Pathogenicity locus determinants and toxinotyping of Clostridioides difficile isolates recovered from Iranian patients

Abstract

Little is known about the toxin profiles, toxinotypes and variations of toxin Clostridioides difficile C (tcdC) in Iranian C. difficile isolates. A total of 818 stool specimens were obtained from outpatients (n = 45) and hospitalized patients (n = 773) in Tehran, Iran, from 2011 to 2017. The 44 C. difficile isolates were subjected to PCR of toxin C. difficile A (tcdA), toxin C. difficile B (tcdB), tcdA 3′-end deletion, toxinotyping and sequencing of the tcdC gene. Thirty-eight isolates (86.36%) were identified as tcdA and tcdB positive, and the remaining six isolates (13.63%) were nontoxigenic. All tcdA- and tcdB-positive isolates yielded an amplicon of 2535 bp by PCR for the tcdA 3′ end. Fourteen (36.84%), seventeen (44.73%) and seven (18.43%) isolates belonged to wild-type, toxin C. difficile C subclone3 (tcdC-sc3) and tcdC-A genotype of tcdC, respectively. Thirty-one isolates (81.57%) belonged to toxinotype 0, and seven isolates (18.42%) were classified as toxinotype V. This study provides evidence for the circulation of historical and hypervirulent isolates in the healthcare and community settings. Furthermore, it was also demonstrated that the tcdC-A genotype and toxinotype V are not uncommon among Iranian C. difficile isolates.

Molecular characterization of pathogenicity locus (PaLoc) and tcdC genetic diversity among tcdAB Clostridioides difficile clinical isolates in Tehran, Iran

“…Sequence analysis of tcdC, predicted that six variants (35/50, 70%) were present in our studied isolates. Recently, Aliramezani et al identi ed two tcdC variants out of 38 isolates including tcdC-sc3 (44.73%) and tcdC-A (18.43%) genotypes [32]. In that study, 36.84% of the isolates were identi ed as a wild-type tcdC genotype which is similar to our ndings.…”

“…The PCR ribotypes of isolates within toxinotype 0 were classi ed into 13 RTs and largely belonged to 001/0, whereas the majority of toxinotype V isolates consisted of the 126/V type. Our ndings resemble a recent study from Iran, in which the toxinotypes 0 (81.57%) and V (18.42%) were reported as the most common toxinotypes [32]. Moreover, another study from diarrheic individuals in an Iranian hospital reported toxinotypes 0 and V as the most prevalent types [33].…”

Temporal Variations in Patterns of Clostridioides difficile Strain Diversity and Antibiotic Resistance in Thailand

“…The toxigenic type A + B + is the most common among toxigenic types [35,36]. However, the presence of tcdA 3 -end deletion has been detected in many clinical isolates, resulting in toxin A-negative C. difficile isolates [37,38]. About half of C. difficile isolates collected during 2006-2009 (THA group) were toxigenic with the highest occurrence of A -B + isolates (Figure 1A).…”

Isolation and characterization of a multidrug-resistant Clostridioides difficile toxinotype V from municipal wastewater treatment plant

“…In this study, the CE-ribotyping profile of this isolate did not correspond to any type of the previously known profiles in the ECDC-Leeds-Leiden reference C. difficile strain dataset (data not shown). However, toxinotyping revealed that this C. difficile belonged to toxinotype V which was also observed in 18.4% of the Iranian C. difficile isolates obtained from stool specimens of patients suffered from CDI [52]. One study was conducted in Iran in 2015 for detection of C. difficile in WWTPs.…”