Thrombotic microangiopathy due to acquired complement factor I deficiency in a male receiving interferon‐beta treatment for multiple sclerosis

Abstract

Aims Interferon‐beta (IFNβ), the most widely prescribed medication for multiple sclerosis, is generally considered safe. Nevertheless, rare serious and/or life‐threatening side effects have been reported such as thrombotic microangiopathy. A few mechanisms have been proposed to explain how interferon causes thrombotic microangiopathy, but immunological studies have been unable to pin this phenomenon down to a single pathophysiologic pathway. The aim of this article was to report a new mechanism explaining Interferon beta related thrombotic microangiopathy. Methods We report thrombotic microangiopathy in a 28‐year‐old male receiving interferon‐beta treatment for multiple sclerosis. Results After three years of starting interferon beta therapy, the patient presented with malignant hypertension causing seizures, rapidly progressive renal failure requiring haemodialysis and haemolytic anaemia. Corticosteroid and plasma exchange sessions permitted haemolysis control. Nonetheless, the patient remained hemodialysis‐dependent. Exploration of the complement system found a complement factor I deficiency whose activity normalized at the control carried out after 2 years. Conclusion IFNβ treatment may cause complement factor I deficit, which can lead to thrombotic microangiopathy and severe renal failure.

Disease-modifying therapies and hematological disorders: a systematic review of case reports and case series

“…Many drugs seem to be related to the occurrence of this event, including carbamazepine, ceftriaxone, mirtazapine, oxaliplatin, penicillin, quinine, quinidine, rifampicin, NSAIDs, vancomycin and diuretics (112). Many case reports not included in this review described the occurrence of thrombotic microangiopathy during the treatment with IFN (113)(114)(115)(116). Although these cases reported the occurrence of thrombocytopenia, they were not considered for inclusion in this systematic review considering that the reduction in platelets' count is not the result of a myeloid toxicity rather than other conditions that are not related to suppression of myeloid function.…”

Data_Sheet_1.docx

“…Many drugs seem to be related to the occurrence of this event, including carbamazepine, ceftriaxone, mirtazapine, oxaliplatin, penicillin, quinine, quinidine, rifampicin, NSAIDs, vancomycin and diuretics (112). Many case reports not included in this review described the occurrence of thrombotic microangiopathy during the treatment with IFN (113)(114)(115)(116). Although these cases reported the occurrence of thrombocytopenia, they were not considered for inclusion in this systematic review considering that the reduction in platelets' count is not the result of a myeloid toxicity rather than other conditions that are not related to suppression of myeloid function.…”