Type 1 diabetes mellitus usually has an acute onset, and some patients may have an explosive onset. Immune-mediated type 1 diabetes mellitus, the majority of adolescent patients with a more acute onset, clinical manifestations vary greatly, can be mild non-specific symptoms, typical three more and one less symptom or coma; such as the lack of timely diagnosis and treatment, when a serious lack of insulin, diabetic ketoacidosis can occur. Idiopathic type 1 diabetes mellitus, usually acute onset, beta cell function significantly reduced or even failure, clinically manifested as diabetic ketoacidosis or even acidosis, but the course of the disease beta cell function can be improved to the extent that there is no need to continue insulin therapy for a period of time. Patients with type 1 diabetes are advised to go to the hospital for timely treatment.