Katie Capp
Univ of Minnesota, Div of Pulmonary, Allergy, Critical Care & Sleep Medicine
Minneapolis, Minnesota
Disclosure information not submitted.
Ham Kealy, MD
Critical Care Medicine Physician
Regions Hospital
Saint Paul, Minnesota, United States
Disclosure information not submitted.
Title: A COVID Positive Patient with ARDS secondary to Anaplasmosis
Case Report Body:
Introduction: Anaplasma phagocytophilum is a tick-borne obligate intracellular bacterium that belongs to the genus Ehrlichia and is the causative agent of human granulocytic anaplasmosis (HGA). A. pharocytophilum is transmitted via the Ixodes tick most commonly in spring and summer. The classic presentation of HGA includes fevers, nonspecific symptoms, leukopenia, anemia, thrombocytopenia and transaminitis. Symptoms begin 5-14 d after exposure to tick bite. Diagnosis is based on clinical suspicion and confirmatory lab testing. Empiric treatment should not be delayed. Diagnostic testing includes serologies, peripheral smear with morulae and PCR.1,2
Description: 33y healthy woman presented during the Minnesota summer with abdominal pain and SOB 1 month after an asymptomatic positive COVID-19 test. She was febrile at 102.4°F, tachycardic, tachypneic and hypoxemic (SpO2 70% on RA). Work up revealed mild transaminitis, leukopenia, and thrombocytopenia. A CT showed LUL and RLL opacities. She was treated for sepsis with fluids and broad-spectrum antibiotics. She worked on a farm and rode horses as a hobby so doxycycline was initiated. A peripheral blood smear was sent, revealing morulae. COVID-19 PCR was again positive. She rapidly developed shock and ARDS requiring intubation and pressors. Infiltrates and hypoxemia worsened. Cultures remained negative. The RT-PCR cycling threshold for her COVID was >35. She was more than 30d from her initial positive, making it unlikely that her illness was due to COVID.3 She extubated on day 4 of ARDS protocol.
Discussion: This is a rare clinical presentation of HGA with ARDS. Prior case reports of ARDS due to HGA noted improvement with steroids in addition to doxycycline.4,5,6 This patient improved on monotherapy of doxycycline. Early initiation of therapy improves outcomes in HGA infections7. There is evidence that some of the mechanism of injury leading to ARDS in patients with HGA is similar to COVID with macrophage activation and excessive cytokine production.8 A thorough social history and avoiding anchoring heuristics can guide diagnosis. Early recognition and treatment with doxycycline can reduce overall morbidity and mortality.