Part of “CHAPTER 61 – RENAL OSTEODYSTROPHY“

Symptoms of renal osteodystrophy usually appear only in patients with advanced renal failure, although the abnormalities in mineral metabolism occur early in renal insufficiency. Numerous signs and symptoms may appear. The classic symptom of renal osteodystrophy is bone pain, which may be so severe that the patient becomes bedridden. This may occur whether the major abnormality of bone is osteomalacia or osteitis fibrosa. More commonly, the bone pain is vague and localized to the lower back, hips, or legs. Low back pain may arise from collapse of a vertebral body. Chest pain may arise from spontaneous rib fractures. Muscle weakness is often a major associated symptom. The muscle enzymes are normal, and elec-tromyographic findings are nonspecific. In severe cases, electron microscopy of muscle shows local disorganization of myofibrils and dispersion of Z bands.51 Itching is common in
patients with renal osteodystrophy, especially in those with severe hyperparathyroidism. This has been attributed to the deposition of calcium in the skin. Peripheral ischemic necrosis and vascular calcifications may also be found. Acute joint pain and periarthritis, owing to the deposition of hydroxyapatite crystals, may also occur concomitantly with severe hyperparathyroidism. Tendon rupture may ensue from the abnormal collagen metabolism of uremia and has been associated with β₂-microglobulin accumulation. In children, skeletal deformities, bowing of the tibia and femur, and slipped epiphysis are not uncommon. Growth retardation is usual and is due to the combination of malnutrition, acidosis, and osteomalacia. The correction of these abnormalities may improve growth.