Babesiosis on Peripheral Smear 85 M from SE USA, hx splenectomy, IgG4 plasmacytic syndrome: F, chills, profound weakness, R flank pain, hematuria, H/A. diagnosis? Transfusion related babesiosis. babesia microti Ab IFA 1:256, PCR+ Treated with clindamycin & quinine, rbc exchange, post exchange: blood smear neg for intra erythrocytic inclusions, improved clinically and dc on azithro &atovaquone Peripheral smear shown: no shistocytes, +innumerable intra & extra erythrocytic inclusions >10%RBC, +maltese cross +burr cells and spur cells, +rouleoux formation Splenectomized pt with fever: think encapsulated organism: strep pneumonia, H influenza, N meningitis, capnocytophaga canis, bordetella holmesii, babesia microti, malaria Babesiosis ixodes tick(parallel distribution/coinfection w/lyme), more common in NY, NJ, CT, RI, MA, MN, WI Asymptomatic or flu like illness, red cell invasion & lysis: fever, anemia, jaundice, hematuria, renal insufficiency. complications: ARDS and DIC, case fatality: 5% Transfusion transmitted babesia TTB can survive indefinitely in cyroperserved w/ glycerol cryopreservation but in abscess of cryopreservation, killed quickly by freezing. - Indiana University Infectious Diseases Fellowship @IUIDfellowship #Babesiosis #Peripheral #Smear #babesia #microti #clinical