Hairy leukaemic cell influx into the cerebrospinal fluid secondary to encephalomyelitis.

A case report of a 53 year old male with hairy cell leukaemia is presented in whom encephalomyelitis caused by toxoplasmosis resulted in an influx of hairy cells into the cerebrospinal fluid following disruption of the blood-brain barrier. These cells subsequently disappeared as the barrier reformed. It is suggested that the presence of hairy cells in the cerebrospinal fluid is a secondary self-limiting phenomenon.