Late-onset hypocalcemia appearing years after thyroid surgery

We revised four cases of hypocalcemia diagnosed yr after thyroid surgery, including 1 man and 3 women, operated 5-23 yr before the onset of symptoms, which ranged from mild paresthesia to convulsive seizures. Total serum calcium levels ranged from 1.1 to 2.05 mmol/l, and PTH levels were low in the 3 cases in which they were measured. Hypoparathyroidism appearing as late-onset hypocalcemia after extense thyroid surgery is a poorly understood condition, perhaps not as unfrequent as it is considered.