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What is cretinism ?

Cretinism is a condition produced due to hypothyroidism since birth due to partial or complete failure of thyroid gland  (commonly it is due to thyroidal agensis).
Juvenile myxoedema is a condition with onset of hypothyroidism since childhood but develops before puberty ,this is only due to dyshormonogenesis
Myxoedema is characteried by onset of hypothyroidism after puberty (probably Hashimolo's thyroiditis is the commonest cause of myxoedema).
What are the morphologic characteristics of cretin?
 The facies in cretinism 
  • Appearance is dull and idiotic.
  • There is depressed bridge of the nose, broad flat nose with big nostrils.
  • Hypertelorism (widely set eyes) with wrinkling of eyebrows : narrow palpebral fissures.
  • Cretin has Sparse hair with dry skin.
  • Their lips are thick and everted with big, protruded tongue (macroglossia)
  • There is Delayed dentition.
The other features are
  • Short stature but they maintains the infantile proportion, ie. upper segment > lower segment.
  • These patients are lethargic and apathetic.
  • Memory is grossly impaired. Markedly retarded intelligence
  • Skin is dry. rough  and cold with sparse scalp hair.
  • Thick and short neck with presence of supraclavicular pad ot fat.
  • Pot-bellied abdomen with umbilical hernia is observed
Clinical features of hypothyroidism in neonatal period
Hypothyroididm in the neonatal period may be associated with the following
  • Prolonged physiological jaundice.
  • Somnolence.
  • Feeding problem (difficulty in sucking)
  • Constipation
  • Hoarse cry 
  • Delayed milestones of development (is observed in  later months)
How will you diagnose cretinism based on laboratory tests?
Blood investigations
  • High serum cholesterol.
  • Low protein bound iodine
  • Low radioactive I131 uptake.
  • T3 and T4 levels are low with high TSH level.
ECG - Low voltage complex is seen.
Skeletal x-ray (of long bones and pelvis) 
In cretinism there is delayed closure of epiphysis (i.e. bone age is less than that of chronological age).
Epiphyseal dysgenesis - Instead of one epiphysis, there are multiple epiphysis (This is DIAGNOSTIC of cretinism).
How will you treat Cretin?
  • Very small dosage of L-thyroxine is needed. Initial dose is 10 to 25 microgram and the dose is adjusted according to clinical improvement as well as the biochemical findings.
  • Rehabilitation.