e18503 Background: Clostridium difficile infection (CDI) is the most important cause of nosocomial infectious diarrhea. Studies suggest patients (pts) undergoing acute myeloid leukemia (AML) chemotherapy (ctx) are at high risk of contracting CDI, but clinical and disease characteristics are not described. This study reports CDI rates and disease characteristics in AML pts at University of Virginia (UVA). Methods: A retrospective review of consecutive pt-encounters undergoing AML ctx at UVA from 2011-2016 was conducted. The main endpoint was to determine the rate of CDI within 90 days of ctx initiation, while assessing pt characteristics, comorbidities, risk factors, and disease specific indices associated with CDI. Statistical methods include nonparametric Wilcoxon and Fisher’s exact tests, with significance defined as p-value < 0.05. Results: Of 142 pts, 44 (31%) AML pts had CDI. 7 pts (15.9%) had 1 recurrent CDI episode,;2 pts (4.5%) had more than one. 18 pts (40.9%) underwent CT imaging specifically for CDI, revealing 3 pts (6.8%) with typhilitis and 2 pts (4.5%) with toxic megacolon requiring colectomy. There was no CDI associated mortality. At CDI diagnosis, 33 pts (75%) were neutropenic and 14 pts (31.8%) received prophylactic antibiotics. Median time from ctx was 12 days. Treatment for CDI: 38 pts (86.4%) single agent metronidazole or vancomycin and 6 pts (13.6%) combination. Sixteen (36.3%) CDI pts achieved CR, while 18 (40.9%) pts relapsed from AML. Compared to non-CDI pts, CDI pts were younger (50 v 59), less obese (BMI 26 v 29), poor-risk cytogenetics (26.5% v 14.1%), CKD (6.8% v 0.7%), prior cancer (6.8% v 2.8%). No statistical difference was seen in demographics (gender, race), comorbidities (tobacco use, pulmonary and cardiac disorders), or AML characteristics (bone marrow cellularity and blast, length of stay). Conclusions: The study concludes that the incidence of CDI in AML pts undergoing ctx is greater than hospitalized patients with or without malignancy as reported in the literature. CDI incidence is increased in younger, less obese, history of CKD or cancer, and poor-risk cytogenetics, suggesting potential predictive risk factors for CDI in AML pts. Further prospective studies are needed to confirm these potential CDI risk factors.
Clostridium difficile Infection Complicated by Transformation of Myelodysplastic Syndrome to Acute Myeloid Leukemia With Leukostasis and Sweet’s Syndrome