Prognostic Risk Factors of Carbapenem-Resistant Gram-Negative Bacteria Bloodstream Infection in Immunosuppressed Patients: A 7-Year Retrospective Cohort Study

Yulian Gao,1,&ast; Hongxia Lin,1,&ast; Yumin Xu,2,&ast; Yijin Yao,1,&ast; Dake Shi,1 Junjie Li,1 Haixing Zhu,1 Hanssa Dwarka Summah,3 Lei Ni,1 Yun Feng1 1Department of Respiratory and Critical Care Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 2Department of Hospital Infection Management, Department of Infectious Diseases, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 3Department of Respiratory, Poudre D’Or Chest Hospital, Rivière du Rempart, Mauritius&ast;These authors contributed equally to this workCorrespondence: Yun Feng; Lei Ni, Email fy01057@163.com; nilei625@139.comPurpose: Carbapenem-resistant Gram-negative bacteria bloodstream infection (CRGNB-BSI) has gradually become a major threat worldwide due to its treatment difficulty and high mortality. This study aimed to determine the risk factors for CRGNB-BSI in immunosuppressed patients.Patients and Methods: A total of 427 immunosuppressed patients with CRGNB-BSI were retrospectively investigated from 2015 to 2021. Both univariate and multivariate logistic regression analyses were applied to evaluate independent risk factors for CRGNB-BSI.Results: The most common etiology was Klebsiella Pneumoniae (50.59%; 216/427), while the Acinetobacillus baumannii infection was associated with the highest mortality (58.25%) among all etiologies. The 60-day mortality of immunosuppressed patients with CRGNB-BSI was 52.48% (224/427). Procalcitonin (PCT) > 0.5 μg/L (OR = 2.32, 95% CI: 1.28– 4.19, P = 0.005) and age > 55 years (OR = 2.06, 95% CI: 1.17– 3.64, P = 0.012) were found to be predictors of 60-day mortality of CRGNB-BSI, and tigecycline regimen (OR = 3.20, 95% CI: 1.81– 5.67, P < 0.001) was associated with higher mortality. Multivariate analysis also revealed that patients who developed acute kidney injury (AKI) (OR = 2.19, 95% CI: 1.11– 4.30, P = 0.023), gastrointestinal bleeding (OR = 3.18, 95% CI: 1.10– 9.16, P = 0.032), multiple organ dysfunction syndrome (MODS) (OR = 12.11, 95% CI: 2.61– 56.19, P = 0.001), and septic shock (OR = 3.24, 95% CI: 1.77– 5.94, P < 0.001) showed worse outcomes. The risk factors were also significantly associated with mortality in the different subgroups.Conclusion: This study demonstrated that PCT > 0.5 μg/L, age > 55 years, and the tigecycline regimen were significantly associated with higher 60-day mortality among immunosuppressed patients with CRGNB- BSI. Patients developing MODS, septic shock, or AKI had worse clinical outcomes.&#x2003Keywords: bloodstream infection, carbapenem-resistant, immunosuppressed patients, subgroups, prognosis