Validation of a new test for Schistosoma haematobium based on detection of Dra1 DNA fragments in urine: evaluation through latent class analysis

TY - JOUR

T1 - Validation of a new test for Schistosoma haematobium based on detection of Dra1 DNA fragments in urine

T2 - evaluation through latent class analysis

AU - Ibironke, Olufunmilola

AU - Koukounari, Artemis

AU - Asaolu, Samuel

AU - Moustaki, Irini

AU - Shiff, Clive

PY - 2012/1/3

Y1 - 2012/1/3

N2 - BACKGROUND: Diagnosis of urogenital schistosomiasis in chronically infected adults is challenging but important, especially because long term infection of the bladder and urinary tract can have dire consequences. We evaluated three tests for viable infection: detection of parasite specific DNA Dra1 fragments, haematuria and presence of parasite eggs for sensitivity (Se) and specificity (Sp). METHODS: Over 400 urine specimens collected from adult volunteers in an endemic area in Western Nigeria were assessed for haematuria then filtered in the field, the filter papers dried and later examined for eggs and DNA. The results were stratified according to sex and age and subjected to Latent Class analysis. CONCLUSIONS: Presence of Dra1 in males (Se=100%; Sp=100%) exceeded haematuria (Se=87.6%: Sp=34.7%) and detection of eggs (Se=70.1%; Sp=100%). In females presence of Dra1 was Se=100%: Sp=100%, exceeding haematuria (Se=86.7%: Sp=77.0%) and eggs (Se=70.1%; Sp=100%). Dra1 became undetectable 2 weeks after praziquantel treatment. We conclude detection of Dra1 fragment is a definitive test for the presence of Schistosoma haematobium infection.

AB - BACKGROUND: Diagnosis of urogenital schistosomiasis in chronically infected adults is challenging but important, especially because long term infection of the bladder and urinary tract can have dire consequences. We evaluated three tests for viable infection: detection of parasite specific DNA Dra1 fragments, haematuria and presence of parasite eggs for sensitivity (Se) and specificity (Sp). METHODS: Over 400 urine specimens collected from adult volunteers in an endemic area in Western Nigeria were assessed for haematuria then filtered in the field, the filter papers dried and later examined for eggs and DNA. The results were stratified according to sex and age and subjected to Latent Class analysis. CONCLUSIONS: Presence of Dra1 in males (Se=100%; Sp=100%) exceeded haematuria (Se=87.6%: Sp=34.7%) and detection of eggs (Se=70.1%; Sp=100%). In females presence of Dra1 was Se=100%: Sp=100%, exceeding haematuria (Se=86.7%: Sp=77.0%) and eggs (Se=70.1%; Sp=100%). Dra1 became undetectable 2 weeks after praziquantel treatment. We conclude detection of Dra1 fragment is a definitive test for the presence of Schistosoma haematobium infection.

KW - Adult

KW - Animals

KW - DNA, Helminth

KW - Female

KW - Helminth Proteins

KW - Hematuria

KW - Humans

KW - Male

KW - Middle Aged

KW - Nigeria

KW - Parasite Egg Count

KW - Schistosoma haematobium

KW - Schistosomiasis haematobia

KW - Sensitivity and Specificity

KW - Urine

U2 - 10.1371/journal.pntd.0001464

DO - 10.1371/journal.pntd.0001464

M3 - Article

C2 - 22235360

SN - 1935-2727

VL - 6

SP - N/A

JO - PL o S Neglected Tropical Diseases

JF - PL o S Neglected Tropical Diseases

IS - 1

M1 - e1464

ER -