Accuracy of urine circulating cathodic antigen test for the diagnosis of Schistosoma mansoni in preschool-aged children before and after treatment

PLoS Negl Trop Dis. 2013;7(3):e2109. doi: 10.1371/journal.pntd.0002109. Epub 2013 Mar 21.

Abstract

Background: The Kato-Katz technique is widely used for the diagnosis of Schistosoma mansoni, but shows low sensitivity in light-intensity infections. We assessed the accuracy of a commercially available point-of-care circulating cathodic antigen (POC-CCA) cassette test for the diagnosis of S. mansoni in preschool-aged children before and after praziquantel administration.

Methodology: A 3-week longitudinal survey with a treatment intervention was conducted in Azaguié, south Côte d'Ivoire. Overall, 242 preschoolers (age range: 2 months to 5.5 years) submitted two stool and two urine samples before praziquantel administration, and 86 individuals were followed-up posttreatment. Stool samples were examined with duplicate Kato-Katz thick smears for S. mansoni. Urine samples were subjected to POC-CCA cassette test for S. mansoni, and a filtration method for S. haematobium diagnosis.

Principal findings: Before treatment, the prevalence of S. mansoni, as determined by quadruplicate Kato-Katz, single CCA considering 'trace' as negative (t-), and single CCA with 'trace' as positive (t+), was 23.1%, 34.3% and 64.5%, respectively. Using the combined results (i.e., four Kato-Katz and duplicate CCA(t-)) as diagnostic 'gold' standard, the sensitivity of a single Kato-Katz, a single CCA(t-) or CCA(t+) was 28.3%, 69.7% and 89.1%, respectively. Three weeks posttreatment, the sensitivity of a single Kato-Katz, single CCA(t-) and CCA(t+) was 4.0%, 80.0% and 84.0%, respectively. The intensity of the POC-CCA test band reaction was correlated with S. mansoni egg burden (odds ratio = 1.2, p = 0.04).

Conclusions/significance: A single POC-CCA cassette test appears to be more sensitive than multiple Kato-Katz thick smears for the diagnosis of S. mansoni in preschool-aged children before and after praziquantel administration. The POC-CCA cassette test can be recommended for the rapid identification of S. mansoni infections before treatment. Additional studies are warranted to determine the usefulness of POC-CCA for assessing drug efficacy and monitoring the impact of control interventions.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anthelmintics / therapeutic use
  • Antigens, Helminth / urine*
  • Child, Preschool
  • Clinical Laboratory Techniques / methods*
  • Cote d'Ivoire
  • Drug Monitoring / methods*
  • Feces / parasitology
  • Female
  • Humans
  • Infant
  • Longitudinal Studies
  • Male
  • Parasitology / methods*
  • Point-of-Care Systems
  • Praziquantel / therapeutic use
  • Schistosoma mansoni / isolation & purification*
  • Schistosomiasis mansoni / diagnosis*
  • Schistosomiasis mansoni / drug therapy
  • Sensitivity and Specificity

Substances

  • Anthelmintics
  • Antigens, Helminth
  • Praziquantel

Grants and funding

This study received financial support from the Carolito Foundation for a PhD fellowship granted to JTC. The research of SK is supported by a sub-award (no. RR 374-053/4787996) from the University of Georgia Research Foundation, which is awarded by the Bill & Melinda Gates Foundation (prime award no. 50816). The research pursued by EKN and JU is financially supported by Fairmed and the Swiss National Science Foundation (project no. IZ70Z0_123900). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.