Chapter 149 - Metabolic Bone and Inflammatory Joint Disease

Question 1

osteopetrosis

Answer 1

osteoclast deficiency

autosomal recessive form: lethal in childhood, ATP6i mutation

autosomal dominant version: most common, CnCL7 (chloride channel 7) mutations

presentation:
fracture, complications following tooth extraction, pancytopenia
CNS issues - hearing, vision loss 2/2 cranial n compression
hypocalcemia

imaging: obliteration of medullary cavity
- alternating sclerotic and lucent bands
- erlenmeyer flask deformity (also seen in gaucher)

Question 2

hypercalcemia of malignancy lab findings

Answer 2

1. hypercalcemia
2. normal to high phosphorous
3. LOW PTH

Question 3

Paget disease

Answer 3

disorganized bone formation. usually isolated to one skeletal area

strong genetic tendency/autosomal dominant - SQSTM1

acute increase in pain in known pagetoid region (without fx) -> malignant transformation - most common in pelvis, femur, humerus

labs: increased alkaline phosphatase, normal calcium, increased urine n-telopeptide/yroxyproline

cant give teriparitide to pagets -> increased risk of secondary sarcoma