Table 6.

Severity of HUS according to sC5b-9 level and genetic background in Shiga toxin–positive patients with HUS

Complement AbnormalitiesAcute PhaseLast Follow-Upa
Dialysis RequiredCNS ManifestationsNo CKDbCKD Stage 1–4bCKD Stage 5bCKD Stage 1–4 versus No CKDCKD Stage 5 versus No CKD
Yes, N (%)No, N (%)OR; 95% CI; P-ValuecYes, N (%)No, N (%)OR; 95% CI; P-Valuecn (%)n (%)n (%)OR; 95% CI; P-ValuecOR; 95% CI; P-Valuec
Increased sC5b-9 (>420 ng/ml)d23/33 (70)15/25 (60)1.5; 0.5 to 4.6; 0.211/13 (85)27/45 (60)3.6; 0.7 to 18; 0.125/36 (69)9/18 (50)1/1 (100)2.3; 0.7 to 7; 0.22.3; 0 to 19; 0.4
Pathogenic variant (n=4)1/42 (2)3/33 (9)0.2; 0 to 2.4; 0.21/17 (6)3/58 (5)1.1; 0.1 to 12; 0.92/48 (4)1/20 (5)1/1 (100)0.8; 0.1 to 9; >0.9955; 1.8 to 1747; 0.06
Variant of uncertain significance (n=8)5/43 (12)3/32 (9)1.2; 0 to 5.8; 0.90/17 (0)8/58 (14)0.2; 0 to 3; 0.27/48 (15)1/20 (5)0/1 (0)3.2; 0.3 to 28; 0.40.5
No variant identified37/43 (86)26/32 (81)1.4; 0 to 5; 0.31/17 (6)11/58 (19)0.3; 0 to 2.2; 0.239/48 (81)18/20 (90)0/1 (0)0.5; 0.1 to 2.5; 0.40.13
  • HUS, hemolytic uremic syndrome; CNS, central nervous system; OR, odds ratio; 95% CI, 95% confidence interval.

  • a Median (First and third quartiles): 47 months (20–65) (n=79 with six lost to follow-up). The CKD stage was documented at 3 year follow-up in 43 patients.

  • b CKD stages according to Kidney Disease Improving Global Outcomes Guidelines 2012 (http://www.kdigo.org/clinical_practice_guidelines/pdf/CKD/KDIGO_2012_CKD_GL.pdf). See Supplemental Material for definition of CKD stages. No patient had CKD stage 4 at last follow-up.

  • c P with Fisher exact test.

  • d Samples before day 14 after admission.