Hypothyroidism and HyperthyroidismPresentation Transcript
Hypothyroidism and Hyperthyroidism in the Elderly Chien Yung-Chang , MD .
Reference range 0.7-1.8 ng/Dl .
Converted to triiodothyronine (T3) .
The thyroid gland is the sole source of T4 .
Free T4 measures the nonprotein-bound circulating T4 .
Normal range 50-120 ng/mL , 5-12 mcg/dL .
Measurement of total T4 is not particularly helpful .
Only 0.03% of T4 circulates in the unbound state .
There is no clinical indication for performing total thyroid hormone measurement .
Normal 0.4-5.5 mIU/L .
Serum TSH will be decreased to<0.1 mIU/L in most hyperthyroid patients .
The findings of a low serum T4 and low TSH mandate a search for pituitary disease .
T3 is more biologically active .
Binding proteins : thyroid-binding globulin , transthyretin and albumin .
T3 thyrotoxicoisis : approximately 5% of clinically hyperthyroid patients with a normal free T4 level .
Measure the uptake of iodine into the thyroid gland .
The iodine isotopes : used to identify nodular thyroid disease , to determine if these nodules are hot ( functioning ) or cold ( hypofunctioning ) , to determine the cause for the hyperthyroid state ( Graves’ disease vs thyroiditis ) and to determine a dose of radioiodine for treatment .
Erythrocyte sedimentation rate
To confirm the diagnosis of subacute ( viral ) thyroiditis in patients with tenderness on thyroid palpation .
The Role of the History in Diagnosing Hypothyroidism
Previous thyroid ablation .
Elevated thyroid autoantibodies .
Thyroid surgery .
Medicatins containing lithium or iodine .
The most common cause of hypothyroidism is autoimmune or Hashimoto’s thyroiditis .
Signs and Symptoms of Hypothyroidism
Less active than usual with loss of interest in things previously enjoyed .
Lethargy , and decreased mobility .
Dry skin .
Sings and Symptoms of Hypothyroidism (continued )
Apathy and psychomotor retardation .
Weakness , arthralgia , myalgia , coarsening of the voice , constipation , edema , weight gain , cold intolerance .
Alveolar hypoventilation => CO2 retention and coma .
The Physical Examination in Hypothyroidism
Hypotension or diastolic hypertension .
Low body temperature and bradycardia .
Facial features that are puffy and coarse .
The skin : dry and cold .
Carotenemia : An orange or yellow tint without scleral icterus .
The Physical Examination in Hypothyroidism ( continued )
Brittle nails and hair , pallor , induration and thickening of skin , periorbital edema , macroglossia , and myxedema .