Splenomegaly, Non-Traumatic Splenic Rupture, and Pancytopenia in Patient with Human Granulocytic Anaplasmosis

Splenic rupture is a well-described complication of babesiosis but is rarely associated with anaplasmosis.

We report a case of a 37-year-old man with no significant past medical history who presented with malaise, myalgias, arthralgias and severe left upper quadrant pain. He was found to have splenic rupture secondary to infection by Anaplasma phagocytophilum. He reported a single tick bite the week prior to onset of his symptoms. On presentation, he was found to have left upper quadrant abdominal tenderness, pancytopenia, and splenomegaly with evidence of splenic rupture and hemoperitoneum on contrasted computed tomography. Blood smear did not demonstrate intraerythrocytic parasites or morulae. His hemoperitoneum was treated conservatively and he was empirically treated for babesiosis. Diagnosis was confirmed by a positive serum PCR for Anaplasma phagocytophilum.

This case study adds to the small number of prior case reports and provides evidence for anaplasmosis-associated splenic rupture.