Schistosoma haematobiuminfection in Nigeria

Kidney disease among children in sub-Saharan Africa: systematic review

The global burden of kidney disease is increasing, and several etiologies first begin in childhood. Risk factors for pediatric kidney disease are common in Africa, but data regarding its prevalence are lacking. We completed a systematic review of community-based studies describing the prevalence of proteinuria, hematuria, abnormal imaging, or kidney dysfunction among children in sub-Saharan Africa (SSA). Medline and Embase were searched. Five hundred twenty-three references were reviewed. Thirty-two references from nine countries in SSA were included in the qualitative synthesis. The degree of kidney damage and abnormal imaging varied widely: proteinuria 32.5% (2.2-56.0%), hematuria 31.1% (0.6-67.0%), hydronephrosis 11.3% (0.0-38.0%), hydroureter 7.5% (0.0-26.4%), and major kidney abnormalities 0.1% (0.0-0.8%). Serum creatinine was reported in four studies with insufficient detail to identify the prevalence renal dysfunction. A majority of the studies were performed in Schistosoma haematobium endemic areas. A lower prevalence of kidney disease was observed in the few studies from nonendemic areas. Published data on pediatric kidney disease in SSA are highly variable and dependent on S. haematobium prevalence. More community-based studies are needed to describe the burden of pediatric kidney disease, particularly in regions where S. haematobium infection is nonendemic.

[Dynamic transmission of Schistosoma by Biomphalaria pfeifferi in the region of Man in Côte d'Ivoire]

Intestinal schistosomiasis by Schistosoma mansoni is a parasitary affection transmitted in West Africa by the mollusc Biomphalaria pfeifferi. Transmission dynamic of schistosomiasis by Biomphalaria pfeifferi has seldom been investigated in Côte d'Ivoire. In the framework of a research project on the epidemiology of schistosomiasis in the natural forest ecosystems, this study was performed longitudinally over a period of three years in Man region, in western Côte d'Ivoire. The trial set up from 1986 to 1989 and the project was funded by the World Health Organization. The general objective is to design a strategy of schistosomiasis control based on chemotherapy. The approach aims at interrupting or considerably reducing the reinfections, prolonging in that way the duration of the positive effects of the chemotherapy. The specific objectives assigned to the work consisted in studying the dynamic of the B. pfeifferi population and the infection of B. pfeifferi. To achieve our objectives, diverse methods (i: the molluscs sampling by two prospectors during 15 minutes per study site and ii: individual isolation of molluscs in test tubes with 5 or 10 mL of filtered water and exposure to light) have been used. They enabled us in the sampling of the intermediary host molluscs of Schistosoma and seek their infections. The results show that apparent high densities of B. pfeifferi can be observed at the end of the dry season and at the beginning of rainy seasons. In addition, the variation of relative abundance of intermediary host molluscs of Schistosoma is significantly influenced by rainfall and the system of water ways. The period of transmission of the infection to man is six months at Gueupleu village and ten months at Botonguiné village. In order to optimize the effect of chemotherapy in these sites of transmission characterized by a high level of endemy (68 %), an extreme mobility of human populations and a multiplicity of contamination sites, this study should not only take into account the geographic space of the illness, but also it should eventually associate with a molluscicide action and/or a sanitary education through the teaching of primary health care.

Participatory action research: community diagnosis and intervention in controlling urinary schistosomiasis in an urban community in Ibadan, Nigeria

Schistosomiasis is second only to malaria and is endemic in Nigeria. It has been reported that the infection is more prevalent, irrespective of gender, in the age group 5 to 14 years. It is least among the age group 26 and 55 and occurs mostly in the rural areas in the country. The infection is spreading from the rural areas to various urban communities, particularly the agricultural and fishing populations. In Ibadan, capital of Oyo State in southwestern Nigeria where the focus of this study is made, the infection has been reported among children and adolescents in six Local Government Areas. Students of Advanced Diploma in Health Education (ADHE) of the Department of Health Promotion and Education, during a community diagnosis exercise among primary schools in two communities in Ibadan, met with this problem. The purpose of this study is to mobilize the affected communities, with both internal and external resources through a participatory-action process, to combat the infection which is one of their major problems. Since the providence of schistosomiasis in target communities is age related, investigations were concentrated in 17 Primary Schools in the two communities. The investigation involved laboratory confirmation by collecting 147 urine samples from a total population of 676 children and examining them microscopically for the schistosoma ova. In addition, the quality of stream water and their vector presence were assessed. The key intervention strategy used was community mobilization of both internal and external resources of targeted communities. The striking outcome of the intervention study is that the outbreak of schistosomiasis in the communities was formally reported to the Federal Ministry of Health and the Oyo State Ministry of Health. All infected pupils were treated, the long awaited water scheme to replace the broken pipes was completed, and two new water supply schemes were implemented by the communities. Further, the communities displayed sign boards prohibiting community members from fetching water from "Dandaru" river for daily domestic needs. It is concluded that the combined efforts of all the actors helped the community to enjoy improved water supply and reduced their exposure to infection from the stream, which was the source of the infection.

Urinary schistosomiasis among schoolchildren in Ibadan, an urban community in south-western Nigeria

The current status of urinary schistosomiasis was assessed in Ibadan, an urban community in south-western Nigeria. Of 1331 children examined for eggs of S. haematobium in their urine, 17.4% were infected. Prevalence in postprimary schoolchildren was significantly (P < 0.01) higher (22.4%) than in primary schoolchildren (12.0%). Intensity of infection based on geometric mean egg count per 10 ml of urine was also higher in postprimary (36.7 eggs/10 ml urine) than primary pupils (29.9 eggs/10 ml urine). Boys had a significantly (P < 0.01) higher infection rate (24.1%) than girls (8.5%), and the intensity of infection was also higher (P < 0.01) in males (39.0 eggs/10 ml urine) than in females (22.1 eggs/10 ml urine). The overall geometric mean intensity of infection was highest (38.8 eggs/10 ml urine) in the 11-15 years age group. 42% of infected children excreted > 50 eggs/10 ml urine. 2.2% excreted S. mansoni eggs in urine. Water contact activities were more frequent (P < 0. 01) in males (31.8%) than females (38.2%). Nine species of snails were encountered, with B. (p) globosus being the the most abundant and widespread. These results show that urinary schistosomiasis is still being actively being transmitted in Ibadan.

A review of the literature on the use of ultrasonography in schistosomiasis with special reference to its use in field studies

This review presents an outline of the pathology resulting from Schistosoma haematobium infections, and the ways in which the lesions can be investigated. The use of ultrasonography is covered in detail. Ultrasonography can provide direct information about lesions in internal organs, and thus provide information about patterns of morbidity and about the regression of pathological changes after treatment. The method has the advantages that it is non-invasive, and is also relatively inexpensive and can be used under field conditions. Ultrasonography has already been used in a number of epidemiological studies in areas where S. haematobium is endemic. The method has proved to be feasible and useful. However, the methodology used for ultrasound studies has varied considerably, so that it is difficult to make valid comparisons between results obtained in different places or at different times. A standardized methodology for making observations and recording the results is needed if the full potential benefit of using ultrasound in the monitoring of schistosomiasis control projects is to be realised. The correlation of results obtained using ultrasound with the results of clinical, parasitological and other observations has been investigated in a number of studies, but many questions remain to be answered.

Urinary schistosomiasis in Maiduguri, north east Nigeria

From January to December 1983, 12,207 specimens of urine were examined for ova of Schistosoma haematobium and 753 (6.17%) were positive. From this group, 44 adult patients were investigated for urinary tract abnormalities. Haematuria was the commonest presenting symptom (81.8%) followed by lower abdominal pain (77.3%) and dysuria (68.2%). Urinalysis revealed proteinuria in 55.5%, leucocyturia in 90.9% and microhaematuria in 88.6% of patients. Twenty-four hour protein excretion ranged from 230 mg to 2.2 g (mean 960 mg). Serum creatinine was raised in one patient (2.2 mg dl-1), Urological abnormalities included calcification of the bladder in 36.4%, ureteric strictures and dilatations in 65.9%, hydronephrosis in 9.1%, squamous cell carcinoma of the bladder in 4.5%, vesicle calculus in 2.3%, and multiple granulomatas in the bladder in 2.3% of the patients. The results of the study suggest that a sizeable population of this area is at risk of developing urological complications and consequently chronic renal insufficiency.

Ultrasonographical aspects of urinary schistosomiasis: assessment of morphological lesions in the upper and lower urinary tract

Ultrasonographic evaluation of 213 patients with urinary schistosomiasis in different age groups was performed in an endemic area of the Democratic Republic of Congo. The results were compared with 94 age matched controls without urinary schistosomiasis. In patients the bladder showed thickening of the wall, polypoid lesions of the mucosa and bladder wall, calcifications and urinary retention. Urinary tract obstruction, predominantly unilateral, was demonstrated. The lesions increased in severity with the intensity of infection, parallel to an increase in ova excretion. Children aged between 8 and 19 years were most severely affected. Pathological lesions of the upper urinary tract were rare in patients over 25 years of age. The combination of morphological abnormalities was interpreted as being specific for urinary schistosomiasis as they did not occur in the control group. It is suggested that real time ultrasonography may be used to identify morphological lesions in urinary schistosomiasis.

Renal disease due to schistosomiasis of the lower urinary tract

The literature concerning renal impairment and damage due to vesical schistosomiasis has been reviewed, with emphasis on radiologic, biochemical, and renographic studies of renal function in affected persons. Presently available evidence suggests that infections due to S. haematobium constitute an important public health problem because they are widely prevalent. A high proportion of affected persons suffer renal impairment and damage due to obstructive uropathic lesions in the lower urinary tract and, probably, through direct immunologic involvement of the kidney. It is therefore important that efforts should be intensified to better define the size and scope of the problem, and to control the disease.