thyroid gland diseases in children riga olena khnmu
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Thyroid Gland Diseases in Children
Riga OlenaKhNMU
Excretion of iodine ( in urine)
100-200 μg/l – normal level 201-299 μg/l – increase level > 300 μg/l - increase of intake in
food Deficiency: < 20 μg/l – severe 20-49 μg/l - moderate 50-99 μg/l - mild
The steps of thyroid hormone synthesis
Monoiodotyrosin (MIT)
Diiodotyrosin (DIT)
1 molecula MIT + 2 DIT → thyroxin T4
1 molecula MIT + 1 DIT → triiodothyroxinT3
Under thyroperoxidase control
Peripheral conversation T3 from T4
Both T4 and T3 circulate in plasma bound to the plasma thyroid hormone-binding protein (TBP) Thyroxine-binding globulin.
Thyroid produces only 8 μg of T4 and 4 μg T3 daily. Serum T3 concentration is usually low
because of reduced conversation from T4.
The factors that destroyed of conversation T4→T3 systemic disease starvation, anorexia surgical intervention newborn period gerontological period glucocorticosteroids β-adrenoblocks amiodarone (cordaron) propylthyouracil
Action of thyroid hormones
Genomic effects: the interaction of TH and its receptors is believed to precede other cellular events of messenger RNA and specific protein synthesis
Action of thyroid hormones
Maturation of the CNS: lack of TH in the first year or two results in decreased brain cell size and number. Myelinization of axons is retarded leading to abnormalities and dendritic arborization
Action of thyroid hormones
Maturation of the skeletal and dental system
Maintenance of oxidative metabolism and heart production
Control of temperature production
TH differentiates all tissues and organs
Diagnostic of Thyroid gland disease
Visual & palpating method Investigation of thyroid function
(basal level of freeT3 ,freeT4) Functional tests (TSH) USG, radiography, scanning, etc. Biopsia
Diagnostic of Thyroid gland disease
Serological tests:*Markers of autoimmune disease
(antibodies to thyroglobulin, thyroperoxidase, to TSH-receptors)
*Markers of cancer (thyroglobulin, calcitonin)
Goiter WHO (1994)
0 – goiter is absent I – goiter isn’t visualized, but it’s
size less than distal phalanx of thumb
II – goiter is palpated & visualized
Functional condition of Thyroid influence may be as
Euthyroidism Hypothyroidism hyperthyroidism
Нypothyroidism
Hypothyroidism - syndrome with particular or total deficiency T3 and T4 or theirs acts to target cells
Classification of hypothyroidism
Disturbances PRIMARY - defects of biosynthesis
of T3, T4 due to pathology of thyroid gland
SECONDARY - decreasing T3, T4 due to deficiency of TSH (pituitary) or TRH (hypothalamus) or Resistance of receptors for T3, T4
Classification of hypothyroidism
OnsetCongenital Acquired (rare)
Classification of hypothyroidism
Clinic & biologic data Latent (subclinical) T3 -N, T4 –N, TSH > 10 mU/l Manifestation of disease due to ↓
T4 (at first) & ↓ T3
Complicate
ETIOLOGY OF CONGENITAL HYPOTHYROIDISM Primary hypothyroidism Thyroid
dysgenesis (aplasia, hypoplasia, or ectopic gland)
Inborn error of thyroid hormone synthesis, secretion, or utilization
Maternal goitrogen ingestion or radioactive iodine treatment
Iodine deficiency (endemic goiter) Autoimmune thyroiditis
ETIOLOGY OF CONGENITAL HYPOTHYROIDISM (c’d)
Hypothalamic or pituitary hypothyroidism
Pituitary aplasia Septo-optic dysplasia PIT1 mutation (deficiency TSH, GH,
Prol PROP-1 mutation (deficiency TSH, GH,
Prol,Lh,FSH,ACTH) Thyrotropin unresponsiveness
SYMPTOMS OF CONGENITAL HYPOTHYROIDISM
There is a tendency towards prolonged gestation with 1/3 of pregnancies lasting 42 weeks or more
Prolonged jaundice Lethargy Constipation Feeding problems Cold to touch
SIGNS OF CONGENITAL HYPOTHYROIDISM
Skin mottling and Dry skinUmbilical hernia and Distended abdomen
JaundiceMacroglossia
Large fontanels Wide sutures Hoarse cry
Muscle HypotoniaSlow reflexes
Minority of CH Puffy myxedematous face Depressed nasal bridge with hypertelorism Large protruding tongue with an open
mouth Cold, motted skin Short neck Palpebral fissures are narrow Short fingers Fat deposits between neck and shoulders Hiar is coarse, brittle and scanty Hiarline reaches far down on the forehead
DIAGNOSTIC STUDIES IN HYPOTHYROIDISM
Thyroid scan – 99mTc or 123 IT3 resin uptake
Bone ageTSH !!!Free T4 – if hypothalamic- pituitary
hypothyroidism suspected TBG – if TBG deficiency suspectedAnti-thyroid antibodies – if history of
maternal thyroiditis
Biochemical hallmarks of CH
Low serum T4 and T3 with evaluated TSH (primary)
T3 –normal, T4 ↓- severe or longstanding T4 –normal but TSH is elevated –
compensative CH, transient or subclinical T4↓ but TSH normal- congenital TBG-
deficiency or hypothalamic-pituitary hypothyrodism
Biochemical hallmarks of CH
Other: Elevated serum cholesterol Elevated creatinphosphokinase Hyponatriemia
Instrumental data
Slightly decrease heart rate and amplitude of R wave (ECG)
Increase projection period, left ventricular wall diameter, decrease LV chamber size and decrease cardiac output (EchoCG)
Low-amplitude diffuse slowing (EEG)
Treatment L-thyroxin
Preterm 8 – 10 μg/kg 0-3 mo 10 – 15 μg/kg 3-6 mo 8 – 10 μg/kg 6-12 mo 6 – 8 μg/kg 1-3 years 4 – 6 μg/kg 3-10 years 3 – 4 μg/kg 10-15 years 2 – 4 μg/kg > 15 years 2 – 3 μg/kg
ETIOLOGY OF ACQUIRED HYPOTHYROIDISM Chronic lymphocytic (Hashimoto`s)
thyroiditis (CLT) Subacute thyroiditis (De Quervain`s) Goitrogens (iodide, thiouracil, etc.) Thyroidectomy or ablation following
radioactive iodine Infiltrative disease (e.g., cystinosis,
histiocytosis X)-systemic disease
ETIOLOGY OF ACQUIRED HYPOTHYROIDISM (c’d) Hypothalamic or pituitary disease Congenital thyroid disorders, e.g., ectopia,
may not decompensate until later childhood and thus may appear acquired
Peripheral resistance to thyroid hormones, including receptor defects
Jatrogenic (propylthiouracil, methimazole, iodides, lithium,amiodarone)
Hemangiomas of the liver
SYMPTOMS OF ACQUIRED HYPOTHYROIDISM Slow growth Puffiness Decreased appetite Constipation Swollen thyroid gland Lethargy Drop in school performance Cold intolerance Galactorrhea Menometrorrhagia
SIGNS OF ACQUIRED HYPOTHYROIDISM
Short stature Decreased growth velocity Increased upper to lower segment
ratio Delayed dentition Myxedema or mildly overweight Goiter
SIGNS OF ACQUIRED HYPOTHYROIDISM (c’d)
Delayed reflex return Dull, placid expression Pale, thick, carotenemic, or cool skin Muscle pseudohypertrophy Delayed puberty or precocious
puberty Treatment –same CH
Chronic thyroiditis Hashimoto disease
Clinical presentation: goiter with euthyroidism Thoxic thyroiditis Hypothyroidism with or without
thyromegaly Dysphagia, pain or pressure
sensation in the neck, cough and headache have been reported
Diagnosis Hashimoto disease
T4 total and free, serum TSH Biopsy Antibodies test: antithyroglobulin antibodies to
thyroperoxidase antimicrosomal test
Causes of thyrotoxicosis
Congenital: transient, neonatal Graves’ disease
Acquired: Graves’ disease Functional adenoma Thyroid cancer TSH-secreting pituitary tumor Jatrogenic
(Graves disease)
Diffuse toxity goiter - autoimmune pathology with prolonged elevation T3 & T4 and enlagment of Thyroid gland, and in 70% cases with ophthalmopathy
Hyperactivity, irritability, altered mood
Fatigue, weakness Goiter Tachycardia and ↑ pul’s pressure Nervousness
Graves disease (symptoms)
Graves disease (symptoms) Palpitations Weight loss with ↑ appetite Heat intolerants, increase sweating Increased stool frequency Thirst and polyuria Oligomenorrea, loss of libido
Graves disease (sings) Sinus tachycardia, atrial fibrillation Tremor, hyperkinesis Warm, moist skin Palmar erythema, onycholysis Hair loss Muscle weakness & wasting Heart failure, psychosis (rare)
Graves disease Ophthalmopathy
A feeling of grittiness & discomfort in the eye
Retrobulbar pressure or pain Eyelid lag or retraction Periorbital edema, chemosis,
scleral injection
Graves disease Ophthalmopathy (c’d)
Proptosis Extraocular muscle dysfunction Exposure keratitis Optic neuropathy
Treatment of thyrotoxicosis Thionamids: mercasolyl 0.3-0.5 mg/kg
divided 2 -3 times – 14-21 days , than supportive dose – 2.5-7.5 mg/daily 1 time
Β ab (anaprilin) 1-2 mg/kg divided 3 times
Euthyrosis – mercasolil 5-10 mg/daily with L-thyroxin 25-50 μg/daily
Surgical treatment
Thyroid storm (crisis) Sudden onset Fever Profuse diaphoresis Flushed warm skin Tachycardia Weakness, lethargy and confuson Coma Nausea, vomiting, diarrhea Enlarge liver, jaundice
Thyroid storm (crisis) NaJ 1-2 g daily IV immediately Propylthiouracil 200-300 mg every 6
hours by nasogastric tube Β ab (propranolol) 0.1 mg/kg IV or 4
mg/kg orally Dexamethasone 1-2 mg every 6 hours Supportive: correction of
dehydratation, antipyretics, digitalis to patients with cardiac failure
GOOD LUCK!