665. Key Clinical and Laboratory Features in Early Diagnosis of Ehrlichiosis in an Endemic Area of Long Island, New York

BACKGROUND: Human monocytic ehrlichiosis (HME) is a tick-borne disease caused by Ehrlichia chafeensis in the northeast United States. Suffolk County, New York has the highest amount of HME cases in NY (176 from 2010 to 2014). Our aim is to identify risk factors for HME and compare clinical presentation and laboratory findings of young vs. older adults. METHODS: A retrospective chart review from January 1, 2014 to December 31, 2017 was performed on all patients ≥18 years who presented to the ER at Stony Brook University Hospital (SBUH) or Stony Brook Southampton Hospital (SBSH) with (i) ICD-9 code 082.4 or ICD-10 code A77.40 and (ii) a positive E. Chafeensis PCR. Data were collected on demographics, clinical presentation, and laboratory results. RESULTS: Twenty-seven cases of HME were found and separated into Group 1 (G1, n = 10) or Group 2 (G2, n = 17) based on age (Table 1). G1 had a significantly higher chance of being Hispanic than G2. Twenty-four of the 27 patients (89%) were hospitalized with an average length of stay of 3.4 days (range 1–14 days).The only significant difference in clinical presentation was that G1 was more likely to have myalgia (P = 0.02). 40% or more of patients in both groups presented with an acute kidney injury and the average length of hospital stay in days was 4.0 ± 2.9 and 3.2 ± 3.1 for G1 and G2, respectively. The number of cases overall have increased 6.0% per year between 2014 and 2017. Thrombocytopenia presented in all cases. Conclusion. HME is prevalent in Suffolk County. Clinical presentation and laboratory findings were largely similar between the two groups, except the younger population more often presented with myalgia. A risk factor in this study was to be young and Hispanic, likely due to occupational exposure. DISCLOSURES: All authors: No reported disclosures.