Circulating immune complexes and the complements system in lupus nephropathy.

From a group of 75 patients with systemic lupus erythematosus (SLE), 30 patients with lupus nephropathy presenting concomitant changes of the CIC level, of the complement system (C3 and C1q factors) and proteinuria were chosen for the study. In these 30 patients, no statistically significant correlation was observed between CIC level and the value of serum complement. Low serum complement was observed in 89% of the cases while low complement values associated with increases of the CIC level were observed only in 57.8% of the cases. From the values of the C3 and C1 complement factors it results that in 76.6% of the cases of lupus nephropathy the activation of complement was achieved in the classical way. The value of proteinuria presented no significant correlation with any of the parameters investigated. The serum immunogram presented varied aspects and the components of the CIC structure revealed a great diversity of this structure.