CHRONIC LYMPHOCYTIC THYROIDITIS (CLT) IN THYEOXINE (T4) TREATED CHILDREN

Progression of CLT in T4 treated children has been poorly documented. The response of endogenous T4, T3 and TSH to withdrawal after 2 to 9 yrs of therapy in 6 children, 7-18 yrs, was studied with weekly levels for 4-20 wks. At Dx. of CLT 5 had hypothyroid values. Results indicated 3 patterns of response: 1) clinical and lab evidence of hypothyroidism in 6 wks, 2) increased TSH with normal T4 followed by return of goiter 8 wks off therapy, 3) clinical & chemical euthyroidism in 3 with no return of goiter 12-20 wks off therapy. This group demonstrated a reduction in agglutinating antibody (Ab) titers from initial levels. Two had hypothyroid lab data at dx. of CLT. Normal TSH, T4 & T3 occurred 3 wks after discontinuing therapy. A reduction in Ab titers with normal TSH accompanied euthyroidism. Hypothyroidism coincided with unchanged Ab. In contrast to adults treated for 10 yrs, with deterioration in thyroid function noted 6 wks off therapy (Papapetrou et al, Lancet, Nov.72), these studies indicated that the child may recover function after a period of replacement.