Parrott DSA CMDT Flashcards
Thyroid tests- screening
- serum TSH!!!
- free T4
Thyroid tests- for hypothyroidism
- serum TSH
- antithyroglobulin and antithyroperoxidase ab’s (Hashimoto)
Thyroid tests- for hyperthyroidism
- serum TSH!!!
- T3 or free T3 iodine uptake and scan
- antithyroperoxidase and antithyroglobulin ab’s
- TSI
Thyroid tests- for thyroid nodules
- fine-needle aspiration (FNA) biopsy
- I uptake and scan (cancer is usually cold)
- Tc scan (vascular vs avascular)
- ultrasonography (assist FNA biopsy)
hypothyroidism- common manifestations
- nonspecific- weight gain, fatigue, lethargy, depression, weakness, dyspnea on exertion, constipation, dry skin, cold intolerance
- bradycardia, thin brittle nails, thinning of hair, peripheral eema, yellowing of skin, puffy fae
- palpably enlarged goiter
hypothyroidism- lab
- screening- TSH
- primary- inc TSH, dec T4
subclinical hypothyroidism
- normal serum FT4 with a serum TSH above range
- transient
hypothyroidism- tx
- levothyroxine!!!
- myxedema crisis- need larger dose of levothyroxine
hypothyroidism- monitoring and optimizing tx
- elevated TSH indicates the need for a higher dose of levothyroxine
- many drugs interfere with levothyroxine!
hypothyroidism- elevated serum TSH level- tx
- confirm that the pt is taking the levothyroxine as directed and doesnt have angina
- exclude malabs of levothyroxine
- usually indicates a under replacement of levothyroxine
hypothyroidism- normal serum TSH level- tx
-some pts with CAD or recurrent a fib- lower doses of levothyroxine- keep TSH in high-normal range
hypothyroidism- low serum TSH level- tx
- low (0.04-0.4)- inc risk of a fib and osteoporosis
- suppressed (< 0.03)- if hyperthyroidism sx’s- reduce dose of levothyroxine
Hyperthyroidism- causes
- Graves disease
- postpartum and silent thyroiditis
postpartum thyroiditis
- in first 12 months afer delivery
- in 5% of postpartum women
- over 80% have antithyroid ab’s
- hyperthyroidism followed by hypothyroidism (22%)
- thyrotoxicosis (30%)
- hypothyroidism (48%)
- recurrence with more pregnancies!
silent thyroiditis
(subacute lymphocytic thyroiditis)
-spontaneously or triggered by medications
hyperthyroidism- sx’s, signs
- nervousness, heat intolerance, inc sweating, fatigue, m cramps, weight loss
- menstrual irregularities
hyperthyroidism- thyroid examination
- Graves dz- diffusely enlarged thyroid, often with a bruit, asymmetric
- subacute thyroiditis- enlarged, tender
- toxic multinodular goiter- palpable nodules
hyperthyroidism- cardio pulm manifestations
- forceful heartbeat, PACs, sinus tachycardia
- exertional dyspnea
- A fib or a tachycardia (8%)
- pulm HTN (49%)
hyperthyroidism- lab findings
- FT4, T3, FT3, T4, thyroid resin uptake- inc
- TSH dec
- Graves- TSI
- subacute thyroiditis- inc WBC, ESR, CRP
- hyperthyroidism during pregnancy- elevated T4 and FT4 and dec TSH
- amiodarone- inc T4 and FT4, dec TSH
Graves disease- tx
- propranolol
- Thiourea drugs (methimazole, PTU)
- iodinated contrast agents
- radioactive iodine
- thyroid surgery
hyperthyroidism from thyroiditis- tx
- propranolol (during hyperthyroid phase)
- ipodate sodium (corrects elevated T3 levels)
- NO thioureas (TH production is low)
subacute thyroiditis
(de Quervain thyroiditis, granulomatous)
- after a URI
- summer
Hashimoto thyroiditis- sx, signs
- diffusely enlarged, firm, nodular thyroid gland
- sx’s related to levels of TH
- depression, fatigue
- dry mouth
subacute thyroiditis- sx, signs
- painful enlargement of thyroid gland
- pain may radiate to ears
- fever, fatigue
- hypothyroidism lasts 4-6 months
Hashimoto- lab
- antithyroid peroxidase or anti thyroglobulin ab’s
- TSH inc
- ab’s assoc with celiac dz (15%)
- T4 is usually higher than T3 levels- passive release of stored H (vs Graves dz- T3 more elevated)
subacute thyroiditis- lab
-ESR elevated, antithyroid ab’s low
Hashimoto- tx
- levothyroxine (if hypothyroidism)
- large goiter and normal/elevated TSH- shrink the goiter by admin levothyroxine to dec the serum TSH- suppressive doses of T4!!
Subacute thyroiditis- tx
- aspirin!!!
- thyrotoxic sx’s- propranolol
- iodinated contrast agents- decreases serum T3- improves thyrotoxic sx’s
- sodium ipodate- given until serum FT4 levels return to normal
hypoparathyroidism- caused by?
- acquired (after thyroidectomy)
- APECED (Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy)
- heavy metals- copper, iron
hypoparathyroidism- sx’s, signs
- hypocalcemia- tetany, m cramps, carpopedal spasm, altered mental status, tingling of hands, feet
- chvostek’s sign
- trousseau sign
hypoparathyroidism- lab
- low calcium, high phosphate
- low urinary calcium, normal alk phos
- low PTH
Hyperparathyroidism- caused by
- primary- adenoma, hyperplasia, carcinoma
- MEN
- secondary- chronic kidney dz
Hyperparathyroidism- clinical findings- skeletal
- low bone density- wrist
- osteitis fibrosa cystica- fractures
- brown tumors
- arthralgias, bone pain
hyperparathyroidism- clinical findings- hypercalcemia
- neuromuscular- paresthesias, m cramps and weakness, dec DTRs
- CNS- HA, fatigue, depression
- CV- HTN, prolonged PR interval, shortened QT interval
- renal- hypercalcemia-induced nephrogenic DI; calculi
- GI
- pruritus
- calcium in corneas, arteries (calciphylaxis)
hyperparathyroidism- complications
- long bone fractures
- UTI- stone and obstruction
- MEN type 1 assoc
drugs contraindicated in hyperparathyroidism
-avoid thiazide diuretics, large doses of Vit A, calcium-containing antacids or supplements
osteoporosis- bone densitometry
DXA (dual-energy x-ray absorptiometry)
-determines the bone density of the lumbar spine, hip, distal radius
T score:
> -1: normal
-1 to -2.5: osteopenia (low bone density)
< -2.5: osteoporosis
< -2.5 with a fracture: severe osteoporosis
osteoporisis- tx
- diet- protein, total calories, calcium, vit D
- exercise
- meds
osteoporosis- essentials of dx
- fracture propensity of spine, hip, pelvis, and wrist from demineralization
- serum PTH, calcium, phosphorus, and alk phos usually normal
- serum 25-hydroxyvitamin D levels often low as a comorbid condition
osteoporosis- meds
- Vit D and calcium
- sex H’s- prevents osteoporosis in hypogonadal women and men
- Bisphosphonates- inhibit osteoclast-induced bone resorption
- Denosumab (ab that inhibits maturation of preosteoblasts into mature osteoclasts)
- Teriparatide- analog of PTH
- SERMs (selective estrogen R modulators)- prevent osteoporosis- Raloxifene for postmenopausal women
- Calcitonin- not as effective; analgesic for vertebral fractures
Osteomalacia- essentials of dx
- painful proximal m weakness (esp pelvic girdle); bone pain and tenderness
- dec bone density from defective mineralization
- inc alk phos, dec 25-hydroxy-vitamin D, hypocalcemia, hypocalciuria, hypophosphatemia, secondary hyperparathyroidism
- classic radiologic features
osteomalacia- kids and adults
- kids- rickets
- adults- osteomalacia
osteomalacia- etiology
- vit D def and resistance- most common cause!!
- def calcium intake
- phosphate def
- aluminum toxicity
- hypophosphatasia
- fibrogenesis imperfecta ossium
phosphate deficiency- genetic disorders
- AD- mutation in FGF23
- X-linked- mutation in PHEX endopeptidase
- AR- mutation in DMP1
- all 3 cause high serum FGF23 levels!!
phosphate deficiency- tumor-induced osteomalacia
-mesenchymal tumors secrete FGF23 and cause hypophosphatemia due to renal phosphate wasting
hypophosphatasia
(severe def of bone alkaline phosphatase)
-rare genetic cause of osteomalacia that is commonly misdx’ed as osteoporosis
Paget Disease of Bone (Osteitis Deformans)- essentials of dx
- often asx
- bone pain may be the 1st sx
- kyphosis, bowed tibias, large head, deafness, and frequent fractures
- serum calcium and phosphate normal; alk phos elevated; urinary hydroxyproline elevated
- dense, expanded bones on radiographs
Paget Disease of Bone (Osteitis Deformans)- where?
UK and European migration
- usually dx in pts > 40 yo
- unkown cause; may be a genetic component
Paget Disease of Bone (Osteitis Deformans)- sx and signs
- often mild and asx
- mult bones in 72%- pelvis, vertebrae, femur, humerus, skull
- pain- 1st sx- aching, deep, worse at night
- affecfts long bones proximally then goes distally
- bones become soft- bowed tibias, kyphosis, “chalk stick” fractures
Paget Disease of Bone (Osteitis Deformans)- tx
-bisphosphonates- IV zoledronate is tx of choice
