Accuracy of real-time polymerase chain reaction to detect Schistosoma mansoni – infected individuals from an endemic area with low parasite loads
Magalhães, Fernanda do Carmo
Resende, Samira Diniz
Enk, Martin Johannes
Coelho, Paulo Marcos Zech
Corrêa, Deborah Aparecida Negrão
Geiger, Stefan Michael
Due to the efforts to control schistosomiasis transmission in tropical countries, a large proportion of individuals from endemic areas present low parasite loads, which hinders diagnosis of intestinal schistosomiasis by the Kato-Katz (KK) method. Therefore, the development of more sensitive diagnostic methods is essential for efficient control measures. The aim was to evaluate the accuracy of a real-time polymerase chain reaction (RT-PCR) to detect Schistosoma mansoni DNA in fecal samples of individuals with low parasite loads. A cross-sectional population-based study was conducted in a rural community (n = 257) in Brazil. POC-CCA® was performed in urine and feces were used for RT-PCR. In addition, fecal exams were completed by 18 KK slides, saline gradient and Helmintex techniques. The combined results of the three parasitological tests detected schistosome eggs in 118 participants (45.9%) and composed the consolidated reference standard (CRS). By RT-PCR, 117 out of 215 tested samples were positive, showing 91.4% sensitivity, 80.2% specificity and good concordance with the CRS (kappa = 0.71). RT-PCR identified 86.9% of the individuals eliminating less than 12 eggs/g of feces, demonstrating much better performance than POC-CCA® (50.8%). Our results showed that RT-PCR is a valuable alternative for the diagnosis of intestinal schistosomiasis in individuals with very low parasite loads.
xmlui.dri2xhtml.METS-1.0.item-citationMAGALHÃES, Fernanda do Carmo et al. Accuracy of real-time polymerase chain reaction to detect Schistosoma mansoni – infected individuals from an endemic area with low parasite loads. Parasitology, v. 147, n. 10, p. 1140-1148, Sept. 2020.
xmlui.dri2xhtml.METS-1.0.item-decsPrimaryEsquistossomose / parasitologia
Esquistossomose / Diagnóstico
Esquistossomose mansoni / parasitologia
Reação em Cadeia da Polimerase em Tempo Real / métodos