Clear cell meningioma causing Castleman syndrome in a child.

This 11-year-old boy presented with a rare case of Castleman syndrome caused by a clear cell meningioma manifesting as persistent fever of unknown origin, 2 years after glomerulonephritis. Laboratory investigation of the patient showed an increased inflammatory reaction, as well as elevated polyclonal gamma globulin titer and serum level of C-reactive protein. Magnetic resonance imaging revealed a tumor at the cerebellopontine angle. Neurosurgical intervention was performed under the presumptive diagnosis of Castleman syndrome caused by intracranial tumor. Histological examination of the tumor verified that it was clear cell meningioma with infiltration of lymphoplasma cells, and surgical removal resulted in complete resolution of the patient's symptoms and biochemical abnormalities. The present case of clear cell meningioma manifesting as Castleman syndrome shows that the possibility of a brain tumor should be considered in patients presenting with fever of unknown origin, anemia, hypergammaglobulinemia, or other systemic illness.