C3 and lupus nephritis: Patients with various classes of lupus nephritis were more often men (39 vs. 6%, p = 0.06), had higher blood pressure (133/82 vs. 117/70 mmHg, p < 0.03) and seemed more frequently to have low serum levels of C3 (92 vs. 65%, p = 0.10) (171) and C4 (57) if they had deposits in the glomerulus.