Background: For judicious use of reserve drugs, timely detection of carbapenemases is essential. While molecular tools are gold standard for detection of these enzymes, many laboratories have limited access to them. This study focused on evaluating in-house and commercial phenotypic tests for detection of OXA-48 in particular, KPC and NDM in general in K. pneumoniae, the predominant extremely drug-resistant pathogen in Oman. Methods: Eighty GeneXpert/PCR confirmed (40 OXA-48, twenty KPC and NDM each) and 37 whole-genome-sequenced (25 OXA-232, 6 KPC-2 plus NDM-1 and NDM-5 each) K. pneumoniae were subjected to screening by temocillin (30 μg disk MAST Diagnostica, Germany) and D71C (MASTDISCS^®). Isolates resistant to temocillin (<11mm) and D71C were subjected to four tests -one in-house (OXA-48 disk test) and three commercial phenotypic tests (i) The MASTDISCS^® Combi (D72C) (MAST Group Ltd., UK). (ii) The MASTDISCS^® Combi (D73C) (MAST Group Ltd., UK) and (iii) Immunochromatographic assay (ICT); KPC/IMP/NDM/VIM/OXA-48 Combo test kit (Medomics, China for detection of OXA-48 like, KPC and NDM carbapenemases. Results: Temocillin exhibited good sensitivity and specificity (100% and 97.50%) compared to D71C (70% and 100%). Among the confirmatory tests, the in-house OXA-48 disk test had 92.50% sensitivity and 100% specificity, while the commercial MAST DISC tests D72C D73C and ICT had 97.50%, 95.00% and 100% sensitivity and 100%, 91.67% and 95% specificity respectively. Conclusion: Temocillin disc test is a good screening tool. With high sensitivity and specificity, ease of performance, short turnaround time and low cost, we recommend ICT for routine diagnostic use. In resource constrained centres, OXA-48 disk test is an excellent alternative with high sensitivity and specificity.

Background: While mapping Escherichia coli susceptibility in community acquired simple UTIs across 38 centres, DASH to Protect Antibiotics, (https://dashuti.com/), a multiregional study also assessed impact of socio-economic conditions and climate on antimicrobial susceptibility. Methods: The centres were located in the Indian subcontinent, Middle East, North and West Africa, Eurasia, Europe, and North America. Harmonic means were used for comparative analysis of the antimicrobial susceptibility of E. coli in simple cystitis. Kruskal-Wallis test was utilized to compare susceptibility means between the antimicrobials and the GDP. A two-way ANOVA to simultaneously analyzed the impact of the antimicrobials and GDP on the proportion of susceptible E. coli while adjusting for variables (low and high temperature, humidity and population density per sqkm). Findings: Antimicrobial susceptibility varied between regions and within large countries like India and Pakistan. Nitrofurantoin (89%) and fosfomycin (96%) emerged as the most effective antimicrobials. In majority of the centres, susceptibility to other oral antimicrobials was low: cotrimoxazole.