Abstract
A patient fulfilling the diagnostic criteria for systemic lupus erythematosus and presenting with morbid jealousy is described. There was evidence of cerebral lupus. Her physical and mental symptoms responded to a combination of chlorpromazine and steroids. The morbid mental process was probably caused by her physical condition while the content of her disordered thought and behaviour was determined by her introverted premorbid personality, religiosity, unhappy childhood experiences and frustrated desire for children.