A 50 year old man with history of recurrent renal stones and peptic ulcer disease. Urine examination revealed the following findings: He has been taking PPI as prescribed but to no avail. He has presented to emergency with chief complains of difficulty in peripheral vision. Which of the following laboratory workup is required in the evaluation of this patient?

Urine examination reveals calcium oxalate stones CT scan: pituitary macroadenoma. Recurrent calcium oxalate stones s/o hyperparathyroidism Refractory PUD is s/o Zollinger Ellison disease Visual defects with CT findinds is s/o pituitary adenoma The above constellation is suggests diagnosis of MEN 1. Therefore, gastrin (ZES), prolactin (Pituatry adenoma) and PTH (hyperparathyroidism) needs evaluation.