient with high CD4+ T-lymphocyte count

We present the case of a 31-year-old man with acute manifestation of progressive multifocal leukoencephalopathy (PML) as an AIDS-defining disease. The patient presented with a three-day history of neurological disease, brain lesions without mass effect or contrast uptake and a slightly increased protein concentration in cerebrospinal fluid. A serological test for HIV was positive and the CD4+ T-cell count was 427/mm³. Histological examination of the brain tissue revealed abnormalities compatible with PML. The disease progressed despite antiretroviral therapy, and the patient died three months later. PML remains an important cause of morbidity and mortality among HIV-infected patients.

Anti-Toxocara antibodies detected in children attending elementary school in Vitoria, State of Espírito Santo, Brazil: prevalence and associated factors

INTRODUCTION: The aim of this study was to evaluate the frequency of anti-Toxocara antibodies in serum from 7-year-old children attending elementary school in Vitória-ES, Brazil and to correlate these antibodies with socio-demographic factors, the presence of intestinal helminths, blood eosinophil numbers, past history of allergy or asthma, and clinical manifestations of helminth infections. METHODS: The detection of anti-Toxocara antibodies was performed using an ELISA (Cellabs Pty Ltd)on serum from 391 children who had already been examined by fecal examination and blood cell counts. Data from clinical and physical examinations were obtained for all children. RESULTS: The prevalence of anti-Toxocara antibodies was 51.6%, with no gender differences. No significant differences were observed between positive serology and the presence or absence of intestinal worms (60.3 and 51.7%, respectively; p = 0.286). The only variables significantly related to positive serology were onycophagy and the use of unfiltered water. Although eosinophilia (blood eosinophil count higher than 600/mm³) was significantly related to the presence of a positive ELISA result, this significance disappeared when we considered only children without worms or without a past history of allergy or asthma. No clinical symptoms related to Toxocara infection were observed. CONCLUSIONS: There is a high prevalence of anti-Toxocara antibodies in children attending elementary schools in Vitória, which may be partially related to cross-reactivity with intestinal helminths or to a high frequency of infection with a small number of Toxocara eggs.

Use of Poisson spatiotemporal regression models for the Brazilian Amazon Forest: malaria count data

INTRODUCTION: Malaria is a serious problem in the Brazilian Amazon region, and the detection of possible risk factors could be of great interest for public health authorities. The objective of this article was to investigate the association between environmental variables and the yearly registers of malaria in the Amazon region using Bayesian spatiotemporal methods. METHODS: We used Poisson spatiotemporal regression models to analyze the Brazilian Amazon forest malaria count for the period from 1999 to 2008. In this study, we included some covariates that could be important in the yearly prediction of malaria, such as deforestation rate. We obtained the inferences using a Bayesian approach and Markov Chain Monte Carlo (MCMC) methods to simulate samples for the joint posterior distribution of interest. The discrimination of different models was also discussed. RESULTS: The model proposed here suggests that deforestation rate, the number of inhabitants per km², and the human development index (HDI) are important in the prediction of malaria cases. CONCLUSIONS: It is possible to conclude that human development, population growth, deforestation, and their associated ecological alterations are conducive to increasing malaria risk. We conclude that the use of Poisson regression models that capture the spatial and temporal effects under the Bayesian paradigm is a good strategy for modeling malaria counts.

Communal egg laying by Gonatodes humeralis (Sauria, Gekkonidae) in Manaus primary and secondary forest areas

Communal nesting has been registered for a number of lizard species at different sites. Here it is described communal egg laying of Gonatodes humeralis at different sites near and in human buildings in the period between 1990 and 1998. All these communal nests have been found in the dry season, between April and July, suggesting that the nests of are more common in this season, when the activity of their predators is less intense and the reduction of humidity diminish the decomposition action of the fungi that may kill the eggs.

Five egg-laying queens in a single colony of brazilian stingless bees (Melipona scutellaris Latreille

Polygyny, characterized by the presence of several egg-laying queens, is considered as a temporary colony status. In stingless bees it is rarely observed. This paper reports the first case of natural polygyny in Melipona scutellaris colony, with five egg-laying queens.

Contribution to the normal fecal flora of the hamster: Proteus mirabilis in normal feces of hamster

Proteus mirabilis must be considered a normal inhabitant of the intestine of hamsters. It is also found in the vaginal secretion of females of this animal, when in oestrus.

Biotipagem e resistotipagem para o traçado epidemiológico da origem fecal de Klebsiella pneumoniae em infecções urinárias

Em 24 (82,7%) de 29 pacientes com infecção urinária por Klebsiella pneumoniae isolamos a mesma espécie a partir de amostras fecais. Estudamos 24 cepas urinárias e 219 cepas fecais encontrando 50 biótipos distintos (em média quatro biótipos por amostra fecal). Em dez (34,4%) dos 29 pacientes o biótipo de uma ou mais cepas fecais corresponderam ao biotipo da cepa urinária - sem encontrarmos associação entre a simultaneidade e a prévia cateterização vesical (p>0,05). Na resistotipagem - utilizando quatro substâncias químicas previamente escolhidas entre 34 produtos testados (verde brilhante, verde malaquita, telurito de potássio e cloreto mercúrico) encontramos 16 resistotipos distintos. Em 14 (58,3%), dos 24 casos houve detecção do mesmo resistotipo em cepa(s) fecal(is) e urinária do mesmo paciente, entretanto, só em cinco (20,9%) dos casos houve concordância com a biotipagem na indicação de simultaneidade. A concordância de resultados quanto à ausência ou presença de biotipos ou resistotipos simultâneos, na urina e nas fezes, foi de somente 54,2%. A presença de resistência aos íons telurito e mercúrio, entre cepas fecais e cepas urinárias, no mesmo paciente, estava significativamente associada (p<0,001).