I have often seen patients with chronic kidney disease who have an abnormal serum protein electrophoresis (SPEP) or free light chain (FLC) ratio and are referred to hematology before a nephrology evaluation. Many undergo an extensive hematologic workup, including a bone marrow biopsy, before their kidney disease is assessed. If the biopsy is negative for multiple myeloma or other hematologic malignancy, the abnormal monoclonal studies are attributed to monoclonal gammopathy of undetermined...

As a nephrologist, I frequently see patients with kidney stones, and one finding that appears with striking regularity on metabolic evaluations is hypocitraturia, defined as urine citrate <320 mg/day. In large-scale urine studies, hypocitraturia is now the third most common metabolic abnormality in stone formers, surpassed only by high urine calcium (>250mg/day) and low urine volume (< 2 L/day), significant risk factors for kidney stone formation (1). Over the past two decades, the prevalence...

Chronic Kidney Disease—Mineral Bone Disease (CKD-MBD) encompasses a spectrum of skeletal, vascular, and mineral metabolism abnormalities,...