Antibiotic Resistance Patterns of Enterobacteriaceae Isolated from Tobruk Medical Centre

Abstract

Antimicrobial resistance poses a major threat to human health around the world. Resistance of the Enterobacteriaceae to antibiotics, especially of the β-lactam type, is increasingly dominated by the mobilization of continuously expressed single genes that encode efficient drug-modifying enzymes. This study from Tobruk Medical Centre characterized resistance patterns in Enterobacteriaceae across different antimicrobial classes. Enterobacteriaceae from hospital samples were isolated on blood and MacConkey agar. Stool samples were cultured on S.S. agar, Sorbitol MacConkey agar, and Mueller-Hinton broth for swab inoculation. To determine antimicrobial susceptibility patterns, the multidrug resistance disc diffusion method was used. The findings revealed that Escherichia coli was the most prevalent bacterial isolate, followed by Klebsiella spp., while lower prevalence rates were observed for other organisms, such as Proteus and Enterobacter. This study demonstrated a markedly high resistance rate to cephalosporins, which showed the highest percentages among both inpatient and outpatient isolates, with significantly greater resistance observed in inpatient settings. Carbapenems exhibited moderate resistance levels compared with other antimicrobial classes, whereas aminoglycosides showed substantially increased resistance among inpatient isolates. Quinolones also demonstrated relatively high resistance rates in both patient groups. Analysis based on specimen type indicated that blood and abscess samples exhibited the highest antimicrobial resistance rates, particularly against cephalosporins, while carbapenems and aminoglycosides displayed comparatively lower resistance in certain specimen categories. Furthermore, Klebsiella spp. isolates demonstrated elevated resistance to ceftriaxone and ampicillin compared with other bacterial isolates. These findings highlight the growing prevalence of antimicrobial-resistant bacterial strains, especially in hospital environments, emphasizing the urgent need for strengthened infection prevention and control strategies, implementation of antimicrobial stewardship programs, and continuous surveillance of resistance patterns to improve treatment outcomes and limit the future spread of resistant pathogens.