Summary of clinical features of TMA associated with IFN-β referred to the National UK TMA Center
| Clinical feature . | Number of cases, n = 8 . |
|---|---|
| Underlying disease | |
| Relapsing remitting multiple sclerosis | All |
| Presenting features | |
| Microangiopathic hemolytic anemia | All |
| Emergency/critical care admission | All |
| Severe/malignant hypertension | All |
| Renal failure | All |
| Additional organ involvement* | All |
| Specialist investigation | |
| Reduced ADAMTS13 activity† | None |
| Atypical HUS mutations‡ | None |
| CFH, CFI, C3, CF, CD46, THBD | |
| Immune reaction against IFN-β (neutralizing antibody titer >20 NU/mL)† | None |
| Chronicity | |
| Length of treatment >5 y | All |
| TMA with chronic changes on renal biopsy‡ | All |
| Dose dependence | |
| Treated with >50 μg/wk | All |
| Weight in bottom quartile | All |
| Final diagnostic evaluation | |
| Direct drug-induced TMA | All |
| Clinical feature . | Number of cases, n = 8 . |
|---|---|
| Underlying disease | |
| Relapsing remitting multiple sclerosis | All |
| Presenting features | |
| Microangiopathic hemolytic anemia | All |
| Emergency/critical care admission | All |
| Severe/malignant hypertension | All |
| Renal failure | All |
| Additional organ involvement* | All |
| Specialist investigation | |
| Reduced ADAMTS13 activity† | None |
| Atypical HUS mutations‡ | None |
| CFH, CFI, C3, CF, CD46, THBD | |
| Immune reaction against IFN-β (neutralizing antibody titer >20 NU/mL)† | None |
| Chronicity | |
| Length of treatment >5 y | All |
| TMA with chronic changes on renal biopsy‡ | All |
| Dose dependence | |
| Treated with >50 μg/wk | All |
| Weight in bottom quartile | All |
| Final diagnostic evaluation | |
| Direct drug-induced TMA | All |
Summary of clinical features of new and index cases6 of IFN-associated TMA in multiple sclerosis patients referred to the national TMA center in Newcastle. Full clinical details of all cases are in supplemental Table 1. Following diagnostic reevaluation the clinical phenotype of the cases was uniformly consistent with a direct drug-induced TMA.2,24
Neurological involvement, 4/8 cases; cardiac involvement, 6/8 cases.
Data available for 6/8 cases.
Data available for 7/8 cases.