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Common Thyroid Disorders in
Children
FUNCTIONS OF THYROXINE

Thyroid hormones are essential for:
Linear growth & pubertal
development
Normal brain development &
function
Calcium mobilization from bone
Effects of thyroid hormones
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Fetal brain & skeletal maturation
Increase in basal metabolic rate
Inotropic & chronotropic effects on heart
Stimulates gut motility
Increase bone turnover
Increase in serum glucose, decrease in
serum cholesterol
• Play role in thermal regulation
Thyroid Function: blood tests
TSH
Free T4
Free T3
Dysfunction Thyroid Gland
1. Too little thyroxin – hypothyroidism
a. short stature (acquired), developmental
delay (congenital)
2. Too much thyroxin – hyperthyroidism
a. Agitation, irritability, & weight loss
Hypothyroidism
• Decreased thyroid hormone levels
• Low T4
• Possibly Low T3 too.
• Raised TSH (unless pituitary problem!)
Introduction
Thyroid hormone is essential for the growth and
maturation of many target tissues, including the
brain and skeleton.
As a result, abnormalities of thyroid gland function
in infancy and childhood result not only in the
metabolic consequences of thyroid dysfunction seen
in adult patients, but in unique effects on the
growth and /or maturation of these thyroid
hormone-dependent tissues as well i.e. brain and
bones.
Introduction
Newborns with Hypothyroidism, if not diagnosed and
treated early, are going to have severe mental
retardation besides effects on growth and other
systems.
In contrast, hypothyroidism that develops after the age
of three years (when most thyroid hormone-dependent
brain development is complete) is characterized
predominantly by a deceleration in linear growth and
skeletal maturation but there is no permanent effect
on cognitive development.
Etiology
Ethnic Variation Prevalence
White Infants
Hispanic Infants
Saudi Arabia
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1:4000
1:2000
1:3800
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ETIOLOGY
• CONGENITAL
Hypoplasia(agenesis/dysgenesis)
Familial enzyme defects
(dyshormonogenesis)
Iodine deficiency (endemic
cretinism)
Intake of goitrogens during
pregnancy
Pituitary defects
Idiopathic
Clinical Features of Congenital Hypothyroidism
Finding
%
Lethargy
96%
Constipation
92%
Feeding problems
83%
Respiratory problems
76%
Dry skin
76%
Thick tongue
67%
Hoarse cry
67%
Umbilical hernia
67%
Prolonged jaundice
12%
Goiter
8%
Newborns With Congenital
Hypothyroidism
May have few or no clinical
manifestations
of Thyroid Deficiency
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Congenital Hypothyroidism
The Longer The Condition Goes
Undetected, The Lower The IQ
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Newborn Screening
Success Stories in Pediatric Medicine
 Immunization programs
 Newborn Screening program
 Oral Rehydration Therapy
Pencillin
Newborn Screening
Congenital Hypothyroidism
Clinical
X
suspect
Biochemical (screening)
Optional
Confirm
Lab ( TSH & FT4 )
T scan
B age
Rx & FU
Thyroxin
Growth & D
TSH & FT4
ETIOLOGY /2
• ACQUIRED
Iodine deficiency
Auto-immune thyroiditis
Thyroidectomy or RAI therapy
TSH or TRH deficiency
Medications (iodide & Cobalt)
Idiopathic
Autoimmune hypothyroidism
Hashimoto’s Disease
• Most common cause of hypothyroidism
• Autoimmune lymphocytic thyroiditis
• Antithyroid antibodies:
• Thyroglobulin Ab
• Microsomal Ab
• TSH-R Ab (block)
• Females > Males
• Runs in Families!
Clinical features of Acquired hypothyroidism
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Weight gain
Goitre
Short sature
Fatigue
Constipation
Dry skin
Cold Intolerance
Hoarseness
Sinus Bradycardia
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Hypothyroidism with short stature
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Diagnosis
• High TSH, low T4
• Thyroid antibodies
Treatment of Hypothyroidism
• Replacement thyroid hormone medication:
Thyroxin
Management
Hypothyroidism
High TSH & Low T4
Thyroxine
Dose
10 -15 ug/kg/day
12 -17 ug/kg/day
37.5 – 50 ug/day
Higher dose in
Severe cases
T4< 5ug/dl
Form
Goals
Tablets
Normal T4
In 2 wks
(upper ½ of N)
25-50-75 ug
Crush it, add to
5-10 cc water
Or milk
Normal TSH
In one month
(lower ½ of N)
Treatment
• Follow-Up
- After 2 weeks
(Clinical and Hormonal Evaluation)
- After one month
- Every 2 months for the first year
- Every 4 months for the second year
- Every 6 months thereafter
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Newborn Screening
Congenital Hypothyroidism
• One year after
treatment
• L-Thyroxin 8-12
microgram /Kg/ Day
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Congenital Hypothyroidism
• At 4-Years of Age
• Normal Milestones
• Maintenance Therapy:
L-Thyroxine75
microgram/day
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Congenital Hypothyroidism
• 4 Years After Treatment
• Normal Milestones For His
Age
• His sister was screened
AFTER 24 hr of delivery,
with TSH above 80 mU/L,
Eltroxin was initiated after
diagnosis. She has normal
milestones
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Conclusion
“ There are few instances in the practice
of medicine where the health and welfare
of generations can be positively
affected; early treatment of congenital
hypothyroidism through newborn
screening is one of those instances”
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Hyperthyroidism
• Increased thyroid hormone levels
• High T4 +/- High T3
• Low (suppressed) TSH
Thyroid Ophthalmopathy
Proptosis
Lid lag
Grave’s ophthalmopathy
Hyperthyroidism is a relatively
rare condition in children
Graves disease accounts for more
than 95% of childhood cases of
hyperthyroidism
Causes of hyperthyroidism
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Graves Disease
Overtreatment with thyroxin
Thyroid adenoma (rare)
Transient neonatal thyrotoxicosis
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Hyperthyroidism S&S
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Heat intolerance
Hyperactivity, irritability
Weight loss (normal to increased appetite)
diarrhea
Tremor, Palpitations
Diaphoresis (sweating)
Lid retraction & Lid Lag (thyroid stare)
proptosis
menstrual irregularity
Goitre
Tachcardia
Tremor of the hand
A Color Atlas of Endocrinology p49
Neonatal hyperthyroidism born to mother
with Graves’ disease
A Color Atlas of Endocrinology p51
investigations
• TSH, free T3&T4
• Thyroid antibodies (TSH receptors
antibodies)
• Radionucleotide thyroid scan (increase
uptake)
.
Isotope scan is very important
Graves Disease
I 123 or TC 99m Normal v/s Graves
Treatment
• Three modalities for more than last 50 years
• Radioactive iodine, anti-thyroid drugs &
surgery
• None is optimal
• None interrupts the autoimmune process
• Each has a drawbacks
• No other research options so far
Treatment
Advantage Disadvantage
For who?
I131
Definitive,
Safe
Most patients
Lifelong T4 Rx
Antithyroid May need Side effects,
life long
frequent visits,
Drugs
medication lower rate of
remission,
compliance
Pre RAI Rx,
mild disease
small goiter
Surgery
Toxic nodule,
allergy to
drugs, large
goiter, ? CA
Definitive,
rapid
Side effects,
life long T4 Rx
Hyperthyroidism
• Drug Treatment
– Beta-blockers
– Carbimazole
– PTU (propylthiouracil)
Key Points
• Hyperthyroidism is a relatively rare condition in children
• Graves disease accounts for more than 95% of
childhood cases of hyperthyroidism
• Neonatal Graves disease is rare even among mothers
with known hyperthyroidism
• Only 1 in 70 infants of thyrotoxic mothers has clinical
symptoms
• Treatment options depending on age of the patient,
goiter size, urgency of treatment, RAIU by the thyroid,
physician preference & patient choice
• Radio-active Iodine therapy is safe in children with
thyrotoxicosis
Goiter
• A swollen thyroid
gland
.
Causes of goitre
• Congenital (maternal antithyroid drugs,
maternal hyperthyroidism,
dyshormonogenesis)
• Physiological (puberty)
• Iodine deficiency
• Graves disease
• Hashimoto thyroiditis
• Tumor
Thank You!
Newborn Screening