Bone marrow findings in Pearson syndrome

The images show findings on the bone marrow from an infant with Pearson syndrome (also called Pearson marrow pancreas syndrome [PMPS]). Panels A and B show Wright-Giemsa-stained erythroid and myeloid precursors with numerous cytoplasmic vacuoles. Panels C and D show iron-stained ring sideroblasts. Another hallmark of PMPS is exocrine pancreatic insufficiency. Refer to UpToDate for details of the causes, evaluation, and treatment of sideroblastic anemias.