Prognostic Factors and Outcomes in Patients With Septic Shock After Allogeneic Hematopoietic Stem Cell Transplantation

Abstract

Septic shock remains a potentially life-threatening complication among allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. There is a paucity of information on the clinical characteristics, outcome and prognostic factors of septic shock patients after allo-HSCT. We aimed to describe the clinical characteristics of septic shock after allo-HSCT and its associated health outcomes and to evaluate the role of patient demographics, transplantation-related laboratory and clinical variables associated with the short-term mortality of septic shock after allo-HSCT. We retrospectively studied 242 septic shock patients from 6105 consecutive patients allografted between 2007 and 2021. We assessed 29 risk factors as candidate predictors and used multivariable logistic regression to establish clinical model. The primary outcome was 28-day mortality. The median age of the subjects was 34 (IQR 24 to 45) years. A total of 148 patients (61.2%) had positive blood cultures. Gram-negative bacilli accounted for 61.5% of the positive isolates, gram-positive cocci accounted for 12.2%, and fungi accounted for 6.1%. Coinfections were found in 30 (20.3%) patients. Escherichia coli was the dominant isolated pathogen (31.1%), followed by Pseudomonas spp. (12.8%) and Klebsiella pneumoniae (10.1%). With a median follow-up of 34 (IQR: 2 to 528) days, a total of 142 (58.7%) patients died, of whom 118 (48.8%) died within the first 28 days after septic shock diagnosis, 131 (54.1%) died within 90 days, and 141 (58.3%) died within 1 year. A large majority of deaths (83.1% [118/142]) occurred within 28 days of septic shock diagnosis. Finally, 6 independent predictive variables of 28-day mortality were identified by multivariable logistic regression: time of septic shock, albumin, bilirubin, PaO₂/FiO₂, lactate, and sepsis-induced coagulopathy. Patients with late onset shock had higher 28-day mortality rates (64.6% versus 25.5%, P < .001) and more ICU admission (32.6% versus 7.1%, P < .001) than those with early onset shock. We highlight the poor survival outcomes in patients who develop septic shock, emphasizing the need for increasing awareness regarding septic shock after allo-HSCT. The information from the current study may help to assist clinicians in identifying high-risk patients.

Keywords: Allogeneic hematopoietic stem cell transplant; Outcome; Septic shock.