Thyroid Gland/Hypothyroidism Flashcards
Hypothyroidism symptoms
Delayed reflex relaxation time
Thyroid gland is derived from………….begins to develop around…………weeks of gestation , largely completed between……….and………weeks of gestation.
Embryonic floor of pharynx
4
10-20
The recommended daily intake of iodine is………..for adults and ………..for children and …………for pregnant women
Urinary iodine is ………..in sufficient population
150
90-120
200
>10
Primary secretory product of thyroid gland
…………….is the biologically active form of thyroid hormones
T4
T3// 80% from deiodination of thyroid hormones in peripheral tissue ,20% direct from thyroid secretion.
Conversion of T4 toT3
Mainly takes place in liver and kidney.
T4……..>D1+D2………..>T3……..D3……..>T2
لةيكم تفاعل يۆدیگ لەحلقەی خارجی کەنیمنەو ، دووم تفاعل يوديگ لة حلقةي داخلي
Plasma proteins that bound to thyroid hormones
Thyroxine binding globulin TBG
Transthyretin
Albumin
Conditions that increase TBG
Pregnancy
Infection (chronic+active)/Early hepatitis
Biliary fibrosis
Acute intermittent porphyria
HIV infection
Genetic factors
Drugs that increase TBG
Estrogen (OCP , HRT, Tamoxifen).
Methadon /Heroin
Clofibrate
5-fluro-uracil
Drugs that decrease serum T3 +T4
Glucocorticoids +Androgens /(جماعت ادرینال)
L-asparaginase (ALL)
Salicylates =old NSAID /ex/Aspirin
Mefenamic acids =An NSAID
Furosemide /loop diuretic /edema
Anti-seizures (phenytoin - carbamazepine)
Conditions that decrease serum T3 or T4
Genetic factors
Acute +Chronic illness
Liver disease (late)
Total T3 or T4
Are the hormones bound to TBG
Auto regulation of thyroid hormones
Reflects the available levels of iodine.
Wolff-chaikoff effect
Jod-basedow effect
👆iodide ……>hypothyroidism
👆iodide ……>hyperthyroidim
TSH secretion is sensitive to
Plasma free thyroid hormones
وقتی TBG زیاد بوود ،
T3+T4 زیاد دیاردةن
ولكن ……نورماله
TSH
Checking reverse T3 at
Acute illness
ICU
T3 resin uptake test in suspension of👇or👆of TBG
👆TBG
👇TBG
Inversely proportional
(👇T3resin uptake) (👇THBR) (fT4 index=nor)(👆total T4)
(👆T3resin uptake) (👆THBR) (fT4 index=nor)(👇total T4)
Radio-active-iodine uptake
راستةوانةية مع نشاط الغدة الدرقية
Clinical manifestations of hypothyroidism
عرق كردن👇
پوست سةرد و وشك و شاحب
Non-pitting myxedema due to 👆dermal glucosaminoglycan.
Pale with yellow tinge to skin due to carotene accumulation.
تخلف نمو الأضافر والشعر
Diffuse alopecia
Vitiligo /وةك بيماري همراه
👆in aminotransferase
Miscarriage
Carpal tunnel syn
Slow relaxation of tendon reflexes (psedomyotonia).
Reversible cerebellar ataxia
Paranoid or depression
Myxedema coma
Dementia
رةقبوون و تشنج بوون والم عضلات💪
Impaired Hearing
Hoarse voice
Thining of the outer third of eyebrows
If present is specific to hashimoto
Other autoimmune diseases associated with hashimoto disease
Vitiligo
Pernicious anemia
Addison’s disease
Alopecia areata
DM1
Celiac disease
Dermatitis herptiformis
Chronic active hepatitis
RA +SLE+Sjogren’s syn
Classification of hypothyroidism
1/with goiter
A-Hashimoto
B-Nodular goitrous
2/Atrophic =End stage of hashimoto
Autoimmune hypothyroidism
Mean age 60 / incidence 👆with age .
HLA-DR And CTLA-4 , Account for approximately half of the genetic susceptibility to autoimmune hypothyroidism.
Infections :- congenital rubella + hepatitis C virus.
High iodine intake ,by immunologic effects/ IL2 / Interferon alfa.
Pathology of :-
Hashimoto thyroiditis
Atrophic thyroiditis
Oxyphil metaplasia =Askanazy cell
Extensive fibrosis/follicles are absent
Euthyoid sick syndrome =non-thyroidal illness syndrome
Eu=good
الغدة طبيعية والهرمونات غير طبيعية
👆TSH>10/👇T4
👆TSH<10/T4=norm
👇TSH/👇T4
TSH=norm/👇T4
👆TSH<10/👇T4
Primary/overt=clinical
Primary/mild=sub-clinical
Sec
Sec
Sec
س٢٨
مهم
At primary hypothyroidism, should always check
TPO Ab
Primary :-
TPO+Ab
TPO-Ab
Clinical or Subclinical /Always need treatment
Clinical (other causes of hypothyroidism)/subclinical (annual followup)
Follow up for whom are being treated with levothyroxine
فقط TSH هر دوو مانگ جاريگ =٨حفته
مع هر تغير دوز ،هر٦حفته جاريگ
كةسيگ خريكة علاج بةد ، نتائج مخبريةي خاسةوبوود،علائمي خاسةو نيود
لازمة ادامةي علاجةگة بيةد مع نفس جرعه
٣-٦ماه
Radioiodine treatment as a cause of Iatrogenic hypothyroidism
Transient hypothyroidism in the first 3-4 months.
Free T4 is a better measure of thyroid function than TSH.
In secondary hypothyroidism, …………..can’t be used to monitor therapy
TSH
آزمايش قبل علائم خاسةو بوود
همان دوز ادامه تا ٣-٦ ماه
Dose adjustment would be on the basis of ……….Levels
TSH
T4 over treatment
Tachycardia
Atrial fibrillation
👇bone density
Subclinical /no symptoms/TPO+ /
But must treatment
T4=normal
TSH👆>10
ادوية تخلينا نحتاج مقدار اكبر من ليڤو ثايروكسين
Ferrous sulfate
Calcium
PPI =Aluminum hydroxide
Amiodaron
Carbamazepine
Phenytoin
جماعت علاج ثايروكسين ، تا چةند روژ نةخوةن مشكلة نييه
٣ روژ
Half life thyroxine—7days
Before treating subclinical hypothyroidism,
we should confirm that any elevation of TSH , is sustained over a …………of period before treatment is given
3 months
Difference in treatment of
clinical
subclinical
Dose 100
25-50
Follow up, when treating ……>فرق نميكنة
نيهيليمن TSH فرة كةمةو بوود ، كمتر لة يك
Simple non-toxic goiter
Simple=diffuse=No nodule
Non-toxic=No hyperthyroidism
Most common cause of simple goiter
Iode deficiency/ may become hypothyroidism
Simple goiter
Mostly non-symptomatic
Mostly normal laboratory results
Symmetrically enlarged
incidence 👇with age
Simple goiter at pregnancy
Due to 👆iodine demand
Pemberton’s sign when arms are raised above the head
قرمزبوونةوةي سةر كإشارة الى
External jugular venous obstruction
Nodular
حميد و خبيث ي هس
Incidence 👆with age
زيادبووني يۆد، وةيةكجاوة كةدةي هايپر ……>basedow effect
اگر ثابت ورةق يا چسپيدةبوود يان ژان بكةد تفيد في ان تكون خبيثة
Contrast agents and other iodine containing substances should be avoided
