Immune complexes in retinitis pigmentosa

In a group of 46 patients with retinitis pigmentosa (RP), we studied the levels of IgM, the presence of a rheumatoid factor (RF), the circulating immune complexes (CIC) and the alterations in the complement system. Our results showed increased IgM levels in two patients (226 and 260 mg/dl), the presence of RF in three patients (205, 187 and 80 IU/ml), the existence of CIC in 43.5% of the subjects, reduced levels of the complement components C3 and C4 (p less than 0.001) and of the haemolytic activity CH50 (p less than 0.001) when compared with a control group consisting of 100 healthy subjects. We found a statistically significant correlation between the values of C3 and CIC (p less than 0.01), C4 and CIC (p less than 0.01) and between CH50 and CIC (p less than 0.001).