Ocular manifestations in children and adolescents with thyrotoxicosis

Thyrotoxicosis is a rare disorder in childhood and adolescence. The frequency ranges from 0.1 in 100000 in young children to 3.0 in 100000 in adolescents and the most frequent cause is Graves' disease. Few children and adolescents suffer from thyrotoxicosis during the course of autoimmune thyroiditis and non-autoimmune hyperthyroidism due to constitutively active mutations of the TSH-receptor have been reported in single patients with neonatal hyperthyroidism and rare familial cases. From a survey of the literature it is apparent that infiltrative ophthalmopathy is very rare in children and adolescents. Milder ocular manifestations as retraction of the upper eyelid, upper lid lag and "staring eyes" are reported in varying frequencies ranging from 25 to 60% of all patients. In our own series of 43 children and adolescents (34 females, 9 males) with thyrotoxicosis only 16 (37%) had clear ocular manifestations of upper lid retraction, lid lag and slight protrusio bulbi. However, only three of of them had soft tissue involvement and significant exophtalmus. In none of the patient corneal or optic nerve involvement or paralysis of the extraorbital muscles was observed. Newborns with congenital hyperthyroidism due to maternal Graves' disease seem to present significant transitory ocular manifestations more frequently, but again no infiltrative ophtalmopathy requiring specific therapy is present. Recently at least four different newborns with congenital thyrotoxicosis due to gain-of-function mutations of the TSH-receptor have been reported, who also had significant ocular manifestations. The presence of staring eyes, slight proptosis and lid retraction in these newborns without any autoimmune or inflammatory process supports the hypothesis that these ocular manifestations are caused by the increased thyroid hormone actions. The involvement of the eyes is usually transitory in newborns as well as in children and adolescents and the symptoms usually disappear when euthyroidism is restored. The administration of steroids therefore is restricted to the rare severe cases with eye muscle or soft tissue involvement. There are no reports on surgical decompression or orbital irradiation therapy of ophtalmopathy in children and adolescents, which again indicates that ocular involvement in thyrotoxicosis in children and adolescents is less frequent and much less severe than in adults.