Patients with Hashimoto's disease treated with L-thyroxine and followed for three years

Tireoidite de Hashimoto na Infância e na Adolescência: Estudo Retrospectivo de 43 Casos

A tireoidite de Hashimoto (TH) é uma doença auto-imune considerada a principal causa de bócio e hipotireoidismo adquirido em crianças e adolescentes em áreas não endêmicas. Este estudo avaliou retrospectivamente 43 pacientes entre 1,1 e 17,6 anos com TH, 36 do sexo feminino e 7 do sexo masculino (proporção 5:1). Destes, 81% apresentavam bócio. Na avaliação inicial 37% dos pacientes eram eutireóideos (n=16), 28% apresentavam hipotireoidismo compensado (n=12), 26% hipotireoidismo descompensado (n=11) e 9% eram hipertireóideos (n=4). Anticorpo anti-tireoperoxidase esteve positivo em 75% dos casos e anti-tireoglobulina em 68%. Todos os pacientes com hipotireoidismo foram tratados com reposição de tiroxina. Apenas 3 pacientes entraram em remissão após o término da puberdade sugerindo que a evolução para remissão deve ser considerada e avaliada também após esta fase e periodicamente.

[Chronic autoimmune thyroiditis in the child]

OBJECTIVE

The aim of the study was to describe the clinical characteristics and long-term follow-up of a group of children with chronic autoimmune thyroiditis.

PATIENTS AND METHODS

Sixty children (age: 11.9 +/- 2.7 years) were studied in a retrospective analysis.

RESULTS

At diagnosis, 34 of the children were hypothyroid (compensated hypothyroidism, n = 15; true hypothyroidism, n = 19) and 26 euthyroid. Thyroid ultrasonography showed characteristic features of heterogenicity and/or hypoechogenicity in all patients. Other autoimmune diseases were found in ten subjects (17%) and 23% had a family history of thyroid disease. At the end of the follow-up, nine of 45 children (20% of the cases) followed up for at least one year (mean follow-up 4.4 +/- 3.7 years), demonstrated a change in thyroid function. Hypothyroidism was detected in two initially euthyroid patients. Among initially hypothyroid patients, seven (28%) recovered normal thyroid function, allowing L-thyroxine withdrawal for four weeks, after 1.5 to 8.4 years. No factor was found to be predictive of the course of the disease. All subjects treated with L-thyroxine for hypothyroidism reached normal final height.

CONCLUSION

The natural course of chronic lymphocytic thyroiditis is variable and unpredictable. Recovery from hypothyroidism does occur and can be aided by the L-thyroxine withdrawal test. The disease requires lifelong thyroid surveillance, especially in women during pregnancy, in order to avoid a potential adverse effect on the future child.