Macrophages are required for host survival in experimental urogenital schistosomiasis.

Urogenital schistosomiasis, Schistosoma haematobium worm infection, afflicts millions of people with egg-triggered, fibrotic bladder granulomata. Despite the significant global impact of urogenital schistosomiasis, the mechanisms of bladder granulomogenesis and fibrosis are ill defined due to the prior lack of tractable animal models. We combined a mouse model of urogenital schistosomiasis with macrophage-depleting liposomal clodronate (LC) to define how macrophages mediate bladder granulomogenesis and fibrosis. Mice were injected with eggs purified from infected hamsters or vehicle prepared from uninfected hamster tissues (xenoantigen and injection trauma control). Empty liposomes were controls for LC: 1) LC treatment resulted in fewer bladder egg granuloma-infiltrating macrophages, eosinophils, and T and B cells, lower bladder and serum levels of eotaxin, and higher bladder concentrations of IL-1α and chemokines (in a time-dependent fashion), confirming that macrophages orchestrate leukocyte infiltration of the egg-exposed bladder; 2) macrophage-depleted mice exhibited greater weight loss and bladder hemorrhage postegg injection; 3) early LC treatment postegg injection resulted in profound decreases in bladder fibrosis, suggesting differing roles for macrophages in fibrosis over time; and 4) LC treatment also led to egg dose-dependent mortality, indicating that macrophages prevent death from urogenital schistosomiasis. Thus, macrophages are a potential therapeutic target for preventing or treating the bladder sequelae of urogenital schistosomiasis.

Host tissue proteomics reveal insights into the molecular basis of Schistosoma haematobium-induced bladder pathology.

Urogenital schistosomiasis remains a major public health concern worldwide. In response to egg deposition, the host bladder undergoes gross and molecular morphological changes relevant for disease manifestation. However, limited mechanistic studies to date imply that the molecular mechanisms underlying pathology are not well-defined. We leveraged a mouse model of urogenital schistosomiasis to perform for the first time, proteome profiling of the early molecular events that occur in the bladder after exposure to S. haematobium eggs, and to elucidate the protein pathways involved in urogenital schistosomiasis-induced pathology. Purified S. haematobium eggs or control vehicle were microinjected into the bladder walls of mice. Mice were sacrificed seven days post-injection and bladder proteins isolated and processed for proteome profiling using mass spectrometry. We demonstrate that biological processes including carcinogenesis, immune and inflammatory responses, increased protein translation or turnover, oxidative stress responses, reduced cell adhesion and epithelial barrier integrity, and increased glucose metabolism were significantly enriched in S. haematobium infection. S. haematobium egg deposition in the bladder results in significant changes in proteins and pathways that play a role in pathology. Our findings highlight the potential bladder protein indicators for host-parasite interplay and provide new insights into the complex dynamics of pathology and characteristic bladder tissue changes in urogenital schistosomiasis. The findings will be relevant for development of improved interventions for disease control.

Schistosomiasis: a case study.

Schistosomiasis is a parasitic infection caused by trematodes (flatworms). It is second only to malaria in public health significance, with an estimated 200 million people infected worldwide. Schistosoma haematobium is endemic in Africa and the Middle East. This case study discusses a 36-year-old Somalian male who immigrated to a Northeastern city in the United States from a refugee camp in Kenya. He presented with episodic gross hematuria and flank pain, and was eventually diagnosed with urinary tract schistosomiasis, which was successfully treated with praziquantel. While the disease is not common in the United States, this case is presented for both its urological and cultural considerations.

Cytokine responses to Schistosoma haematobium in a Zimbabwean population: contrasting profiles for IFN-gamma, IL-4, IL-5 and IL-10 with age.

BACKGROUND: The rate of development of parasite-specific immune responses can be studied by following their age profiles in exposed and infected hosts. This study determined the cytokine-age profiles of Zimbabweans resident in a Schistosoma haematobium endemic area and further investigated the relationship between the cytokine responses and infection intensity. METHODS: Schistosome adult worm antigen-specific IFN-gamma, IL-4, IL-5 and IL-10 cytokine responses elicited from whole blood cultures were studied in 190 Zimbabweans exposed to S. haematobium infection (aged 6 to 40 years old). The cytokines were measured using capture ELISAs and the data thus obtained together with S. haematobium egg count data from urine assays were analysed using a combination of parametric and nonparametric statistical approaches. RESULTS: Age profiles of schistosome infection in the study population showed that infection rose to peak in childhood (11-12 years) followed by a sharp decline in infection intensity while prevalence fell more gradually. Mean infection intensity was 37 eggs/10 ml urine (SE 6.19 eggs/10 ml urine) while infection prevalence was 54.7%. Measurements of parasite-specific cytokine responses showed that IL-4, IL-5 and IL-10 but not IFN-gamma followed distinct age-profiles. Parasite-specific IL-10 production developed early, peaking in the youngest age group and declining thereafter; while IL-4 and IL-5 responses were slower to develop with a later peak. High IL-10 producers were likely to be egg positive with IL-10 production increasing with increasing infection intensity. Furthermore people producing high levels of IL-10 produced little or no IL-5, suggesting that IL-10 may be involved in the regulation of IL-5 levels. IL-4 and IFN-gamma did not show a significant relationship with infection status or intensity and were positively associated with each other. CONCLUSION: Taken together, these results show that the IL-10 responses develop early compared to the IL-5 response and may be down-modulating immunopathological responses that occur during the early phase of infection. The results further support current suggestions that the Th1/Th2 dichotomy does not sufficiently explain susceptibility or resistance to schistosome infection.

Effect of temperature on the Bulinus globosus - Schistosoma haematobium system.

BACKGROUND: Given that increase in temperature may alter host-parasite relationships, the anticipated rise in temperature due to global warming might change transmission patterns of certain diseases. However, the extent to which this will happen is not well understood. METHODS: Using a host-parasite system involving Bulinus globosus and Schistosoma haematobium, we assessed the effect of temperature on snail fecundity, growth, survival and parasite development under laboratory conditions. RESULTS: Our results show that temperature may have a non-linear effect on snail fecundity and snail growth. Snails maintained at 15.5 °C and 36.0 °C did not produce egg masses while those maintained at 25.8 °C laid 344 and 105 more egg masses than snails at 31.0 °C and 21.2 °C, respectively. Attainment of patency led to a reduction in egg mass production among the snails. However, the reduction in fecundity for snails maintained at 21.2 °C occurred before snails started shedding cercariae. Parasite development was accelerated at high temperatures with snails maintained at 31.0 °C reaching patency after three weeks. Furthermore, snail growth rate was highest at 25.8 °C while it was inhibited at 15.5 °C and reduced at 31.0 °C. Increase in temperature increased snail mortality rates. Snails maintained at 36.0 °C had the shortest survival time while those maintained at 15.5 °C had the longest survival time. CONCLUSIONS: We concluded that temperature influences fecunxdity, growth, survival and parasite development in the snail and thus dictates the time it takes the parasite to complete the life cycle. This has implications on transmission of schistosomiasis in the context of global warming.

Development and testing of Schisto and Ladders™, an innovative health educational game for control of schistosomiasis in schoolchildren.

BACKGROUND: Schistosomiasis remains a public health problem in many regions of the world, including Nigeria. Current control strategy involves mass drug administration with praziquantel to the endemic population. To complement and sustain on-going preventive chemotherapy, we developed a health educational game named Schisto and Ladders™ and tested its potential for the control of schistosomiasis among schoolchildren living in Imala-Odo, a highly endemic community near Abeokuta, Nigeria. METHODS: One hundred school children were randomly selected and divided into intervention and control groups through balloting. Their knowledge, attitudes and practices (KAP) concerning schistosomiasis transmission, control and prevention were assessed using structured questionnaires. Schisto and Ladders™ game were given to the intervention group and the popular Snake and Ladders™ game to the control group. Both games were played for 2 months under the supervision of their class teachers. A post-KAP assessment was carried out in both groups, including focus group discussions (FGDs) to investigate knowledge and the impact of the games. RESULTS: Knowledge about urinary schistosomiasis and its transmission significantly improved (P = 0.000) in the intervention group (68.0%) compared to the control group (8.0%). FGDs showed that the frequency of visits to dam water also significantly reduced (P = 0.048) in the intervention group (18.0%) compared to the control group (40.0%). There was a significant increase in knowledge regarding risk behaviours, prevention and control of schistosomiasis among the intervention group, but no new knowledge gained in the control group. CONCLUSIONS: This study demonstrates the potential of the health education game Schisto and Ladders™ for teaching basic health education and promoting behavioural changes among schoolchildren in endemic communities.

Maternal urogenital schistosomiasis; monitoring disease morbidity by simple reagent strips.

BACKGROUND: Urine analysis is one of the recommended antenatal guidelines for early diagnosis of pregnancy-associated complications. While in practice, urine analysis by dipstick had been used to provide useful information on other urinary tract infections, its applications for early detection of urogenital schistosomiasis in pregnant women is often times not given due attention in most endemic areas. Our study therefore assessed the performance of some common urinalysis parameters in the diagnosis of maternal urogenital schistosomiasis in endemic rural communities of Nigeria. METHODOLOGY/PRINCIPAL FINDINGS: The cross-sectional epidemiologic survey of urogenital schistosomiasis was conducted among pregnant women in Yewa North Local Government, Ogun State, Nigeria. The women were microscopically examined for infection with Schistosoma haematobium, visually observed for macrohematuria, and screened for microhematuria and proteinuria using standard urine chemical reagent strips. Of 261 volunteered participants, 19.9% tested positive for S. haematobium infection. The proportion of microhematuria (23.8%) was significantly higher than that of macrohematuria (3.8%) and proteinuria (16.8%) (P<0.05). Microhematuria with sensitivity (82.7%) and specificity (89.0%) was the best diagnostic indicator of urogenital schistosomiasis. Macrohematuria with the least sensitivity (11.8%) was however the most specific (98.1%) for diagnosing urogenital schistosomiasis in pregnant women. Maximum microhematuria sensitivity (100.0%) was observed in women between 15-19 years but sensitivity was consistently low in older age groups. Maximum sensitivity, specificity and predictive values (100.0%) were recorded for microhematuria in first trimester women. Diagnostic efficiency of proteinuria and macrohematuria was also better in the first trimester women except the 25.0% specificity recorded for proteinuria. The overall diagnostic performance of microhematuria and proteinuria was better in secundigravidae. CONCLUSIONS/SIGNIFICANCE: Microhematuria can be used for early detection of urogenital schistosomiasis in endemic areas especially in younger women. However because microhematuria is a condition that occurs during pregnancy and in several other diseases, it is necessary to compliment the diagnosis with other diagnostic tools such as microscopy and serology. Treatment with praziquantel is recommended for the women in their late trimesters after follow up test in order to avert associated adverse pregnancy outcomes.

Urogenital schistosomiasis during pregnancy is associated with low birth weight delivery: analysis of a prospective cohort of pregnant women and their offspring in Gabon.

An estimated 40 million women of childbearing age suffer from schistosomiasis. Animal models indicate a deleterious effect of maternal schistosomiasis on pregnancy outcomes. To date there is a lack of epidemiological evidence evaluating schistosomiasis-related morbidity in pregnancy. This study was designed to describe the impact of urogenital schistosomiasis on pregnancy outcomes in a highly endemic region of central Africa. Pregnant women attending antenatal clinics in Fougamou and Lambaréné, Gabon, were consecutively screened for the presence of Schistosoma haematobium eggs in diurnal urine samples. Maternal and newborn characteristics assessed at delivery were compared between infected and uninfected mothers. The impact of maternal schistosomiasis on low birth weight and preterm delivery was assessed using logistic regression analysis. Urogenital schistosomiasis was diagnosed in 103 (9%) of 1115 pregnant women. Maternal age was inversely associated with the prevalence of urogenital schistosomiasis, with a higher burden amongst nulliparous women. Low birth weight was more common amongst infants of S. haematobium-infected mothers. This association was unaffected by controlling for demographic characteristics, gestational age and Plasmodium infection status (adjusted Odds Ratio 1.93; 95% confidence interval: 1.08-3.42). Other risk factors associated with low birth weight delivery were underweight mothers (adjusted Odds Ratio 2.34; 95% confidence interval: 1.12-4.92), peripheral or placental Plasmodium falciparum infection (adjusted Odds Ratio 2.04; 95% confidence interval: 1.18-3.53) and preterm birth (adjusted Odds Ratio 3.12; 95% confidence interval: 1.97-4.96). Preterm delivery was not associated with S. haematobium infection (adjusted Odds Ratio 1.07 95% confidence interval: 0.57-1.98). In conclusion, this study indicates that pregnant women with urogenital schistosomiasis are at an increased risk for low birth weight deliveries. Further studies evaluating targeted treatment and prevention programmes for urogenital schistosomiasis in pregnant women and their impact on delivery outcomes are warranted.

Anemia and growth retardation associated with Schistosoma haematobium infection in Mali: a possible subtle impact of a neglected tropical disease.

Background: The aim of this cross-sectional study was to investigate a possible association of Schistosoma haematobium with child growth development and describe a plausible schistosomiasis-related anemia in children and adults in a highly schistosomiasis endemic area of Mali. Methods: Urine, feces and blood samples from 399 participants of both sexes (2-40 years of age) were analyzed and supplemented by anthropometric measurements. Results: S. haematobium prevalence was 79.8%, S. mansoni 13.2% and Plasmodium falciparum 80.2%. S. haematobium infection intensity as five categories was significantly associated with anemia; i.e., odds of having anemia in the highest and the next highest category was 3.25 (95% CL 1.61-6.55; p<0.01) and 2.45 (95% CL 1.28-4.70; p<0.01), respectively, of that in the three lower categories combined after adjusting for age group and gender and the interaction between the two factors. Anemia was most pronounced in the 2-5 year olds males (55.5%, n=98). P. falciparum infection was not significantly associated with anemia. Stunting (body mass index [BMI] for age z-score<-2.00) was observed in 2.6% (2/78) of the 2-5 years olds and in 7.7% (14/182) in the 6-19 years age group. Lower BMI-z-scores (as continuous variable) were associated with anemia (p<0.05) while high intensity of S. haematobium infection was not significant when adjusting for age group and anemia. Participants with malaria infection had lower z-scores (as continuous variables) of weight and height for age. Lower height for age z-scores were also associated with anemia. Conclusions: S. haematobium infection is likely to impact on child growth and possibly also anemia in all age groups and advocates for inclusion of whole populations into future control programes.

Inflammation, chromosomal instability, and cancer: the schistosomiasis model.

Evidence is accumulating in support of a role for reactive oxygen species in the etiology of cancer. Inflammatory cells, such as neutrophils, macrophages, and eosinophils, are an important endogenous source of oxygen radicals. Stimulation of these cells by tumor promoters or by foreign bodies (parasites, bacteria, etc.) causes the release of reactive oxygen species. Laboratory studies have shown that genetic damage and neoplastic transformation are induced in vitro in cells cocultured with activated inflammatory cells. We have recently begun to study the role of inflammatory reactions in inducing genetic damage in a human population. This paper describes our initial studies of Egyptian patients infected with Schistosoma haematobium. This infection induces chronic inflammation and irritation in the urinary bladder and is associated with increased cancer at this site. We describe a recently completed population study that shows that infected individuals have elevated levels of genetic damage in their bladders, as measured by the exfoliated cell micronucleus test. Treatment that kills the parasite also reduces the micronucleus frequencies. We also explore the hypothesis that altered sensitivity of clones of cells in these patients to reactive oxygen species could be a force that drives the development of neoplasia by facilitating clonal expansion. Evidence is presented for the possible involvement of loci on chromosome 11 in controlling the level of chromosomal breakage caused by oxidative damage. We have shown that bladder carcinoma cells are sensitive to micronucleus induction by promoter-activated neutrophils and that they can be protected from this damage by insertion of a normal chromosome 11. Further work is in progress to define the source of chromosomal breakage in schistosomiasis patients and to begin to develop an understanding of the host factors protecting bladder cells in these individuals from genetic damage.

Late benefits 10-18 years after drug therapy for infection with Schistosoma haematobium in Kwale District, Coast Province, Kenya.

Late benefits of remote antischistosomal therapy were estimated among long-term residents of an area with high transmission of Schistosoma haematobium (Msambweni, Kenya) by comparing infection and disease prevalence in two local adult cohorts. We compared 132 formerly treated adults (given treatment in childhood or adolescence > or = 10 years previously) compared with 132 age- and sex-matched adults from the same villages who had not received prior treatment. The prevalence of current infection, hematuria, and ultrasound bladder abnormalities were significantly lower among the previously treated group, who were found to be free of severe bladder disease. Nevertheless, heavy infection was equally prevalent (2-3%) in both study groups, and present rates of hydronephrosis were not significantly different. Therapy given in childhood or adolescence appears to improve risk for some but not all manifestations of S. haematobium infection in later adult life. Future prospective studies of continued treatment into adulthood will better define means to obtain optimal, community-based control of S. haematobium-related disease in high-risk locations.

In Ivorian school-age children, infection with hookworm does not reduce dietary iron absorption or systemic iron utilization, whereas afebrile Plasmodium falciparum infection reduces iron absorption by half.

BACKGROUND: In sub-Saharan Africa, parasitic diseases and low bioavailable iron intake are major causes of anemia. Anemia results from inflammation, preventing iron recycling and decreasing dietary iron absorption. Hookworm, Plasmodium, and Schistosoma infections contribute to anemia, but their influence on dietary iron absorption and recycling is unknown. OBJECTIVE: The objective was to measure inflammation biomarkers, hepcidin, iron absorption, and utilization pre- and posttreatment in children with afebrile malaria, hookworm, and Schistosoma haematobium infection. DESIGN: Ivorian children aged 11-17 y with afebrile Plasmodium falciparum (n = 17), hookworm (n = 16), or S. haematobium infection (n = 8) consumed a syrup containing 3 mg 57Fe as ferrous sulfate and received an intravenous infusion of 50 µg 58Fe as ferrous citrate. Children were treated for their respective infection, and the iron studies were repeated 4 wk later. Iron and inflammation biomarkers and hepcidin were measured. RESULTS: Geometric mean iron absorptions in the afebrile malaria and hookworm groups were 12.9% and 32.2% (P < 0.001) before treatment and 23.6% and 30.0% (P = 0.113) after treatment, respectively. Treatment of afebrile malaria reduced inflammation (P < 0.001) and serum hepcidin (P = 0.004) and improved iron absorption (P = 0.003). Treatment of hookworm infection neither affected inflammation biomarkers nor altered iron absorption. Similarly, there was a lack of treatment effects in the S. haematobium-infected group; however, the small sample size limits conclusions. Geometric mean iron utilization ranged between 79.1% and 88.0% in the afebrile malaria and hookworm groups with no significant differences pre- and posttreatment. CONCLUSIONS: In school-age children, hookworm infection does not produce inflammation or increase serum hepcidin, and it does not influence iron absorption or utilization. In contrast, afebrile malaria causes inflammation, increases hepcidin, and reduces iron absorption but not utilization. These findings provide insights into the iron metabolism and the etiology of anemia in parasitic infections.

The pathobiology of Schistosoma haematobium infection in humans.

Schistosoma haematobium infection is a common occurrence in Africa and the Middle East and is the world's leading cause of hematuria. Since more North Americans are venturing into endemic areas and more residents of endemic areas are seeking medical care in North America, pathologists must be able not only to diagnose urinary schistosomiasis but also to provide advice as to further therapy. These endeavors mandate knowledge of the pathobiologic features of the disease. The severity and frequency of the sequelae of urinary schistosomiasis (hydroureter, hydronephrosis, bladder ulcer, and polyposis) and of its complications (bacterial urinary tract infection, renal failure, urothelial cancers) depend on the intensity of infection, i.e., worm burden and tissue egg burden, and the duration of infection. Significant differences in gross and microscopic morphology, clinical laboratory findings, and optimal mode of treatment exist between active (during active egg deposition) and inactive (after cessation of oviposition) disease. Moreover, nearly half of the severe sequelae and complications occur during the inactive phase of the disease, when diagnosis is most difficult. The manifestations of this disease are manifold and complex, and firm understanding of the pathobiologic features is necessary if pathologists are to understand their role in the direction of treatment.

Relationships of Schistosoma haematobium, hookworm and malarial infections and metrifonate treatment to growth of Kenyan school children.

Relationships of S. haematobium, hookworm and malarial infections to growth 6 months after metrifonate treatment were studied in Kenyan primary school children in an area where poor growth, S. haematobium and hookworm were common and malaria was endemic. All children with light-moderate S. haematobium infections (1-500 eggs/10 ml adj) in 4 schools were examined (Exam 1), allocated at random to either placebo (MIP, n = 198) or metrifonate treatment (MIT, n = 201) groups, treated, and examined again 6 months later (Exam 2). An additional 19 heavily infected children (HIT group greater than 500 eggs/10 ml adj) were treated immediately after Exam 1 and also followed. The MIT and HIT groups exhibited more rapid growth between Exam 1 and 2 than did the placebo group. The MIT group gained significantly (P less than 0.001) more than the MIP group in weight (0.8 kg), percent weight for age (2.3 percentage points), weight for height squared (0.04 units), arm circumference (0.4 cm), percent arm circumference for age (1.7 percentage points) and in triceps and subscapular skinfold thicknesses. In addition, the placebo group showed statistically significant decreases between exams in percentage weight for age, percent arm circumference for age, both skinfold thicknesses for age and no significant increase in percent height for age while the MIT group exhibited highly significant increases in all anthropometric parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantification of clinical morbidity associated with schistosome infection in sub-Saharan Africa.

Health policy making in developing countries requires estimates of the (global) burden of disease. At present, most of the available data on schistosomiasis is limited to numbers of individuals harbouring the infection. We explored the relationship between the presence of schistosome infection and clinical morbidity, in order to estimate numbers of individuals with disease-specific morbidity for Schistosoma haematobium and Schistosoma mansoni infection in sub-Saharan Africa. We searched the literature for cross-sectional data from field studies reporting both schistosome infection and morbidity. This was used to derive a functional relationship between morbidity and infection. After standardisation for diagnostic method, the number of individuals with specific types of clinical morbidity or pathology was predicted. As only aggregated prevalences of infection were available for countries or areas, we adjusted for heterogeneity in infection levels within communities in those countries. In total, 70 million individuals out of 682 million (2000 estimate) in sub-Saharan Africa were estimated to experience haematuria in the last 2 weeks associated with S. haematobium infection, and 32 million dysuria. Ultrasound detected serious consequences of S. haematobium, major bladder wall pathology and major hydronephrosis, were predicted at 18 and 10 million, respectively. Infection with S. mansoni was estimated to cause diarrhoea in 0.78 million individuals, blood in stool in 4.4 million and hepatomegaly in 8.5 million. As the associations between prevalence of S. mansoni infection and prevalence of diarrhoea and blood in stool were not very clear, the resulting estimates may be underestimations. Using the very limited data available, we estimated the mortality rates due to non-functioning kidney (from S. haematobium) and haematemesis (from S. mansoni) at 150000 and 130000 per year. Given the overall high number of cases with schistosomiasis-related disease and associated death, we conclude that schistosomiasis remains an important public health problem in sub-Saharan Africa.

Involvement of inflammatory reactions and elevated cell proliferation in the development of bladder cancer in schistosomiasis patients.

Schistosoma haematobium infection is strongly associated with urinary bladder cancer. Although numerous explanations have been proposed for this association, the nature of this relationship remains unresolved. This paper explores the hypothesis that inflammation and elevated cell proliferation play a major role in the development of bladder cancer in infected patients, possibly by increasing the level of genetic instability in the urothelium. The paper details in vivo and in vitro studies being done in our laboratories to test this hypothesis. These studies include population studies in which chromosomal breakage in the bladder of infected individuals is assayed using the micronucleus (MN) test on exfoliated urothelial cells. The approach also includes parallel studies in Vancouver with patients with long-term catheter drainage, a population with many similarities to schistosomiasis patients. In the in vitro studies we are co-incubating bladder cells with activated neutrophils or experimental conditions simulating inflammation. These studies show that inflammatory cells when activated can induce micronuclei in bladder cells and that this response is associated with loci on chromosome 11, a chromosome commonly altered during bladder carcinogenesis. A final approach being used is to assay chromosomal change (MN frequencies and numerical chromosome alterations) and level of proliferation (expression of proliferating cell nuclear antigen) in archival biopsies from schistosomiasis patients. Preliminary results show that a dysregulation of cell proliferation is occurring during cystitis in these patients. The extent to which this alteration affects the level of chromosomal breakage is yet to be determined.

Female genital schistosomiasis as a risk-factor for the transmission of HIV.

Sexually transmitted diseases increase the probability for HIV transmission, presumably through lesions in the genital mucosa. Female genital schistosomiasis, a special form of urinary schistosomiasis due to infection with Schistosoma haematobium, may be another risk-factor for transmission of HIV. From published data there seem to be pathophysiological, immunological and epidemiological evidence for an association between genital ulcer disease due to S. haematobium and HIV-infection in women. Female genital schistosomiasis could be seen as an example of how an interaction between a parasitic disease and HIV facilitates the propagation of the latter. As long as the prevalence of HIV is low in the general population, interventions targeted to high risk groups will significantly delay, or even prevent, widespread dissemination of the HIV infection in the rest of the population. If female genital schistosomiasis is a risk factor for the spread of HIV like other genital ulcer diseases, there should be interesting ways to intervene from the public health point of view.

PIP: Recent epidemiologic, immunologic, and pathophysiologic data suggest that female genital schistosomiasis, a special form of urinary schistosomiasis due to infection with the trematode Schistosoma haematobium, may be a risk factor for human immunodeficiency virus (HIV) in the 44 African countries where these infections coexist. Eggs of the parasite are found in the organs of the female genital tract (vagina, vulva, and cervix), as well as in urine. Epidemiologists have estimated that 90 million Africans are infected with S. haematobium and that 35-100% of so infected women of childbearing age suffer intermittently from genital lesions caused by eggs sequestered within the epithelium. Lesions associated with this disease tend to be multiple and bleed easily, spontaneously or on contact. Women heavily infected with S. haematobium or S. mansoni show a decrease in the number of circulating CD4+ T cells and NK cells; moreover, a cross-reactivity between HIV-1 virion infectivity factor and a surface antigen to S mansoni has been shown. The eroded, friable epithelium of women with genital schistosomiasis provides HIV with access to deeper cell layers; moreover, the abundance of CD4+ cells and macrophages within the confines of the granuloma makes rapid binding of HIV more likely than is the case with other sexually transmitted diseases. The greatest increase in HIV prevalence in the past decade has occurred in Uganda, Kenya, Malawi, and the Central African Republic--countries with S. haematobium rates of about 70%. In addition, the HIV prevalence rate in areas highly endemic for this parasite is 1.2-1.7 times greater in women than men. Needed, to confirm this association, are correlation studies of increases in HIV prevalence over time in women 15-30 years of age and rates of genital schistosomiasis.

Traditional herbal remedies used for the treatment of urinary schistosomiasis in Zimbabwe.

A total of 286 traditional healers, 85% of them registered with the Zimbabwe National Traditional Healers' Association (ZINATHA), in five administrative provinces of Zimbabwe, were interviewed to assess their knowledge about the signs and symptoms of urinary schistosomiasis. Information on the names of plants used to treat Schistosoma haematobium infections was solicited. Haematuria was mentioned by 99% of the traditional healers to be the most obvious sign of S. haematobium infection. General body weakness, increased urinary frequency and pain on micturition also were reported to be some of the signs of infection. Eight plant materials were identified as the most commonly used for the treatment of S. haematobium. The plants were identified and parts collected to investigate their antischistosomal properties. The plant materials were prepared according to the guidelines of the traditional healers and their efficacy determined by administering the crude extracts orally to hamsters infected with S. haematobium cercariae. The results obtained suggested that plant extracts from Abrus precatorius (Leguminosae), Pterocarpus angolensis (Leguminosae) and Ozoroa insignis (Anacardiaceae) were lethal to adult schistosomes.

Urinary symptoms and blood pressure of children with Schistosoma haematobium infection in south-eastern Nigeria.

The urinary symptoms and blood pressures of 510 children (aged 5-15 years) with Schistosoma haematobium infection in Ijiman community, Cross River State of Nigeria, were studied in 1992. The prevalence rate of infection was 44%, a majority of the children presenting with light infection. Significant symptoms were visible haematuria, dysuria, suprapubic pain and strangury. The sensitivity and specificity of these symptoms were too low for them to be recommended as distinct clinical diagnostic criteria. The impact of the disease could not be demonstrated on blood pressures of the children. Nevertheless, urgent control measures with emphasis on the provision of ventilated improved pit toilets and potable water are strongly recommended for the control of the disease as persistent infection is known to mask manifestation of severe complications till an older age.

[Bladder schistosomiasis. Etiologic diagnosis of detrusor contraction insufficiency]. / Esquistosomiasis vesical. Diagnóstico etiológico de la insuficiencia de contracción del detrusor.

This paper reports a case of bladder bilharziasis with histopathological exam and different patterns of urodynamic evaluation. The need for urodynamics is emphasized in order to avoid diagnostic and therapeutic mistakes.