<prompt> Hypoparathyroidism occurs as a result ofa Idiopathic atrophy of parathyroidsb Following surgeryc Thyroditis with secondary atrophy of parathyroidsd All of the aboveacaabbc  <response>: Mostly due to removal of the parathyroid glands or infarction due to vascular injury. Vascular injury is more impoant. Cases usually present 2-5 days after operation with symptoms of hypocalcemia circumoral and fingeip numbness and tingling tetany, carpopedal spasm and laryngeal stridor Treatment with oral calcium and vitamin D supplements IV calcium gluconate may be required in severe cases. 