SUMMARY In a group of 46 patients with retinitis pigmentosa (RP) we studied the presence of circulating immune complexes (CIC) and the alterations in the complement system. Our results showed the presence of CIC in 43.5% of the patients studied, reduced levels of the complement components C3 and C4 (p<0-001), and of the haemolytic activity CH50 (p<0-001) when compared with a control group consisting of a 100 healthy subjects. We found a statistically significant correlation between the values of C3 and CIC (p<0-01), C4 and CIC (p<0.01), and between CH50 and CIC (p<0-001). These findings indicate that the CIC may play a role in the pathogenesis of primary retinitis pigmentosa.

SUMMARY In a group of 46 patients with retinitis pigmentosa (RP) we studied the presence of circulating immune complexes (CIC) and the alterations in the complement system. Our results showed the presence of CIC in 43.5% of the patients studied, reduced levels of the complement components C3 and C4 (p<0-001), and of the haemolytic activity CH50 (p<0-001) when compared with a control group consisting of a 100 healthy subjects. We found a statistically significant correlation between the values of C3 and CIC (p<0-01), C4 and CIC (p<0.01), and between CH50 and CIC (p<0-001). These findings indicate that the CIC may play a role in the pathogenesis of primary retinitis pigmentosa.