The article is intended to be a one-stop evidence-based review of pediatric thyroid diseases commonly seen in primary care. It covers hypothyroidism, hyperthyroidism, thyroid nodules, and thyroid cancer and provides tools for evaluating these disorders.
"The primary care physician plays a critical role in identifying children and adolescents with thyroid disease," lead author Andrew Bauer, MD, from Children's Hospital of Philadelphia, Pennsylvania, commented to Medscape Medical News.
Dr Bauer formerly practiced general pediatrics before completing an endocrinology fellowship and said he was sensitive to the demands and time pressures of frontline healthcare providers.
He emphasized the importance of early identification and treatment of thyroid disorders, which can affect growth and neurocognitive development.
"An understanding of the risk factors, signs and symptoms, as well as the evaluation and treatment of hypothyroidism and hyperthyroidism, is associated with earlier diagnosis, earlier initiation of treatment, and reduced morbidity from disease," he stressed.
The authors included information from 83 articles identified through a literature search and published between January 2010 and December 2015, along with some earlier articles of historical interest.
It covers basic pathophysiology, clinical presentation, diagnosis (including laboratory and radiologic assessment), and treatment of congenital hypothyroidism, acquired hypothyroidism, hyperthyroidism, and thyroid nodules. The article also lists criteria for selecting which patients should have definitive treatment for Graves disease.
The review points out a key feature in differentiating hypo- and hyperthyroidism from thyroid nodules: The former are often symptomatic at presentation, while the latter often do not have symptoms and are diagnosed incidentally on physical exam.
"Signs and symptoms of acquired thyroid disease include altered growth, goiter, and/or change in behavior or school performance. Patients with thyroid nodules and thyroid cancer are typically asymptomatic at the time of diagnosis," Dr Bauer explained.
Acquired hypothyroidism is most commonly due to an autoimmune disorder (Hashimoto thyroiditis), with a 1% to 2% prevalence in childhood and a 4:1 female-to-male ratio.
Congenital hypothyroidism affects about 1:1500 to 1:3000 infants diagnosed through universal screening as part of the newborn exam. Affected infants are often asymptomatic at birth but may develop symptoms after the first 48 hours of life.
Meanwhile, hyperthyroidism accounts for about 15% of pediatric thyroid disorders, mostly due to autoimmune hyperthyroidism (Graves disease). Hyperthyroidism has a peak incidence at ages 10 to 15 years.
The incidence of thyroid nodules has increased over the past few decades. Most nodules are benign, but those diagnosed before age 19 years have a higher rate of malignancy than those in older patients.
Because children and teens often have enlarged lymph nodes, a working knowledge of the common location of reactive compared with pathologic lymph nodes is important, according to Dr Bauer. Papillary thyroid cancer, the most common form of thyroid cancer, commonly metastasizes to the cervical and lateral neck lymph nodes. Therefore, the authors provide a diagram showing the location of lymph nodes in the neck and which ones to suspect in thyroid cancer.
Dr Bauer also emphasized the importance of a complete thyroid and lymph node exam, which can be conducted in 1 to 2 minutes as part of a well-care visit. He and his coauthors have developed a YouTube video on how to perform a complete thyroid exam in different types of patients, including those with a normal thyroid.
"For patients with persistent lymphadenopathy, thyroid cancer must be included in the differential diagnosis. If a malignancy is being considered, a thyroid and neck ultrasound should be performed prior to referral for diagnostic, excisional lymph node biopsy," he explained.
When possible, patients should be referred to a pediatric thyroid center experienced in pediatric thyroid nodules and cancer, Dr Bauer added.
Because most patients will need long-term or lifelong medical therapy and follow-up, the authors stressed the importance of communication between primary care providers and subspecialists.
