Hyperthyroidism, also called thyrotoxicosis, is an overactive thyroid gland which causes an overactive metabolism. While rare, hyperthyroidism in children and adolescents is manageable. Neonatal Graves disease---hyperthyroidism in newborns---can be life-threatening.
The thyroid gland, shaped like a butterfly and part of the endocrine system, is located at the front of the neck. It controls the body's metabolism, regulating mood, weight, and mental and physical energy levels. Disorders of the thyroid are treated by endocrinologists.
Causes in Infants
An infant with hyperthyroidism---called neonatal Graves disease---contracts it from his or her mother in utero; in adults, Graves disease an autoimmune disease which produces antibodies that stimulate the thyroid gland. Children's Hospital in Boston explains in a posting on its website that a pregnant woman possessing these antibodies from a current or previous bout of Graves disease can pass them to the foetus. If the fetus's thyroid gland is affected, it can lead to miscarriage, stillbirth or premature birth. Additionally, for those infants who survive, there are medical complications which can follow them through life.
Symptoms & Treatments
According to Children's Hospital, symptoms of neonatal Graves disease include poor weight gain, a rapid heartbeat, high blood pressure, bulging eyes, diarrhoea, vomiting, and difficulty breathing. Newborns who don't get correctly diagnosed---by a blood test---and receive immediate treatment risk complications including the premature closing of bones in the skull, mental retardation and delayed growth.
Infants diagnosed with hyperthyroidism are treated with medication which blocks the production of thyroid hormones. According to Children's Hospital, they usually recover fully within a few weeks; however, doctors will monitor them carefully throughout their first year of life to make sure the hyperthyroidism doesn't return.
Hyperthyroidism in Older Children and Adolescents
Research into hyperthyroidism in children shows that it is almost always the result of Graves disease, though this disorder mostly affects women over the age of 20.
Symptoms & Treatments
Early symptoms of Graves disease in children are typically vague, and include restlessness--often leading to disruptive behaviour in school--and sleep disturbances.
When the child's hyperthyroidism becomes more severe, symptoms similar to those exhibited by adult sufferers begin to emerge, including an enlarged thyroid gland, quickened pulse, anxiousness, heat intolerance, weight loss, shaking hands, muscle weakness, sleep disturbances, and diarrhoea. Additionally, children and adolescents may experience rapid growth.
Hyperthyroidism in children is first treated with antithyroid medications to limit the activity of the thyroid. Additionally, according to U.S. National Library of Medicine and the National Institutes of Health, beta blockers such as propranolol might be prescribed to treat rapid heart rate, sweating, and anxiety until the hyperthyroidism is controlled. A February 2008 issue of Pediatrics, the official journal of The American Academy of Pediatrics, reports that a majority of children eventually will require additional treatment---radioactive iodine or surgery. These can lead to hypothyroidism, or an underactive thyroid, which can be treated throughout a child's life with medications.
According to the Mount Nittany Medical Center in State College, Pennsylvania, children and adolescents diagnosed with hyperthyroidism will require regular check-ups with their endocrinologists, and might have to be monitored for the rest of their lives.