title: Diagnosis of Schistosoma haematobium by detection of specific DNA fragments from filtered urine samples.
abstract: Definitive diagnosis of Schistosoma haematobium infection in adult patients is a clinically important challenge. Chronically infected adults pass few eggs in the urine, which are often missed when current diagnostic methods are used. In the work presented here, we report on an alternative diagnostic method based on presence of the S. haematobium-specific Dra 1, 121 bp repeat fragment in human urine. A novel method of collecting the urine specimens in the field and filtering them through heavy Whatman No. 3 paper was introduced. After drying, the samples remained viable for several months at room temperature. To test the potential use of this method, 89 urine specimens from school children in Kollo District, Niger, were examined. In all, 52 of 89 (58.4%) were positive for hematuria, 4 of 89 (49.4%) were positive for eggs, and 51 of 89 (57.3%) showed parasite-specific DNA. These were compared with 60 filtered urine specimens obtained from random samples of adults from two study sites in Nigeria, one endemic and one non-endemic for S. haematobium. In the 30 patients from the endemic site, all 10 samples with detectable eggs and 7 of the 20 egg-negative samples were DNA positive. It was concluded that the urine filter paper method was sufficiently sensitive to detect low and cryptic infections, that DNA detection was more sensitive than egg detection, and that the filtration method facilitated specimen collection and transport from the field.
authors.affiliation: Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615 M. Wolfe Street, Baltimore, MD 21205, USA. oibironk@jhsph.edu
authors.forename: Olufunmilola A
authors.initials: OA
authors.lastname: Ibironke
authors.forename: Anna E
authors.initials: AE
authors.lastname: Phillips
authors.forename: Amadou
authors.initials: A
authors.lastname: Garba
authors.forename: Sani M
authors.initials: SM
authors.lastname: Lamine
authors.forename: Clive
authors.initials: C
authors.lastname: Shiff
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D002648:Child; D018509:DNA, Helminth / Q000302:isolation & purification / Q000652:urine; D005260:Female; D005374:Filtration / Q000379:methods*; D006417:Hematuria / Q000175:diagnosis / Q000652:urine; D006801:Humans; D008297:Male; D008875:Middle Aged; D009549:Nigeria / Q000453:epidemiology; D010270:Parasite Egg Count; D016133:Polymerase Chain Reaction; D012548:Schistosoma haematobium / Q000302:isolation & purification*; D012553:Schistosomiasis haematobia / Q000175:diagnosis* / Q000652:urine*; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D055815:Young Adult
chemical_list: D018509:DNA, Helminth