A 45 years old pt underwent PCNL for the side one by another with 4 years interval. On blood investigation it is found to be iPTH 133.9pg/m (14-72pg/ml). Serum calcium normal. Now how to approach for these recurrent stone former pt with raised PTH.

Second point,is there any cutoff or mildly raised calcium or PTH is to be treated. Third point,there are so many pathological entity depicting mild elevation of PTH and borderline serum calcium. How to approach?Please suggest