This document discusses different types of hypothyroidism including cretinism, adult hypothyroidism, and myxoedema. Cretinism is fetal or infantile hypothyroidism which can be endemic or sporadic and causes symptoms like a hoarse cry and umbilical hernia. Adult hypothyroidism causes symptoms like bradycardia, cold extremities, dry skin/hair, puffy eyes, hoarse voice, slowed movements, and delayed ankle jerks. Myxoedema is a severe form of hypothyroidism that requires treatment with oral thyroxine, triiodothyronine, or intravenous thyroxine along with corticosteroids and antibiotics.

1. Hypothyroidism

2. Terms
 Adult hypothyroidism
 Myxoedema
 Cretinism

3. Cretinism
 Fetal or infantile hypothyroidism
 Endemic and sporadic
 Sporadic –agenesis ,dyshormonogenesis
 Hoarse cry , macroglossia , umbilical
hernia
 Immediate diagnosis and treatment

4. Adult type
 • bradycardia
 • cold extremities
 • dry skin and hair
 • periorbital puffiness
 • hoarse voice
 • bradykinesis, slow movements
 • delayed relaxation phase of ankle jerks.
The symptoms are:
 • tiredness
 • mental lethargy
 • cold intolerance
 • weight gain
 • constipation
 • menstrual disturbance
 • carpal tunnel syndrome.

5. Myxoedema

6. Classification of hypothyroidism
 Autoimmune thyroiditis (chronic
lymphocytic thyroiditis
1) Non-goitrous: primary myxoedema
2) Goitrous: Hashimoto’s disease

7. Classification
Iatrogenic
 After thyroidectomy
 After radioiodine therapy
 Drug induced (antithyroid drugs,para-
aminosalicylic acid and iodides in excess)

8. Classification
 Dyshormonogenesis
 Goitrogens
 Secondary to pituitary or hypothalamic
disease
 Thyroid agenesis
 Endemic cretinism- Often goitrous and
due to iodine deficiency

9. Dyshormonogenesis
 Deficient enzymes
 Autosomal recessive
 Young patients , thyromegaly , euthyroid
state
 Pendred syndrome – TPO deficiency
goitre , sensorineural deafness ,
abnormal bony labyrinth

10. Investigations and management
 TFT- low T3 , T4 and high TSH
 High titres of TPO antibodies
 Oral thyroxine (0.1 to 0.2 mg/day) or
triiodothyronine (20mcg tds)
 Myxoedema – bolus 500mg of T4 or 10
mcg of T3 oral or IV 4-6 hourly
 Corticosteroids and broad spectrum
antibiotics