Molecular Characterization of Echinococcus multilocularis and Echinococcus granulosus from Cysts and Formalin-Fixed Paraffin-Embedded Tissue Samples of Human Isolates in Northeastern Turkey.

Abstract

Erzurum province of Turkey is known to be highly endemic for alveolar echinococcosis (AE) and cystic echinococcosis (CE). In this study, we confirmed Echinococcus multilocularis cases, searched genetic variations of the isolates, and-for the first time-determined the genotypes of Echinococcus granulosus s.l. infecting humans in the province. A total of 5 alveolar and 106 hydatid cysts as well as 23 formalin-fixed paraffin-embedded (FFPE) samples that were diagnosed as AE were collected from hospitals between 2015 and 2017. Partial sequences of two mitochondrial genes were amplified to detect E. multilocularis and E. granulosus sensu lato with conventional polymerase chain reactions (PCRs) and genotypes confirmed by sequencing. PCR amplification of a partial 12S rRNA gene on an alveolar cyst and FFPE tissue samples yielded the expected bp in 5 cysts and 19 of 23 FFPE samples; all Erzurum E. multilocularis isolates were confirmed by sequencing. Phylogenetic analysis of the isolates indicated that some of them were identical to European isolates, whereas some of them were identical to Asian isolates. Off all hydatid cyst samples, 101 (95.2%) yielded the expected bp (94 with 12S rRNA-PCR and 7 with COI-PCR). Sequence analysis showed that 98 (97%) of them corresponded to the G1 genotype, whereas 3 (3%) corresponded to the G3 genotype. Results of the study emphasize that E. multilocularis isolates of Erzurum, based on short sequencing, are similar to both European and Asian isolates, and the G1 genotype of E. granulosus is the main causative agent of human CE in Erzurum.