Fulminant CNS perivascular lymphocytic proliferation: association with sargramostim, a hematopoietic growth factor.

Sargramostim (GM-CSF) therapy was instituted in a 49-year-old woman with hepatitis C on chronic interferon alpha-2b therapy. Within two weeks, she developed progressive confusion, lethargy, and gait disturbance. At autopsy 4 months later, diffuse perivascular nonmonoclonal lymphoid infiltrates were demonstrated throughout the central nervous system (CNS). As the use of hematopoietic growth factors in clinical practice increases, potential adverse effects, such as the fulminant CNS lymphocytic proliferation in this patient, are more likely to be encountered.