Endocrine/Reproductive - Hypothyroidism

Question 1

Causes of congenital hypothyroidism

Answer 1

• Underdeveloped thyroid gland (dysgenesis)
• Fully developed gland that does not produce enough hormone (dyshormonogenesis).
• Very rarely it can be the result of a problem with the pituitary or hypothalamus. This usually occurs without any other problems and the cause is not clear.

Question 2

Diagnosis

Answer 2

• Congenital hypothyroidism is screened for on the newborn blood spot screening test

Question 3

Presentation when not picked up

Answer 3

• Prolonged neonatal jaundice
• Poor feeding
• Constipation
• Increased sleeping
• Reduced activity
• Slow growth and development of mental and physical milestones
• Hypotonia
• Puffy face/macroglossia
• Short stature

Question 4

Aquired Hypothyroidism Definition

Answer 4

Acquired hypothyroidism is where a child or adolescent develops an underactive thyroid gland when previously it was functioning normally.

Question 5

Causes of aquired hypothyroidism

Answer 5

• Autoimmune thyroidism = Hashimotos (MC)
  = This causes autoimmune inflammation of the thyroid gland and subsequent under the activity of the gland
  = Associated with anti thyroid peroxidase (Anti-TPO) Ab + antithyroglobulin Ab
  = Associated with other autoimmune conditions e.g. type 1 diabetes and coeliac disease

Question 6

Aquired hypothyroidism symptoms

Answer 6

• Fatigue and low energy
• Poor growth
• Weight gain
• Poor school performance
• Constipation
• Dry skin and hair loss

Question 7

Treatment

Answer 7

Children will be managed and followed up by a paediatric endocrinologist. Investigations include full thyroid function blood tests (TSH, T3 and T4), thyroid ultrasound and thyroid antibodies.

Levothyroxine orally once a day is used to replace the normal thyroid hormones. Doses are titrated based on thyroid function tests and symptoms.