Anaplasmosis: A Case Report and Literature Review

1Mount Sinai School of Medicine, New York, NY

Meeting: Hospital Medicine 2011, May 10-13, Dallas, Texas.

Abstract number: 308

Case Presentation:

We describe a 79‐year‐old man with a history of hypertension and benign prostatic hypertrophy who presented with 5 days of fevers to 103°F and myalgias. The patient also complained of a dry cough for 3 days. Further questioning revealed that 2 weeks prior, he had skinned a deer with his bare hands. On presentation he had a temperature to 40°C, was hypoxic, tachycardic, tachypneic, and in mild respiratory distress, and had decrease breath sounds at the left lung base. Laboratory studies were remarkable for a mild leukocytosis, mild anemia, and significant thrombocytopenia, 37 × 103/μL (150–450 × 103/μL). The patient had a mild indirect bili‐rubinemia and elevated AST. CT scan of the chest revealed left pleural effusion and splenomegaly. The patient was placed on oxygen, and empiric treatment for community‐acquired pneumonia was initiated. Among the multiple tests done, a peripheral blood smear were performed, which revealed intracellular parasites in granulocytes. A provisional diagnosis of anaplasmosis was made. The diagnosis was confirmed with a positive buffy coat and serologies that showed elevated A. phagocytophilum IgG [1:512 (<1:64)] and IgM [>1:640 (<1:20)]. The patient was started immediately on doxycycline and within 24 hours had considerably improved respiratory status and resolution of fevers. Within 1 week, creatinine and platelets had normalized.


Human granulocytic anaplasmosis (HGA) is a tick‐borne infection caused by Anaplasma pha‐gocytophilum. More than 2963 cases of HGA have been reported to state and federal agencies since 1994, and this is likely a gross underestimate of the true burden. Like our patient, individuals with HGA present with a nonspecific febrile illness and can range from asymptomatic to a severe, sometimes fatal disease. The differential diagnosis is broad and includes viral infection from herpes viruses or enteroviruses, hematologic conditions including thrombotic thrombocytopenic purpura and idiopathic thrombocytopenic purpura, other vector borne zoonoses, lymphoma, and leukemia. Treatment with appropriate antibiotics is curative.


We present a typical case of anaplasmosis and highlight the importance of considering tick‐borne zoo‐noses in patients with nonspecific fever syndromes and hematologic abnormalities. We also review the most recent literature on human granulocyte anaplasmosis.


S. Kanjilal ‐ none; E. Brutsaert ‐ none; B. Markoff ‐ none

To cite this abstract:

Kanjilal S, Brutsaert E, Markoff B. Anaplasmosis: A Case Report and Literature Review. Abstract published at Hospital Medicine 2011, May 10-13, Dallas, Texas. Abstract 308. Journal of Hospital Medicine. 2011; 6 (suppl 2). Accessed April 6, 2020.

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