C4A and systemic lupus erythematosus: For this, the differential influence of anti-Smith antibodies (ADS) (p < 0.004) and low C3/C4 (p < 0.03) statistically favored clinical SLE+ determinations, while proteinuria (p < 0.009) and non-scarring alopecia (NSA) (p < 0.015) had elevated representation in UCTD determinations.