Comparative Effectiveness of Cidofovir Preemptive Therapy for Human Adenovirus Infection in Pediatric Hematopoietic Cell Transplant Recipients

Background. Infection is a serious complication of left ventricular assist device (LVAD) therapy. However, an optimal antimicrobial surgical infection prophylaxis (SIP) regimen for LVAD implantation is not well established. We compared risk of LVAD specific infections and all-cause mortality outcomes between SIP regimens at postoperative day 90 and one year using Kaplan-Meier time to event analysis. Methods. We retrospectively reviewed 239 adults who underwent continu-ous-flow LVAD implantation from February 2007 to March 2015 at Mayo Clinic Rochester. LVAD infection (LVADI) was defined using criteria published by the International Society for Heart and Lung Transplant. Patients excluded from the ana- lysis included those who did not have HeartMate II or HeartWare device, patients with incomplete documentation of SIP, and those with an actively treated infection at the time of LVAD implantation. Background. Older studies in hematopoetic stem cell transplantation recipients (HSCT), who receive parental nutrition (TPN) suggest a trend for increased risk of infection. An retrospective study was done to compare incidence, spectrum of infec- tion, risk factors and clinical outcomes for patients who received TPN compared with those not treated with TPN during HSCT. methods. All HSCT recipients treated between 2005 and 2012 were included. All documented bacterial and fungal infections are included. Patients received at least 48 hour TPN. Results. In total, 1,367 patients underwent HSCT including 197 who received TPN. There was no difference between groups for age ( P < 12:30 PM Background. Patients undergoing hematopoietic stem cell transplant (HSCT) are at high risk of developing Clostridium difficile infection (CDI), in part due to routine exposure to broad-spectrum antimicrobial therapy for prevention of infection. Limited data suggest oral vancomycin (VAN) may be effective in preventing recurrent CDI (rCDI) among patients with a history of CDI receiving systemic antimicrobial ther- apy. However, there is no published literature supporting this strategy to prevent rCDI among patients undergoing HSCT. Methods. We conducted a single-center matched cohort study of adult (≥18 years) patients with a history of CDI who underwent HSCT between 1/2012 and 3/2017. Patients who received oral VAN prophylaxis (VAN) were matched 1:2 based on age (± 5 years) and transplant type (allogeneic vs. autologous) to patients who did not receive VAN prophylaxis (no-VAN). Treatment groups were characterized using descriptive statistics and differences compared using conditional logistic regression. A marginal structural Cox model was constructed using robust sandwich variance estimation to evaluate the risk of rCDI between groups after adjusting for concurrent systemic antibiotic exposure. Results. A total of 65 patients were eligible for inclusion; 9 VAN patients were matched to 18 no-VAN patients for a final cohort size of 27. Mean age was not significantly different between VAN and no-VAN patients (60.9 vs. 60.7 years, P = NS). There were no significant baseline differences between groups. The most common VAN dose for prophylaxis was 125 mg QID (88.9%). There was no difference between groups in either rCDI (11.1% VAN vs. 5.6% no-VAN, P = NS) or mortality (11.1% VAN vs. 16.7% no-VAN, P = NS) within 100 days of HSCT. The adjusted hazard ratio for rCDI was 0.97 (95% confidence interval: 0.25 to 3.37). are needed to draw more definitive conclusions about oral VAN prophylaxis in patients undergoing HSCT, and further study is needed to identify optimal strategies to prevent rCDI in this high-risk population. Background. Human adenovirus (HAdV) has been associated with significant morbidity and mortality in pediatric hematopoietic cell transplant (HCT) populations. This has led some centers to adopt a preemptive approach of plasma surveillance test- ing with initiation of cidofovir at detection of asymptomatic HAdV. While cidofovir has been shown to have in vitro activity against HAdV there are no comparative effect- iveness data for preemptive therapy. Methods. Allogeneic HCT recipients between 2004 and 2013 with asymptom- atic HAdV infection detected during plasma surveillance testing within 160 days from transplant were retrospectively identified at Children’s Hospital of Philadelphia. A dis- crete-time model was performed to assess the effectiveness of preemptive cidofovir in preventing the progression of HAdV infection. of HAdV was defined a one-log increase in the plasma HAdV viral load or development of HAdV disease within 2 to 21 days of first detection of HAdV in the plasma. HAdV disease was defined by organ-specific radiologic and laboratory data. Inverse proba-bility treatment weights (IPTW) were included in the model to adjust for a patient’s likelihood to receive preemptive cidofovir. Background. No study has recently characterized the real-world incidence of cytomegalovirus (CMV) infection and patterns of CMV antiviral treatment strategies with a focus on toxicities associated with these antivirals in allogeneic HCT recipients in the USA. The purpose of this study was to describe the rates of CMV infection and antiviral treatment patterns from multiple transplant centers in the USA. Methods. This was a three-center, retrospective observational study of allogenic HCT patients from 2006 to 2013. For each patient, data relevant to CMV infection and treatment outcomes were collected with a specific focus on toxicities associated with CMV antivirals (nephrotoxicity, myelosuppression, and electrolyte abnormality). Results. Three hundred and seventeen patients with a total follow-up time of 244,714 patient-days were included. The most common malignancies requiring HCT were acute leukemia (60.9%), lymphoma (17.7%), and myelodysplastic syndrome (11.4%). CMV infection occurred in 37.5% of patients. Among patients receiving preemptive therapy for cytomegalovirus, valganciclovir was the most commonly used antiviral (76.5%) followed by foscarnet (19.1%), ganciclovir (15.7%), and cidofovir (2.6%). Anemia was the most common toxicity which occurred in 70.4% of patients, followed by thrombocytopenia (45.2%), neutropenia (44.3%), and AKI (29.6%). No relationship was observed between choice of antiviral and the development of neutropenia or nephrotoxicity. Conclusion. A high rate of toxicities associated with anti-CMV antivirals was identified in a large cohort of allogenic HCT patients. Disclosures. All authors: No reported disclosures.