e19027 Background: Clostridiodes difficile infection (CDI) is reported to occur up to 9-fold higher in allogenic hematopoietic stem cell transplant (HSCT) recipients compared to the general population of hospitalized patients. This is attributed to disruption of gut microbiome by antibiotics, myeloablative regimens, neutropenia, prolonged hospitalization, and immunosuppressive regimens administered to prevent acute graft-versus-host disease (aGVHD). CDI by disruption of the intestinal microbiome may trigger gastrointestinal aGVHD. Previous studies from HSCT centers have reported conflicting data on the relationship between CDI and subsequent development of aGVHD. Methods: The Nationwide Readmissions Database was queried for admissions of adult allogenic HSCT patients between 2016 and 2018. Those with and without CDI during index admission were compared. Multivariable logistic regression was used to evaluate the primary outcome of risk of aGVHD in the index admission or within 100 days post-engraftment. Results: A total of 13518 allogenic HSCT patients were included in the study. Mean age was 52.4 years. 57.2% of patients were female. The most common underlying diagnoses were acute myeloid leukemia (38%), myelodysplastic syndrome (17%) and acute lymphoblastic leukemia (14%). 11.1% of the index admissions were complicated by CDI. Rates of aGVHD during the index admission or 100 days post-engraftment were similar between CDI and non-CDI groups: 13.8% vs. 12.1%, p=0.19 during index admission and 29.2% vs. 26.1%, p=0.09 during 100 days post-engraftment. Nonetheless, patients with CDI had longer length of hospital stay (34.6 vs 29.8 days, p<0.0001), higher hospitalization costs ($608K vs $506K USD) and greater rate of inpatient mortality (7.3% vs 4.6%, p<0.001). In the multivariate regression analysis, CDI during index admission was not associated with risk of development of aGVHD (Adjusted Odds Ratio 1.14, 95% Confidence Interval 0.87-1.48, p=0.34). Age and unrelated donor HSCT were predictive of risk of aGVHD. Conclusions: CDI during index admission was not predictive of aGVHD during the first 100 days post-allogenic HSCT. HSCT patients are frequency colonized with C.difficile. Diarrhea secondary to CDI may resemble gastrointestinal aGVHD. Therefore, overdiagnosis of CDI in this population is a concern. Antimicrobial stewardship and use of clinical decision support tools have been advocated recently to decrease testing of HSCT patients with C.difficile colonization. Multivariable analysis of risk factors of aGVHD.[Table: see text]
Kumar AJ, Kim S, Hemmer MT, et al. Graft-versus-host disease in recipients of male unrelated donor compared with parous female sibling donor transplants. Blood Adv. 2018;2(9):1022-1031.
