1760. Outcomes of Acyclovir-Resistant Herpes Simplex Virus Infections in Hematologic Malignancies and Hematopoietic Cell Transplant

Background Acyclovir-resistant (ACVr) herpes simplex virus (HSV) infection management is a challenge in patients with hematologic malignancies (HM) and hematopoietic cell transplant (HCT) recipients. Methods Retrospective review of patients aged ≥ 18 years with underlying HM and/or HCT and culture-positive ACVr HSV between 1/1/2009 and December 1/2017 at a tertiary cancer center. Clinical, laboratory, microbiological, and treatment data collected. Results 33 patients identified; 25 (76%) acute leukemias, 3 (9%) chronic myeloid leukemia/chronic lymphocytic leukemia (CML/CLL), 3 (9%) lymphoma, 2 (6%) other HM, and 32 (97%) had HCT. Median age of patients was 59 years (25–73) and 64% of them are females. HCT type: 22 (67%) matched unrelated donor, 3 (9%) cord blood, and 7 (21%) matched related donor. All patients were on acyclovir prophylaxis prior to diagnosis. The median time to onset of ACVr HSV infection was 147 days after transplant. Infection site: 16 (49%) oral, 10 (30%), ano-genital, 5 (15%) oral and esophagus/lung, 2 (6%) esophagus/lung. Pertinent laboratory data on day of viral culture (median/range): white blood cell (WBC) 4.6 cells/µL (0.1–85.9), absolute neutrophil count (ANC) 2,316 cells/µL (0–17,000), absolute lymphocyte count (ALC) 574.5 cells/µL (0–84,182). Serum creatinine at start and end of treatment are 0.8 mg/dL (0.32–1.98) and 0.92 mg/dL (0.36–2.7), respectively. The median duration of treatment was 30 days (4–116). Treatment: 20 (61%) foscarnet, 2 (6%) cidofovir, 4 (12%) foscarnet and cidofovir, 1 (3%) valacyclovir, 5 (15%) high-dose acyclovir, 1 (3%) unknown. 8 (24%) received adjunctive topical therapy: 5 imiquimod, 3 cidofovir. 31 included in outcome analysis (data missing in 2). Infection resolved in 15/31 (48%) while 5/31 (16%) had persistent infection. Median ANC and ALC in those with resolved vs. persistent infection (respectively): 3,082 cells/µL and 642 cells/µL vs. 1,895 cells/µL and 380 cells/µL with a trend toward lower ANC and ALC in patients with persistent infection. Overall mortality was 35% (9/31) while ACVr HSV attributable mortality was 6.4% (2/31). Conclusion ACVr HSV is predominantly encountered in allogeneic HCT, particularly the unrelated donor recipients, and lower ANC/ALC may predispose to persistent infection. Disclosures All authors: No reported disclosures.