Publikationsdatenbank

Isolation procedure for CP E. coli from caeca samples under review towards an increased sensitivity (2021)

Art

Zeitschriftenartikel / wissenschaftlicher Beitrag

Autoren

Pauly, Natalie

Klaar, Yvonne

Skladnikiewicz-Ziemer, Tanja

Juraschek, Katharina

Grobbel, Mirjam

Hammerl, Jens André

Hemmers, Lukas

Käsbohrer, Annemarie

Schwarz, Stefan (WE 7)

Meemken, Diana (WE 8)

Tenhagen, Bernd-Alois

Irrgang, Alexandra

Quelle

Microorganisms : open access journal

Bandzählung: 9

Heftzählung: 5

Seiten: Artikel 1105

ISSN: 2076-2607

Sprache

Englisch

Verweise

URL (Volltext): https://www.mdpi.com/2076-2607/9/5/1105

DOI: 10.3390/microorganisms9051105

Pubmed: 34065518

Kontakt

Institut für Lebensmittelsicherheit und -hygiene

Königsweg 69
14163 Berlin
+49 30 838 62551 / 52790
lebensmittelhygiene@vetmed.fu-berlin.de / fleischhygiene@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Due to the increasing reports of carbapenemase-producing Enterobacteriaceae (CPE) from livestock in recent years, the European Reference Laboratory for Antimicrobial Resistances (EURL-AR) provided a protocol for their recovery from caecum and meat samples. This procedure exhibited limitations for the detection of CPE with low carbapenem MIC values. Therefore, it was modified by a second, selective enrichment in lysogeny broth with cefotaxime (CTX 1 mg/L) and with meropenem (MEM 0.125 mg/L) at 37 °C under microaerophilic conditions. By Real-time PCR, these enrichments are pre-screened for the most common carbapenemase genes. Another adaptation was the use of in-house prepared MacConkey agar with MEM and MEM+CTX instead of commercial selective agar. According to the EURL-method, we achieved 100% sensitivity and specificity using the in-house media instead of commercial agar, which decreased the sensitivity to ~75%. Comparing the method with and without the second enrichment, no substantial influence on sensitivity and specificity was detected. Nevertheless, this enrichment has simplified the CPE-isolation regarding the accompanying microbiota and the separation of putative colonies. In conclusion, the sensitivity of the method can be increased with slight modifications.