Babesiosis as a Cause of Atraumatic Splenic Injury: Two Case Reports and a Review of Literature

Abstract

We present two cases of Babesia -induced splenic injury at a single institution. In the late summer, two patients presented with left-sided abdominal pain radiating to the shoulder. They were both found to have hemolytic anemia, thrombocytopenia, and acute splenic infarction on imaging. Blood smears showed intracellular ring forms consistent with Babesia spp. and low parasitemia (<1%). Diagnosis was confirmed by PCR for Babesia microti . Both patients improved with azithromycin and atovaquone, without blood products or surgical intervention. Several weeks following treatment, repeat blood smears revealed no parasites. Splenic infarct and hemorrhage have been previously reported as rare complications of babesiosis. However, given the steady rise in Babesia microti cases in the USA, even these rare complications will become more prevalent. We review both the diagnosis and management of Babesia -induced splenic complications, which can be challenging in patients with low-level parasitemia. Clinicians should consider babesiosis as a cause of atraumatic splenic injury.

Autochthonous Babesia canis infections in 49 dogs in Germany

“…To the best of our knowledge, splenic infarction associated with B. canis infection, as suspected in 2 of our cases, has not been reported previously. Interestingly, splenic infarction is described in human patients as a rare complication of B. microti infection 46,47 . In addition to vascular obstruction caused by adhesion of infected erythrocytes to the endothelium, endothelial damage and rapid splenic enlargement associated with sequestration of Babesia ‐laden erythrocytes and platelets are possible pathomechanisms.…”

“…Interestingly, splenic infarction is described in human patients as a rare complication of B. microti infection. 46 , 47 In addition to vascular obstruction caused by adhesion of infected erythrocytes to the endothelium, endothelial damage and rapid splenic enlargement associated with sequestration of Babesia ‐laden erythrocytes and platelets are possible pathomechanisms. Splenic rupture also has been described in this context.…”

Babesia spp. en derrame peritoneal canino

“…A esplenomegalia ocorre devido à intensa infiltração de hemácias parasitadas no baço e a hepatopatia, resultante de lesões por hipóxia ou por citocinas inflamatórias, e liberação de peptídeos vasoativos, ocasionando vasodilatação, aumentando a permeabilidade vascular e, consequentemente, a ascite e estase circulatória (Fortes, 2004;Monteiro, 2011;Soulsby, 1988;Urquhart et al, 1998). Além disto, infarto e hemorragia esplênica em decorrência da babesiose vem sendo relatados na literatura, como causas de sangramento intracavitário (Sung et al, 2021), o que poderia justificar a presença dos merozoítos de Babesia spp. livres na cavidade abdominal.…”