A 70-year-old female from southern Massachusetts, USA, was admitted to the intensive care unit with septic shock and acute respiratory distress syndrome (ARDS) after 3 days of acute febrile illness. She had undergone splenectomy at the age of 5 related to trauma from a traffic accident. Laboratory studies reveled pancytopenia, acute renal insufficiency, increased lactate dehydrogenase, depressed haptoglobin, and elevated liver enzymes with indirect hyperbilirubinemia. Prothrombin time and activated partial thromboplastin time were both elevated and fibrinogen level was low, consistent with disseminated intravascular coagulation (DIC). A direct anti-globulin test was negative. A thin blood smear with oil immersion showed intraerythrocytic polymorphic ring forms (Figure 1, arrows) morphologically consistent with Babesia species and the presence of Howell-Jolly bodies (Figure 1, arrowhead), confirming the history of splenectomy. Real-time DNA-PCR confirmed Babesia microti as the offending parasite. The patient was started on treatment for babesiosis with quinine, azithromycin, and atovaquone. She also received red cell exchange transfusion due to the high level of parasitemia (14% of the erythrocytes) and completely recovered in the next few weeks.