Hematologic features in myopathy, lactic acidosis, and sideroblastic anemia (MLASA)

The images show findings on the Wright-Giemsa-stained peripheral blood smear (panel A) and bone marrow aspirate (panels B through E) from a 17-year-old with MLASA due to biallelic mutations of the YARS2 gene. Panels F and G show ring sideroblasts in the bone marrow aspirate, and panel H shows bone marrow normoblasts with numerous vacuoles in a transmission electron micrograph (EM). The arrows in panels A and B point to Pappenheimer bodies in red blood cells. The arrows in panels D and E point to cytoplasmic vacuoles in red blood cell precursors; vacuoles are also present in normoblasts in panels B and C. Refer to UpToDate for details of the causes, evaluation, and treatment of sideroblastic anemias.