Nephrolithiasis from an Unexpected Cause: Phosphaturia

A 54-year-old woman with a history of Type 2 diabetes mellitus and breast cancer with bilateral mastectomy presented to the nephrology clinic for evaluation of nephrolithiasis. She was first diagnosed with nephrolithiasis 3 years prior to arrival requiring lithotripsy and was treated with oral potassium citrate. On physical examination, she was a pleasant woman of middle age with normal blood pressure, regular pulse, and mild costovertebral tenderness bilaterally. Her laboratory studies were remarkable for serum creatinine of 1.29 mg/dL (normal value 0.5-1.2 mg/dL), serum calcium 10.7 mg/dL (normal value 8.8-10.7 Lg/dL), serum albumin 4.9 g/dL (normal value 3.5-5.2 g/dL), serum phosphorus of 2.2 mg/dL (normal value 2.4-4.3 mg/dl), parathyroid hormone (PTH) 23 pg/mL (normal value 15-65 pg/mL), 25(OH) vitamin D of 43 ng/mL (normal value 20-80 ng/mL), 1,25 (OH) vitamin D of 80 pg/mL (normal value 18-78 pg/mL, thyroid-stimulating hormone 1.4 uIU/mL (normal value 0.5-5.7 uIU/mL), PTH-related peptide 0.3 pmol/L (normal value
Source: The American Journal of Medicine - Category: General Medicine Authors: Tags: Clinical Communication to the Editor Source Type: research