Clinical, biochemical and cytomorphological observations in juvenile chronic lymphocytic thyroiditis.

OBJECTIVE: To determine the clinical, biochemical, ultrasonological and cytomorphological features in goitrous juvenile chronic lymphocytic thyroiditis(CLT). SETTING: Tertiary referral center for thyroid disorders. SUBJECTS: A total of 455 children were evaluated for goiter. Of these 122 children had features of CLT in FNAC and were further studied. METHODS: All subjects were subjected to detailed clinical examination. The thyroid functional status was assessed by estimation of serum concentration of thyroid hormones (thyroxine and triiodothyronine) and thyrotropin (TSH). In addition the antithyroid antibody titers were measured. Ultrasonological and cytomorphological characteristics in these patients were also evaluated. RESULTS: The mean age at presentation was 12.5 years (SD 3.93). The male: female ratio was 1:7.7. Thyroid functional status as assessed by serum thyroxine and thyrotropin levels revealed, euthyroidism in 67 (54.9%), hypothyroidism in 30 (24.6%), subclinical hypothyroidism in 22 (18%) and hyperthyroidism in 3 (2.5%). Thyroid antimicrosomal antibodies were detected in significant titers in 90 (73.8%) and antithyroglobulin was positive in 71 (58.2%). The positivity of the antimicrosomal and antithyroglobulin antibodies were much higher in subjects with hypothyroidism and was detected in 86.5% and 69.2%, respectively. The mean urinary iodine excretion was 74.1 micrograms/g of creatinine (SD 31.4) indicating mild iodine deficiency. Fine needle aspiration cytoloty (FNAC) revealed features of chronic lymphocytic thyroiditis. Hurthle cell changes was seen in only 12% of the cases. The epithelium was more often hyperplastic and vacuolation of the cytoplasm and peripheral vacuolations were seen frequently. Giant cells and epithelioid cells were seen in many cases. CONCLUSIONS: In any child presenting with firm goiter, a diagnosis of CLT should be excluded. Many subjects with juvenile CLT have biochemical evidence of hypothyroidism but only few symptoms or clinical features.

Prognostic significance of thyroid antibodies in hyperthyroid patients treated with antithyroid drugs.

Lymphocytic infiltration of the thyroid gland in patients with hyperthyroidism is associated with the presence of serum antithyroidal microsomal antibodies (TMA) and serum antithyroglobulin antibodies (TGA). The aim of this study was to evaluate the clinical significance of TMA and TGA during and after treatment of hyperthyroidism with antithyroidal drugs. One hundred and fifty-four hyperthyroid patients were treated for 18 months with methimazole and then followed up for 18 months or more (mean, 24.8 +/- 12.6 months). Patients were classified into three group. group I, patients negative for TGA and TMA before and during 18 months of treatment, group II patients positive for TMA but negative for TGA before and during 18 months treatment and group III patients who were positive for both TGA and TMA before and during treatment. The relapse rates after discontinuation of treatment in these group were 44.7% (17 of 38), 29% (18 of 62) and 11.1% (6 of 54), respectively. The value in group I was significantly higher than that in group III (P < 0.01). These results show that presence of TMA and TGA influence the prognosis of patients with hyperthyroidism treated with methimazole with regard to relapse. Those patients who had both antibodies were least likely to have a relapse and those who had neither antibody before and during treatment were most likely to have a relapse of hyperthyroidism.

Predictor of outcome of hyperthyroidism due to Graves disease: serum triiodothyronine/thyroxine ratio.

There is a proportionally greater increase in the serum T3 than Serum T4 concentration in patients with hyperthyroidism due to Grave's disease which results in an elevation of serum T3 to T4 ratio. The study was undertaken to investigate the alteration of serum T3 to T4 ratio in relation to the outcome of antithyroid drug therapy. 98 patients of hyperthyroid Grave's disease were studied and 78 patients had T3 to T4 ratio greater than 20 ng/microgram before therapy (normal range 14-20; mean 16.0) In 16 out of 78 patient T3 to T4 ratio remained high during a 18 months course of antithyroid drug therapy and in 13 of them (81%) hyperthyroidism recurred after stoppage of treatment. In the remaining 62 patients, the initial high T3 to T4 ratio became normal (< 20) during treatment and 34 of them (54.9%) had a remission of the disease after stoppage of the drug. Of the 20 patients in whom the initial T3 to T4 ratios were within normal range, the ratio remained normal during treatment and 16(80%) had a remission. Goiter size was larger in patients with high serum T3 to T4 ratio and reduction of goiter size occurred in some patients (59%) with decreasing T3 to T4 ratios. It is concluded that serum T3 to T4 ratio is a single and a useful predictor of the outcome of antithyroid drug therapy in patients with hyperthyroidism due to Grave's disease. A ratio greater than 20 throughout therapy indicates that the chances of relapse is high and a ratio below 20 either initially or during therapy is an indication of prolonged remission.