Serum complement (C3 and C4) levels in the Malaysian adult population.

Serum C3 and C4 values were determined in 236 normal adults of three racial groups, using the single radial immunodiffusion techniques. The C3 levels varied from 47 to 119 mg/dl and C4 levels from 16 to 66 ml/dl (mean +/- 2SD). The values were found to be comparable to the normals reported in some Western series. No significant differences in the levels related to sex and race were found.