Aim: To investigate hashitoxicosis outcome in 14 children with persistent absence of thyrotropin receptor autoantibodies who were followed for 1.3-8.8 years (mean 3.5 ± 2.5). Due to a more severe presentation, 4 patients required methimazole (subgroup A1), whilst in the remaining 10 cas es (subgroup A2) no treatment was given. Results: A definitive resolution of hyperthyroidism was recorded 8.3 ± 6.3 months after diagnosis, even though there was a wide variability between subjects (3-23 months). In subgroup A2, hyperthyroidism resolution occurred spontaneously and earlier with respect to subgroup A1 (4.8 ± 2.0 months after diagnosis vs. 17.0 ± 4.5, p = 0.00001). After hyperthyroidism resolution, no relapses were recorded in any patients. Hyperthyroidism duration positively correlated with thyroid peroxidase autoantibody (TPOAb) levels at presentation (r = 0.729, p = 0.002). Conclusions: In all the 14 hashitoxicosis children with persistently absent thyrotropin receptor autoantibodies, the hyperthyroid phase was widely variable and always followed by definitive resolution with no relapses and persistent euthyroidism or hypothyroidism. In the few patients with a more severe presentation, methimazole treatment was required, and definitive hyperthyroidism resolution was delayed. In this subgroup, TPOAb levels at diagnosis were higher than in the subgroup with less severe presentation and earlier hyperthyroidism resolution, suggesting a relationship between TPOAb levels and severity of the disease.

Keywords:
Graves' disease, Hashimoto's thyroiditis, Hashitoxicosis
1.
Fatourechi V, McConahey WM, Woolner LB: Hyperthyroidism associated with histologic Hashimoto's disease. Mayo Clin Proc 1971;46:682-689.
2.
Rallison M, Dobyns BM, Keating FR, Rall JE, Tyler FH: Occurrence and natural history of chronic lymphocytic thyroiditis in childhood. J Pediatr 1975;86:675-682.
3.
Williamson S, Greene SA: Incidence of thyrotoxicosis in childhood: a national population based study in the UK and Ireland. Clin Endocrinol 2010;72:358-363.
4.
Nabhan ZM, Kreher NC, Eugster EA: Hashitoxicosis in children: clinical features and natural history. J Pediatr 2005;146:533-536.
5.
Reinwein D, Benker G, Konig MP, Pinchera A, Schatz H, Schleusener A: The different types of hyperthyroidism in Europe. Results of a prospective survey of 924 patients. J Endocrinol Invest 1988;11:193-200.
6.
De Luca F, Corrias A, Salerno M, Wasniew-ska M, Gastaldi R, Cassio A, Mussa A, Aversa T, Radetti G, Arrigo T: Peculiarities of Graves' disease in children and adolescents with Down's syndrome. Eur J Endocrinol 2010;162:591-595.
7.
Chung YJ, Lee BW, Kim JY, Jung JH, Min YK, Lee MS, Lee MK, Kim KW, Chung JH: Continued suppression of serum TSH level may be attributed to TSH receptor antibody activity as well as the severity of thyrotoxicosis and the time to recovery of thyroid hormone in treated euthyroid Graves' patients. Thyroid 2006;12:1251-1257.
8.
Laurberg P, Wallin G, Tallsted L, Abraham-Nordling M, Lundell G, Torring O: TSH-receptor autoimmunity in Graves' disease after therapy with anti-thyroid drugs, surgery, or radioiodine: a 5-year prospective randomized study. Eur J Endocrinol 2008;158:69-75.
9.
Cronin CC, Higgins TM, Murphy D, Ferriss JB: Concomitant Graves' disease and Hashimoto's thyroiditis, presenting as primary hypothyroidism. Ir Med J 1996;89:141-142.
10.
Abraham P, Avenell A, Park CM, Watson WA, Bevan JS: A systemic review of drug therapy for Graves' hyperthyroidism. Eur J Endocrinol 2005;153:489-498.
11.
Elbers L, Mourits M, Wiersinga W: Outcome of very long-term treatment with antithyroid drugs in Graves' hyperthyroidism associated with Graves' orbitopathy. Thyroid 2011;21:279-283.
© 2012 S. Karger AG, Basel
2012
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