Pediatric Graves Disease Clinical Presentation

Children with Graves disease are usually initially identified because of an enlarged thyroid, weight loss, or behavioral changes. Exophthalmos, which is common in adults with Graves disease, is less common in children. The reason for this difference is not clear; however, smoking is a well-recognized risk factor for exophthalmos.

The enlarged thyroid may be big enough to cause dysphagia, with reports of difficulty swallowing. Usually, the enlarged thyroid is identified by a parent or physician and is not overtly symptomatic. Weight loss accompanied by a voracious appetite and excessive growth in height can lead to initial evaluation. Often, children begin to have distractibility in the classroom, trouble sleeping, and mood changes, resulting in the identification of thyroid enlargement and elevated levels of circulating thyroid hormone.

The astute clinician may identify these children when they are referred for evaluation of symptoms of attention deficit disorder (ADD). Adolescents with this disorder may also report pruritus, temporal hair loss, thinning of the hair, darkening of the skin, palpitations, and, in girls, amenorrhea or infrequent or light menses. Frequent stools or frank diarrhea and symptoms of heat intolerance are common. A strong family history of Graves disease or other autoimmune thyroid disease may be noted.

Symptoms include the following:

• Dysphagia
• Irritability and emotional lability
• Sleeplessness and restlessness
• Inability to concentrate
• Deterioration of handwriting and school performance
• Frequent stools or diarrhea
• Palpitations
• Pruritus
• Weight loss
• Increased appetite
• Nocturia, increase in urination, and thirst
• Infrequent or light menses
• Weakness and tiredness
• Exercise intolerance
• Heat intolerance

Upon initial inspection, children and adolescents with thyrotoxicosis are usually tall and thin, with a fixed staring gaze and fidgety behavior. Children with thyrotoxicosis may sit on their hands or clasp their hands to control fidgeting. A widened pulse pressure and a rapid heart rate are typically found.

Ocular findings

Ocular findings are often independent of the degree of thyrotoxicosis and may appear before the onset of hyperthyroidism.^{[4, 5, 6, 7]}

Exophthalmos may be present and is usually mild. Weakness of the extraocular muscles is rare, but may be elicited by checking the capacity for convergence and looking for lid lag. Some adolescents may have true inability to close the eyelids because of more severe exophthalmos. Severe exophthalmos can be associated with a sandy, gritty feeling in the eyes upon awakening or with corneal irritation or ulceration (exceedingly rare). Exophthalmos may be unilateral.

Nonspecific signs include lid reaction, wide palpebral aperture (ie, Dalrymple sign, confirmed when the sclera is visible above the superior limbal margin), lid lag (von Graefe sign), stare or appearance of fright, infrequent blinking (Stellwag sign), and absent wrinkling of forehead skin on upward gaze (Joffroy sign). Signs unique to orbitopathy in Graves disease include the following:

• Upper eyelid retraction (the most common sign of Graves ophthalmopathy)
• Infrequent or incomplete blinking (Stellwag sign)
• Lid lag upon infraduction (Von Graefesign) or globe lag on supraduction (Kocher sign)
• Widened palpebral fissure during fixation (Dalrymple sign)
• Incapacity to close eyelids completely (lagophthalmos)
• Prominent stare (Binswanger sign)
• Inability to keep the eyeballs converged (Mobius sign)
• Limited extraocular gaze (especially upward)
• Diplopia
• Blurred vision due to inadequate convergence and accommodation
• Swollen orbital contents and puffy lids
• Chemosis
• Irritated eye
• Globe pain
• Exophthalmos
• Enlarged lacrimal glands (visible on inspection and palpable)
• Visible swelling of lateral rectus muscles at insertion sites into the globe and injection of overlying vessels
• Dysfunctional lacrimal glands with decreased quantity and abnormal composition of tears
• Corneal injection, ulceration, punctate epithelial erosions, or superior limbic keratoconjunctivitis (rare)
• Decreased visual acuity due to papilledema, retinal edema, retinal hemorrhages, or optic nerve damage (rare)

Always perform thyroid function tests (TFTs) in addition to local imaging studies in children with unilateral exophthalmos or proptosis to rule out orbital tumor.

Exophthalmos can be quantitated using an exophthalmometer, which measures the extension of the eye beyond the bony socket. This measurement is standardized for adults. Values for young children are not readily available, but these findings may still be useful to measure progression of the eye disease.

Thyroidal findings

The thyroid is firm and usually smooth and rubbery. A bosselated gland may suggest the thyrotoxic phase of chronic lymphocytic thyroiditis.

A gland with a single nodule suggests an autonomously functioning nodule inducing thyrotoxicosis, whereas a multinodular gland indicates a multinodular goiter, a reasonably rare finding in children living in an iodine-replete environment. Malignancy is rarely associated with such hyperfunctioning lesions.

The finding of hyperthyroidism without a goiter suggests the possibility of exogenous administration of thyroid hormone.

Cardiopulmonary manifestations

Cardiac examination may reveal the murmur of mitral valve prolapse. A rapid heart rate and prominent precordium are noted. Atrial fibrillation may rarely be induced by thyrotoxicosis in children. In the most severe form of thyrotoxicosis associated with Graves disease, thyroid storm, high-output heart failure is observed.

Neuromuscular findings

Deep tendon reflexes are exaggerated. Thenar and hypothenar wasting may be noted. Muscle weakness can be profound.

In some genetically prone individuals, periodic paralysis associated with hypokalemia may be induced by thyrotoxicosis. Although thyrotoxic periodic paralysis is described as an adult disorder, it has been observed in adolescents.

Dermal manifestations

The skin is usually fine and moist. Excoriations may be present because of pruritus. Skin darkening may be observed in some darker-skinned individuals. Thyrotoxicosis may intensify the lesions of acanthosis nigricans. The presence of irregular café au lait spots may suggest the diagnosis of thyrotoxicosis associated with McCune-Albright syndrome rather than Graves disease.