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USE OF PORTABLE ULTRASONOGRAPHY AND URINE-ALBUMIN ASSAYS FOR DETECTION OF URINARY TRACT PATHOLOGIES (UTPs) ASSOCIATED WITH URINARY SCHISTOSOMIASIS ON UNGUJA ISLAND, ZANZIBAR J.C. Sousa Figueiredo1, A.F. Mgeni2, M.-G. Basáñez1, D. Rollinson3, J.R. Stothard3 1Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, UK 2Helminth Control Laboratory Unguja, Helminth Control Programme, Zanzibar 3Department of Zoology, Natural History Museum, London SW7 5BD, UK Key Findings • Prevalence of urinary schistosomiasis was 36% [CI95 28-44%] in schools and 47% [CI95 33-61%] in Chaani Health Centre • In the population surveyed at the health centre, UTPs were more common (64%) than in school-aged children (40%) • Bladder pathologies accounted for the majority of UTPs identified in the population (90%) • Raised urine-albumin concentration (≥40mg/l) was found to be indicative of: • Infection (OR=3.7, p=0.11) and microhaematuria (OR=135.3, p<0.000) in school-aged children (n=132)* • Bladder pathologies (OR=8.4, p<0.01) in male adults (n=47)* * Model selected by stepwise (AIC) logistic regression controlling for sex, age, and location URINARY SCHISTOSOMIASIS AND ZANZIBAR Schistosoma haematobium infection, the cause for urinary schistosomiasis, is responsible for a variety of debilitating conditions, including urinary tract pathologies (UTPs). Ultrasonography is commonly used to detect UTPs, however new non-invasive, rapid epidemiological assessment tools need to be investigated. Objective: To identify associations between excreted urine-albumin, a known proxy of S. haematobium infection in children, and UTPs, as detected in ultrasonography FIELD WORK • Three schools from Unguja Island (Chaani, Kinyasini, and Mwera) were surveyed (n = 140 children aged 9 to15 yr) • A cross-sectional study of adult males (n = 47) attending Chaani Health Centre was also conducted TWO PROPOSED MODELS EXPLAINING EXCRETED URINE-ALBUMIN AETIOLOGY School-aged children [top/left]: • Pairs of S. haematobium worms migrate to the vesical plexus and veins draining the ureters URINE-ALBUMIN AND ULTRASONOGRAPHY • In school-aged children, raised urine-albumin levels were found indicative of positive S. haematobium egg counts (OR=29.5, p<0.001) [not in adults, p=0.58] • In school-aged children, prevalence of UTPs was found associated with positive S. haematobium egg counts (OR=5.4, p<0.001) [not in adults, p=0.56] • Egg production commences; eggs pass from the lumen of blood vessels; many penetrate the bladder mucosa being shed in the urine (blue arrows) • Tissue damage and subsequent haemorrhage (red arrow) follow, increasing albumin concentration in urine Urine samples - haematuria Adults [top/right]: • Long term pathologies (particularly bladder MORBIDITY Urine-albumin photometer Infection was found associated with pain on urination in children (OR=3.9, p<0.01) and adult males (OR=9.9, p<0.01) lesions) are induced by high burdens and exposure to S. haematobium • Through these lesions, albumin-rich bloodserum infiltrates the bladder (orange arrows) Raised Microhaematuria Macrohaematuria UTPs urine-albumin Schools 41% 8% 40% 34% Health Centre 60% 4% 64% 28% Ultrasonograph of bladder • Infiltration leads to increase in urinealbumin levels without the direct influence of S. haematobium egg excretion and without causing haematuria URINE-ALBUMIN AS A RAPID EPIDEMIOLOGICAL ASSESSENT TOOL FOR UTPs • Despite ongoing efforts to control S. haematobium, UTPs are still common in school-aged children and adults • Future work should be directed at monitoring the extent to which UTPs improve during control programmes • Urine-albumin assays can be used as a rapid, field-applicable screening tool for assessing UTP prevalence Acknowledgements: Dr Amadou Garba (SCI, Niger); Mr Khamis Adulrahman Simai, Mrs Salma Suleiman Seif, Mr Mahmoud Badru Ali and Mr Masoud Hassan Juma (Unguja ultrasonographers); Health Foundation, UK (DR, JRS); MRC (M-GB); Part of the MSc in Modern Epidemiology, Imperial College – London (JCSF)