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25 Cards in this Set
- Front
- Back
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Define the following:
- osteitis fibrosa cystica - osteogenesis imperfecta - osteomalacia and rickets - osteoporosis |
- too much bone resorption from excess PTH
- too little bone deposition + defects in bone matrix formation + Defects in mineralization of bone matrix - combined matrix/mineralization deficiencies. |
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What is Paget's disease of bone?
- hallmark? - sx? |
excess of both osteoclast and osteoblast activity
- disordered bone architecture - normal serum Ca w/ high bone turnover - bone pain, bone deformity, decreased mechanical stregnth, fractures |
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What causes osteogenesis imperfecta?
- sx? |
A group of related disorders due to inherited defects in one of two collagen genes
- diminished bone mass and mechanical strength, leading to multiple fractures and deformities, usually in childhood |
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What are the typical causes of osteomalacia (adults) / rickets (kids)?
- sx? |
Etiology usually involves either vitamin D deficiency, phosphate deficiency, or both
- bone deformities and reduced mechanical strength (pseudofractures) |
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What is the most common metabolic bone disorder worldwide?
- does it involve decreased osteoB actv? increased osteoC actv? |
Osteoporosis
- both |
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Technical definition of osteoporosis based on BMD.
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BMD more than 2.5 S.D. below the mean
of 30 year old controls |
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Is subnormal peak bone mass a risk for osteoporosis?
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yes, because then when aging starts you don't have a 'reserve'
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What is the relationships between Serum 25(OH)D and PTH?
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D-deficient gives you higher PTH.
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What are some modifiable risk factors for osteoporosis?
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Current cigarette smoking
Low body weight (< 127 lbs) Estrogen deficiency Low calcium intake (lifelong) High alcohol intake (3 or more drinks per day) History of other diseases causing secondary osteoporosis |
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HyperparaT
Cushings HyperT Hypogonadism hyperprolactinemia ... call can cause what? |
2ndary osteoporosis
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Should BMD testing be done on all women?
Any particular groups? |
No, only in populations where it influences a tx decision.
Postmenopausal women < 65 yrs with one or more risk factors in addition to menopause All women > 65 yrs (and men > 70 yrs) regardless of additional risk factors Post menopausal women presenting with fractures Women considering therapy for osteoporosis if BMD testing would facilitate the decision Women who have been on postmenopausal HRT for long periods |
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What are routine labs for the eval of osteopenia?
- optional |
Serum Ca, P, Alk P’tase, BUN,
TSH, CBC, 25-OH vitamin D - PTH, cortisol, SPEP, other biochem markers of bone resorption. |
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When should we tx w/ anti-osteoporotic drugs?
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Postmenopausal women and men over age 50 with a prior vertebral or hip fracture
Postmenopausal women and men over age 50 with BMD T-score of -2.5 or lower at the hip or spine Postmenopausal women or men over 50 with T-score between -1.0 and -2.5 at the hip or spine if: 10 year probability (from FRAX®) of hip fracture is > 3%, or 10 year probability of a major osteoporotic fracture is > 20% |
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Does estrogen replacement therapy help slow BMD decline?
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yes, it can.
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Describe the antiEstrogen and the Proestrogen effecs of the following drugs. also give their indication.
- clomiphene - tamoxifen - raloxifene - droloxifene |
- hypoT/pituit; uterus/breast; [fertility]
- hypothal/pituit/Breast cancer; uterus, bone, serum lipids [breast cancer] - Breast cancer; bone, serum lipids [osteoporosis] - breast cancer; bone, serum lipids |
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What do bisphosphonates do? Nomenclature?
- good GI abs? - what does potency depend on? |
b/ hydroxyapatite --> inhib osteoclasts --> long skeletal retention.
- "-dronate" - no, poor. - side chains. |
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Activity of calcitonin?
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Reduces osteoclast activity and
number salmon > human |
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What is PTH (1-34) = Teriparatide?
- admin? - mech? - can be used w/ bisphosphonates? - problems with longterm use? - relative efficacy? |
Anabolic Agent Promoting New Bone Formation (synthetic PTH)
- daily subQ - Increases osteoblast numbers and new bone formation - no, they decrease effect - eventually leads to osteoCLAST actv and bone resorption. - seems to work better while it's working than the ERT and SERMs... at least in their current formulation. Prevents clinical fracture AND radiographic fractures in both spine and hip. |
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What is, by far, the most important determinant of bone mass in both sexes?
- next most important factor in women? |
Age. Peak is at 30.
- estrogen deficiency post-menopause. |
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What is the characteristic pathophysiology of osteoporosis in women immediately post menopause?
- what is the very effective tx at this time? Pathophysio in older women? Slang term for this type of osteoporosis? |
accelerated bone loss via negative calcium balance affecting primarily trabecular bone (vertebral bodies).
- Estrogen replacement Impaired bone formation. "Senile" osteoporosis. Both trabecular and cortical bone are affected. |
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Corticosteroids cause ____ calcium balance at high doses
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Negative --> osteopenia via inhibition of osteoblast activ inhib of GI Ca abs. Also ^ urinary Ca and Phos excretion.
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Thyroid hormones act directly on bone to promote what?
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increased bone turnover; preferentially bone reabsorption --> negative calcium balance
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Growth hormone does what to calcium balance?
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indirectly promotes IGF-1 formation --> stim of osteoblasts --> increased bone growth.
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What is DEXA?
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The preferred technique for measuring bone mass in most diagnostic centers today is dual energy X-ray absorptiometry
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What are SERM's?
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Selective estrogen receptor modulators (SERMs) are synthetic analogs of estrogen that have some of the biological effects of natural estrogen but lack other effects. Drugs in this class include tamoxifen, a drug used to treat breast cancer, and raloxifene, a drug approved for the treatment of osteoporosis
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