EHRLICHIOSIS: A RARE CAUSE OF SEPSIS AND HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS

Abstract

SESSION TITLE: Case Report Semifinalists 1 SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/21/2019 02:30 PM - 03:15 PM INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a rare disorder of uncontrolled immune activation that can lead to multisystem organ failure. HLH is categorized as primary (familial) or secondary with triggers that include infections, malignancy, rheumatologic or metabolic conditions (1). Due to the high morbidity and mortality associated with HLH, early recognition and treatment are paramount. We describe a case of ehrlichiosis induced HLH and sepsis that did not respond to initial broad-spectrum antibiotics. CASE PRESENTATION: A 48 year old female with no significant past medical history presented to an outside hospital for persistent fevers up to 105°F and encephalopathy. Three weeks prior, she reported hiking in Kentucky and had noted multiple 1-2 mm erythematous papules that developed on her lower extremities. Ten days after she returned home, she developed fever, myalgias and malaise which prompted her to seek medical attention. Upon initial presentation, the patient appeared quite ill and the patient was started on broad spectrum antibiotics without improvement. Labs were notable for pancytopenia and a transaminitis. The patient was transferred to our facility on the fourth day of her hospital course. Upon arrival, doxycycline was initiated due to concerns for a tick-borne zoonosis and the patient rapidly improved within 48 hours of treatment. Given the constellation of symptoms evaluation for HLH was initiated and confirmed with a bone marrow biopsy significant for hemophagocytic histiocytes. The patient was continued on doxycycline and dexamethasone was initiated. An Erlichia chaffeensis PCR was obtained during the evaluation and was positive. The patient’s remaining infectious work-up was unremarkable with the exception of a positive qualitative EBV PCR. While EBV has been well described in its association to HLH, the robust improvement in the patient’s condition after initiation of doxycycline lends merit to ehrlichiosis as a cause for the patient’s HLH. The patient improved and was discharged home to complete a 14-day course of doxycycline. DISCUSSION: Ehrlichiosis is a rare cause of hemophagocytic lymphohistiocytosis with less than 15 adult cases reported in the literature (2-3). This is likely an underrecognized cause of HLH and the finding of HLH should prompt physicians to take a thorough travel and social history. As seen in our case, sepsis due to Ehrlichiosis does not respond to conventional antibiotics and thus initiation of doxycycline should be part of the antibiotic regimen if a tick-borne illness is suspected. CONCLUSIONS: Ehrlichiosis is an underrecognized cause of hemophagocytic lymphohistiocytosis. Reference #1: Schram AM, Berliner N. How I treat hemophagocytic lymphohistiocytosis in the adult patient. Blood 2015;125(19):2908-14. Reference #2: Naqash AR, Yogarajah M, Vallangeon BD, Hafiz M, Patel D, Kolychev E, Lebron DA, Liles D. Hemophagocytic lymphohistiocytosis (HLH) secondary to ehrlichia chaffeensis with bone marrow involvement. Ann Hematol. 2017;96(10):1755-1758. Reference #3: Wilfong EM, Hewlett JC, Kerchberger VE, Bloch KC, Sevin CM. Ehrlichia – an unusual cause of hemophagocytic lymphohistiocytosis. Am J Respir Crit Care Med 2018;197:A3386. DISCLOSURES: No relevant relationships by Erum Arain, source=Web Response No relevant relationships by Paul Chung, source=Web Response No relevant relationships by Emily Gilbert, source=Web Response