Conclusion
IFNβ treatment can cause complement factor I deficit, which can lead to
a life-threatening TMA and severe renal failure. Hence, IFNβ should be
stopped and corticosteroids and plasma exchange therapy began promptly.
Exploration of the complement system should be considered in the face of
a clinical-biological presentation of IFNβ-induced TMA to clarify the
diagnosis.
In cases of the resistant or relapsing disease, rituximab should be
investigated.