Pathological synopsis

 Vascular changes in small muscular arteries

• concentric intimal hyperplasia
• medial hyperplasia with luminal narrowing
• prominent myxoid change
• extravasated red blood cells
• some foamy histiocytes
• no evidence of thrombotic microangiopathy.

References

 Selby DM, Rudzki JR, Bayever ES, Chandra RS. Vasculopathy of small muscular arteries in pediatric patients after bone marrow transplantation. Hum Pathol. 1999 Jul;30(7):734-40. PMID: #10414490#