International Journal of Preventive Medicine (Int J Prev Med)2008-7802112013040810781081ENDepartment of Pediatrics Endocrinology, Namazee Hospital, Shiraz University of Medical Sciences, Shiraz, IranDepartment of Pediatrics Endocrinology, Namazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran20130408<p>Permanent neonatal diabetes mellitus (PNDM) is a rare type of diabetes and KCNJ11 gene activating mutation is one of its prevalent causes. We introduced a 4-month-old male infant with poor feeding, restlessness, tachypnea, hyperglycemia, metabolic acidosis, and ketonemia. He was discharged with insulin and after 2 months, KCNJ11 gene mutation was found and treatment was switched from subcutaneous insulin to oral glibenclamide. Now, he is 1 year old with desirable glycemic control; therefore, genetic study is recommended for KCNJ11 gene mutation in such patients because if the mutation is found, treatment can be switched from insulin to sulfonylurea.</p> <strong>Keywords: </strong>KCNJ11, permanent neonatal diabetes mellitus, sulfonylureahttp://ijpm.mui.ac.ir/index.php/ijpm/article/view/1142http://ijpm.mui.ac.ir/index.php/ijpm/article/download/1142/1173