Table 2.
Incidence rate of aHUS in family members carrying the same complement regulatory gene abnormality of index cases by selected variables
| Variable | Carriers, n | aHUS Cases Among Carriers, n | COP, person-years | Rate, per 1000 person-years (95% CI) |
|---|---|---|---|---|
| All | 186 | 28 | 7595 | 3.69 (2.45–5.33) |
| Gender | ||||
| Female | 94 | 13 | 4013 | 3.24 (1.72–5.54) |
| Male | 92 | 15 | 3582 | 4.19 (2.34–6.91) |
| Age category (yr) | ||||
| 0–9.9 | 23 | 11 | 1764 | 6.24 (3.11–11.2) |
| 10–19.9 | 20 | 1 | 1510 | 0.66 (0.02–3.69) |
| 20–29.9 | 24 | 5 | 1288 | 3.88 (1.26–9.06) |
| 30–39.9 | 16 | 3 | 1084 | 2.77 (0.57–8.09) |
| 40–49.9 | 32 | 2 | 849 | 2.36 (0.29–8.51) |
| 50–59.9 | 27 | 1 | 555 | 1.80 (0.05–10.0) |
| >60 | 44 | 5 | 545 | 9.17 (2.98–21.4) |
| Relationship with index case | ||||
| Parent | 63 | 7 | 3487 | 2.01 (0.81–4.14) |
| Sibling | 59 | 16 | 2143 | 7.47 (4.27–12.1) |
| Offspring | 38 | 4 | 636 | 6.29 (1.71–16.1) |
| Other | 26 | 1 | 1329 | 0.75 (0.02–4.1) |
| Complement abnormality (gene) | ||||
| C3 | 25 | 6 | 931 | 6.44 (2.37–14.0) |
| CFB | 3 | 0 | 118 | 0.00 (0.00–31.3) |
| CFH | 92 | 19 | 3890 | 4.88 (2.94–7.63) |
| CFI | 31 | 1 | 1196 | 0.84 (0.02–4.66) |
| CD46 | 32 | 2 | 1304 | 1.53 (0.19–5.54) |
| Multiple | 3 | 0 | 156 | 0.00 (0.00–23.6) |
| Complement abnormality (classification) | ||||
| VUS | 55 | 4 | 2179 | 1.84 (0.50–4.70) |
| P/LP | 131 | 24 | 5416 | 4.43 (2.84–6.59) |
| Disease recurrence in the family (>2 cases) | ||||
| Yes | 40 | 21 | 1327 | 15.8 (9.80–24.22) |
| No | 146 | 7 | 6268 | 1.12 (0.45–2.30) |
| Severe trigger in the index case | ||||
| Yes | 59 | 1 | 2222 | 0.45 (0.01–2.50) |
| No | 127 | 27 | 5373 | 5.03 (3.32–7.32) |
aHUS, atypical hemolytic uremic syndrome; CI, confidential interval; COP, cumulative observation period; P/LP, pathogenic/likely pathogenic; VUS, variant of unknown significance.