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ENDOCRINE SYSTEM Hyperthyroidism
HYPERTHYROIDISM (THYROTOXICOSIS)
ETIOLOGY-CLASSIFICATION ................................................................................................................... 1
SYMPTOMS & SIGNS .............................................................................................................................. 3
DIAGNOSIS ............................................................................................................................................. 4
TREATMENT ........................................................................................................................................... 4
THYROID STORM ...................................................................................................................................... 7
TREATMENT ........................................................................................................................................... 8
GRAVES’ DISEASE (DIFFUSE TOXIC GOITER) ........................................................................................... 8
EPIDEMIOLOGY, ETIOLOGY, PATHOLOGY ................................................................................................ 8
SIGNS & SYMPTOMS ............................................................................................................................. 10
DIAGNOSIS ........................................................................................................................................... 14
TREATMENT ......................................................................................................................................... 14
TOXIC NODULAR GOITER ....................................................................................................................... 15
SIGNS & SYMPTOMS ............................................................................................................................. 15
DIAGNOSIS ........................................................................................................................................... 15
TREATMENT ......................................................................................................................................... 16
SPECIAL CIRCUMSTANCES ..................................................................................................................... 16
HYPERTHYROIDISM IN PREGNANCY ...................................................................................................... 16
NEONATAL HYPERTHYROIDISM ............................................................................................................ 16
HYPERTHYROIDISM IN ELDERLY (OCCULT HYPERTHYROIDISM) ............................................................ 17
Hypermetabolism due to circulating free thyroid hormone levels↑
 loss of normal controlling feedback of thyroid secretion.
ETIOLOGY-CLASSIFICATION
Circulating thyroid stimulators
1. Graves’ disease (diffuse toxic goiter)
2. Inappropriate TSH secretion (TSH-secreting pituitary adenoma or pituitary resistance to thyroid
hormone).
3. hCG↑ (turi TSH savybių): molar pregnancy, choriocarcinoma, hyperemesis gravidarum.
Autonomous thyroid hyperfunction
1. Plummer’s disease (toxic solitary or multinodular goiter)
2. Nonautoimmune autosomal dominant hyperthyroidism (mutations in TSH receptor gene →
constitutive receptor activation; manifests during infancy).
3. Lithium-induced goiter (lithium inhibits iodide release from thyroid).
Low thyroid iodine uptake
1. Thyroiditis (destructive changes → excessive hormone release without increased synthesis).
2. Thyrotoxicosis factitia (ingestion of excess thyroid hormone).
3. Iodine-induced hyperthyroidism (JOD-BASEDOW phenomenon - laikina hipertireozė, paskyrus
jodo preparatų [pvz. iodine-rich contrast, amiodarone, iodine-containing expectorants] sergančiam
netoksiniu gūžiu).
4. Ectopic thyroid tissue:
1) metastatic thyroid cancer (functioning follicular metastases)
2) struma ovarii (ovarian teratoma containing thyroid tissue)
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ENDOCRINE SYSTEM Hyperthyroidism
Normal thyroid (cuboidal follicular epithelium with interstitium rich in vascular supply):
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SYMPTOMS & SIGNS
Klinika gali būti neišreikšta senukams ar sergantiems sunkiomis kitomis ligomis.
1. Goiter ± systolic bruit (strumos dydis neatspindi tireotoksikozės sunkumo!)
2. Cardiovascular signs:
 sinus tachycardia (net miegant); atrial fibrillation, extrasystoles (palpitations)
 systolic BP↑ + diastolic BP↓ = widened pulse pressure;
 hyperdynamic cardiac impulse, sistolinis ūžesys ties apex, high-output heart failure.
3. Eye signs: stare, lid lag, lid retraction, mild conjunctival injection.
N.B. infiltrative ophthalmopathy is specific to Graves' disease!
4. Hypersensitivity to heat, increased sweating; warm, fine, moist skin, raudonas dermografizmas.
5. Nervousness, increased activity, anxiety, insomnia; in severe cases, manic / psychotic symptoms
can develop; cognitive deficits (in absence of anxiety) can occur in elderly!
6. Fine tremor (of outstretched fingers), brisk tendon reflexes, weakness-proximal myopathy
(pseudomiastenija).
N.B. ≈ 10% thyrotoxic Asian males experience THYROTOXIC PERIODIC PARALYSIS!
see Mus7 p.
7. Increased appetite, frequent bowel movements (occasionally diarrhea), weight loss, fatigue.
8. Mėnesinių sutrikimai (oligomenorėja) iki nevaisingumo.
 thyroid hormones increase tissue sensitivity to catecholamines – most hyperthyroidism symptoms
(cardiovascular, nervous, eye, skin, diarrhea) are due to adrenergic stimulation;
- catecholamine levels are normal!
- pagrindinė difkė (jei pakilęs AKS) yra FEOCHROMOCITOMA.
Tireotoksikozės sunkumo laipsniai:
Nervų sistema
Pulsas
Svorio kritimas
LENGVAS
Sumažėjęs darbingumas
antroje dienos pusėje
80-100
< 10
VIDUTINIS
SUNKUS
Sumažėjęs darbingumas Prarastas darbingumas,
ryškus raumenų silpnumas
100-120
> 120
10-20
> 20
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ENDOCRINE SYSTEM Hyperthyroidism
Basal metabolic
rate
C/v sistema
ne daugiau +30
+30-60
> +60
n.y.
pulsinis AKS↑, ŠN I
ŠN II-III, Pr virpėjimas
DIAGNOSIS
Confirmation
1. TSH is the best first test - always suppressed (except when etiology is pituitary disorder).
2. FT4↑; if FT4 is normal, FT3 should be measured:
 FT3↑ is usually greater than FT4↑.
 sometimes only T3 is elevated (T3 TOXICOSIS) - early manifestation of ordinary hyperthyroidism
and should be treated as such.
N.B. hipertiroidizmui jautriausia - T3↑
 if FT4 and FT3 are normal, but TSH is suppressed – it is called SUBCLINICAL HYPERTHYROIDISM –
turbūt gydymo nereikia jei asimptomiška, bet reikalingas pastovus sekimas.
Search for etiology
1. Thyroid radioiodine uptake↑ in hormone overproduction states.
2. Thyroid scanning - "hot" nodule (with suppression of rest of thyroid) or diffuse “hot” goiter.
3. Antithyroid antibodies
4. Serum thyroglobulin parallels thyroid hormones, but is low-normal in thyrotoxicosis factitia.
Kiti tyrimai:
1. Blood lipids↓ (ch, LDL)
2. Hyperglycemia
3. Hypercalcemia, alkaline phosphatase↑
TREATMENT
MEDICAL THERAPY
IODINE
 in pharmacologic doses inhibits IODINE ORGANIFICATION and THYROGLOBULIN PROTEOLYSIS
(thyroid hormone release) - Wolff-Chaikoff effect - effect only transitory (lasting only 10-14 days escape phenomenon).
 indications:
1) emergency management of thyroid storm.
2) emergency nonthyroid surgery in hyperthyroid patient.
3) preoperative preparation for subtotal thyroidectomy (iodine decreases thyroid
vascularity; be to, liauka tampa standesnė dėl susikaupusio koloido);
contrast agents (sodium ipodate, iopanoic acid) are potent inhibitors of T4 → T3
conversion; combination with dexamethasone (also potent inhibitor of T4 → T3
conversion) is useful when rapidly preparing patients for thyroid operations
when standard procedures fail.
N.B. iodine is not used for routine treatment of hyperthyroidism!
 usual dosage – 300 to 600 mg/day:
a) 2-3 drops of saturated KI solution po tid or qid
b) 500 mg NaI i/v in 1 L saline q 12 h.
Lugol solution = 10 KI + 5 jodas
 complications:
1) sialadenitis, conjunctivitis, skin rashes.
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2) transient hyperthyroidism (Jod-Basedow phenomenon)
ANTITHYROID DRUGS (THIONAMIDES)
PROPYLTHIOURACIL
100-150 mg q 8 h (pasiekus eutireozę mažinama iki lowest effective amount, e.g. 100-150
mg/d)
METHIMAZOLE (s. THIAMAZOL, MERKAZOLIL)
15-30 mg once daily (pasiekus eutireozę mažinama iki lowest effective amount, e.g. 10-15
mg/d).
CARBIMAZOLE (mėgstamas Europoje) - in vivo greitai hidrolizuojamas į methimazole.
dozavimas kaip methimazole.
Veikimo mechanizmas
 koncentruojasi skydliaukėje.
 esti kaip THYROID PEROXIDASE substratas (competitive inhibitors) – enzimas jodizuoja vaisto
molekules, o ne tyrosyl residues – suminis efektas yra THYROID PEROXIDASE inhibicija (iodide
organification↓ and coupling reaction↓);
PROPYLTHIOURACIL in high dosages also inhibits 5’-DEIODINASE (↓peripheral
conversion T4 → T3).
 neveikia jau susintezuoto tiroglobulino – vaisto efektas pastebimas tik kai sunaudojamas buvęs
tiroglobulinas (t.y. po 2-3 mėn).
 kompensatoriškai daugėja TSH (antithyroid drugs in large doses are goitrogens).
N.B. antithyroid drugs do not block iodide trapping (gydymo pradžioje dėl TSH↑ esti
radioiodine uptake↑↑↑, bet kadangi jodas nepanaudojamas, tai radioiodine uptake greitai tampa
subnormalus).
Indikacijos:
1) Graves’ disease – gali spontaniškai remituoti gydant konservatyviai.
2) preparation of toxic nodular goiter for surgical treatment or 131I therapy (gydant vaistais
remisijų nebūna!).
3) thyroid storm – only PROPYLTHIOURACIL in high doses (800-1200 mg/d) to block T4 → T3.
 skiriami per os.
 maintenance doses can be continued for many years, bet paprastai skiriama 1-2 metus (limited by
toxic side effects).
 monitoringui naudojamas FT4
 permanent remission is achieved in only few adults and in 20 of children (kai kas siūlo “blockand-replace” schemą – žr. Graves’ disease)
Adverse effects:
1) nausea, loss of taste
2) allergic reactions (acceptable to switch to other drug, but there is chance of cross-sensitivity).
3) reversible idiosyncratic agranulocytosis (< 1%) - perspėti kreiptis dėl sore throat, oral ulcers,
high fever.
 unacceptable to switch to another drug - more definitive therapy should be invoked
(radioiodine or surgery).
 agranulocytosis is less common with METHIMAZOLE in dosages < 40 mg/day;
with PROPYLTHIOURACIL, agranulocytosis may occur at any dosage!
PROPYLTHIOURACIL is preferred in pregnancy or breastfeeding - crosses placenta and into breast milk
much less than METHIMAZOLE does.
β-BLOCKERS (pagrinde PROPRANOLOL).
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ENDOCRINE SYSTEM Hyperthyroidism
 malšina adrenerginius simptomus: cardiovascular, mental, tremor, heat intolerance and sweating,
diarrhea, proximal myopathy.
 neveikia į: oxygen consumption (nes pagrinde dėl Na, K-ATPase↑), weight loss, goiter and bruit,
thyroid hormone levels, eye symptoms (stare and lid retraction are predominantly α effects or at
least mixture of α and β effects).
 indications:
1) thyroid storm
2) prompt tachycardia management (for all patients - until relief from antithyroid drugs,
ruošiant operacijai, etc.).
 alternatyva - Ca channel blockers.
RADIOACTIVE IODINE (131I)
- the most common form of therapy in USA.
 treatment of choice for Graves' disease and toxic nodular goiter in all patients (incl. children?).
 emits β and γ radiation.
 dosage is difficult to gauge:
- if sufficient 131I is given to produce euthyroidism, 25% patients will become hypothyroid
1 yr later (galiausiai majority will become hypothyroid).
- if smaller doses are used - higher incidence of hyperthyroidism recurrence.
 tinka visiems atvejams (net jei low iodine uptake).
 efektas gaunamas per 6-12 sav. (per tą laiką skiriami β-blokatoriai);
jei po 12 sav. išlieka hipertireozė, skiriama 2-a radioiodine dozė.
 no proof that radioiodine increases incidence of tumors, leukemia, thyroid cancer, birth defects (if
become pregnant later in life).
 nors dozė gonadoms ne didesnė negu irigoskopijos metu, tačiau vis dar susilaikoma nuo skyrimo
vaikams ir germinacinio amžiaus moterims (pagal Zollinger, 131I neskirtinas iki 35-40 metų
amžiaus); kai kas sėkmingai skiria ir vaikams.
 contraindicated in pregnancy (female patients should always be carefully screened for pregnancy
prior to 131I treatment).
SURGICAL TREATMENT
Indications:
1. Younger patients with Graves' disease:
a) cannot tolerate or recurred after courses of antithyroid drug drugs
b) refuse 131I therapy (jauniems 131I therapy nerekomenduotina)
2. Nodular goiter (toxic adenoma, multinodular).
3. Very large goiters (e.g. compression)
Priešoperacinis paruošimas:
Skydliaukės chirurgija planinė!
 the only indication for emergency thyroidectomy – rapid pressure symptoms due to
intrathyroidal hemorrhage (exceedingly rare situation).
Operation should be performed only after thyrotoxicosis is controlled medically (absence of
symptoms, pulse <100) – risk↓↓↓ of thyroid storm:
2 mėn. iki operacijos - pradėti antithyroid drug
1-2 sav. iki operacijos - pradėti iodine
2 dienos iki operacijos - pradėti hydrocortisone
 skiriant antitiroidinius vaistus, didėja TSH sekrecija → liaukos vaskuliarizacija↑ - todėl iodine
skiriamas būtinai (sumažina liaukos vaskuliarizaciją):
a) saturated KI solution 3 drops  3/d. po (300-500 mg/day).
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b) Plummer schema: Lugol solution (skiesta vandeniu ar pienu) pradedama nuo 15
lašų  3/d ir kasdien pridedama po 3 lašus dozei iki 30 lašų  3/d.
N.B. patient should be euthyroid before iodide is given (iodine-containing contrast agents +
dexamethasone can be used to rapidly restore euthyroidism).
 pilnai kontrolei pasiekti gali būti skiriamas propranolol.
N.B. operation immediately after control of thyrotoxicosis is associated with risk of thyroid
storm – it is preferable to wait 2 months after patient is euthyroid!
Priešoperacinis ištyrimas:
1. Thyroid scan
2. RAIU
3. Fine-needle aspiration biopsy (if gland is asymmetric - reason to suspect neoplasm)
4. Serum calcium and phosphorus levels (baseline parathyroid function)
5. Laryngoscopy (to assess n. laryngeus recurrens)
6. Jei įtariama trachėjos kompresija – lateral neck X-ray
7. Chest X-ray (possible mediastinal extension of the goiter)
Po operacijos:
 kelias dienas tęsiamas PROPRANOLOL (T1/2 of thyroid hormones is 5-10 days)
 sekti [Ca2+] kasdien 3 paras; jei simptominė hipokalcemija - skirti CaCl2 arba Ca gliukonatą i/v,
vit. D, kai kas siūlo ir CaCO3 1,5-2 g/d per os.
 po 4-6 sav. kontroliniai thyroid function tests.
Early complications (operacinis mirtingumas - apie 0%):
1. N. laryngeus recurrens pažeidimas (jei abipus - asfiksija → pastovi tracheostoma arba vedeginių
kremzlių lateralinė fiksacija Teflono injekcijomis)
2. N. laryngeus superior r. externus pažeidimas
3. Oro embolija
4. Hipoparatiroidizmas-tetanija (ankstyvas per pirmas 24 val. po operacijos - jei pašalintos visos
prieskydinės liaukutės)
5. Thyroid storm
6. Hematoma su kvėpavimo takų kompresija → skubi revizija operacinėje (ar dar palatoje)
7. Tracheomaliacija ir asfiksija → tracheostomija
8. Infekcija
Late complications:
1. Recurrence (< 10%)
2. Hypothyroidism (directly related to extent of surgical treatment – rekomenduojama palikti bent 4-5
g. skydliaukės audinio; not big problem - effectively treated with life-long thyroid replacement).
3. Vocal cord paralysis
4. Hypoparathyroidism
THYROID STORM
- ūmus adrenerginis “sprogimas” organizme, skydliaukės hormonų kraštutinai sensibilizuotame
katecholaminams:
1) fever (up to 40C)
2) marked weakness and muscle wasting
3) extreme restlessness with wide emotional swings; confusion, psychosis, coma
4) hepatomegaly (mild jaundice), vėmimas, diarėja
5) cardiovascular collapse, shock
 results from untreated hyperthyroidism.
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 precipitated by infection, trauma, surgery (esp. thyroid), embolism, diabetic acidosis, toxemia of
pregnancy or labor.
N.B. thyroid storm is life-threatening emergency (mortality >50%)!
TREATMENT
1. PROPYLTHIOURACIL smūginė dozė (800-1200 mg/d per os or by gastric tube)
2. IODINE – mainstay of treatment, bet skiriamas tik ≥ 1 val. po propylthiouracil (to prevent thyroid
hormone synthesis↑):
a) NaI 1-2 g i/v/i per 24 val.
b) saturated KI solution 15 drops/d in 3-4 divided doses
3. PROPRANOLOL 1 mg lėtai i/v, kartoti kas 4 val. (arba 40 mg ×4/d per os)
4. Dextrose i/v
5. Hydration & electrolyte correction
6. Hydrocortisone 300 mg/d i/v
7. Vėsinimas - acetaminophen, cooling blankets
8. O2
9. Sedacija - chlorpromazine 50-100 mg i/m
10. Digoxin (if necessary)
GRAVES’ DISEASE (DIFFUSE TOXIC GOITER)
EPIDEMIOLOGY, ETIOLOGY, PATHOLOGY
- the most common cause of hyperthyroidism.
Nėščioms ir kūdikiams – žr. žemiau (HYPERTHYROIDISM IN PREGNANCY, NEONATAL HYPERTHYROIDISM).
Autoimmune disease – polyclonal antibodies against thyroid TSH receptor → continuous thyroid
stimulation (todėl antikūniai dar vadinami thyroid-stimulating immunoglobulins, TSI)
 TSI seniau vadinti long-acting thyroid stimulator (LATS).
 TSI randami 90 sergančiųjų.
 TSI titras koreliuoja su ligos aktyvumu ir sumažėja po sėkmingo gydymo!
 TSI esti IgG klasės – praeina placentos barjerą ir sukelia laikiną hipertiroidizmą naujagimiams
(žr. žemiau, neonatal hyperthyroidism).
 sometimes associated with other autoimmune disorders (insulin-dependent diabetes mellitus,
vitiligo, premature graying of hair, pernicious anemia, collagen diseases, polyglandular deficiency
syndrome).
 turbūt egzistuoja ir TSH poveikį blokuojantys Ak – suminis poveikis į skydliaukę priklauso nuo
jų ir TSI titrų santykio.
Įrodytas paveldimas komponentas.
Išprovokuoti gali psichiniai sukrėtimai.
Pikas 20-50 metų.
Moterys : vyrai = 10 : 1
Histologija
 diffuse hyperplasia of follicular epithelium – follicles small, tall epitheliocytes form infoldings
into follicular lumen.
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 in stroma – vascularity↑, lymphocytic infiltration.
Prominent infoldings of hyperplastic epithelium, colloid vacuoles next to epithelium:
Hyperplasia of follicular epithelium with nuclear irregularity, colloid depletion; focal lymphoid
aggregates (arrow):
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ENDOCRINE SYSTEM Hyperthyroidism
SIGNS & SYMPTOMS
 chronic course with remissions and relapses.
TIREOTOKSIKOZĖ + SPECIFINIAI SIMPTOMAI (autoimmune manifestations of Graves'
disease):
1. Infiltrative ophthalmopathy, s. exophthalmos
 pathogenesis: immunoglobulins directed to specific antigens in:
a) extraocular muscles → extraocular muscles push eyeball forward
b) orbital fibroblasts → increased retro-orbital tissue
N.B. antibodies are distinct from those initiating Graves'-type hyperthyroidism!
 orbital pain, irritation, photophobia, lacrimation, double vision (lymphocytic infiltration of
extraocular muscles).
 galimas apakimas (dėl ragenos infekcinės perforacijos, n. opticus kompresinės atrofijos).
 vardiniai simptomai:
Mebiuso (konvergencijos sutrikimas);
Štelvago (retas, nepilnas mirkčiojimas);
Grefe ir Kocherio (baltas skleros ruoželis tarp viršutinio voko ir rainelės sekant žvilgsniu
besileidžiantį ar kylantį [atitinkamai] daiktą).
 frequently worsens or improves independent of clinical course of hyperthyroidism (typical
ophthalmopathy may even be with normal thyroid function - EUTHYROID GRAVES' DISEASE).
2. Infiltrative dermopathy (s. pretibial myxedema - confusing term) - nonpitting infiltration by
proteinaceous ground substance, often pruritic and erythematous (in early stages) and subsequently
becomes brawny.
 usually in pretibial area.
 rarely occurs without ophthalmopathy.
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3. Thyroid acropachy (clubbing):
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DIAGNOSIS
1. Tireotoksikozės tyrimai
2. Ocular examination (visus, akiplotis, akių judesius, dažyti rageną, orbitos CT).
3. Antibodies:
against thyroid TSH receptor - tiriama retai (except in last pregnancy trimester - to predict neonatal
Graves' disease; antibodies readily cross placenta to stimulate fetal thyroid!) – reikalingi specialūs
tyrimai:
a) displacement of 125I-labeled TSH from purified thyroid cell membranes
b) stimulation of cAMP generation by cultured thyroid cells (thyroid-stimulating antibody
assay).
antithyroid peroxidase (present in most patients) and antithyroglobulin (present in fewer patients) measurements are readily available in most laboratories!
TREATMENT
General startegy:
young - drugs then surgery;
elderly - radioiodine.
ANTITHYROID DRUGS
 after discontinuing 1-2-yr course only 16-40% of patients will remain in remission.
 remisiojos tikimybė didesnė:
a) younger patients with small goiters
b) mild elevations of T3, T4 before therapy
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c) rapid remission, decrease in gland size following initiation of therapy
 remisijos procentui padidinti pasiūlyta “block-and-replace” schema - antitiroidinis vaistas until
hypersecretion has stopped, then T4 is added (siekiant išvengti strumogeninio TSH pagausėjimo) tęsiama 1 metus, po to 50 seks pastovi remisija.
RADIOIODINE (131I) THERAPY
 nerekomenduotina for children, potential mothers.
 recurrence tikimybė < 10%.
THYROIDECTOMY
Standartinė operacija - bilateral subtotal thyroidectomy.
 vis dažniau atliekama total (or near-total) thyroidectomy - geriau ir lengviau to place patient on
life-long thyroid hormone replacement than to risk recurrent Graves’ disease from thyroid remnant.
 indikacijos:
a) negalima / neefektyvi antithyroid drug therapy
b) negalima / neefektyvi 131I therapy.
OFTALMOPATIJOS GYDYMAS
N.B. galimas apakimas - jei prastėja regėjimas → specialisto konsultacija nedelsiant!
1) galvą laikyti aukščiau (periorbitalinė edema↓)
2) dirbtinės ašaros, 5 guanethidine eye drops (to reduce lid retraction)
3) lateralinė tarsorafija
4) retrobulbarinių audinių apšvitinimas.
5) didelės sisteminių KS dozės, retrobulbarinės KS injekcijos (sudaromas depo)
6) plazmaferezė, imunosupresantai
7) chirurginė dekompresija - su ja neuždelsti!
 infiltrative dermopathy usually remits spontaneously after months or years (topical
corticosteroids can relieve pruritus).
TOXIC NODULAR GOITER
Jei vienas mazgas – toxic adenoma (aprašyta activating point mutations in TSH receptor).
Jei mazgai daugybiniai – Plummer’s disease.
SIGNS & SYMPTOMS
Often patient is still euthyroid, because of pituitary feedback suppresion of normal gland.
Manifestuoja didėjant adenomos aktyvumui, kai normalios liaukos supresija jos nebepajėgia
kompensuoti.
Skirtumai nuo Graves ligos:
1. Suserga vyresni (pikas > 50 metų), lėtesnė progresija.
2. Dominuoja kardialiniai simptomai.
3. Usually do not remit (vs. Graves' disease - may remit spontaneously).
DIAGNOSIS
1. Thyroid scan: hot nodule + sumažėjęs (dėl supresijos) likęs sveikas audinys.
2. Kai diagnozė dar neaiški - supresijos testas – paskyrus egzogeninį tiroksiną, skenuojant mazgas
išlieka karštas;
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paskyrus TSH, skenuojant išryškėja ir sveikas audinys.
TREATMENT
N.B. su vaistais stabilios remisijos pasiekti neįmanoma!
Treatment of choice - totalinė lobektomija (pasiekus eutireozę).
 jei adenomos daugybinės (Plummer’s disease) → (sub)totalinė tiroidektomija.
 priešoperaciniam paruošimui nenaudotini iodides (may worsen hyperthyroidism!).
 alternatyva - 131I terapija (bet pagyjimui reikia gerokai didesnių dozių negu prie Graves’ disease;
privalumas – sveikas audinys esti supresuotas ir nenukenčia – hipotireozė išsivysto retai!).
SPECIAL CIRCUMSTANCES
HYPERTHYROIDISM IN PREGNANCY
Klinika nesiskiria nuo nenėščių pacienčių (bet nepriauga svorio, tachycardia, hyperemesis)
Diagnostika: nėštumo metu fiziologiškai padaugėja TBG → TT4↑ (kad palaikyti normalų FT4) - todėl
diagnostikai tiriama free hormones (FT3 , FT4), TSH – jie normalaus nėštumo metu nekinta.
Gydymas:
 minimalios antitiroidinių vaistų (PROPYLTHIOURACIL 50-100 mg q 8 h is the choice) dozės;
– pasiekus eutireozę papildomai skiriama skydliaukės hormonų, kad vaisiui
neišsivystytų struma (Merck Manual 1999 teigia, kad taip daryti negalima - may mask
effects of excessive PROPYLTHIOURACIL doses on mother and may cause
hypothyroidism in fetus).
 alternatyva - subtotalinė tiroidektomija 2nd trimester metu (po trumpo antitiroidinių vaistų ir
propranololio kurso);
– mother should receive full L-thyroxine replacement (0.15-0.2 mg/day) beginning 24 h
after surgery.
 all iodine preparations (esp. 131I) absoliučiai kontraindikuotina – cross placente (→ fetal thyroid
ablation).
 propranolol vengtinas (potential intrauterine growth retardation, bradycardia, hypoglycemia).
N.B. in Graves' disease, maternal thyroid status does not correlate with fetal thyroid function!
 TSI cross placenta → fetal hyperthyroidism (fetal tachycardia > 160 beats/min, intrauterine growth
retardation indicate fetal hypermetabolism).
 pregnant women with Graves' disease or history of it should receive TSI measurements (žr. Graves’
disease, diagnosis).
NEONATAL HYPERTHYROIDISM
Occurs in infants of mothers with current or prior Graves' disease (TSI cross placenta!):
1. Intrauterine Graves' disease: premature birth or death in utero.
2. Congenital (neonatal) Graves' disease may not become apparent until 7-10 days after birth
(when effect of maternal PROPYLTHIOURACIL subsides).
 infant clears TSI immunoglobulins - disease is usually transient (clearance rate varies disease may last from weeks to months.
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ENDOCRINE SYSTEM Hyperthyroidism
 signs and symptoms: feeding problems, vomiting & diarrhea, failure to thrive,
tachycardia, hypertension, irritability, exophthalmos, goiter, frontal bossing,
microcephaly, premature fusion of cranial sutures (craniosynostosis), developmental
delay.
 mortality may reach 10-15%.
 treatment: antithyroid drug and/or β-blocker.
(monitor closely - discontinue as soon as disease has run its course).
If persistent, hyperthyroidism results in impaired intellect, growth retardation (short stature),
hyperactivity later in childhood.
HYPERTHYROIDISM IN ELDERLY (OCCULT
HYPERTHYROIDISM)
In general, thyrotoxicosis is uncommon in elderly.
KLINIKA
Presentation lacks readily recognizable symptoms and signs of hyperthyroidism - diminished
physiologic reserve is depleted quickly by hypermetabolic stress.
I. Masked hyperthyroidism (65-70%) - one organ system dominates clinical picture:
 most often cardiovascular system - heart failure (cardiomegaly) poorly responsive to digitalis, atrial
fibrillation with slow ventricular response.
 GI involvement - constipation, weight loss with anorexia, hepatomegaly.
 psychiatric manifestations - confusion, psychomotor retardation, chronic depression, apparent
"senile" dementia.
 increased bone Ca turnover (serum Ca↑, bone pain, osteoporosis, frequent fracture).
II. Apathetic hyperthyroidism (10-15%) - apathy and inactivity dominate clinical picture (replace
usual hyperkinesis) - patients look extremely old and wizened but, with treatment, rapidly lose some
wrinkling and become more youthful-looking.
 "characteristic senile appearance" of mild chronic illness, but when afflicted with acute illness or
stress, they "quietly and peacefully sink into coma and die absolutely relaxed death without
activation".
DIAGNOSTIKA
- the same as for younger adults (N.B. thyroxine levels decline 10-20% in normal euthyroid elderly).
GYDYMAS
Radioactive iodine is usually effective (but 50% of patients need temporary prior and subsequent
pharmacologic thyroid suppression).
Panaudota literatūra:
M.KUZIN “Chirurgičeskieje bolezni“, 1995
D.SABISTON “Textbook of Surgery”, 1997
R.A.HOPE “Oxford handbook of clinical medicine”, 1994
J.A.B.COLLIER “Oxford handbook of clinical specialties”, 1995
G.R.McLATCHIE ‘Oxford handbook of clinical surgery”, 1995
Sąsiuvinis “Chirurginės ligos 1, 2“
Pagrindinių piktybinių navikų lokalizacijų diagnostikos ir gydymo pagrindai, 1997
A.JACKEVIČIUS “Onkologija”, 1992
NMS Surgery, Medicine, Pediatrics, Pathological Anatomy, Physiology
Merck Manual 1999
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