A case of hyperosmolar nonketotic coma occurring during chemotherapy using cisplatin for gallbladder cancer

A 61 year-old woman was admitted to our hospital because of an abdominal tumor. She was diagnosed with recurrent gallbladder cancer, and treated with cisplatin (CDDP). On day 6, after the 1st cycle of chemotherapy, she developed confusion and suddenly became comatose. She was diagnosed as having hyperosmolar nonketotic coma (HNC) on day 7. She had no history of diabetes mellitus. She recovered from HNC after 3 days of treatment with continuous infusion of 0.45% saline and moderate amounts of insulin. HNC may be a complication of CDDP chemotherapy in patients with malignancy. Early diagnosis and appropriate treatment is necessary for HNC occurring during chemotherapy for malignant disease.