Cost 
$1,000.00
TAT 
4 weeks
CPT Code 
81402
Test Code 
2147
Test Methods 
Deletion/Duplication analysis
Specimen Types Accepted 
Blood
Saliva
Cultured Cells
Extracted DNA
Genes 
Notes 
If sending saliva, 2 kits are required.

Neonatal diabetes is hyperglycemia that presents at 0-6 months of age (rarely later) and requires insulin.  Approximately 50-60% of cases are considered transient neonatal diabetes [OMIM #601410] and resolve within 18 months.   The remaining cases are considered permanent neonatal diabetes (PNDM) [OMIM #606176].  These patients have low birth weight and require insulin treatment throughout life.  Mutations of the KCNJ11 [OMIM #600937] gene have been identified in patients with PNDM.   Studies have shown that approximately one-third to one-half of all cases of PNDM are due to activating mutations in KCNJ11.

Hyperinsulinemia of infancy (HI), also known as familial hyperinsulinism and persistent hyperinsulinemic hypoglycemia of infancy, is inappropriate oversecretion of insulin despite hypoglycemia.  It usually presents with seizures, hypotonia, poor feeding, apnea, and coma in the neonatal period or infancy, along with high birth weight.  Approximately 5% of individuals with HI have inactivating mutations in KCNJ11

Most patients with KCNJ11 mutations can get better glycemic control without increasing hypoglycemic events by switching from insulin treatment to oral sulfonylureas.

To date no deletions or duplications involving the KCNJ11 gene as causative of neonatal diabetes have been reported.