Paget's disease of the bone
Posted by dkwinter

     PTH           | Normal
     Ca2+          | Normal
     Phosphate | Normal
     ALP            | Markedly elevated (this is the only difference from osteoporosis)
See also: Bone endocrine diseases
     In most patients, measurement of the total serum ALP activity is an effective an inexpensive test to determine the activity of Paget's disease
     Full extent of the disease is best ascertained by full body bone scan, followed by radiologic confirmation in the documented areas of increased tracer uptake
          Nuclear bone scan is not very specific, but very sensitive in detecting the extent of skeeltal involvement.
     Asymptomatic patients generally DO NOT require treatment
     Indications for treatment incluide:
          1. Bone pain
          2. Hypercalcemia of immobilization
          3. Neurological deficit
          4. High output cardiac failure
          5. Preparation for orthopedic surgery
          6. Involvement of weight-bearing bones (to prevent deformities)
     Treatment of asymptomatic patients with markedly increased disease activity (as evidenced by very high serum ALP) is controversial, although some physicians treat such patients to prevent future complications
     PO or IV Bisphosphonates are the treatment of choice
          An early effect of these drugs is decreased bone resorption
          Activity persists for months to years after treatment is stopped, making these drugs superior to calcitonin
     Treatment with calcium and vitamin D does not have any effect on Pagetic bone. However, vitamin D deficiency can increase bone turnover, which in turn can lead to additional increase in serum ALP