This is the first case report to demonstrate that UCTD may induce renal glucosuria in a patient with a heterozygous mutation in SLC5A2. This case suggests that during the process of diagnosing renal glucosuria, in addition to familial renal glucosuria (FRG), autoimmune diseases, though rare, should also be taken into consideration. The gene discussed is SLC5A2; the disease is Renal glucosuria.