Evaluation of circulating cathodic antigen (CCA) strip for diagnosis of urinary schistosomiasis in Hassoba school children, Afar, Ethiopia

Abstract

Summary :A total of 206 urine samples collected from Hassoba Elementary schoolchildren, Afar, Ethiopia, a low Schistosoma haematobium endemic setting, was diagnosed to evaluate the performance of CCA strip using double references, urine filtration technique and urinalysis dipstick (Combur 10 Test ® ) that detect schistosome eggs and blood in urine, respectively. The former was used as a gold standard reference method. Sensitivity, specificity, positive and negative predictive values for the CCA were 52 %, 63.8 %, 56.7 % and 59 % respectively, with reference to urine filtration technique whereas these parameters were 50.4 %, 62.4 %, 55.6 % and 57.5 % respectively, with reference to Combur 10 Test ® . 47 S. haematobium egg-positive children were found negative by CCA strip while 38 egg-negative children were found positive by CCA strip. Moreover, among the pre-tests done in duplicate, inconsistent results were also recorded. Assays were also compared with regard to the cost of equipment and reagents, speed and simplicity of use. Though CCA strip was found to be rapid and could be performed with minimal training, it was found to be expensive (US $ 4.95 per test) to use it for large-scale field use even if its diagnostic value would have been satisfactory. Further development and standardization of the CCA strip are required for its applicability for field use. It is also recommended that its cost per strip should be substantially cut down if it is to be used in poor schistosomiasis endemic countries. Résumé

Validation of a Point-of-Care Circulating Cathodic Antigen Urine Cassette Test for Schistosoma mansoni Diagnosis in the Sahel, and Potential Cross-Reaction in Pregnancy

“…In contrast, most of the previously published studies that validated the POC-CCA urine cassette test for the diagnosis of S. mansoni in schistosomiasisendemic areas focused on school-aged children. 5,[19][20][21][22][23][24][25][26][27] Positive POC-CCA urine cassette test results in males and females with negative stool microscopy may be explained by the fact that we only examined a single stool sample per participant, and hence, we might have missed individuals with low infection intensity. 28 Interestingly, we found three positive POC-CCA urine cassette tests among pregnant women with negative stool microscopy.…”

Cost Analysis of Tests for the Detection of Schistosoma mansoni Infection in Children in Western Kenya

“…12,13 The POC-CCA assay is commercially available through Rapid Medical Diagnostics (Pretoria, South Africa), and has been evaluated for sensitivity, specificity, and ease of use in a number of settings. [14][15][16][17][18][19] However, there has been concern that the cost of the POC-CCA assay may be a barrier to widespread adoption of this technique for schistosomiasis control programs 14,16,17,20 ; therefore, there is a need for a comprehensive evaluation of the cost-effectiveness of the POC-CCA technique in relation to other available tests. 13 Although the cost of the materials and equipment are commonly cited as expenses, other cost contributions such as labor and transportation are rarely discussed.…”

“…13 Although the cost of the materials and equipment are commonly cited as expenses, other cost contributions such as labor and transportation are rarely discussed. 17,20 Thus, we have pursued a comprehensive assessment of cost-effectiveness to determine all of the expenses associated with each assay relative to their effectiveness.…”

Diagnosing schistosomiasis: where are we?

“…To date, currently available CCA tests have been shown to have moderate to good reliability in detecting S. mansoni 54,[61][62][63][64][65] but poor performance in detecting S. haematobium 61,[66][67][68][69] . Recently, the Bill & Melinda Gates Foundation sponsored evaluation studies on the accuracy of the urine CCA tests for determining schistosomiasis prevalence in young children in African countries.…”