A conventional polymerase chain reaction-based method for the diagnosis of human schistosomiasis in stool samples from individuals in a low-endemicity area

Abstract

The aim of this study was to evaluate the efficacy of a polymerase chain reaction (PCR)-based method to detect Schistosoma mansoni DNA in stool samples from individuals living in a low-endemicity area in Brazil. Of the 125 initial stool samples, 80 were ELISA reactive and eggs were identified in 19 of the samples by parasitological examination. For the PCR evaluations, 56 stool samples were selected and divided into five groups. Groups I-IV were scored negative for S. mansoni eggs by parasitological examination. Groups I and II were ELISA reactive, whereas Groups III and IV were ELISA nonreactive. Groups II and III were positive for other intestinal parasites. PCR testing scored eight samples as positive from these four groups. Group V represented the S. mansoni -positive group and it included ELISA-reactive samples that were scored positive for S. mansoni by one or more parasitological examinations (6/19 were positive by Kato-Katz method, 9/17 by saline gradient and 10/13 by Helmintex®). PCR scored 13 of these 19 samples as positive for S. mansoni . We conclude that while none of these methods yielded 100% sensitivity, a combination of techniques should be effective for improving the detection of S. mansoni infection in low-endemicity areas.

A molecular Approach for Evaluation of Experimental Trials of Anti Schistosomal Vaccination in Murine Models

“…These results were similar to that of Ismail PCR-based diagnosis has been shown to be highly sensitive and specific and should therefore be considered as alternative methods for the diagnosis of S. mansoni infections [35].…”

“…more than two-fold increase in sensitivity. However, PCR failed to detect DNA in six samples that were confirmed to be positive by parasitological examination and ELISA [35]. Pontes et al…”

Advances in the Diagnosis of Human Schistosomiasis

“…Moreover, inhibition of PCR by compounds within fecal samples can be a further problem, although diagnostic accuracy can be increased by combining parasitological or serological testing with PCR (217). With the advent of the loop-mediated isothermal amplification (LAMP) technique, early detection of Schistosoma mitochondrial DNA in stool samples has been demonstrated, as detailed below.…”

Association between allergic responses and Schistosoma mansoni infection in residents in a low-endemic setting in Brazil

“…In particular, control measures have had widely documented benefi cial impacts on disease prevalence, severity and morbidity. However, these infections are still transmitted throughout Ceará state, causing mostly mild infections 21 .…”