Acinetobacter baumannii Infection-Related Mortality in Hospitalized Patients: Risk Factors and Potential Targets for Clinical and Antimicrobial Stewardship Interventions

Abstract

Due to resistance and scarcity of treatment options, nosocomial Acinetobacter baumannii infections are associated with significant fatality rates. We investigated the factors contributing to infection-related deaths to develop tailored stewardship interventions that could reduce these high mortality rates. We reviewed the medical records of adult inpatients with A. baumannii infections over two years. Patient demographics and clinical data were collected and statistically analyzed. The study included 321 patients with positive A. baumannii microbiological cultures, with respiratory infections accounting for 58.6%, soft tissues 29.3%, bacteremia 8.6%, urine 2.1%, and others 1.4%. The study population’s median (IQR) age was 62.6 (38.9–94.9) years, and hospital stay was 20 (9.5–40) days. Statistical analysis revealed that various risk factors contribute significantly to high in-hospital all-cause mortality (44%), as well as 14-day and 28-day mortality rates. Deaths increased by a factor of 1.04 with every additional year of age (p = 0.000), admission to the critical care unit (p = 0.000, OR: 2.86), and patients admitted with an infectious diagnosis had nearly three times the mortality rate as those admitted with other diagnoses (p = 0.000, OR: 3.12). Male gender (p < 0.001, OR: 2.14), any comorbid conditions (p = 0.000, OR: 5.29), prolonged hospitalization (>7 days) (p = 0.023, OR: 1.98), and hospital acquisition of infection (p = 0.027, OR: 1.68) were among the most significant predictors of mortality. All variables were investigated for their impact on all-cause, 14-day, and 28-day mortality rates. Improving multidisciplinary infection control practices, regular disinfection of patient care equipment, and optimal intubation practice that avoids unnecessary intubation are necessary interventions to reduce infection-related mortality rates. Better antibiotic selection and de-escalation, shorter hospital stays whenever possible, prompt medical stabilization of comorbid conditions, and fewer unnecessary admissions to critical care units will all lead to improved outcomes.

Cefiderocol-Based versus Colistin-Based Regimens for Severe Carbapenem-Resistant Acinetobacter baumannii Infections: A Propensity Score-Weighted, Retrospective Cohort Study during the First Two Years of the COVID-19 Pandemic

“…The two-treatment group (cefiderocol versus colistin) significantly differed for the following characteristics: age (patients treated with colistin were significantly older); the prevalence of diabetes and obesity (which were more frequent in the group treated with colistin); length of stay (significantly longer in the group receiving cefiderocol-based regimen); and the type of infection (BSIs were more frequent in the group receiving cefiderocol, while pneumonia was more frequent in the group receiving colistin-based treatment). The median duration of antibiotic treatment was 13 days (11)(12)(13)(14)(15)(16). Overall, the mortality rate was 43% (48/111), with a higher proportion of death (even if not statistically significant) in patients treated with cefiderocol versus those receiving colistin-based regimens (26/60 (51%) versus 22/51 (37%), p = 0.130).…”

“…On the one hand, this is often related to the severity of the underlying diseases that characterized hospitalized patients, but on the other hand, it should be mentioned that the therapeutic options available for the treatment of CR-Ab infections are very limited, thus increasing the risk of inappropriate empirical therapy and consequent mortality [13,14]. Some of the most significant predictors of mortality due to CR-Ab infections include prolonged hospitalization, advanced age, male gender, multiple comorbidities, having an infection at the moment of admission, and being admitted to an intensive care unit [15].…”

Occurrence of Multidrug-Resistant Strains of Acinetobacter spp.: An Emerging Threat for Nosocomial-Borne Infection in Najran Region, KSA

“…A. baumannii has become a predominant nosocomial pathogen, particularly in critical care units (ICU) [ 17 , 18 , 19 , 20 ]. Numerous infections, including bacteremia, meningitis, infections of the urinary tract, bloodstream, or surgical wounds, and ventilator-associated pneumonia, have also been reported to be caused by A. baumannii [ 21 , 22 ].…”

Infections in Glucose-6-Phosphate Dehydrogenase G6PD-Deficient Patients; Predictors for Infection-Related Mortalities and Treatment Outcomes

“…This discrepancy may have been a logical effect of the difference in the nature, severity of cases, and underlying comorbid conditions [ 38 , 39 ]. Although a diversity of pathogens, including Acinetobacter baumannii, Klebsiella pneumonia , Coagulase-negative Staphylococcus, and candida species, are commonly involved in polymicrobial infections, the strong association between polymicrobial infections and high mortality rates is maintained over all pathogens [ 40 , 41 , 42 ]. In our cohort, the deteriorating immune status of these patients contributed to the increased exposure to polymicrobial infections as a large proportion of them suffer from chronic diseases (92%), mostly diabetes and heart diseases, in addition to the exposure to invasive procedures (87%) and needed a blood transfusion due to excessive hemolysis triggered by infections (70%).…”