Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) permanent neonatal diabetes mellitus ?
    ### Response:
    Permanent neonatal diabetes mellitus is a type of diabetes that first appears within the first 6 months of life and persists throughout the lifespan. This form of diabetes is characterized by high blood sugar levels (hyperglycemia) resulting from a shortage of the hormone insulin.
    