Rituximab for the treatment of type B insulin resistance syndrome: a case report and review of the literature

Background: Type B insulin resistance syndrome is a rare disease characterized by refractory transient hyperglycaemia and severe insulin resistance associated with circulating anti-insulin receptor antibodies. A standardized treatment regimen for type B insulin resistance syndrome has yet to be established.

Case report: We report the case of a 64-year-old man undergoing haemodialysis for antineutrophil cytoplasmic antibody-associated vasculitis and diabetic nephropathy, who developed rapid onset of hyperglycaemia (glycated albumin 52.1%). Type B insulin resistance syndrome was diagnosed, on the basis of positivity for anti-insulin receptor antibodies and the man's autoimmune history of antineutrophil cytoplasmic antibody-associated vasculitis and idiopathic thrombocytopenic purpura. Although severe hyperglycaemia persisted in spite of corticosteroids and high-dose insulin therapy, rituximab treatment resulted in remarkable improvement of the man's severe insulin resistance and disappearance of anti-insulin receptor antibodies without any adverse effects.

Conclusions: According to a literature review of 11 cases in addition to the present case, rituximab appears to be a safe and effective strategy for the treatment of corticosteroid-resistant type B insulin resistance syndrome.