Antimicrobial susceptibility testing profiles of ESBL-producing Enterobacterales isolated from hospital and community adult patients in Blantyre, Malawi.

OBJECTIVE

There is a paucity of data on antimicrobial resistance (AMR) in Malawi. Here we present a study of AMR of extended-spectrum β-lactamases-producing Enterobacterales (ESBL-E) isolated from hospital and community settings in Blantyre, Malawi.

DESIGN AND

METHODS

A cross-sectional study was conducted between March and November 2020, involving 403 adult participants aged ≥18 years. Screening for ESBL-E was performed using CHROMagar ESBL medium. Production of ESBLs was confirmed by a combination disk test method. Antimicrobial susceptibility was tested using the agar disk diffusion method in accordance with the Clinical Laboratory Standards Institute's 2019 guidelines.

RESULTS

The mean resistance rate of ESBL-E to antimicrobial agents tested was 49.2% (range from 1.4%-92%). The highest resistance rates were observed for trimethoprim-sulfamethoxazole (92%), amoxicillin and ceftriaxone (79%), doxycycline (75%) and gentamicin (72%). Carbapenems (meropenem and imipenem) were highly active against isolates. The overall rate of multi-drug resistant (MDR) ESBL-E was 47%. The highest MDR was found in Yersinia enterocolitica (51%) and the least in Serratia spp. (40%).

CONCLUSIONS

We found a high resistance rate of ESBL-E isolates to antimicrobial agents; the majority were MDR. Surveillance systems are recommended to monitor AMR in Malawi.