Insulin autoimmune syndrome in a patient with ANCA-associated glomerulonephritis

The patient, a 66-year-old woman, who has been under hemodialysis due to antineutrophil cytoplasm autoantibody (ANCA)-associated glomerulonephritis since 2003, was hospitalized because of cold sweating, general fatigue, and somnolence. Hypoglycemia (43 mg/dL) with markedly elevated insulin level (1410 μU/mL) and insulin antibody was found in her serum. She was diagnosed as having insulin autoimmune syndrome. She has not taken any medication that might cause insulin autoimmune syndrome. The possible association of ANCA-associated glomerulonephritis with insulin autoimmune syndrome is discussed.