Antibodies against C1q Are a Valuable Serological Marker for Identification of Systemic Lupus Erythematosus Patients with Active Lupus Nephritis
Table 7
Significant differences in concentration, sensitivity, specificity, and odds ratio (OR) based on renal involvement in SLE patients .
Sensitivity (%)
Specificity (%)
PPV (%)
NPV (%)
OR (95% CI)
Anti-C1q Ab
30/35 (85.7)
40/60 (66.7)
30/50 (60.0)
40/45 (88.9)
12.000 (4.041−35.632)
Anti-dsDNA Ab
34/35 (97.1)
16/60 (26.7)
34/78 (43.6)
16/17 (94.1)
12.364 (1.561−97.907)
Levels of C3 and C4
34/35 (97.1)
33/60 (55.0)
34/61 (55.7)
33/34 (97.1)
41.556 (5.336−323.637)
Anti-dsDNA Ab, levels of C3 and C4
33/35 (94.3)
31/60 (51.7)
33/62 (53.2)
31/33 (93.9)
23.100 (5.069−105.276)
Abs to C1q and dsDNA
29/35 (82.9)
46/60 (76.7)
29/43 (67.4)
46/52 (88.5)
11.278 (3.994−31.846)
Anti-C1q Ab, levels of C3 and C4
30/35 (85.7)
48/60 (80.0)
30/42 (71.4)
48/53 (90.6)
16.500 (5.485−49.878)
Abs to C1q and dsDNA, levels of C3 and C4
29/35 (80.0)
42/60 (70.0)
29/47 (76.0)
38/48 (80.4)
14.462 (5.157−40.553)
The sensitivity, specificity, and predictive values were calculated using formula described in a previous report [27]. PPV: positive predictive value; NPV: negative predictive value.
