Abstract

Background: The global spread of β-lactamase-producing Gram-negative rods (GNRs) poses a significant threat to the treatment of bacterial infections, as these pathogens are resistant to most β-lactam antibiotics. Aminoglycosides have emerged as an alternative treatment option. This study aimed to detect aminoglycoside acetyltransferase genes AAC (3)-II and AAC (6')-Ib among extended-spectrum β-lactamase (ESBL)-producing GNRs isolated from clinical specimens in Sudan.

Methods: A cross-sectional study was conducted on 143 Gram-negative clinical isolates collected from hospitals in Khartoum State between August and September 2022. The isolates were screened for ESBL production using the double-disc synergy test. DNA was extracted using a modified boiling protocol, and multiplex PCR was performed to detect the AAC (3)-II and AAC (6')-Ib genes.

Results: Among the 143 isolates, 100 were confirmed as ESBL-producing GNRs. The predominant ESBL-producing organisms included Pseudomonas aeruginosa, Acinetobacter spp., Escherichia coli, Proteus spp., Klebsiella spp., and Salmonella spp. The AAC (6')-Ib gene was detected in 23% (23/100) of the isolates, whereas the AAC (3)-II gene was not detected in any isolates (0/100).

Conclusion: A high prevalence of the AAC (6')-Ib gene was observed among ESBL-producing Gram-negative isolates in Sudan, indicating an increased resistance pattern that requires urgent attention to mitigate its clinical and public health impact.