Vitamin disorders Insufficient sunlight exposure Kidney: chronic kidney disease, nephrotic syndrome, kidney transplantation Liver disease Nutritional deficiency of vitamin D Malabsorption: aging, excess wheat bran, bariatric surgery, pancreatic enzyme deficiency, orlistat Vitamin D–dependent rickets types I and II Phenytoin, carbamazepine, valproate, or barbiturate therapy (long-term) Dietary calcium deficiency Phosphate deficiency Adefovir therapy Fanconi syndrome, renal tubular acidosis, and alcoholism Intestinal malabsorption Nutritional deficiency of phosphorus Phosphate-binding antacid therapy Renal loss Tumoral hypophosphatemic osteomalacia X-linked hypophosphatemic rickets Other disorders, including paraproteinemias, glycogen storage diseases, neurofibromatosis, Wilson disease Inhibitors of mineralization Aluminum Bisphosphonates Disorders of bone matrix Axial osteomalacia Hypophosphatasia Fibrogenesis imperfecta |