Resistance, Persistence and Tolerance Significance of MDR Nosocomial Bacterial Infections in ICUs in Relation to MBC/MIC

Document Type : Original Article

Authors

1 Faculty of Science, Seuz Canal Univerisity, Seuz, Egypt.

2 New Cairo Police Hospital, Cairo, Egypt

Abstract

NOSOCOMIAL infections are a major challenge, as one third of yearly admissions estimated as deaths. In intensive care units (ICUs), Gram-negative pathogens are responsible for the majority of these deadly infections. Multidrug resistance (MDR) in the seorganisms has been attributed to production of modified enzymes responsible of elevated MICs and MBC/MICs putting them in the transient stages for persistence and tolerance. Bacterial cells those can survive high doses of antibiotics comprise a subpopulation of persistent but not resistant cells. Bacterial isolates (326) were collected from nosocomial infections via microbiology laboratories of police hospitals in Cairo. Frequency-wise, it was found that Escherichia is the most frequent (155), Pseudomonas (96), Staphylococcus (34), Klebsiella (24), Proteus (16) while Citrobacter is the least frequent (1). Pseudomonas, Klebsiella, Proteus and Citrobacter showed the highest MDRs, with the highest MICs in a descending order. Results clearly indicated the high risk of the two Pseudomonas aeruginosa from sputum and urine persisting (inhibited but not killed) against MICs 3 tested antibiotics; CRO, AMC and FEB. It is highly recommended here to run tests for MBC/MICs to choose the antibiotic with least MBC/MIC ratio; less than four, in order to reduce the transient persistent and/ or tolerant stages.

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