ESPE Abstracts

Introduction: Beta thalassemia is a common genetic disorder in Mediterranean countries. Congenital hypothyroidism is also a condition resulting with deficiency of thyroid hormone in newborn infants. Autoimmune thyroid dysfunction in childhood patients with thalassemia major is uncommon and poorly described. We report a case of a child with two independent diseases - clinical hypothyroidism diagnosed in early childhood, and beta thalassemia major who developed autoimmune thyroiditis with unusual acute thyroid dysfunction.

Case presentation: We present a 13-year-old boy with beta thalassemia major and clinical hypothyroidism diagnosed in infantile period. The child received regular L-thyroxine therapy and multiple transfusions together with chelation therapy. Haploidentical transplantation of hematopoietic stem cells from his mother was performed two years ago. Since then, patient was put on immunosuppressive therapy. In January 2019, he represents with anterior neck pain and fever. Clinical exam showed periorbital swelling. Laboratory evaluation of the thyroid function revealed increased FT4 levels (>77.2 pmol/L) and decreased TSH levels (0.029ulU/ml), explaining the thyrotoxic crisis with hormonal discharge. Thyroglobulin antibodies were extremely elevated (2168 IU/ml). The pneumoslide was positive for Adenovirus IgG. Acute autoimmune thyroiditis due to the viral infection in immunocompromised child was diagnosed. The thyroxine replacement therapy was temporarily stopped, after several weeks the therapy was given gradually until TSH level become normal.

Conclusion: Although the simultaneous occurrence of beta thalassemia major, acute and autoimmune thyroiditis in patient on thyroxine replacement therapy can be coincidental, this combination is rare in childhood. To the best of our knowledge, there is no evidence about a plausible association between the acute autoimmune thyroiditis and immunosuppressive therapy given after transplantation. This type of thyroiditis can be overlooked and early diagnosis is important to correct the negative systemic effect of thyroid dysfunction. Follow up of thyroid function in transplanted children that have received immunosuppressive therapy is mandatory.