Clinical Impact of Biofilm-Producing Carbapenem-Resistant Acinetobacter baumannii: Diagnosis and Treatment Challenges

Carbapenem-resistant Acinetobacter baumannii (CRAB) has emerged as a major nosocomial pathogen associated with significant morbidity and mortality, particularly in intensive care unit (ICU) settings. Its remarkable ability to survive in adverse environments, persist on medical devices, and rapidly acquire multidrug resistance has made it a critical global healthcare concern. This review aims to provide a comprehensive overview of the epidemiology, risk factors, antimicrobial resistance mechanisms, and pathogenicity of CRAB, with a special emphasis on the role of biofilm formation. CRAB infections are strongly associated with prolonged hospitalization, mechanical ventilation, previous antibiotic exposure, and invasive procedures. The organism exhibits multiple resistance mechanisms, including carbapenemase production, efflux pumps, porin modifications, and horizontal gene transfer, which significantly limit therapeutic options. A key virulence factor is its capacity to form biofilms on biotic and abiotic surfaces, enhancing bacterial survival, immune evasion, and resistance to antimicrobial agents. Biofilm-associated infections are often chronic, recurrent, and difficult to eradicate, particularly in device-related infections. The interplay between biofilm formation and antimicrobial resistance further complicates treatment outcomes. Current management strategies rely on last-resort antibiotics, combination therapy, antimicrobial stewardship, and strict infection control practices, while emerging therapies targeting biofilms offer promising alternatives. Understanding these complex mechanisms is essential for developing effective therapeutic and preventive strategies against CRAB infections.