If the increase in blood glucose is caused by abnormal secretion of glucocorticoids due to left renal adenoma, then the blood glucose can usually return to normal after surgical treatment. When a patient has an adrenal tumor, a large amount of glucocorticoids may be secreted after the disease, and the increased glucocorticoids may antagonize insulin and cause abnormal glucose tolerance, which leads to the occurrence of elevated blood glucose. Patients’ blood glucose levels usually return to normal after tumor removal surgery. After surgery, patients should pay attention to diet, exercise, take more vitamins, and maintain a good routine. Patients should go to the hospital for treatment in time to avoid delay. Patients should take medication under doctor’s guidance, not self-medication.