A patient with intravascular lymphoma presenting with cerebral infarction and a high serum MPO-ANCA level

A 74-year-old woman presented with multiple brain infarctions, an inflammatory reaction, and a high serum titer (414 U/ml) of myeloperoxidase-specific antineutrophil cytoplasmic antibody (MPO-ANCA) with no hematological abnormalities. After the inflammation and ANCA titers were resolved with steroid therapy for suspected microscopic polyangiitis, hemophagocytic syndrome developed. Biopsies revealed non-Hodgkin’s intravascular lymphoma (IVL). The flare of IVL with negative serum ANCA suggested that the initial high serum MPO-ANCA had not originated from tumor cells.