Incidence, Risk Factors, And Outcomes Of Patients Who Develop Mucosal Barrier Injury-Laboratory Confirmed Bloodstream Infections In The First 100 Days After Allogeneic Hematopoietic Stem Cell Transplant

Key PointsQuestionWhat outcomes are associated with mucosal barrier injury-laboratory confirmed bloodstream infections in patients who undergo allogeneic hematopoietic stem cell transplant? FindingsIn a case-cohort study of 16875 pediatric and adult patients who underwent allogeneic hematopoietic stem cell transplant between 2009 and 2016, the cumulative incidence of mucosal barrier injury-laboratory confirmed bloodstream infections was 13% by day 100, with infection occurring a median of 8 days after stem cell transplant. Overall survival was significantly decreased among patients who developed a mucosal barrier injury-laboratory confirmed bloodstream infection. MeaningMucosal barrier injury-laboratory confirmed bloodstream infections are associated with significant morbidity and mortality and, by extension, increased use of health care resources.ImportancePatients undergoing hematopoietic stem cell transplant (HSCT) are at risk for bloodstream infection (BSI) secondary to translocation of bacteria through the injured mucosa, termed mucosal barrier injury-laboratory confirmed bloodstream infection (MBI-LCBI), in addition to BSI secondary to indwelling catheters and infection at other sites (BSI-other). ObjectiveTo determine the incidence, timing, risk factors, and outcomes of patients who develop MBI-LCBI in the first 100 days after HSCT. Design, Setting, and ParticipantsA case-cohort retrospective analysis was performed using data from the Center for International Blood and Marrow Transplant Research database on 16875 consecutive pediatric and adult patients receiving a first allogeneic HSCT from January 1, 2009, to December 31, 2016. Patients were classified into 4 categories: MBI-LCBI (1481 [8.8%]), MBI-LCBI and BSI-other (698 [4.1%]), BSI-other only (2928 [17.4%]), and controls with no BSI (11768 [69.7%]). Statistical analysis was performed from April 5 to July 17, 2018. Main Outcomes and MeasuresDemographic characteristics and outcomes, including overall survival, chronic graft-vs-host disease, and transplant-related mortality (only for patients with malignant disease), were compared among groups. ResultsOf the 16875 patients in the study (9737 [57.7%] male; median [range] age, 47 [0.04-82] years) 13686 (81.1%) underwent HSCT for a malignant neoplasm, and 3189 (18.9%) underwent HSCT for a nonmalignant condition. The cumulative incidence of MBI-LCBI was 13% (99% CI, 12%-13%) by day 100, and the cumulative incidence of BSI-other was 21% (99% CI, 21%-22%) by day 100. Median (range) time from transplant to first MBI-LCBI was 8 (<1 to 98) days vs 29 (<1 to 100) days for BSI-other. Multivariable analysis revealed an increased risk of MBI-LCBI with poor Karnofsky/Lansky performance status (hazard ratio [HR], 1.21 [99% CI, 1.04-1.41]), cord blood grafts (HR, 2.89 [99% CI, 1.97-4.24]), myeloablative conditioning (HR, 1.46 [99% CI, 1.19-1.78]), and posttransplant cyclophosphamide graft-vs-host disease prophylaxis (HR, 1.85 [99% CI, 1.38-2.48]). One-year mortality was significantly higher for patients with MBI-LCBI (HR, 1.81 [99% CI, 1.56-2.12]), BSI-other (HR, 1.81 [99% CI, 1.60-2.06]), and MBI-LCBI plus BSI-other (HR, 2.65 [99% CI, 2.17-3.24]) compared with controls. Infection was more commonly reported as a cause of death for patients with MBI-LCBI (139 of 740 [18.8%]), BSI (251 of 1537 [16.3%]), and MBI-LCBI plus BSI (94 of 435 [21.6%]) than for controls (566 of 4740 [11.9%]). Conclusions and RelevanceIn this cohort study, MBI-LCBI, in addition to any BSIs, were associated with significant morbidity and mortality after HSCT. Further investigation into risk reduction should be a clinical and scientific priority in this patient population.This cohort study examines the incidence, timing, risk factors, and outcomes of patients who develop mucosal barrier injury-laboratory confirmed bloodstream infection (MBI-LCBI) in the first 100 days after hematopoietic stem cell transplant (HSCT).