MC preventable cause of Mental retardation

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Most Common Preventable cause of Mental retardation is Hypothyroidism.

Clinical scenario : Child with Hypotonia , Umblical hernia and prolonged physical Jaundice

Sutures - Widely open
Posterior fontanel - Open in hypothyroidism

Important point : TSH in child should be done >48hrs - 6days.
Reason -
If maternal TSH is high then we get false positive high TSH in Cord blood as well as on day 1.
i.e 24-48hrs in the child - Normally there would be High TSH.

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