Evaluation of a duplex real-time PCR in human serum for simultaneous detection and differentiation of Schistosoma mansoni and Schistosoma haematobium infections - cross-sectional study
Background: We evaluated a one-tube multiplex real-time PCR targeting DNA of Schistosoma haematobium
complex and S. mansoni complex in serum samples obtained at different German diagnostic centers.
Methods: Simplex real-time PCR protocols for the detection of the multi-copy DNA-repeats Dra1 of
S. haematobium complex and Sm1-7 of S. mansoni complex in serum were combined to a new one-tube multiplex
format. The new PCR was subjected to full validation including evaluation in a diagnostic real-life setting with
travelers and migrants. PCR results were compared with those of stool and urine microscopy, serology, and
circulating cathodic antigen (CCA) rapid diagnostic tests in urine. Sensitivity and specificity of the diagnostic
approaches were analyzed using latent class analysis (LCA).
Results: LCA assessment indicated sensitivity and specificity of 94.9% and 98.4%, respectively, for serum PCR if
serology was included in the calculation, and 100% and 95.6%, respectively, if serology was not included as a
parameter not necessarily associated with active infection. Agreement between the compared diagnostic procedures at genus level was fair (kappa 0.273) if serology was included and moderate (kappa 0.420) if serology
was not included.
Discussion: The PCR assay proved to be highly reliable for the diagnosis of schistosomiasis in travelers and
migrants
