Locations Main Campus: Chesterfield, MO 63017   |   Locations
314-434-1500 314-434-1500   |   Contact Us

Multimedia Encyclopedia


 
E-mail Form
Email Results

 
 
Print-Friendly
Bookmarks
bookmarks-menu

Neonatal hypothyroidism

Cretinism; Congenital hypothyroidism

 

Neonatal hypothyroidism is decreased thyroid hormone production in a newborn. In very rare cases, no thyroid hormone is produced. The condition is also called congenital hypothyroidism. Congenital means present from birth.

Causes

 

Hypothyroidism in the newborn may be caused by:

  • A missing or poorly developed thyroid gland
  • A pituitary gland that does not stimulate the thyroid gland
  • Thyroid hormones that are poorly formed or do not work
  • Medicines the mother took during pregnancy
  • Lack of iodine in the mother's diet during pregnancy
  • Antibodies made by the mother's body that block the baby's thyroid function

A thyroid gland that is not fully developed is the most common defect. Girls are affected twice as often as boys.

 

Symptoms

 

Most affected infants have few or no symptoms. This is because their thyroid hormone level is only slightly low. Infants with severe hypothyroidism often have a unique appearance, including:

  • Dull look
  • Puffy face
  • Thick tongue that sticks out

This appearance usually develops as the disease gets worse.

The child may also have:

  • Choking episodes
  • Constipation
  • Dry, brittle hair
  • Jaundice
  • Lack of muscle tone ( floppy infant)
  • Low hairline
  • Poor feeding
  • Short height
  • Sleepiness
  • Sluggishness

 

Exams and Tests

 

A physical exam may show:

  • Decreased muscle tone
  • Slow growth
  • Hoarse-sounding cry or voice
  • Short arms and legs
  • Very large soft spots on the skull (fontanelles)
  • Wide hands with short fingers
  • Widely separated skull bones

Blood tests are done to check thyroid function. Other tests may include:

  • Thyroid ultrasound scan
  • X-ray of the long bones

 

Treatment

 

Early diagnosis is very important. Most of the effects of hypothyroidism are easy to reverse. For this reason, most US states require that all newborns be screened for hypothyroidism.

Thyroxine is usually given to treat hypothyroidism. Once the child starts taking this medicine, blood tests are regularly done to make sure thyroid hormone levels are in a normal range.

 

Outlook (Prognosis)

 

Getting diagnosed early usually leads to a good outcome. Newborns diagnosed and treated in the first month or so usually have normal intelligence.

Untreated mild hypothyroidism can lead to severe intellectual disability and growth problems. The nervous system goes through important development during the first few months after birth. Lack of thyroid hormones can cause damage that cannot be reversed.

 

When to Contact a Medical Professional

 

Call your health care provider if:

  • You feel your infant shows signs or symptoms of hypothyroidism
  • You are pregnant and have been exposed to antithyroid drugs or procedures

 

Prevention

 

If a pregnant woman takes radioactive iodine for thyroid cancer, the thyroid gland may be destroyed in the developing fetus. Infants whose mothers have taken such medicines should be observed carefully after birth for signs of hypothyroidism. Also, pregnant women should not avoid iodine-supplemented salt.

Most states require a routine screening test to check all newborns for hypothyroidism. If your state does not have this requirement, ask your provider if your newborn should be screened.

 

 

References

LeFranchi SH, Huang SA. Hypothyroidism. In: Kliegman RM, Stanton BF, St. Geme, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 565.

Van Vliet G, Deladoëy J. Disorder of the thyroid in the newborn and infant. In: Sperling MA, ed. Pediatric Endocrinology . 4th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 7.

 

        A Closer Look

         

          Talking to your MD

           

            Self Care

             

              Tests for Neonatal hypothyroidism

               

               

              Review Date: 4/27/2015

              Reviewed By: Kimberly G Lee, MD, MSc, IBCLC, Associate Professor of Pediatrics, Division of Neonatology, Medical University of South Carolina, Charleston, SC. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

              The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

               
               
               

               

               

              A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.



              Content is best viewed in IE9 or above, Firefox and Google Chrome browser.