Table 2 Complement analytes in the WUSM COVID-19 cohort.

Statistical tests for comparison were done using the Mann-Whitney U test. Values are represented as medians (interquartile range).

Non-ICU
(n = 62)
ICU (n = 72)P
sC5b-9 (ng/ml)559.5
(343.3–813.0)
715.4
(448.5–1084.0)
0.0335
C5a (pg/ml)*635.0
(471.9–892.6)
918.4
(666.7–1081)
0.034
iC3b:C3 ratio*0.56 (0.51–0.65)0.70 (0.57–1.39)0.002
Factor B, ng/ml*21,606
(17,834–26,853)
25,840
(20,544–32,832)
0.033
AP hemolytic
activity, %
85.0
(76.0–102.5)
81.0 (74.5–90.0)0.2519
Ba, ng/ml*1191
(901.3–1981)
3112
(2022–6612)
<0.0001
Factor D, ng/ml*4640.3
(3659–9887.3)
6622.5
(4308–10,854.1)
0.166

*C5a, iC3b:C3 ratio, Factor B, Ba, and Factor D were measured in 48 patients, among whom 26 needed an ICU admission and 22 did not.

†AP hemolytic activity was performed in 38 patients (21 ICU and 17 non-ICU) on the basis of the availability of samples.