A preliminary study of the prevalence of intestinal parasites in immunocompromised patients with and without gastrointestinal manifestations

The objective of the present study was to determine the prevalence of the intestinal parasites most commonly found in immunocompromised patients. A group of 111 individuals with acute lymphoid leukaemia (ALL), chronic myeloid leukaemia (CML), human immunodeficiency virus (HIV) and other immunocompromised conditions (principally haematological disorders) was selected. A battery of tests was performed on each individual to identify the presence of parasites (three stool specimens with saline solution and Lugol both directly and by concentration, culture and special staining). No significant differences were found among the frequencies of the different parasites with the several types of immunocompromised conditions. The overall frequencies of potentially pathogenic and opportunistic parasites were 32.4% (36/111) and 9% (10/111) respectively, the most frequently encountered among the latter being Cryptosporidium sp., Microsporidia spp. and Strongyloides stercoralis.

Blastocystis hominis and other intestinal parasites in a community of Pitanga City, Paraná State, Brazil

The objective was to estimate the prevalence of Blastocystis hominis, to evaluate the effectiveness of different techniques for its diagnosis as well as to estimate the prevalence of other intestinal parasites in the community of Campo Verde, a district of Pitanga. The work was carried out from August to October 2004. Samples of feces from children and adults were collected and submitted to the techniques of direct wet mount, flotation in zinc sulphate solution, tube sedimentation, sedimentation in formalin-ether and staining by Kinyoun and iron hematoxylin methods. From 181 studied individuals, 128 (70.7%) showed protozoa and/or helminths in stool samples. The most prevalent species were Endolimax nana (33.7%); B. hominis (26.5%); Giardia lamblia (18.2%); Entamoeba coli (17.1%); Ascaris lumbricoides (16.6%); Iodamoeba bütschlii (9.4%); and ancylostomatidae (7.7%). B. hominis was only identified by the techniques of direct wet mount, sedimentation in formalin-ether and staining by iron hematoxylin, though the latter was less sensitive than the other methods. The high frequency of B. hominis demonstrated by this study indicates the need to include laboratory techniques that enable identification of the parasite on a routine basis.

Mass treatment for intestinal helminthisis control in an Amazonian endemic area in Brazil

The objective of the present study was to estimate the prevalence of soil-transmitted helminthiasis and evaluate the sanitary conditions and the role of a mass treatment campaign for control of these infections in Santa Isabel do Rio Negro. A cross-sectional survey was carried out in 2002, to obtain data related to the sanitary conditions of the population and fecal samples for parasitological examination in 308 individuals, followed by a mass treatment with albendazole or mebendazole with coverage of 83% of the city population in 2003. A new survey was carried out in 2004, involving 214 individuals, for comparison of the prevalences of intestinal parasitosis before and after the mass treatment. The prevalences of ascariasis, trichuriasis and hookworm infection were 48%; 27% and 21% respectively in 2002. There was a significant decrease for the frequency of infections by Ascaris lumbricoides (p < 0.05; OR / 95% CI = 0.44 / 0.30 - 0.65), Trichuris trichiura (p < 0.05; OR / 95% CI = 0.37 / 0.22 - 0.62), hookworm (p < 0.05; OR / 95% CI = 0.03 / 0.01 - 0.15) and helminth poliparasitism (p < 0.05; OR / 95% CI = 0.16 / 0.08 - 0.32). It was also noticed a decrease of prevalence of infection by Entamoeba histolytica / dispar (p < 0.05; OR / 95% CI = 0.30 / 0.19 - 0.49) and non-pathogenic amoebas. It was inferred that a mass treatment can contribute to the control of soil-transmitted helminthiasis as a practicable short-dated measure. However, governmental plans for public health, education and urban infrastructure are essential for the sustained reduction of prevalences of those infections.

Comparison of serology, antigenemia assay and the polymerase chain reaction for monitoring active cytomegalovirus infections in hematopoietic stem cell transplantation patients

Forty-six allogeneic hematopoietic stem cell transplantation (HSCT) patients were monitored for the presence of CMV antibodies, CMV-DNA and CMV antigens after transplantation. Immunoenzymatic serological tests were used to detect IgM and the increase in CMV IgG antibodies (increase IgG), a nested polymerase chain reaction (N-PCR) was used to detect CMV-DNA, and an antigenemia assay (AGM) was used to detect CMV antigens. The presence of CMV-IgM and/or CMV-increase IgG antibodies was detected in 12/46 (26.1%) patients, with a median time between HSCT and the detection of positive serology of 81.5 days. A positive AGM was detected in 24/46 (52.2%) patients, with a median time between HSCT and antigen detection of 62 days. Two or more consecutive positive N-PCR results were detected in 32/46 (69.5%) patients, with a median time between HSCT and the first positive PCR of 50.5 days. These results confirmed that AGM and mainly PCR are superior to serology for the early diagnosis of CMV infection. Six patients had CMV-IgM and/or CMV-increase IgG with a negative AGM (five cases) or N-PCR assay (one case). In five of these cases the serological markers were detected during the first 100 days after HSCT, the period of highest risk. These findings support the idea that serology may be useful for monitoring CMV infections in HSCT patients, especially when PCR is unavailable.

Survival of Trypanosoma cruzi in sugar cane used to prepare juice

Chagas disease can be transmitted to man by many different means, including contact with infected triatomine feces, blood transfusion, laboratory accidents, organ transplants, and congenital or oral routes. The latter mode has received considerable attention recently. In this assay, we evaluate the survival of Trypanosoma cruzi contaminating sugar cane used to prepare juice, as well as the viability and capacity for infection by the parasite after recovery. Thirty triatomines were contaminated with T. cruzi Y strain and 45 days later pieces of sugar cane were contaminated with the intestinal contents of the insects. The pieces were ground at different intervals after contamination (time = 0, 1, 4, 6, 12 and 24 hours) and the juice extracted and analyzed. Different methods were used to show T. cruzi in the juice: direct analysis, hematocrit tube centrifugation and QBC, and experimental inoculation in 47 female BALB/c mice (five control mice and seven mice for each interval examined (five inoculated orally and two intraperitoneally). Positive results were found using the direct analysis and QBC methods for juice prepared up to 12 hours after initial contamination. However, by the centrifugation technique, positivity was found only up to four hours after contamination of the sugar cane. Inoculated animals showed parasitemia during a 14 day observation period, demonstrating the high survival rate of T. cruzi in sugar cane.

Serodiagnosis of neurocysticercosis in patients with epileptic seizure using ELISA and immunoblot assay

Sera from 88 patients from Santa Catarina and São Paulo states of Brazil, with epileptic seizures who underwent cerebral computed tomography (CT) were analyzed for the detection of antibodies to T. solium cysticercus by ELISA and Immunoblot (IB) with the following antigens: Taenia solium cysticercus total saline (Tso), Taenia crassiceps cysticercus vesicular fluid (Tcra-vf) and T. crassiceps cysticercus glycoproteins (Tcra-gp). ELISA carried out with Tso, Tcra-vf and Tcra-gp antigens showed 95%, 90% and 80% sensitivities, respectively, and 68%, 85% and 93% specificities, respectively. In the epileptic patients group, ELISA positivity was 30%, 51% and 35% with Tso, Tcra-vf and Tcra-gp antigens respectively. Considering the IB as the confirmatory test, the positivity was 16% (14/88) in the epileptic patients total group and 22% (12/54) in the epileptic patients with positive CT and signals of cysticercosis. We found a significant statistical correlation among ELISA or IB results and the phase of the disease when any antigens were used (p < 0.05). We emphasize the need to introduce in the laboratory routine the search for neurocysticercosis (NC) in patients presenting with epileptic seizures because of the high risk of acquiring NC in our region and its potential cause of epilepsy.

Giardia lamblia and other intestinal parasitic infections and their relationships with nutritional status in children in Brazilian Amazon

The objective of this survey was to assess the relationships between intestinal parasitism, nutritional status and hemoglobin level in children with Indian ascendancy living in an urban area in Brazilian Amazon. We carried out a cross-sectional survey obtaining anthropometric, parasitological and socioeconomic data, and hemoglobin measurements of children aged six to 84 months. Anthropometric data were expressed as z-scores for weight for age (WAZ), height for age (HAZ), weight for height (WHZ) and mid upper circumference for age (MUACZ) parameters. Parasitological examinations were performed through Ritchie (n = 307), Kato-Katz (n = 278), Baermann-Moraes (n = 238) and Safranin-methylene blue methods (n = 307). Hemoglobin measurements were obtained with a Hemocue® photometer (n = 282). Socioeconomic data were used in order to classify children in three family income strata (n = 242). Multiple linear regression analysis showed independent interactions between Giardia lamblia and WAZ (beta = -0.195, SE = 0.138, p = 0.003), WHZ (beta = -0.161, SE = 0.133, p = 0.018) and MUACZ (beta = -0.197, SE = 0.143, p = 0.011), controlling for age, sex, family income, Ascaris lumbricoides, and hookworm infection. Also, the multivariate model showed that the only variable associated with hemoglobin levels was age. Intestinal parasitism control should increase children's possibilities of full development in the studied area.

Intestinal parasitoses and environmental factors in a rural population of Argentina, 2002-2003

We evaluate the prevalence of intestinal parasites in 504 people and the degree of association between environmental variables and parasites found in population, soil and water in a rural area of Argentina during 2002-2003. A structured survey was used to evaluate the environmental variables and fecal-human, soil and water samples were analyzed. The prevalence of parasites was 45.4%. Most prevalent protozoa were Blastocystis hominis (27.2%) and Giardia lamblia (6.9%), while the most prevalent helminth was Ascaris lumbricoides (3.8%). The analyzed environmental variables showing association (p < 0.05) with presence of parasites in population were: cardboard-tin or wooden house, dirt floor, home or communal water pump, faucet outside the house or public faucet and cesspool or latrine. Parasite forms were found in 82.3% of the soil samples and in 84.2% of the water samples. In both samples we found parasites that were also found in people. In this study we have found deficient sanitary conditions associated with presence of parasites in population and we have evidenced that contaminated soil and water were the source of these parasites.

Prevalence of intestinal microsporidiosis in Human Immunodeficiency Virus-infected patients with diarrhea in major United States cities

To determine the prevalence of intestinal microsporidiosis in HIV-infected patients, we performed a prospective study of HIV-infected patients with diarrheal illnesses in three US hospitals and examined an observational database of HIV-infected patients in 10 US cities. Among 737 specimens from the three hospitals, results were positive for 11 (prevalence 1.5%); seven (64%) acquired HIV through male-to-male sexual contact, two (18%) through male-to-male sexual contact and injection drug use, and one (9%) through heterosexual contact; one (9%) had an undetermined mode of transmission. Median CD4 count within six months of diagnosis of microsporidiosis was 33 cells/µL (range 3 to 319 cells/µL). For the national observational database (n = 24,098), the overall prevalence of microsporidiosis was 0.16%. Prevalence of microsporidiosis among HIV-infected patients with diarrheal disease is low, and microsporidiosis is most often diagnosed in patients with very low CD4+ cell counts. Testing for microsporidia appears to be indicated, especially for patients with very low CD4+ cell counts.

Prevalence of intestinal parasites in children from public daycare centers in the city of Belo Horizonte, Minas Gerais, Brazil

The objective of this study was to verify the occurrence of intestinal parasites in 3 to 6-year-old children from daycare centers maintained by the municipal government of Belo Horizonte, Minas Gerais, Brazil. Coproparasitological tests performed in 472 children have shown that 24.6% of them had some type of parasites, 6.6% of the children having more than one type. Among protozoa, Entamoeba coli (14.0%) and G. duodenalis (9.5%) were the most prevalent, whereas Ascaris lumbricoides (3.0%) and Trichuris trichiura (1.1%) were the most frequent among the helminths. Thus, we can observe that intestinal parasites still represent a serious public health problem in Belo Horizonte, especially among children and in areas where the socioeconomic conditions are less favorable.

Molecular characterization of two rocio flavivirus strains isolated during the encephalitis epidemic in são paulo state, brazil and the development of a one-step rt-pcr assay for diagnosis

Rocio virus (ROCV) was responsible for an explosive encephalitis epidemic in the 1970s affecting about 1,000 residents of 20 coastland counties in São Paulo State, Brazil. ROCV was first isolated in 1975 from the cerebellum of a fatal human case of encephalitis. Clinical manifestations of the illness are similar to those described for St. Louis encephalitis. ROCV shows intense antigenic cross-reactivity with Japanese encephalitis complex (JEC) viruses, particularly with Ilheus (ILHV), St. Louis encephalitis, Murray Valley and West Nile viruses. In this study, we report a specific RT-PCR assay for ROCV diagnosis and the molecular characterization of the SPAn37630 and SPH37623 strains. Partial nucleotide sequences of NS5 and E genes determined from both strains were used in phylogenetic analysis. The results indicated that these strains are closely related to JEC viruses, but forming a distinct subclade together with ILHV, in accordance with results recently reported by Medeiros et al. (2007).

Prevalence of intestinal parasites in a population in south of Tehran, Iran

The aim of this study was to describe epidemiologic characteristics of intestinal parasites in a population in south of Tehran, Iran. A retrospective cross-sectional study of patients with suspicious intestinal parasitic infections referred to the Zakaria Razi Laboratory in Shahre-Ray, southern Tehran, Iran, was conducted from April 21, 2004 to October 20, 2005. All stool samples were examined and socio-demographic informations were retrieved. Of 4,371 referred patients, 466 (239 males and 227 females) were laboratory diagnosed with intestinal parasites, with a period prevalence of 10.7%. Blastocystis hominis (B. hominis) and Giardia lamblia (G. lamblia) were the most frequent intestinal parasites. More than half of patients aged ³ 18 years had a low level of educational attainment (e.g. illiterate, primary school, high school) (170/331, 54.1%). Further, majority of patients were homemakers (42.3%, 140/331) or workers (28.1%, 93/331) employed in various business settings such as food industry and construction. Findings of this study showed that intestinal parasitic infections are still a major public health challenge in Iran that needs to be addressed. We believe that public education, improving sanitation conditions of underdeveloped areas/communities, community involvement, and supporting evidence-based practice/programs are the major keys to success in preventing the spread of intestinal parasitic infections in Iran.

Necrose Intestinal na Criança

O termo necrose intestinal traduz exclusivamente um conceito anatomopatológico e clínco, e implica sempre um isquémia instestinal oclusiva ou não. A enterocolite necrosante, em sentido lato, implica uma isquémia intestinal não oclusiva associada a um mecanismo infeccioso. O factor desencadeante da necrose é, por vezes, difícil de determinar. A enterocolite necrosante ocorre em 90% dos casos em recém-nascidos prematuros, sendo mesmo frequente no recém-nascido de termo e rara na crança mais velha e no adulto. Apresentam-se os casos clínicos de duas crianças; uma de sete anos com antecedentes de neutropénia crónica e outra de onze anos com défice cognitivo grave, dismorfia e alterações de comportamento, ambas internadas por quadro de abdómen agudo e choque. Foi efectuada ressecção do segmento jejunal num dos casos e ressecção subtotal do cólon no outro, por necrose. Apesar da cirurgia e da terapêutica médica de suporte, ambas acabaram por morrer em falência multiorgânica, respectivamente três horas após a cirurgia e ao 14º dia de internamento, após segunda intervenção com ressecção do segmento necrosado íleon. A necrópsia de ambos os casos revelou necrose extensa de todo o restante intestino. Os dois casos clínicos comportaram-se como enterocolite necrosante da criança, sendo o diagnóstico de exclusão numa delas, de enterocolite neutropénica. Efectua-se uma revisão dos mecanismos etiopatogénicos da necrose intestinal da criança, desde os tromboembólicos, obstrutivos extrínsecos ou endoluminais, inflamatórios, isquémicos não oclusivos, até aos infecciosos. Para além das medidas gerais de terapêutica, salienta-se a necessidade de uma intervenção cirúrgica precose e de meios diagnósticos terapêuticos, como o doseamento, no sangue e na urina, da proteína de ligação aos ácidos gordos intestinais e a arteriografia selectiva.