Understanding Neonatal Diabetes: Causes, Symptoms, and Types

Neonatal diabetes is a rare form of diabetes that appears within the first six months of life and results from an infant’s inability to produce enough insulin. Unlike type 1 diabetes—which is caused by autoimmune destruction of insulin-producing cells and usually develops later in childhood—neonatal diabetes is almost always genetic. A mutation in a single gene disrupts the function of the pancreatic beta cells, leading to elevated blood glucose levels from the earliest weeks of life. Because the condition is so uncommon—fewer than 100 cases are currently known in the UK—it can be easily overlooked without careful testing.

The hallmark of neonatal diabetes is early diagnosis before six months of age. Affected infants often show signs of dehydration, poor feeding, and failure to gain weight, all consequences of persistently high blood sugar. Some babies also experienced reduced growth before birth, known as intrauterine growth restriction. Classic “osmotic symptoms” such as frequent urination, excessive thirst, and increased hunger may be present, although they can be hard to recognize in very young infants. In about one-fifth of cases, neurological symptoms such as muscle weakness, developmental delay, or epilepsy occur. When these neurological features accompany neonatal diabetes, the combination is referred to as DEND syndrome.

There are two main forms of the condition: transient neonatal diabetes (TNDM) and permanent neonatal diabetes (PNDM). TNDM, which accounts for roughly 50–60% of cases, usually resolves within the first year of life as insulin production gradually improves. However, many individuals with this form experience a recurrence of diabetes later in childhood or adolescence. The most common cause of TNDM is overexpression of genes located on chromosome 6q24. In contrast, PNDM is lifelong and represents about 40–50% of cases. It is most frequently linked to mutations in genes such as KCNJ11 or ABCC8, which affect the ATP-sensitive potassium (K-ATP) channel essential for normal insulin secretion.

Early genetic testing is crucial, as many infants with K-ATP channel mutations can be treated more effectively with oral sulfonylurea medications rather than insulin injections. With timely diagnosis and appropriate management, most children with neonatal diabetes can achieve good long-term health outcomes.
Understanding Neonatal Diabetes: Causes, Symptoms, and Types