Performance of the point-of-care circulating cathodic antigen (POC-CCA) urine cassette test for follow-up after treatment of S. mansoni infection in Eritrean refugees

• Published in: Travel medicine and infectious disease 2019-03, Vol.28, p.59-63
• Main Authors: Neumayr, Andreas, Chernet, Afona, Sydow, Véronique, Kling, Kerstin, Kuenzli, Esther, Marti, Hanspeter, Paris, Daniel H., Nickel, Beatrice, Labhardt, Niklaus D.
• Format: Article
• Language: English
• Subjects: Adult; Animals; Antigens; Blood & organ donations; Drug resistance; Eggs; Eritrea; Feces - parasitology; Female; Follow-Up Studies; Hematologic Tests - standards; Humans; Immunoglobulins; Infections; Infectious diseases; Laboratories; Male; Medical screening; Methods; Microscopy; Migrants; Parasites; Parasitic diseases; Point-of-Care Systems - standards; Praziquantel - therapeutic use; Procedures; Refugees; Reproducibility of Results; Schistosoma mansoni; Schistosomiasis; Schistosomiasis mansoni - blood; Schistosomiasis mansoni - diagnosis; Schistosomiasis mansoni - drug therapy; Schistosomiasis mansoni - urine; Screening; Sedimentation & deposition; Sensitivity and Specificity; Serology; Specificity; Switzerland; Testing; Travel medicine; Tropical diseases; Urinalysis - standards; Urine; Young Adult
• ISSN: 1477-8939; 1873-0442
• DOI: 10.1016/j.tmaid.2018.09.004

Point-of-care circulating cathodic antigen (POC-CCA) urine cassette testing has become a popular approach to screen for Schistosoma infection. Since the test is also increasingly used for following-up of treatment success, we assessed the assay's diagnostic accuracy after praziquantel treatment of S. mansoni infection among Eritrean refugees in Switzerland. In our preceding study, 107 asymptomatic Eritrean refugees in Switzerland were screened for schistosomiasis by stool microscopy, serology, and POC-CCA urine testing. Individuals screened positive by any method were treated with praziquantel and invited for a follow-up visit, repeating the same diagnostic procedures one year after treatment. The POC-CCA baseline and follow-up results were analyzed against the ‘baseline microscopy positive cases’ (= the most reliably true positive cases) and the ‘baseline microscopy plus serology negative cases at baseline and follow-up’ (= the most reliably true negative cases). Complete diagnostic baseline and follow-up sampling was available from 48 participants. Compared to most reliably true positive cases at baseline, POC-CCA testing had a sensitivity of 90%. Compared to most reliably true negative cases, POC-CCA testing had a specificity of 73.9%. We conclude that the POC-CCA urine test is valuable for screening but its use is not suitable for routine follow-up after treatment.