One subset of patients with retinitis pigmentosa has immunologic defects.

Immunological evaluation of 20 patients with retinitis pigmentosa (RP) revealed significantly diminished circulating T-lymphocyte numbers and function and a high frequency of serum antibodies to human IgG in comparison with a healthy matched control population. However, these differences were due to severely abnormal results found in one subpopulation within the total patient group; this dichotomy was unrelated to the mode of inheritance or clinical severity of RP in individual patients. Thus, RP appears to be a syndrome rather than a disease and includes a form characterized by defective immunity. Whether this is involved in the pathogenesis of the retinal degenerative process is conjectural.