Congenital Hypothyroidism Clinical Presentation

Updated: Oct 14, 2017
  • Author: Maala S Daniel, MBBS; Chief Editor: Sasigarn A Bowden, MD  more...
  • Print
Presentation

History

In regions of iodide deficiency and a known prevalence of endemic cretinism, the diagnosis may be straightforward.

Infants with congenital hypothyroidism are usually born at term or after term.

Symptoms and signs include the following:

  • Decreased activity

  • Large anterior fontanelle

  • Poor feeding and weight gain

  • Small stature or poor growth

  • Decreased stooling or constipation

  • Hypotonia

  • Hoarse cry

Often, they are described as "good babies" because they rarely cry and sleep most of the time.

Family history should be carefully reviewed for information about similarly affected infants or family members with unexplained mental retardation.

Maternal history of a thyroid disorder and mode of treatment, whether before or during pregnancy, can occasionally provide the etiology of the infant's problem.

Congenital hypothyroidism is more common in infants with birthweights less than 2,000 g or more than 4,500 g. [27, 44]

Congenital hypothyroidism is more common in multiple births, with a low concordance rate. [29]

Next:

Physical

The physical findings of hypothyroidism may or may not be present at birth (see the image below).

An infant with cretinism. Note the hypotonic postu An infant with cretinism. Note the hypotonic posture, coarse facial features, and umbilical hernia.

Signs include the following:

  • Coarse facial features

  • Macroglossia (See the image below.)

    Note the macroglossia. Note the macroglossia.
  • Large fontanelles

  • Umbilical hernia

  • Mottled, cool, and dry skin

  • Developmental delay

  • Pallor

  • Myxedema

A small but significant number (3-7%) of infants with congenital hypothyroidism have other birth defects, mainly atrial and ventricular septal defects. [11]

Newborn screening involves the following:

  • Infants with congenital hypothyroidism are usually identified within the first 2-3 weeks of life.

  • These infants should be carefully examined for signs of hypothyroidism, and the diagnosis should be confirmed by repeat testing.

  • Infants with obvious findings of hypothyroidism (eg, macroglossia, enlarged fontanelle, hypotonia) at the time of diagnosis have intelligence quotients (IQs) 10-20 points lower than infants without such findings.

Anemia may occur, due to decreased oxygen carrying requirement.

Previous