Hi! I had gone through your question and I understand your concern . I would say that all the examination that you have done , the changes I see is cause of medullary nephrocalcinosis.I will exsplain these : -low vitamine D level ( vitamine D deficiency ) , your kidney can t convert vitamine D to its active form Cause in nephrocalcinosis calcium accumulate in the kidneys and demage this function. -increase of calcium level (hypercalcemia) , in nephrocalcinosis patient have increase calcium level in urine and in blood -high parathyroid Hormon ( PTH) it shows that you have hyperparathyroidism that may be the primary cause of nephrocalcinosis .This hormone increse Calcium leves by taking it out of the bones and resorbe calcium in the kidney .High Calcium level accumulate in the organs like kidney and result in nephrocalcinosis - frequent urination is cause of decreased renal concentrating ability, also you may be thirsty. -Hba1c is not to high, it shows that you have a risk of diabetes. Combine all these changes together I would say that you have medullary nephrocalcinosis due to Hyperparathiroidism .If I were you treating doctor would do some examination of your Parathyroides glands ( Imaging ), check you heart , pancreas , blood pressure , and other organs according if you have any other symptoms, and start the treatement : Hydration with isotonic sodium chloride solution, Calcitonine or bisphosphonates ( to inhibit bones resorbtion ),thiazide diuretics , salt restriction., Magnesium,Potassium, steroids , you may need a surgery to remove Your thyroid glands Your treating doctor will take care of all your treatment, have an appointment with him soon. Thank you for using HCM ! If you have any qiestion please feel free to ask. Wish you good health.