Gelatin particle indirect agglutination test for serodiagnosis of schistosomiasis: comparative study with enzyme-linked immunosorbent assay

A new serological test, the gelatin particle agglutination test (GPAT), was used for the serodiagnosis of schistosomiasis mansoni. This technique showed the sensitivity (90.6%) and specificity (97.8%) close to those of enzyme-linked immunosorbent assay. The GPAT can be easily and rapidly performed without specialized equipment, by using lyophilized antigen-coated gelatin particles. The test also seems to be useful for mass screening of Schistosoma infection in field conditions.

Radioactivity studies in Porto urban area: gamma radiation of Paranhos sector

A set of radiation measurements were carried out in several public and private institutions. These were selected with basis on the people affluence and passage to these sites. These measurements were registration formed either indoor, outdoor or underground and were compiled in three Case Studies. Radiation doses measurements were also made, surface and underground locations, and compiled in other two Case Studies. There were sampled, at the same time, humidity, temperature, atmospheric pressure and relevant construction materials at sampling locations. They were collected and registration formed to analyse if there is any relation or contribution for the measured value in each specific place. Geostatistical models were used to elaborate maps of the results both for radiation values and for doses. Preliminary relations were established among the measured parameters.

Clinical-epidemiologic study of schistosomiasis mansoni in Ponte do Pasmado, a village in the municipality of Itinga, State of Minas Gerais, Brazil, 1992

A clinical-epidemiologic study of schistosomiasis mansoni was conducted in the population of Ponte do Pasmado, a village in the municipality of Itinga, state of Minas Gerais, Brazil. Faecal Parasitology by the Kato-Katz method and clinical examination were performed in 93.8% and 82.8% of the local population, respectively. A socioeconomic survey was also made and the signs and symptoms presented by the patients were recorded, as well as their contacts with natural waters. The rate of Schistosoma mansoni infection was 50.3%; the peak of infection occurred during the second decade of life; there was a predominance of low egg counts in faeces (85.89% of positive patients eliminated less than 500 eggs per gram of faeces); the splenomegaly rate was 1.23%. When the risk factors for S. mansoni infection were studied, significant risks were detected in activities such as fetching water, washing dishes, bathing, and crossing streams.

Bancroftian filariasis in two urban areas of Recife, Brasil: the role of individual risk factors

Bancroftian filariasis is spreading in towns of endemic areas as in Recife, northeastern Brazil, where it is a major public health problem. This paper deals with the prevalence of microfilaraemia and filarial disease in two urban areas of Recife, studying their association with individual characteristics and variables related to the exposure to the vectors. The parasitologic survey was performed through a "door-to-door" census and microfilaraemia was examined by the thick-drop technique using 45µl of peripheral blood collected between 20:00 and 24:00 o' clock. 2,863 individuals aged between 5 and 65 years were interviewed and submitted to clinical examination. Males aged between 15 and 44 years old presented the greatest risk of being microfilaraemic. Microfilaraemia was also significantly associated with no use of bednet to sleep. The risk of being microfilaraemic was greater among those who had lived in the studied areas for more than 5 years. The overall disease prevalence was 6.3%. Males presented the greatest risk of developing acute disease. The risk of developing chronic manifestations was also greater among males and increased with age. We found no association between time of residence, bednet use, microfilaraemia and acute and chronic disease. We may conclude that in endemic areas there are subgroups of individuals who has a higher risk of being microfilariae carriers due to different behaviours in relation to vector contact.

Schistosomiasis: predisposing cause for the formation of hepatic abscesses? Case report

An adult patient with chronic schistosomiasis from an endemic area, complained about a seven day fever, along with jaundice and lumbar backache on the right side. Image exams showed multiple pyogenic liver abscesses. All the classic etiologies were discarded through clinical, radiological and laboratorial criteria. Schistosomiasis can cause pylephlebitis as a complication, along with immunesuppression, granulomatous reaction with central lobular liver necrosis and a greater risk of infection. The authors suggest that schistosomiasis in its chronic form may be the predisposing cause of multiple pyogenic liver abscesses, especially in endemic areas.

Pulmonary manifestations in the initial phase of schistosomiasis mansoni

The clinical and radiological pulmonary manifestations in the initial phase of schistosomiasis mansoni were studied in thirty previously healthy individuals who were simultaneously infected. The findings were compared with those concerning a control group and related to possible pathogenetic factors. The respiratory manifestations were of light or of moderate intensity, the dry cough being the most common symptom. The significant radiological alterations were: thickening of bronchial walls and beaded micronodulation, predominantly localized in the lower pulmonary fields. It was observed significant association between wheezing and IgE levels, estimated by the area of immediate intradermal reaction, as well as between the number of blood eosinophils and the occurrence of radiological changes. Moreover, there was correlation between the worm burden and the presence of wheezing, thoracic pain and beaded micronodulation. Thus, the clinical and radiological pulmonary manifestations described are significant part of the initial phase of schistosomiasis mansoni and present the worm burden, eosinophilia and levels of IgE as probable pathogenetic factors.

Egg excretion in the initial phase of experimental murine schistosomiasis mansoni: stability and association with worm burden

Stability of faecal egg excretion and correlation with results related to worm burden at the initial phase of schistosomiasis mansoni were observed in two groups of mice infected with different Schistosoma mansoni cercarial burdens, by means of analysis of quantitative parasitological studies and schistosome counts after perfusion. Thus, it may be stated that few quantitative parasitological stool examinations could be sufficient to express the infection intensity at the initial phase, on the same grounds that it was already demonstrated at the chronic phase. Furthermore, it is confirmed that the use of the number of eggs passed in the faeces as a tool to estimate the worm burden at the initial phase of schistosome infection is adequate.

Spatial metrics and Landsat data for urban landuse change detection: case of Addis Ababa, Ethiopia.

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies.

TRH-TSH test in patients with schistosomiasis chronic forms

Diversas alterações na concentração sérica dos hormônios tiroidianos têm sido descritas em associação a doenças crônicas não-tiroidianas. Com relação às doenças hepáticas crônicas, a síndrome do T3 baixo foi descrita em pacientes cirróticos, enquanto a síndrome do T4 elevado foi encontrada em esquistossomóticos com a forma hepatoesplênica compensada. Com o intuito de verificar se as alterações relatadas na esquistossomose mansônica eram de origem "periférica" ou "central", realizamos a prova do TRH-TSH em 12 pacientes esquistossomóticos "puros" (6 hepatointestinais e 6 hepatoesplênicos compensados) e em 5 indivíduos controle. Os resultados obtidos demonstram que o eixo hipotálamo-hipofisário é normal nas formas crônicas da esquistossomose e que provavelmente as alterações previamente relatadas devem ser '"periféricas" e não " centrais".

IMMUNOSTIMULATION AS ADJUVANT FOR THE CHEMOTHERAPY OF EXPERIMENTAL SCHISTOSOMIASIS

Immunosuppressed animals respond poorly to schistosomal chemotherapy and that a proper response can be restored by the administration of immune serum. Present study attempts to search whether immunological stimulation would increase drug effectiveness. Swiss mice infected with 50 S. mansoni cercariae were later treated with complete Freund's adjuvant. Treatment with oxaminiquine was made with 100 mg/kg.b.w., 25 mg/kg.b.w. and 50 mg/kg/b.w., the last two doses representing a fourth and a half of the recommended curative dose. Appropriate controls for the drug, the adjuvant and the infection were also studied. The serum-level of ant-S. mansoni antibodies (ELISA) and recovery of worms by perfusion of the portal vein system were the evaluated parameters. Statistical analysis of the results failed to reveal significant differences in worm recovery between adjuvant-stimulated animals treated with oxamniquine and any of the treated controls receiving the same amount of the drug. Although total lack of immunity interferes with curative treament the usual immune response seems to be sufficient to allow for curative drug action in schistosomiasis and thus apparently does not need to be artificially stimulated

Polyvinyl alcohol-glutaraldehyde as solid-phase in Elisa for Schistosomiasis

Soluble adult Schistosoma mansoni antigen preparation (SWAP) was covalently fixed onto polyvinyl alcohol-glutaraldehyde discs and an enzyme linked-immunosorbent assay (ELISA) was set up. The best conditions for the assay were established and it was found that small amount of antigen such as 1.5 µg was required. A comparison between this procedure and the conventional ELISA was proceeded. A reliable method of antigen immobilization was achieved and the low prices of the employed reagents are economically attractive

A case of human rabies in the Urban Area of Ribeirão Preto, SP, Brazil

A 39-year old male patient was admitted to the University Hospital of the Faculty of Medicine of Ribeirão Preto with signs and symptoms of sudden dyspnea, generalized myalgia and behavioral disorders. The initial suspicion was alcohol abstinence syndrome and the patient was referred for psychiatric and neurologic care. The evolution of the patient with a worsening of signs and symptoms, presence of crises of tachypnea, agitation, difficulty to swallow, irritability and hydrophobia, and his report of having been bitten by a suspected dog raised the hypothesis of rabies. The diagnosis was confirmed by examination of a corneal impression, biological tests in the cerebrospinal fluid (CSF) and saliva and visualization of Negri bodies in nervous tissue (direct immunofluorescence). The patient evolved with agitation, aggressiveness, and worsening tachypnea intercalating with apnea, and died on the 4th day after admission

Decay of antibody isotypes against early developmental stages of Schistosoma mansoni after treatment of schistosomiasis patients

Antibodies to a number of parasite antigens are found in schistosomiasis patients, and antibodies to early developmental stages were demonstrated to be efficient immunologic markers for the diagnosis of schistosomiasis. In the present study, decay patterns of IgM and IgG antibodies against cercariae and schistosomula were investigated, in comparison to antibodies against worms and eggs in schistosomiasis patients after chemotherapy, for an investigation of seroepidemiologic aspects. Data obtained in the study of 359 serum samples from patients with Schistosoma mansoni infection, noninfected individuals, and patients followed-up for a period of 12 to 15 months after treatment provided the basis to postulate a general pattern for the kinetics of antibody decay. Before treatment, the antibody pattern was represented by a unimodal curve, which shifted to a bimodal curve after treatment, and ended with a unimodal curve similar to that for the noninfected group. Different types of antibodies were classified into four categories according to their decay features, and anti-schistosomulum IgM was classified into the moderate-decay caterogy, whereas other antibodies to early parasite stages were classified into the slow-decay category. The present methodology permits the identification of the most suitable antibodies to be detected in field control programs for schistosomiasis or other parasitoses

SCHISTOSOMIASIS MANSONI IN THE "BAIXADA OCIDENTAL MARANHENSE", STATE OF MARANHÃO, BRAZIL: CROSS-SECTIONAL STUDIES PERFORMED IN 1987 AND 1993

A cross-sectional study on the prevalence of schistosomiasis mansoni in three sites of the "Baixada Ocidental Maranhense" was carried out in 1993 in: Alegre (in the municipality of São Bento), Aliança (in Cururupu) and Coroatá II (in the municipality of São João Batista). Results were compared to those of another study performed at the same sites and in similar conditions, in 1987. The entire population of the three sites, with few exceptions, was submitted to fecal tests using the Kato-Katz method and immediate intradermal tests for schistosomiasis in both studies. Subjects with positive results in one of these tests were clinically evaluated by a physical examination. In 1993, the total of 827 subjects were submitted to fecal examination and 826 to intradermal test. Schistosoma mansoni eggs were found in the feces of 154 (18.6%) subjects, while 478 (57.9%) subjects presented a positive intradermal test. Stool examination was carried out in 367 subjects in Alegre with a positivity rate of 14.9%; the intradermal test, performed in 366 subjects, was positive in 47.5% of the cases. In Aliança, 277 subjects had their feces examined and were submitted to an intradermal test, with a positivity rate of 34.4% and 70.7%, respectively. Finally in Coroatá II, 183 inhabitants submitted to fecal and intradermal tests had positivity rates of 2.2% and 59.0%, respectively. When the present data were compared to those obtained in the survey performed in 1987, a significant decrease in the prevalence of infection by S. mansoni was observed in Alegre and Coroatá II, and a prevalence increase in Aliança.