| Abstrakt: |
Subacute thyroiditis in an ectopic thyroid gland has not been reported. Our patient presented at age 4 10/12 with a mass in the left upper anterior neck. Scan 2 years previously when euthyroid revealed uptake only in the mass. On our evaluation she was euthyroid with enlargement of the mass, measuring 3.5 × 2 cm. RIA T4 and T3 were 8.1 ng (NL 5.1 - 11.5) and 191 ng/100 ml (NL adult 60 - 160)respectively. TSH was < 2.5 μU/ml with no increase following TRH. 2 wks later 24 hr RAI was 1.2%. TBG was 20 μg T4/100 ml (NL 16 - 24). The data were compatible with subacute thyroiditis so no therapy was given. Over the next 4 mos RIA T4 and T3 decreased to 0.8 μg/100 ml and 85 ng/100 ml respectively and TSH rose to > 60 μU/ml. During subsequent 4 mos of replacement therapy, the mass was not palpable. During 3 mos following stopping replacement therapy, sequential T3 72, 97, 115; and T4 1.8, 4.2, 6.8 increased. TSH decreased 120, 56, 42. 24 RAI uptake was 28% (slightly elevated). We conclude that pathological release of thyroid hormones occurring in subacute thyroiditis suppresses TRH-induced TSH release during initial phase of SAT. During recovery, the elevated RAI uptake is accompanied by high TSH levels which decrease as T3 and T4 return to normal. |
