High prevalence of enteroparasitosis in urban slums of Belo Horizonte-Brazil. Presence of enteroparasites as a risk factor in the family group.

The present study evaluates the prevalence of enteroparasitosis in the urban slums of Belo Horizonte, Brazil and the risk of transmitting enteroparasites to the family members of infected individuals. Stool samples were collected and examined at clinical laboratories near each slum. Individuals were identified and classified as positive for parasitosis (IP(+)), and individuals with negative stool tests were classified as negative for parasitosis (IP(-)) and enrolled as control patients. We collected samples from 594 patients, of which 20·2% and 79·8% were classified as IP(+) and IP(-), respectively. In addition, 744 family members (FIPs) effectively participated in the study by providing fecal samples. In total, 1338 participants were evaluated. Of these, 34·6% were tested positive for parasitosis. Blastocystis was the most prevalent parasite, infecting 22·4% of individuals. Among FIPs, the overall prevalence was 46·1%. Of these, 50·6% and 44·7% were classified as FIPs(+) and FIPs(-), respectively. These results showed that IP(+) did not impact the prevalence of infection within the studied communities, not constituting index cases of specific risk behaviors, suggesting that, in fact, these communities are exposed to similar oral-fecal routes of contamination.

Prevalence of intestinal parasitism and associated symptomatology among hemodialysis patients.

Intestinal parasites are an important cause of morbidity and mortality. Immunocompromised individuals may develop more severe forms of these infections. Taking into account the immunity impairment in patients suffering from chronic renal failure (CRF), we will determine the prevalence and associated symptoms of intestinal parasites in these patients. Controls without CRF were used for comparison. Stool samples were collected and processed for microscopic identification of parasites using the Formalin-ether concentration method. For Cryptosporidium diagnosis, the ELISA technique was used. One hundred and ten fecal samples from hemodialysis patients were analyzed, as well as 86 from a community group used as control group. A result of 51.6% of intestinal parasites was observed in hemodialysis patients and 61.6% in the control group. Cryptosporidium and Blastocystis were the most common infections in patients with CRF (26.4% and 24.5%, respectively). Blastocystis was the most common infection in the control group (41.9%), however no individual was found positive for Cryptosporidium. Among the CRF patients, 73.6% were symptomatic, 54.3% of these tested positive for at least one parasite, in contrast to 44.8% in asymptomatic patients (p = 0.38). The most common symptoms in this group were flatulence (36.4%), asthenia (30.0%) and weight loss (30.0%). In the control group, 91.9% were symptomatic, 60.8% of these tested positive for at least one parasite, in contrast to 71.4% in asymptomatic patients (p = 0.703). A significant difference between the two groups was observed with regard to symptoms, with bloating, postprandial fullness, and abdominal pain being more frequent in the control group than in the hemodialysis group (all p < 0.05). Comparing symptomatic with asymptomatic, there was no association in either group between symptoms or the prevalence of parasitic infection, nor with the type of parasite or with multiple parasitic infections. Patients with chronic renal failure are frequent targets for renal transplantation, which as well as the inherent immunological impairment of the disease itself, results in immunosuppression by medication. For this reason, carriers of intestinal parasites with pathogenic potential can develop serious clinical complications influencing the success of transplantation. This fact, coupled with the high prevalence of intestinal parasites and the dissociation between symptoms and infection in CRF patients, suggests that the stool test should be incorporated in routine propedeutics. Furthermore, preventive measures for the acquisition of parasites through the fecal-oral contamination route should be introduced.

Prevalence of ittestinal parasitism and associated symptomatology among hemodialysis patients / Prevalência de parasitismo intestinal e sintomatologia associada em pacientes hemodialíticos

Intestinal parasites are an important cause of morbidity and mortality. Immunocompromised individuals may develop more severe forms of these infections. Taking into account the immunity impairment in patients suffering from chronic renal failure (CRF), we will determine the prevalence and associated symptoms of intestinal parasites in these patients. Controls without CRF were used for comparison. Stool samples were collected and processed for microscopic identification of parasites using the Formalin-ether concentration method. For Cryptosporidium diagnosis, the ELISA technique was used. One hundred and ten fecal samples from hemodialysis patients were analyzed, as well as 86 from a community group used as control group. A result of 51.6% of intestinal parasites was observed in hemodialysis patients and 61.6% in the control group. Cryptosporidium and Blastocystis were the most common infections in patients with CRF (26.4% and 24.5%, respectively). Blastocystis was the most common infection in the control group (41.9%), however no individual was found positive for Cryptosporidium. Among the CRF patients, 73.6% were symptomatic, 54.3% of these tested positive for at least one parasite, in contrast to 44.8% in asymptomatic patients (p = 0.38). The most common symptoms in this group were flatulence (36.4%), asthenia (30.0%) and weight loss (30.0%). In the control group, 91.9% were symptomatic, 60.8% of these tested positive for at least one parasite, in contrast to 71.4% in asymptomatic patients (p = 0.703). A significant difference between the two groups was observed with regard to symptoms, with bloating, postprandial fullness, and abdominal pain being more frequent in the control group than in the hemodialysis group (all p < 0.05). Comparing symptomatic with asymptomatic, there was no association in either group between symptoms or the prevalence of parasitic infection, nor with the type of parasite or with multiple parasitic infections. Patients with chronic renal failure are frequent targets for renal transplantation, which as well as the inherent immunological impairment of the disease itself, results in immunosuppression by medication. For this reason, carriers of intestinal parasites with pathogenic potential can develop serious clinical complications influencing the success of transplantation. This fact, coupled with the high prevalence of intestinal parasites and the dissociation between symptoms and infection in CRF patients, suggests that the stool test should be incorporated in routine propedeutics. Furthermore, preventive measures for the acquisition of parasites through the fecal-oral contamination route should be introduced.

Doenças parasitárias infectam grande número de indivíduos em todo o mundo. Manifestações clínicas mais severas podem se apresentar em pacientes imunocomprometidos. Considerando o importante comprometimento imunológico observado em pacientes com insuficiência renal crônica (IRC), foi determinada a prevalência e sintomas associados a parasitoses intestinais nesses pacientes em comparação a controles saudáveis. Foram coletadas amostras fecais de cada participante e processadas para identificação microscópica dos parasitas pelo método de concentração por formol-éter. Foi utilizada a técnica de ELISA para identificar coproantígenos de Cryptosporidium. Foram analisadas 110 amostras fecais de pacientes em hemodiálise e 86 de um grupo controle comunitário. Cryptosporidium e Blastocystis foram as infecções mais freqüentes nos pacientes em hemodiálise (26,4% e 24,5%, respectivamente). Blastocystis foi a infecção mais freqüente no grupo controle (41,9%), entretanto nenhum indivíduo positivo para Cryptosporidium foi identificado. Considerando os pacientes com IRC, 73,6% eram sintomáticos, sendo 54,3% positivos para algum parasita, contra 44,8% nos assintomáticos (p = 0,38). Os sintomas mais frequentes neste grupo foram flatulência (36,4%), adinamia (30,0%) e perda de peso (30,0%). No grupo controle, 91,9% eram sintomáticos, sendo 60,8% positivos para algum parasita, contra 71,4% nos assintomáticos (p = 0,703). Em relação aos sintomas, houve diferença significativa entre os dois grupos, sendo que flatulência, plenitude pós-prandial, e dor abdominal foram mais freqüentes no grupo controle que nos pacientes em hemodiálise (todos p < 0,05). Comparando-se sintomáticos com assintomáticos, não houve associação entre a sintomatologia e a prevalência de parasitose, nem com o tipo de parasita, e nem com o poliparasitismo, nos dois grupos. Considerando que pacientes com IRC são frequentes alvos de transplante renal, resultando em imunossupressão por medicamentos, que é somada à deficiência imunológica inerente à própria doença. Os portadores de parasitas intestinais com potencial patogênico podem desenvolver sérias complicações clínicas que influenciam o sucesso do transplante. Este fato, aliado a alta prevalência de parasitas intestinais e dissociação entre os sintomas e infecção nesses pacientes, sugerem a incorporação do exame de fezes na propedêutica de rotina dos mesmos, juntamente com medidas preventivas para a aquisição de parasitas com rota de contaminação fecal-oral.

Impact of protein malnutrition on histological parameters of experimentally infected animals with Giardia lamblia.

Giardiasis is one of the most common parasitic diseases worldwide, and the disease is an important cause of diarrhoea and malabsorption in children and immunosuppressed individuals. However, there is no evidence that characterises malnutrition as an aggravating factor for this disease. We evaluated changes in villi structures to examine the association between malnutrition and Giardia lamblia infection. We used 32 gerbils, divided into 4 groups: Control (CT) and Control Infected (CTIn), which each received a 20% protein diet, Malnourished (MN) and Malnourished Infected (MNIn), which each received a 5% protein diet. Groups CTIn and MNIn were inoculated with 1×10(6) trophozoites of G. lamblia, while the remaining groups were mock infected. Seven days post-infection, all groups were sacrificed, and the proximal portions of the small intestines were collected for the analysis of villus height, mucus area and extent of Giardia infection. Gerbils fed with a low-protein diet had significantly lower body weights. Malnourished infected animals presented significantly increased production of mucus, suggesting a synergism occurs between malnutrition and Giardiasis, potentially to control the adhesion of Giardia in the mucosa. Villus height was significantly lower in group MNIn compared to CTIn. This work suggests that malnutrition contributes to severity of Giardiasis by decreasing the intestinal absorption capacity via shortening of the villi.

The old and new therapeutic approaches to the treatment of giardiasis: where are we?

Giardia lamblia is the causative agent of giardiasis, one of the most common parasitic infections of the human intestinal tract. This disease most frequently affects children causing abdominal pain, nausea, vomiting, acute or chronic diarrhea, and malabsorption syndrome. In undernourished children, giardiasis is a determining factor in retarded physical and mental development. Antigiardial chemotherapy focuses on the trophozoite stage. Metronidazole and other nitroimidazoles have been used for decades as the therapy of choice against giardiasis. In recent years many other drugs have been proposed for the treatment of giardiasis. Therefore, several synthetic and natural substances have been tested in search of new giardicidal compounds. This study is a review of drugs used in in vitro and in vivo tests, and also drugs tested in clinical trials (nonrandomized and randomized).