Treatment strategies and mortality risk factors in patients with multidrug-resistant Acinetobacter baumannii pneumonia: A retrospective analysis.

Estrategias de tratamiento y factores de riesgo de mortalidad en pacientes con neumonía por Acinetobacter baumannii multirresistente: Un análisis retrospectivo.

• Lili Liu Infection Control Department, The Third People’s Hospital of Yichang City, No. 23, Gangyao Road, Xiling District, Yichang City, Hubei Province, China. https://orcid.org/0009-0005-0283-3094
• Wen Lu Department of Critical Care Medicine, The Third People’s Hospital of Yichang City, No. 23, Gangyao Road, Xiling District, Yichang City, Hubei Province, China. https://orcid.org/0009-0000-1845-3962
• Gege Fang Department of Pulmonary Medicine III, The Third People’s Hospital of Yichang City, No. 23, Gangyao Road, Xiling District, Yichang City, Hubei Province, China. https://orcid.org/0009-0004-5947-6131
• Wei Zhang Department of Critical Care Medicine, The Third People’s Hospital of Yichang City, No. 23, Gangyao Road, Xiling District, Yichang City, Hubei Province, China. https://orcid.org/0009-0003-4892-0973

DOI: https://doi.org/10.54817/IC.v67n1a08

Keywords: Acinetobacter baumannii, Pneumonia, Drug Resistance, Multiple, Risk Factors, Tigecycline

Abstract

This study aimed to investigate the determinants of drug resis- tance risk factors, 30-day all-cause mortality risk factors, and related clinical treatment strategies in patients with multidrug-resistant Acinetobacter bauman- nii (MDRAB) pneumonia. This retrospective study analyzed data from 168 pa- tients with MDRAB pneumonia and 141 patients with non-MDRAB pneumonia between February 2022 and February 2025. On the second day of admission, the severity of illness and use of carbapenems, tigecycline, etc., were higher in MDR- AB pneumonia patients than in non-MDRAB pneumonia patients (p<0.05). The risk factors significantly associated with MDRAB pneumonia included ICU stay prior to AB infection (p<0.001), APACHE II score ≥ 18 (p=0.002), invasive pro- cedures (p<0.001), septic shock (p=0.002), and drug abuse (p<0.001). Length of ICU stay before culture, recent surgery, APACHE II score ≥18, tigecycline- containing treatment, and the use of two or more antibiotic types (all p<0.05) were significantly linked to 30-day mortality. In a cohort of 168 MDRAB patients, the non-tigecycline treatment group (n=85) showed a significantly lower 30-day mortality rate compared to the tigecycline treatment group (n=83) (p=0.003). Among those receiving tigecycline, the incidence of gastrointestinal adverse re- actions was significantly higher, while allergic reactions were less frequent (both p<0.05). In conclusion, prior ICU admission, invasive procedures, and drug abuse are risk factors for developing MDRAB. Severe pneumonia and tigecycline treatment are strongly associated with higher mortality in MDRAB patients, and tigecycline should be used cautiously.

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