Systemic lupus erythematosus presenting as hypoglycaemia with insulin receptor antibodies and insulin autoantibodies.

A 37-year-old man presented with sweating, confusion, palpitations, hunger and tremor of 3 months duration. The symptoms disappeared after ingestion of food. After 3 months, he suffered from irregular fever, arthritis, rash, photosensitivity, and was admitted to the hospital. His antinuclear antibody, anti-double stranded DNA antibody, anti-smith antibody and lupus erythematosus cell phenomenon were all positive. Urine analysis showed albuminuria; his 24-h urine protein was 4.7 g. During hospitalisation, the patient presented with loss of consciousness three times because of hypoglycaemia. His serum insulin level during the hypoglycaemic episode was high at 490-1080 mmol/L (normal range: 6.00-27.00 mmol/L). He had never received an insulin rejection. Both insulin autoantibody and insulin receptor antibody were positive. Investigations confirmed systemic lupus erythematosus (SLE) with autoimmune hypoglycaemia. High-dose of corticosteroids, chloroquine and cyclophosphamide therapy had resulted in remission of hypoglycaemia associated with resolution of circulating antibodies to insulin and insulin receptor, and improvement in clinical and laboratory features of SLE.