14. Hypothyroidism - diagnosis, classification, clinical manifestation, treatment Flashcards
hypothyroidism can have what types of onset and what are the accompanying symptoms ?
early onset in newborn = failure to thrive , mental retardation decrease in fine motor skills = non reversible
in adults =
= reversible
what is the classification of hypothyroidism ?
primary = most common late stage of hashimotos thyroidectomy transient hypothyroidism in de quervian SEVERE iodine deficient hypo or aplasia of thyroid amiodarone - high level of iodine
secondary
pitutory gland adenoma
pituitary ablative therapy
tertiary
hypothalamic dysfunction = rare
peripheral resistance to thyroid hormones
how do we classify hypothyroidism ?
according to TSH levels
subclinical = TSH slightly increases - no symptoms
mild - TSH increased
OVERT - TSH strongly increased
what are the signs and symptoms of hypothyroidism ?
hypertension
decrease in the basal metabolic rate Cold intolerance cold skin ========== CNS: depression, slowed cognition
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musculoskeletal
proximal muscle weakness
carpal tunnel syndromes ============ skin dryness, alopecia brittle nails Myxedema: due to accumulation of glycosaminoglycans and hyaluronic acid within the ECM of the dermis → nonpitting edema Initially, edema is pretibial, but as
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Lipid profile: ↑ LDL
, ↑ triglycerides
============ GIT Constipation weight gain ========== cardiovascular Bradycardia
Hyperprolactinemia:
↑ prolactin production is stimulated by TRH → suppression of LH, FSH, GnRH, and testosterone and stimulation of breast tissue growth
amenorrhea
galactorrhea
decreased libido
erectile dysfunction , impotency
why do people with hypothyroidism have mild anemia ?
1) impaired haemoglobin synthesis = thyroxine deficcny
1) iron def= menorrhagia and menorrhea , impaired internal absorption of iron
3) flate def - impaired folate absorption
4) pernicious anemia
what are the metabolic changes of hypothyroidism ?
dyslipidemia = high LDL
decreased activity of enzymes which convert LDL and decreased response of LDL receptors
= WEIGHT GAIN AND COLD TOLERANCE
what is the diagnosis of hypothyroidism ?
for primary :
high TSH , T3 AND T4 low
antibodies for hashimoto
ultrasound
radioactive iodine uptake - decreased in thyroiditis caused
biopsy - hashimoto , de quervian
===========
secondary = TSH low , T3 AND T4 LOW ASWELL
check other pirtory hormones
what is the treatment of hypothyroidism ?
levothyroxine (LT4)
given once daily
if cardiovascular disease or 70 years old = start with low dose and increase
what are the drugs which is not good combination with LT4 ?
bile acid binding resins ,
iron containing compounds - decrease absorption of levothyroxine from GI
increase metabolism of LT4-
phenytoin , carbamezapine
what is the definition of subclinical hypothyroidism
TSH levels are elevates
and NOMAL FT4
they have transition to hypothyroidism so assessment every 6 months
ALWAYS TREATED IN PREGNANCY
why should the LT4 level of a pregnant women be checked continuously ?
deficiency go thyroid hormones can be harmful for the baby for relies on the thyroid hormones - for neurological maturation
so always starts LT4 even if SUBCLINICALhypothyroidism
complication of hypothyroidism ?
myxoedema coma - myxoedema and coma do not have to be seen
but there is
altered mental status low body temperature. Low blood sugar, low blood pressure, hyponatremia, hypercapnia, hypoxia, slowed heart rate,
IV combination of levothyroxine and liothyronine plus IV hydrocortisone until adrenal insufficiency is ruled out
