Frequencies of the most common mutations identified in aHUS patients
| Mutated gene/protein . | Type . | Frequency (%)* . | Death or end-stage renal disease 3-10 y after onset (%)† . |
|---|---|---|---|
| Factor H (including CFH/CFHR1 hybrid genes) | Loss of complement regulation | 24-28 | 70-80 |
| MCP (CD46) | Loss of complement regulation | 5-9‡ | <20 |
| Factor I | Loss of complement regulation | 4-8 | 60-70 |
| C3 | Gain of complement activation | 2-8 | 60-70 |
| Factor B | Gain of complement activation | 0-4 | 70 |
| Thrombomodulin | Possibly loss of complement regulation and procoagulative state | 0-5 | 50-60 |
| CFHR1/3 deficiency with anti-factor H autoantibodies | Loss of complement regulation | 3-10§ | 30-70 |
| Diacylglycerol kinase ε | Prothrombotic | 0-3|| | 46 |
| None identified | 30-48 | 50 |
| Mutated gene/protein . | Type . | Frequency (%)* . | Death or end-stage renal disease 3-10 y after onset (%)† . |
|---|---|---|---|
| Factor H (including CFH/CFHR1 hybrid genes) | Loss of complement regulation | 24-28 | 70-80 |
| MCP (CD46) | Loss of complement regulation | 5-9‡ | <20 |
| Factor I | Loss of complement regulation | 4-8 | 60-70 |
| C3 | Gain of complement activation | 2-8 | 60-70 |
| Factor B | Gain of complement activation | 0-4 | 70 |
| Thrombomodulin | Possibly loss of complement regulation and procoagulative state | 0-5 | 50-60 |
| CFHR1/3 deficiency with anti-factor H autoantibodies | Loss of complement regulation | 3-10§ | 30-70 |
| Diacylglycerol kinase ε | Prothrombotic | 0-3|| | 46 |
| None identified | 30-48 | 50 |
Frequencies of the genetic abnormalities have been adopted from a recent review8 and cohort studies.65,66
The values represent averages of the earlier reported values.10,65-67,90
Frequency of the isolated heterozygous MCP (CD46) mutation is usually 7% to 8%, but the mutations are frequently found in combination with other mutations in complement genes (up to 22%).67
Autoantibodies against factor H have been reported in 56% of pediatric aHUS cases in India.68
Diacylglycerol kinase ε mutations are most frequently found in patients with disease manifestation within the first year of life (5%-27% in this population).