 - Patients with a known parathyroid disorder; active thyroid disorder except stable, replaced hypothyroidism; Cushings syndrome; uncontrolled diabetes mellitus could have unexpected fluid, electrolyte and mineral shifts; sarcoidosis elevated calcitriol levels from granulomata; hypercalcemia of malignancy i.e., PTHrP-mediated or extensive bone mets;known tumor-induced osteomalacia; Pagets disease of bone; known X-linged or autosomal dominant hypophosphatemic ricketsosteomalacia; known renal tubular disease e.g., Fanconis syndrome; chronic GI malabsorption sydrome. 