662. Tick Borne-Associated Thrombocytopenia Among United States Veterans in Long Island New York

BACKGROUND: Long Island, New York, is highly endemic for tick borne illnesses (TBI) with rising numbers of cases in the past years. Thrombocytopenia is a known complication of babesiosis caused by Babesia microti, anaplasmosis caused by Anaplasma phagocytophilum, and ehrlichiosis caused by Ehrlichia chaffeensis. We identified cases of thrombocytopenia attributed to TBI in our institution. METHODS: Retrospective chart review of patients diagnosed with babesiosis, anaplasmosis, and ehrlichiosis from 2000 to 2017 at Northport Veterans Affairs Medical Center. Demographics, method of diagnosis (PCR/serologies), CBC/chemistries, treatment choices, and outcomes were analyzed. RESULTS: Thirty-two veterans (VETS) were identified with the following TBI: Babesiosis 22, Ehrlichiosis 6, Anaplasmosis 4. The majority of cases (19) were from Suffolk County, Long Island. The median (MED) age of this group was 62 years (range 31–89). Ninety-one percent were Caucasian, 9% Black. 37.5% had history of tick bite. The MED temperature on presentation was 101.9°F (range 97.6–105.2°F). 56% had HTN, 6% DM, 37% HLD, 9% hepatitis C, 3% HIV. Laboratory studies: MED platelet count 88,000/µL (36,000–161,000); MED hemoglobin 12 gm/dL (5.6–15.6); MED ALT 41 IU/L (6–330); MED LDH 335 IU/L (193–1,322). Twelve VETS had positive C6 peptide. The peak MED B. microti parasitemia was 1.4% (0.1–3%). PCR tests were available in the later years of the study period: three were positive for E. chaffeensis, two for A. phagocytophilum, and 14 for B. microti. The majority of the cases (19) were observed after year 2010. Morulae were seen in only one case. Haptoglobin in eight VETS was undetectable. One veteran with history of splenectomy and babesiosis with 3% parasitemia required exchange transfusion with 12 units of PRBCs. Two other babesiosis cases required regular transfusion of PRBCs. 20 babesiosis cases were treated with azithromycin-atovaquone and two with clindamycin-primaquine. Doxycycline was used in the other cases. One patient developed NSTEMI and required coronary stent placement. Platelet counts returned to baseline levels with treatment. No deaths occurred. CONCLUSION: The incidence of TBI in Long Island, New York is rising. PCR testing for TBI can be utilized in our VETS presenting with febrile illness and thrombocytopenia to help identify the possible tick borne pathogen during the months of high tick activity. DISCLOSURES: All authors: No reported disclosures.