Metabolic bone diseases

• hyperparathyroidism

• uremic bone disease aka renal osteodystrophy

• osteomalacia

• arbitrarily, osteoporosis

• arbitrarily, Paget’s disease

Organs involved in mineral metabolism

• parathyroid

• bone

• kidney

• small intestine

Hyperparathyroidism: causes

• mostly a disease of adults, not of children

• most common cause is parathyroid adenoma

• less commonly, parathyroid hyperplasia

Diagnosis of hyperparathyroidism

• these days, we use a sestamibi test, not surgical exploration

Big parathyroid

• gross: really big—1.5 cm

• big mass is parathyroid adenoma

Hyperparathyroid characteristics

• elevated serum PTH

• accelerated bone turnover

• increased osteoblastic/osteoclastic activity

Tunneling resorption: osteoclasts are resorbing the bone from the trabeculae outwards. keep this picture in mind, because it might come in handy one of these days

Hyperparathyroidism diagnosis: look at the following places

• for whatever reason, distal end of clavicle to detect a hyperparathyroid state

• lamina dura of the teeth

• distal phalanx

• vertebral plates

Category: Pathology Notes