Ch 6 Thyroid disorders

Question 1

hypothyroidism clinical presentation

Answer 1

MOM’S SO TIRED (most are women > 50 yrs)

-Memory loss
-Obesity (mostly fluid, < 10 lbs)
-Menorrhagia
-Slowness (mentally/physically)
-Skin and hair dryness
-onset gradual
-Tiredness
-Intolerance to cold
-Raised BP (modest)
-Energy levels fall
-Depression/Delayed relaxation phase of all reflexes, esp patellar, Achilles

Question 2

most common cause of hypothyroidism?

Answer 2

Hashimotos thyroiditis
-autoimmune, discovered when thyroid is destroyed and nonfunctional

Question 3

other causes of hypothyroidism?

Answer 3

post radioactive iodine (RAI) treatment
-status post (S/P) graves disease treatment
-S/P thyroid cancer treatment with thyroid ablation which causes hypothyroidism
-meds: lithium, amiodarone, interferon, etc (uncommon)

Question 4

hyperthyroidism clinical presentation

Answer 4

SWEATING
-Sweating
-Weightloss (~10 lb muscle & fat)
-Emotional liability (mind racing, memory alteration)
-Appetite increased but losing weight
-Tremor/tachycardia
-Intolerance of heat, irregular menstruation
-Nervousness
-Goiter, GI problems (frequent, low volume, loose stools)

Question 5

most common cause of hyperthyroidism?

Answer 5

Graves disease
-autoimmune, seen with other autoimmune conditions (RA, lupus, vitiligo, celiac disease, T1DM)
-often with new onset tachydysrhythmia, afib, heart failure

Question 6

other causes of hyperthyroidism?

Answer 6

-Toxic adenoma: benign; metabolically active thyroid nodule; present with palpable unilateral thyroid mass but no exopthalmos

Question 7

what is the single most reliable test to diagnose all forms of thyroidism?

Answer 7

TSH (0.4-4.0)
when TSH are WNL, thyroid dz ruled out

Question 7

what follow-up test to confirm of hyper or hypo thyroid?

Answer 7

get Free T4 if abnormal TSH

Question 8

(high TSH, low T4) intervention

Answer 8

hypothyroidism

-give Levothyroxine (Synthroid, Levoxyl, generic)

Question 9

when to have follow up on hypothyroidism after treatment given?

Answer 9

~8 weeks after giving levothyroxine therapy (pt usu notes improvements ~ 1 wk)

Question 10

if TSH STILL elevated after therapy, consider…

Answer 10

-make sure pt takes levo empty stomach, same time everyday
-not be taken w/in 2 hrs of cation (calcium, iron, aluminum, mg, others = reduced drug absorption)

Question 11

(low TSH, high T4) intervention

Answer 11

hyperthyroidism/throtoxicosis

1. Give Beta Blocker (propranolol, nadolol) if not contraindicated for tachycardia/tremor
2. PO methimazole (Tapazole) or PTU
   once euthyroid, offer radioactive iodine (RAI) use = thyroid ablation for hypothyroidism)
3. get endo consult bc of med risk

Question 12

risk of methimazole and PTU use

Answer 12

acute hepatic failure even in healthy liver pts

Question 13

elevated TSH with NL free T4

intervention

Answer 13

subclinical hypothyroidism

-treat with Synthroid if TSH >5 if have:
-goiter
-elevated TPO antibodies
-have sx of hypothyroidism, infertility, pregnancy , or imminent pregnancy

Question 14

after 8 wks of levo therapy for hypothyroidism:

if TSH is >4 then…

if TSH is <0.4 then…

if TSH between 0.4 - 4.0…

Answer 14

TSH > 4, not euthyroid, increase dose 12.5-25, check again in 8 weeks

TSH < 0.5, not euthyroid, decrease dose by 12.5-25, check again in 8 weeks

continue dose, measure TSH in 6 months, then yearly or when symptomatic

Question 15

what is a thyroid nodule?

Answer 15

-palpable thyroid mass, not specific to a diagnosis
>1 cm

Question 16

what is the risk of a palpable thyroid nodule being a malignant lesion?

Answer 16

5% risk of malignant
need biopsy to make sure

Question 17

findings of malignant thyroid nodule?

Answer 17

-hx of head or neck radiation
-size >4 cm
-firmness, non tender on palpation
-fixed position/non mobile
-persistent tender cervical lymphadenopathy
-dysphonia
-hemoptysis

Question 18

if palpate >1cm thyroid nodule, get…

Answer 18

order TSH and thyroid ultrasound (size, location, characteristics)

-if TSH is low (and if excess T4), get nuclear thyroid scan (determines nodule function and structure). If “hot” nodule = radio iodine ablation or surgery. If not “hot” fine needle aspiration

-***if TSH normal, get fine needle aspiration bx