298. Clinical Features of PCR Confirmed Human Ehrlichiosis and Anaplasmosis in an Endemic Area of the Northeast U.S.
Session: Poster Abstract Session: Global Infections
Thursday, October 5, 2017
Room: Poster Hall CD
Background: The clinical manifestations for Ehrlichiosis and Anaplasmosiscan, two tick-borne diseases, can be indistinguishable in endemic areas. The antibody-capture serological tests for these infections have low sensitivity in acute illness and the follow up convalescent titers needed to confirm the diagnosis are rarely checked in clinical practice. Now, blood PCR testing for Ehrlichia and Anaplasma is increasingly more available to aid in accurate diagnosis. The aim of this study was to characterize and compare the clinical features of Ehrlichiosis and Anaplasmosis by using PCR as the gold standard for case definition in an endemic area of the Northeast U.S.

Methods: A retrospective chart review was performed in all patients with ICD-9 or ICD-10 diagnostic codes for Ehrlichiosis or Anaplasmosis between 2014 and 2016 at Southampton Hospital (a major community hospital for the rural east end of Suffolk County, Long Island, NY) and Stony Brook University Hospital (the only tertiary medical center in Suffolk County). Inclusion criteria consisted of a positive blood PCR for either Anaplasma phagocytophilum or Ehrlichia spp. (chaffeensis, canis, muris-like or ewingii). Demographics, clinical and laboratory variables were collected and compared to distinguish characteristics of these two different infections. Cases with 3 or more previously defined markers of severe disease [acute kidney injury (AKI), leukopenia, thrombocytopenia, elevated transaminases] were defined as severe cases.

Results: A total of 15 cases of Ehrlichiosis (E, mean age: 72.1 ±12.6) and 11 cases of Anaplasmosis (A, mean age: 63.8 ±13.5) were compared. Clinical presentation was similar with the two most common symptoms: fever (E 86.7%, A 90.9%) and fatigue (E 80.0%, A 72.7%). Average length of stay for hospitalized patients was 3.07 (E) and 2.91 (A, p=.58) days, respectively. Leukopenia (E 93.3%, A 63.6%; p =0.06), thrombocytopenia (E 100%, A 81.8%; p =0.09), AKI (E 53.3%, A 18.2%; p =0.07) and transaminitis (E 46.7%, A 27.3%; p =0.32) was more common for Ehrlichiosis. Severe cases were observed significantly more with Ehrlichiosis than Anaplasmosis (E 73.3% vs A 27.3%, p = 0.02).

Conclusion: Ehrlichiosis and Anaplasmosis had similar clinical presentations while laboratory data was more severe for Ehrlichiosis in cases from an endemic area in the Northeast of the U.S.

Zachary Fleischner, MD1, Teresa Koo, MD2, Mehtap Haktanir Abdul, MD2 and Luis A. Marcos, MD, MPH2, (1)Internal Medicine, Stony Brook University Hospital, Stony Brook, NY, (2)Infectious Diseases, Stony Brook University Hospital, Stony Brook, NY


Z. Fleischner, None

T. Koo, None

M. Haktanir Abdul, None

L. A. Marcos, None

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