DETECTION OF CARBAPENEMASE-PRODUCING CARBAPENEM-RESISTANT IN BLOOD CULTURE ISOLATES BY MCIM AND ECIM AND ITS SUSCEPTIBILITY TO TIGECYCLINE AND MINOCYCLINE

Abstract

Objective: In this study, we aimed to detect different Carbapenemase-producing carbapenem-resistant Enterobacterales (CREs) in blood isolates by phenotypic, modified carbapenem inactivation methods (mCIM) and amp; EDTA-carbapenem inactivation methods (eCIM), and also to study the susceptibility of these CREs toward Tigecycline and Minocycline. Methods: This prospective study included 100 non-duplicate Enterobacterales organisms isolated from 250 blood samples positive for Enterobacterales that showed resistance to carbapenem (Imipenem). The isolates were identified by conventional routine biochemical tests. CRE isolates were screened for Carbapenemase production by the Clinical and Laboratory Standards Institute (CLSI)-recommended, mCIM and eCIM for evidence of the production of matello-beta-lactamase. Antimicrobial susceptibility for Tigecycline and Minocycline drugs was tested by the disk diffusion method on Mueller–Hinton agar according to CLSI guidelines, and susceptibility patterns were recorded. Clinical diagnosis data were collected from the requisition forms sent to our laboratory during test procedures. Results: Out of 100 (40%) CRE isolates tested for mCIM, 34 samples showed positive results for the Carbapenemase enzyme. Among the mCIM-positive isolates, Klebsiella spp. showed the highest prevalence of 58.8% (20/34). While among mCIM-positive isolates (22/34), 64.7% were positive for eCIM (Matello beta-lactamase producer). Maximum samples had been received from the NICU ward from patients diagnosed with early-onset sepsis; 41.2% of these were Carbapenemase-producing Enterobacterales. Among CRE isolates, 86 isolates were susceptible to Tigecycline and 24 isolates were susceptible to Minocycline. 70 CRE isolates were susceptible to Tigecycline but resistant to minocycline, and all CRE isolates resistant to Tigecycline were not susceptible to Minocycline.