Encephalomyelitis in primary hypogammaglobulinaemia.

The neurological features of 13 patients with primary hypogammaglobulinaemia are described. Seven patients had X-linked agammaglobulinaemia (XLA) and six had common variable immunodeficiency (CVID). Three clinical pictures emerged: (i) a progressive myelopathy (one case); (ii) a myelopathy progressing to an encephalopathy (four cases); (iii) a pure encephalopathy (eight cases). In four patients the encephalopathy was temporarily reversible; the relationship of this to immunoglobulin therapy is unclear. Additional features occurred in some patients. Three had retinopathy interpreted as retinitis pigmentosa, in one of whom the retinopathy resolved. Two patients had a sensori-neural hearing loss and three had features of dermatomyositis; a variable pleocytosis was found in the CSF of nine patients. Imaging revealed atrophic changes in the cerebral hemispheres in eight cases. Ten patients have died, 1-11 years after the onset of the CNS manifestations, and in four autopsies were obtained. Two patients had encephalopathy, one with XLA had evidence of end-stage encephalitis and the other with CVID had a multi-focal leucoencephalopathy. The other two with XLA had leptomeningitis without evidence of encephalitis. Enteroviral infection is probably an important cause of neurological disease in these patients as CSF from seven patients was either positive by polymerase chain reaction (PCR) or by culture for enteroviruses. Other possible mechanisms are discussed.