Intestinal protozoa and helminths among Terena Indians in the State of Mato Grosso do Sul: high prevalence of Blastocystis hominis

A parasitological survey was carried out among Terena Indians living in the Tereré settlement in the municipality of Sidrolândia, State of Mato Grosso do Sul, Brazil. Single samples of feces from 313 Indians were processed by means of the spontaneous sedimentation method. In the population studied, 73.5% were infected with at least one intestinal parasite or commensal. Protozoa predominated. Blastocystis hominis (40.9%), Entamoeba coli (33.2%) and Entamoeba histolytica/Entamoeba dispar (31.6%) were the most common. Bivariate analysis showed that females were generally more infected and presented higher rates of infection by Entamoeba histolytica/Entamoeba dispar and Entamoeba coli. Males were more infected by hookworms and Strongyloides stercoralis than females. The precarious sanitary conditions of the Tereré settlement are probably a contributory factor towards the high prevalence of intestinal protozoa.

Preliminary observations on fluids incubated with Wuchereria bancrofti using the immunochromatographic test

To assess the performance of the immunochromatographic test for filariasis, adult Wuchereria bancrofti worms were incubated under different conditions. The tests were strongly positive with incubation fluids from both living and mechanically damaged females. Negative results were observed with incubation fluids from all male worms and from intact dead females.

Causas de óbito em pacientes com síndrome da imunodeficiência adquirida, necropsiados na Fundação de Medicina Tropical do Amazonas

O objetivo deste estudo foi verificar em 129 pacientes com AIDS, necropsiados na Fundação de Medicina Tropical do Amazonas de 1996 a 2003, as causas do óbito, observando o grau de concordância entre os diagnósticos necroscópicos com os diagnósticos clínicos. A doença mais freqüente que causou o óbito foi tuberculose 28%, seguida de pneumonia bacteriana 17%, histoplasmose 13%, toxoplasmose 10%, pneumocistose 8%, criptococose 5%, sepse bacteriana 4% e 15% outras causas. A concordância entre o diagnóstico clínico antemortem e a necropsia foi de 51,9%. O principal órgão acometido foi o pulmão 82,2%. O tempo de sobrevivência após o diagnóstico laboratorial até o óbito variou entre um mês e 120 meses. A média de sobrevivência foi 15 dias e 56% morreram menos de um mês após o diagnóstico, 15 pacientes morreram na mesma data do diagnóstico. Esses resultados demonstram a importância da necropsia na causa mortis em pacientes com AIDS.

Pulmonary changes during acute experimental murine manson schistosomiasis

Dry cough, dyspnea and manifestations of bronchial asthma have recently been observed in patients with acute schistosomiasis. To investigate the type and pathogenesis of these conditions, an experimental mouse model for acute schistosomiasis was used. Forty mice were divided into four groups of ten each: three infected groups and a non-infected control group. The animals were examined 7, 28-35 and 40 days after exposure to cercariae. During the acute phase of the infection (28-35 days), a process of multifocal interstitial pneumonitis involving the peribronchial, peribronchiolar and subpleural tissues was found. This process was not seen during the other phases of the infection. Indirect immunofluorescence failed to demonstrate the presence of schistosomal antigens in the acute-phase lesions. The pneumonitis was attributed to products (inflammatory mediators) from acute-phase periovular necrotic-inflammatory lesions in the liver that were transported to the lungs by the bloodstream.

Prevalence of hepatitis A virus infection: the paradoxical example of isolated communities in the western Brazilian Amazon region

This study evaluated the prevalence of hepatitis A virus infection in the rural area of Lábrea, in the western Brazilian Amazon region. Communities and households were selected randomly. Serum samples were analyzed by means of the immunoenzymatic method for the presence of total antibodies against HAV. The study included 1,499 individuals. The prevalence of anti-HAV was 74.6% (95% CI 72.3-76.8). Univariate analysis showed associations with age (chi-square for linear trend = 496.003, p < 0.001), presence of outside toilet (p < 0.001), history of hepatitis (p < 0.001) and family history of hepatitis (p = 0.05). After adjusting for age, HAV infection also showed an association with the number of people in the family (p = 0.03). The overall prevalence rates were high, but not more than 60% of the children under the age of ten years had already been infected. Very high prevalence was detected only within older cohorts, thus paradoxically defining this as a region with intermediate endemicity, even under the conditions of poverty encountered.

Boosting the suppressive effects of Ascaris suum components in IFN-γ-deficient mice

High molecular weight components from Ascaris suum extract suppress ovalbumin-specific immunity in mice. In IFN-γ-deficient mice, ovalbumin-specific delayed-type hypersensitivity reactions are more strongly downregulated by these suppressive components. Here, the cellularity of the delayed-type hypersensitivity reaction in IFN-γ-deficient mice and the increased downregulation induced by Ascaris suum components were analyzed. IL-12p40-dependent neutrophilic influx was predominant. Suboptimal doses of the suppressive fraction from this nematode completely inhibited the hypersensitivity reaction, thus indicating intensification of the immunosuppression under conditions of intense recruitment of IFN-γ-independent neutrophils.

Visceral leishmaniasis in Rio de Janeiro, Brazil: eco-epidemiological aspects and control

From 1977 (index case) to 2006, 87 cases of visceral leishmaniasis were confirmed in the municipality of Rio de Janeiro, Brazil, in periurban areas on the continental and coastal slopes of the Pedra Branca massif and the continental slopes of the Gericinó massif. The majority (65.5%) of the patients were more than five years old, predominantly males (61.5%), but without any difference between the sexes below the age of 14 years. The overall fatality rate was 10.4%. Two cases of visceral leishmaniasis/human immunodeficiency virus coinfection were detected. Leishmania chagasi was isolated from human and canine cases. The associations between the presence of phlebotomines and human and canine migrations, disorderly occupation involving degradation of environmental preservation areas and poor socioeconomic conditions may have created a favorable setting for the establishment and propagation of the disease. Close epidemiological surveillance associated with traditional control measures and others (active case researches, land clearing and health education), reduced the incidence of human cases from 2.8 per 100,000 inhabitants in 1981 to less than 0.01 per 100,000 since 1997. The canine infection rates decreased from 4.6% in 1984 to 1.6% in 2008. Lutzomyia longipalpis was not detected in some locations where human and canine cases occurred. In the years 2007 and 2008, no new human cases were reported, but there is a persistent and worrisome residual canine seroprevalence.

Evaluation of the histopathological hepatic lesions and opportunistic agents in Brazilian HIV patients

INTRODUCTION: to evaluated the type histopathological hepatic lesions and opportunistic agents in Brazilian HIV-infected patients. METHODS: we examined 52 percutaneous liver biopsies of 50 HIV-infected patients who had at least two of the following conditions: fever of unknown origin, unexplained severe emaciation, hepatomegaly or abnormal liver chemistry. The specimens were cultured for mycobacteria and fungi and stained by standard procedures. RESULTS: reactive patterns, granulomatous hepatitis and chronic active hepatitis were verified in 28 (54%), 11 (21%) and 8 (15%) of the patients respectively. Opportunistic infections were diagnosed in 18 (36%) patients: mycobacteria in 12 (24%), Cryptococcus neoformans in 5 (10%) patients and mycobacteria and yeast was isolated from the same liver fragment in one patient. CONCLUSIONS: mycobacteriosis was the most common opportunistic infection and liver tissue culture is an important method to detect opportunistic agents, even in the absence of histological lesions.

Injuries and envenoming by aquatic animals in fishermen of Coxim and Corumbá municipalities, state of Mato Grosso do Sul, Brazil: identification of the causative agents, clinical aspects and first aid measures

INTRODUCTION: The fishes of continental Brazil have socioeconomic importance due to their potential for sport fishing and commercial and subsistence uses, as seen in the Upper Paraguay River Basin, particularly in the municipalities of the Pantanal region, where it is the second largest economic activity. Injuries caused in professional fishermen are common and poorly studied, as in other regions of the country. METHODS: Data were obtained from questionnaires and interviews with 100 professional fishermen, 50 in each municipality, between December 2008 and October 2009. RESULTS: All the fishermen reported some kind of injury caused by fish stings (78% of injuries) and fish, alligator and snake bites (22%) on the hands (46% of cases) and feet (35% of cases). Most of the patients had mild symptoms. The most severe cases were associated with secondary bacterial infections and required specific treatment and prolonged recovery associated with social and economic losses. CONCLUSIONS: The results of this study indicate that the stressful work conditions, inattention to basic preventive measures and carelessness were factors that contributed to accidents and that the toxicity and ability to inflict mechanical trauma of some aquatic species, plus the ineffective use of first aid and hospital treatment, contributed to the high morbidity and complications in many cases. Data from this study are relevant to the fishing communities of the Pantanal region, since they reveal high rates of accidents, lack of knowledge concerning first aid, initial treatment, injury prevention and lack of medical follow-up of the population.

Concurrent dengue and malaria in the Amazon region

INTRODUCTION: The Amazon region has extensive forested areas and natural ecosystems, providing favorable conditions for the existence of innumerous arboviruses. Over 200 arboviruses have been isolated in Brazil and about 40 are associated with human disease. Four out of 40 are considered to be of public health importance in Brazil: Dengue viruses (1-4), Oropouche, Mayaro and Yellow Fever. Along with these viruses, about 98% of the malaria cases are restricted to the Legal Amazon region. METHODS: This study aimed to investigate the presence of arboviruses in 111 clinical serum samples from patients living in Novo Repartimento (Pará), Plácido de Castro (Acre), Porto Velho (Rondônia) and Oiapoque (Amapá). The viral RNA was extracted and RT-PCR was performed followed by a Multiplex-Nested-PCR, using Flavivirus, Alphavirus and Orthobunyavirus generic and species-specific primers. RESULTS: Dengue virus serotype 2 was detected in two patients living in Novo Repartimento (Pará) that also presented active Plasmodium vivax infection. CONCLUSIONS: Despite scant data, this situation is likely to occur more frequently than detected in the Amazon region. Finally, it is important to remember that both diseases have similar clinical findings, thus the diagnosis could be made concomitantly for dengue and malaria in patients living or returning from areas where both diseases are endemic or during dengue outbreaks.

Prevalence of intestinal parasites in preschool children in the region of Uberlândia, State of Minas Gerais, Brazil

INTRODUCTION: Children are an important high-risk group for helminth and protozoa infections. Daycare centers are environments where children have proven to be more susceptible to acquiring intestinal parasites. Thus, the purpose of this study was to verify the prevalence of intestinal parasites in children who attended the two daycare centers maintained by the local government of Uberlândia, State of Minas Gerais, Brazil. METHODS: Fecal samples were collected from 133 children (73 children at the Public Preschool for Early Childhood Education, PPECE A, and 60 at the PPECE B) following identification according to sex and age and agreement to participate by parents or guardians who signed the free, informed consent form. The samples were examined by the Lutz method. RESULTS: Coproparasitological tests performed on 133 children showed that 29.3% of them were parasitized for enteroparasites or commensals, 6.7% of the children presented polyparasitism. Among the protozoa, Giardia lamblia were the most prevalent and Hymenolepis nana were the most frequent among the helminths. CONCLUSIONS: Thus, analysis of the results showed that intestinal parasites still represent a public health problem, especially among children and in areas where the socioeconomic and educational conditions are less favorable.

Prevalence of cholelithiasis in patients with chagasic megaesophagus

INTRODUCTION: The prevalence of cholelithiasis in the general population ranges from 9 to 18%. This prevalence is known to be higher in the presence of parasympathetic nerve damage of the biliary tract either due to surgery (vagotomy) or neuronal destruction (Chagas disease). The objective of this study was to evaluate the association of cholelithiasis and chagasic or idiopathic megaesophagus. METHODS: The ultrasound scans of 152 patients with megaesophagus submitted to cardiomyotomy and subtotal esophagectomy surgery were evaluated. The presence of cholelithiasis was compared between chagasic and idiopathic esophagopathy and ultrasound and clinical findings were correlated with age, sex and race. RESULTS: A total of 152 cases of megaesophagus, including 137 with chagasic megaesophagus and 15 with idiopathic megaesophagus, were analyzed. The mean age was 56.7 years (45-67) in the 137 patients with chagasic megaesophagus and 35.6 years (27-44) in the 15 cases of idiopathic megaesophagus, with a significant difference between the two groups (p < 0.0001). The group with chagasic megaesophagus consisted of 59 (43%) women and 78 (56.9%) men, while the group with idiopathic megaesophagus consisted of 8 (53.3%) women and 7 (46.6%) men, showing no significant difference between the groups. Of the 137 patients with confirmed chagasic megaesophagus, 39 (28.4%) presented cholelithiasis versus one case (6.6%) in the 15 patients with idiopathic megaesophagus. CONCLUSIONS: The prevalence of cholelithiasis is high in patients with chagasic megaesophagus and preoperative ultrasound should be performed routinely in these patients in order to treat both conditions during the same surgical procedure.