Thyroiditis in Children
Laura K. Bachrach MD1
Thomas P. Foley Jr MD2
1 Assistant Professor of Pediatrics, Stanford University School of Medicine, Stanford, California
2 Professor of Pediatrics, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania
Thyroiditis ranks with diabetes as the most common of the endocrine disorders of childhood. The term encompasses all forms of thyroid gland inflammation and infection, although chronic lymphocytic thynoiditis is overwhelmingly the most frequent. Thyroiditis may appear as a mass in the neck of an asymptomatic child or it may be a painful, erythematous goiter in a sick child. The affected thyroid gland may be small on large, with varying degrees of dysfunction. Most commonly, thyroiditis causes euthyroid function, although the disease process can result in transient or permanent thyroid dysfunction. The causes of thyroiditis in childhood, as well as the less common thyroid disorders in the differential diagnosis of goiter, are listed in Table 1. Thyroid physiology and pathophysiology will be discussed briefly to explain the rationale for diagnostic studies and treatment strategies. The more recent diagnostic techniques and therapeutic controversies regarding thyroiditis will be included. The goal is to provide the clinician with renewed awareness of this most common pediatric problem.
THYROID PHYSIOLOGY
Thyroid hormone production is regulated by a classical negative feedback system (Fig 1). Hypothalamic thyrotropin-releasing hormone (TRH) stimulates the synthesis and secretion of thyroid-stimulating hormone (TSH) from the pituitary. TSH, in turn, stimulates production and release of thyroxine (T4) and triiodothyronine (T3).
