Acinetobacter: An Emerging Threat to Hospitalized Patients

Abstract

Acinetobacter baumannii(A. baumannii) has emerged as one of the most important opportunistic pathogens associated with healthcare-associated infections worldwide. Its remarkable ability to survive in hospital environments, acquire antimicrobial resistance determinants, and cause outbreaks in intensive care units has made it a major public health concern. This review summarizes the taxonomy, epidemiology, virulence mechanisms, antimicrobial resistance patterns, clinical significance, current therapeutic approaches, and future treatment prospects of Acinetobacter 
species, with particular emphasis on multidrug-resistant (MDR) A. baumannii. A comprehensive review of published literature was conducted, focusing on global and regional epidemiology, molecular mechanisms of pathogenicity and resistance, diagnostic methods, and emerging therapeutic strategies against MDR and carbapenem-resistant A. 
baumannii. A. baumannii is a leading cause of ventilator-associated pneumonia, bloodstream infections, urinary tract infections, and wound infections, particularly among critically ill and immunocompromised patients. Its pathogenicity is mediated by multiple virulence factors, including outer membrane proteins, capsular polysaccharides,  lipopolysaccharides, fimbriae, and biofilm formation. The organism demonstrates extraordinary genomic plasticity, enabling the acquisition and dissemination of resistance genes through plasmids, transposons, integrons, and insertion sequences. Consequently, MDR, extensively drug-resistant (XDR), and pan-drug-resistant (PDR) strains have become increasingly prevalent worldwide. Although carbapenems remain effective against susceptible isolates, treatment options for resistant strains are limited. Novel agents such as sulbactam-durlobactam, cefiderocol, abaucin, antimicrobial peptides, and phototherapy represent promising future interventions. MDR A. baumannii continues to pose a significant challenge to modern healthcare systems. Strengthened infection control practices, antimicrobial stewardship programs, continuous surveillance, and the development of innovative therapeutic strategies are essential to mitigate the growing threat of this highly adaptable pathogen.

The Journal of Ad-din Women's Medical College; Vol. 14(1), Jan 2026; p 45-55