Transient neonatal diabetes in a moderate preterm neonate: tailoring therapy beyond insulin

Abstract

Congenital diabetes is a rare form of neonatal diabetes mellitus (NDM), typically resulting from monogenic mutations that impair pancreatic beta-cell development, insulin secretion, or function. It is broadly classified into two types: transient NDM (TNDM), which typically resolves within weeks to months but may relapse later in life, and permanent NDM (PNDM). Unlike type 1 or type 2 diabetes, congenital diabetes manifests within the first six months of life and often requires a distinct diagnostic and therapeutic approach. We present a rare case of congenital diabetes in a 32-week preterm female neonate, born small for gestational age, who developed persistent hyperglycemia from the first day of life. Initial management with intravenous fluids and insulin therapy yielded limited glycemic control, raising the suspicion of insulin resistance. Based on clinical grounds, oral sulfonylurea therapy was initiated, leading to rapid glycemic stabilization and notable catch-up growth. This case underscores the importance of early recognition of monogenic diabetes, the potential effectiveness of sulfonylureas even in preterm neonates, and the need for a high index of suspicion in atypical neonatal hyperglycemia. We describe the clinical course, diagnostic evaluation, and successful management strategy in this infant.