Question

Features of hypothyroidism in infancy include the following except:

• A. Premature closure of posterior fontanelle
• B. Coarse facies
• C. Umbilical hernia
• D. Constipation

Hint:

Hypothyroidism delays bone maturation, so fontanelles do the opposite of closing early.

Answer 1

The Correct Option is A

Step 1: In a baby with an underactive thyroid, everything runs slow, including skeletal development. A delayed bone age means the cranial sutures and fontanelles stay open longer than expected.

Step 2: The reduced metabolic drive produces the typical picture of coarse features, an umbilical hernia from a lax abdominal wall, and stubborn constipation due to slow gut motility. All of these are true findings.

Step 3: Since the posterior fontanelle actually shows late closure rather than early closure, the statement about premature closure is false and is the answer to this except-type question.

\[\boxed{\text{Premature closure of posterior fontanelle}}\]