Showing papers on "Schistosoma haematobium published in 1982"

Schistosomiasis of the female genital tract. A histopathological study of 176 cases from Malawi

Abstract: The histopathology of 176 cases of gynaecological schistosomiasis reported from Malawi during the period 1976-80 was reviewed. Schistosomal infection was found throughout the genital tract, with 60% of cases involving the cervix. The dominant tissue reactions to ova were categorized into five histopathological groups A-E and for each site the relationship between histopathological and clinical features was explored. No evidence was found linking schistosomiasis with cancer of the genital tract. Schistosomiasis was a significant cause of gynaecological morbidity, particularly when infection involved the lower genital tract; however in a proportion of cases ova were found coincidentally in other lesions or normal tissues, and were not apparently causally linked with symptoms. The findings are discussed in relation to previous studies of gynaecological schistosomiasis.

Mating behaviour in mixed infections of Schistosoma haematobium and S. intercalatum

Abstract: Summary Experiments were designed to examine the mating behaviour of Schistosoma haematobium and S. intercalatum in mixed infections in hamsters. Individual worms were identified by electrophoretic analysis of glucose-6-phosphate dehydrogenase which was characteristic for each isolate, in addition the uterine eggs of individual females were examined. The results showed that a specific mate recognition system does not exist for S. haematobium and S. intercalatum. The application of statistical tests to the results suggests that S. haematobium male worms are better at pairing with female worms of either species than S. intercalatum male worms. The significance of the results is discussed in relation to an occurrence of natural hybridization between these species in Cameroun.

Schistosoma haematobium in the baboon (Papio anubis): effect of vaccination with irradiated larvae on the subsequent infection with percutaneously applied cercariae.

Abstract: Groups of five baboons were vaccinated three times at approximately six-weekly intervals at a rate of 1,000 organisms per kg of γ-irradiated Schistosoma haematobium larvae. Five vaccines were tested: 3 and 20 Krad cercariae applied percutaneously; fresh 3 and 20 Krad mechanically transformed schistosomula injected intramuscularly; and cryopreserved 20 Krad schistosomula injected intramuscularly. These five groups and an unvaccinated control group were challenged percutaneously with 7,500 S. haematobium cercariae three months after the last vaccination. The efficacy of the vaccines was judged by faecal egg excretion, and by adult worm and tissue egg recoveries at necropsy 4.5 months after challenge. Significant protection, with 64 to 89% reductions in worm burden and parallel reductions in egg production, was achieved by all but the cryopreserved vaccine, although egg production was not significantly reduced in those female worms which did mature. Cercariae tended to give more protection than schistosomula and 20 Krad more protection than 3 Krad. No significant pathology could be detected in an additional baboon vaccinated with 20 Krad schistosomula but not challenged with cercariae. This is an encouraging result for the development of a live vaccine against S. haematobium .

Prevalence and intensity of Schistosoma haematobium infection in six villages of upper Egypt.

Abstract: A cross-sectional survey for Schistosoma haematobium infection in 5,998 individuals, representing 31,803 persons in six rural villages of the Qena governorate, Upper Egypt, was completed. There were 2,223 persons (37.1%) excreting S. haematobium eggs identified by the nuclepore membrane filtration technique of a single urine specimen. Prevalence of infection ranged from 23.9% to 64.0% among the six villages. Quantitatively the overall geometric mean egg-count was 48.1 eggs/10 ml urine. A survey of proximal canals was conducted and 9 of 4,312 Bulinus snails were infected with schistosomes (0.21%). The stools of 2 of 507 adolescent males were positive for S. mansoni. No Biomphalaria snails were found. When these findings are compared to past studies, S haematobium prevalence appears to have substantially increased.

Efficacy of metrifonate in urinary schistosomiasis: comparison of reduction of Schistosoma haematobium and S. mansoni eggs.

Abstract: Patients with schistosomiasis mansoni and schistosomiasis haematobium from the Gezira area of the Sudan were investigated for the simultaneous presence of Schistosoma mansoni and S. haematobium eggs in urine. Before treatment, 28 or 34 mixed-infection patients constantly excreted eggs of S. mansoni in the urine; however, the concentration was only 1.7% that of S. haematobium eggs. Patients were given two doses of metrifonate (10 mg/kg body weight) 2 weeks apart in order to compare the effect of the organophosphorous compound on the two parasite species. Each dose of metrifonate was followed by a significant decrease in egg output in urine (P less than 0.01). The egg reduction was similar for both parasite species, and was almost 99% after the second treatment. Before treatment was started, a positive correlation existed between the numbers of S. haematobium and S. mansoni eggs excreted in urine (r = 0.75, P less than 0.001), and this correlation did not change after the first or the second dose of metrifonate. After treatment, in 6 of 37 patients S. haematobium eggs and in 8 of 28 patients S. mansoni eggs were not, or were only slightly, reduced. When chemotherapeutic failure of metrifonate against S. haematobium or S. mansoni occurred, it was quantitatively similar for both parasite species.

Extraurinary schistosomiasis in Southern Iraq

Abstract: Ninety-six cases of extraurinary schistosomiasis due to Schistosoma haematobium were encountered in a retrospective histopathological study of cases encountered over a period of 12 years in Southern Iraq. Seventy-six cases involved three main systems, namely the female genital system (29 cases), male genital system (15 cases) and the lower intestinal tract (32 cases). In the remaining 20 cases unusual sites such as lymph nodes, skin, liver and lungs were affected. In none of these cases did the clinician initially consider schistosomiasis to be the cause of the patient's illness prior to the histological diagnosis.

Progress in the national schistosomiasis control programme of Iran.

Abstract: A combination of chemotherapy and mollusciciding has been used in Khuzestan, south-west Iran, since 1966, to try to control urinary schistosomiasis. The total amount of molluscicide used each year varied between 702 and 3505 kg and between 287 and 1320 infected persons were detected and treated annually. The prevalence of infection has gradually declined from 8.3% in 1970 to 0.7% in 1979. Similarly, the incidence of infection among schoolchildren decreased from 3.5% in 1970 to 0.7% in 1979. The proportion of Bulinus-infested habitats also decreased from 10% in 1971 to 2.4% in 1979.

A study on the etiological factors of bilharzial bladder cancer in Egypt. 6. The possible role of urinary bacteria.

Abstract: A correlation was obtained between a positive nitrite test in urine and the severity of urinary bacterial infection. Bacteria isolated from the urine of bilharzial or bladder cancer patients were found to be rich in nitrate reductase activity. "Escherichia coli" was the most common microorganism isolated from these specimens. Urine and several urinary constituents activate bacterial nitrate reductase. beta-Glucuronidase activity in the urine of patients with chronic "Schistosoma haematobium" infection and bladder cancer was measured and shown to be significantly greater than that of urine of normal control subjects. Urinary bacterial infection was shown to be the source of the increased urinary level of enzyme activity at pH 7.0.

Cytologic detection of bladder cancer in a rural Egyptian population infected with schistosomiasis.

Abstract: A study was initiated in September 1976 to detect early bladder carcinoma by selective cytologic screening in a rural Egyptian population infested with Schistosoma haematobium. All persons in a high-risk group, i.e., farmers aged 20 years and above, and selected persons from two low-risk groups were screened. Bladder carcinoma was detected in 11 patients among the 4,769 individuals screened in the high-risk group, for a yield of 2.3 per 1,000. No tumors were detected in the 3,975 individuals in the low-risk groups. Cytologically diagnosed tumors were verified by histology in all cases. One of the detected tumors in a female was found to be metastatic from carcinoma of the cervix. The primary tumors included five squamous cell carcinomas, four transitional cell carcinomas and one undifferentiated carcinoma. Seven of the tumors were at early stages, including three noninvasive (TIS) and four superficial (T1 and T2) ones. This investigation indicates that selective cytologic screening in the high-risk group in Egypt is feasible and effective for the early detection of bladder carcinoma associated with schistosomiasis.

[Value of macroscopic urine examination and reagent strips for the detection of hematuria and proteinuria in the mass diagnosis of urinary schistosomiasis, before and after treatment]

Abstract: In this study, dip-stick examination for the detection of hematuria and proteinuria, and macroscopic examination of the urine as diagnostic methods for mass screening for urinary schistosomiasis, were compared with the technique of urinary filtration for Schistosoma haematobium eggs. Dip-sticks and macroscopic examination were proved to be simple and rapid. Before treatment, the revealing of hematuria by dip-stick was shown to be a sensitive method by comparison with filtration, but it is not specific. The tests for proteinuria, and macroscopic examination are more specific, but less sensitive. Nevertheless, all these methods give similar prevalences as distributed by age groups. Dip-sticks and macroscopic exams could therefore be duly considered for the detection of new high endemic regions. After treatment, these methods result in less valid prevalences than those obtained by filtration, but their specificity increases; they become good indicators of clinical improvement.

Analysis and preliminary purification of glycoproteins isolated from eggs in the urine of patients with Schistosoma haematobium infection.

Abstract: Preliminary analysis and purification of glycoproteins from Schistosoma haematobium eggs were carried out with a small quantity of antigenic material obtained from the urine of infected human patients. A soluble egg extract was 125I-labeled and was fractionated by lectin affinity chromatography for separating egg glycoproteins. The crude glycoprotein fraction was run on SDS-PAGE to yield three polydisperse peaks with Rf values of 0.31, 0.57, and 0.84. 125I-labeled egg glycoproteins were further fractionated by ion exchange chromatography to yield four peaks or shoulders. One of these peaks constituted the major labeled egg glycoprotein of S. haematobium (MEGL-H) in a relatively pure form as determined by SDS-PAGE, and its estimated m.w. was 70,000. This glycoprotein was consistently and highly reactive serologically with a serum pool from schistosomiasis haematobia patients by a Farr-type radioimmunoassay (RIA). A limited cross-specificity study of inhibition RIA indicated that S. mansoni eggs contain components that cross-react only partially with MEGL-H. These results focus attention on MEGL-H as a potential serodiagnostic probe.

Bulinus coulboisi of Lake Tanganyika: assessment of its taxonomic position and role as intermediate host for S. haematobium

Abstract: Summary The freshwater snail Bulinus coulboisi (Bourguignat) has been reported by previous authors to occur in a large area of central and eastern Africa, and to be a potential intermediate host for Schistosoma haematobium. In order to establish the taxonomic position of B. coulboisi, the present authors made observations on preserved specimens from the type-locality on the western shore of Lake Tanganyika, and on snails collected alive at Kigoma on the eastern shore. Information is presented for the shell, radula, copulatory organ, egg proteins, certain enzymes and chromosome number. The tetraploid chromosome number (2n=72), biochemical features and morphological characteristics of our materials provide evidence that B. coulboisi is a southern form of B. truncatus (Audouin, 1827). The latter species is widespread in northern Africa and is an important intermediate host for S. haematobium, particularly in Egypt and Sudan. The present observations and those of other authors indicate that B. coulboisi lives...

Comparison of the cercarial chaetotaxy of 10 species of schistosomes

Abstract: The cercarial chaetotaxy permits the differenciation of four groups of Schistosomatinae. --Schistosomatium douthitti, parasite of Stagnicola and Lymnaea (Lymnaeidae); --Schistosoma japonicum, parasite of Oncomelania (Melaniidae); --Schistosoma mansoni and S. rodhaini, parasites of Biomphalaria (Planorbiinae, Bulinidae); --Schistosoma haematobium, S. bovis, S. margrebowiei, S. mattheei, S. leiperi and S. intercalatum, parasites of Isidora, Physopsis and Bulinus (Bulininae, Bulinidae). For the third group, cercaria of Schistosoma mansoni and S. rodhaini may be distinguished. In the fourth group, small statistical differences in the topography of the sensillae can be shown between the various species.

Treatment of urinary and intestinal bilharziosis with praziquantel. Apropos of 182 cases

Abstract: 182 patients representing 188 cases of schistosomiasis (including 152 S. haematobium, 34 S. mansoni, and 2 S. intercalatum cases) were treated with praziquantel using 40 mg/kg in a single intake. Biological check-up did not reveal any abnormality that could have been related to the treatment. Clinical side-effects appeared in 25% cases and were essentially gastrointestinal symptoms, headaches, dizziness. Efficiency was assessed by direct parasitological examinations of the feces or urine that were performed after treatment. It reached 91% for S. haematobium and 95% for S. mansoni schistosomiasis.