Neonatal hyperglycemia typically begins in the first ten days of life, and lasts just two to three days. Diagnosis of TNDM and PNDM
The diagnostic evaluations are based upon the following evaluation factors: patients with TNDM are more likely to have intrauterine growth retardation and less likely to develop ketoacidosis than patients with PNDM. TNDM patients are younger at the age of diagnosis of diabetes and have lower insulin requirements, an overlap occurs  between the two groups, therefore TNDM cannot be distinguished from PNDM based clinical feature. An early onset of diabetes mellitus is unrelated to autoimmunity in most cases, relapse of diabetes is common with TNDM, and extensive follow ups are important. In addition, molecular analysis of chromosomes 6  defects,  KCNJ11 and ABCC8 genes (encoding Kir6.2 and SUR1) provide a way to identify PNDM in the infant stages. Approximately 50% of PNDM are associated with the potassium channel defects which are essential consequences when changing patients from insulin therapy to sulfonylureas. TNDM Diagnosis associated with Chromosome 6q24 Mutations
The uniparental disomy of the chromosome  can be used as diagnostic method provide proof by the analysis of polymorphic markers is present on Chromosome 6. Meiotic segregation of the chromosome can be distinguished by comparing allele profiles of polymorphic makers in the child to the childs parents genome. Normally, a total uniparental disomy of the chromosome 6 is evidenced, but partial one can be identified. Therefore, genetic markers that are close to the region of interest in chromosome 6q24 can be selected.
Neonatal diabetes mellitus (NDM) is a disease that affects an infant and their bodys ability to produce or use insulin. NDM is a monogenic (controlled by a single gene) form of diabetes that occurs in the first 6 months of life. Infants do not produce enough insulin, leading to an increase in  glucose accumulation. It is a rare disease, occurring in only one in 100,000 to 500,000  live births. NDM can be mistaken for the much more common type 1 diabetes, but type 1 diabetes usually occurs later than the first 6 months of life. There are two types of NDM:  permanent neonatal diabetes mellitus (PNDM) is a lifelong condition. Transient neonatal diabetes mellitus (TNDM) is diabetes that disappears during the infant stage but may reappear later in life.Specific genes that can cause NDM have been identified. The onset of NDM can be caused by abnormal pancreatic development, beta cell dysfunction or accelerated beta cell dysfunction. Individuals with monogenic diabetes can pass it on to their children or future generations. Each gene associated with NDM has a different inheritance pattern. Symptoms and signs
The first sign of neonatal diabetes is often slowed fetal growth, followed by unusually low birthweight. At some point within the first six months of life, infants with neonatal diabetes tend to experience the classic symptoms of type 1 diabetes: thirst, frequent urination, and signs of dehydration. The timing of symptom onset varies with the type of neonatal diabetes.