Modified Carbapenem Inactivation Method (mCIM) for detection of carbapenemase production in Klebsiella spp

Abstract

Background: Urinary tract infection (UTI) is one of most common pediatric infections. The study was conducted with an aim to assess the etiological agents, antimicrobial resistance, their risk factors and clinical significance in pediatric UTI cases.Methods and materials: This is a cross-sectional study conducted at Department of Microbiology and Infectious Diseases for 1 year (January to December 2018). A total of 4020 pediatric patients <14 years old, suspected to have UTI, were included in the study. Clinical data was obtained from software and enquiry with patients whenever feasible; standard microbiological guidelines were followed for laboratory testing. Chi-square test was applied for comparison of categorical variables. P value less than 0.05 was considered as statistically significant.Results: Of the 4020 children with suspected UTI, 724 (18%) were culture positive. Escherichia coli was the most common etiological agent (55% n = 402), followed by Enterococcus faecalis (17%, n = 120), and Klebsiella pneumoniae (9%, n = 65). Among total isolates, 32% (n = 231) were multi-drug resistant (MDR) while 35% (192) of gram-negative bacilli were extended-spectrum b lactamase (ESBL) producers. Multidrug resistance and ESBL production occurred more frequently in previously hospitalized patients (p value 0.0001 and 0.02), patients with longer duration of fever (p value 0.03 and 0.01) and higher recurrence rate (p value 0.001 and 0.001). ESBL production was observed most commonly in neonates (40%), followed by infants (32%). Degree of antimicrobial resistance was significantly higher in ESBL producer isolates as compared to non-producers. Amikacin resistance was observed in 22% of ESBL producer isolates as compared to 14% in non-producers (p value 0.01). Similar pattern of resistance were observed for other antimicrobials.Conclusion: High-level antimicrobial resistance was observed in pediatric UTI with alarming incidence superbugs MDR and ESBL. Previous hospitalization, longer duration of fever and recurrence is significantly associated with increase in MDR and ESBL production. Regular antimicrobial surveillance should be carried out and judicial use of antimicrobials based on susceptibility reports when available and local antimicrobial resistance data should be encouraged for the optimal management of pediatric UTI.

Outcomes in Oxacillinases β-Lactamases (OXA-48) and New Delhi Metallo-β-Lactamase (NDM-1)-Producing, Carbapenem-Resistant Klebsiella Pneumoniae Isolates Obtained From Bloodstream Infections

“…Studies have reported a sensitivity and specificity of mCIM ranging between 96.1-99% and 92.9-100%, respectively, for detection of CRKP as compared to the molecular tests [ 16 , 17 ]. In contrast, in the present study, the phenotypic mCIM test was found to have only moderate sensitivity (77.6%) and negative predictive value (78.9%) as compared to the conventional PCR, and all the phenotypically missed cases produced OXA-48 type carbapenemases singly or in combination with NDM.…”