2024/12/15 by Z. Hamzaoui, A. Slim And I. Boutiba Ben Boubaker, E. Maamar +3
#Acinetobacter baumannii #New Delhi metallo-β-lactamase #carbapenems #resistance.
paper · doi:10.71612/pist-aipt-189525
Carbapenem-resistant Acinetobacter baumannii is considered as a major health problem. In the present study, we report the first description of carbapenemresistant A. baumannii carrying blaNDM-1 gene in association with blaOXA-58 in a Tunisian neonatal unit in April 2014. A 2-day-old baby was admitted to the neonatal ward for maternal fetal infection. Blood culture and peripheral neonate specimens were analyzed. Bacterial species were identified using the API20NE system and confirmed by amplification of blaOXA-51 gene. Antimicrobial susceptibility testing was determined by disk diffusion method. MICs of carbapenems, colistin and tigecycline were evaluated using E-test strips. Carbapenemase production was evidenced by the modified Hodge test (MHT) and screening for the Métallo- β-Lactamase (MBL) production was evaluated by EDTA-disk synergy test. PCR and sequencing were performed to detect carbapenemase-related genes and extended-spectrum-lactamases. Transfer of the blaNDM-1 gene was attempted by conjugation or electro-transformation. Culture from gastric fluid revealed a carbapenemresistant A. baumannii. The isolate was resistant to all-lactams and to several other antibiotics. MICs of imipenem and meropenem were 12 and 6 μg/ mL, respectively. This isolate was positive for the MHT and for MBL production and only blaNDM-1 and blaOXA-58 genes were identified. Conjugation experiments and electro-transformation were unsuccessful. This report shows that Tunisia constitutes a reservoir of NDM-1-producing bacteria. Highly stringent control measures should be applied to prevent this resistance gene spreading into other bacterial species.