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PubMed1976

Thyroid-stimulating immunoglobulins and the control of thyroid function.

Triiodothyronine (T3) suppression and thyrotropin-releasing hormone (TRH) tests were used to study thyroid function in 50 patients with thyroid disease. The results of the thyroid function tests were compared with the levels of serum thyroid-stimulating immunoglobulins (TSI) measured by a radio-receptor assay. In euthyroid and hyperthyroid patients, the presence of TSI corresponded with the absence of TSH control of thyroid function. However, in two hypothyroid patients with serum TSI levels readily detectable in the receptor assay, T3 suppression and TRH tests indicated that thyroid function was under TSH control.

Adult↗
PubMed1982

Evidence for species specificity in the interaction between thyrotropin and thyroid-stimulating immunoglobulin and their receptor in thyroid tissue.

The cAMP response in cultured human and dog thyroid cells was used to examine the relationship between human TSH, nonprimate TSH, and thyroid-stimulating immunoglobulin (TSI) bioactivity in human and nonhuman thyroid tissue. The bovine TSH (bTSH) to human TSH potency ratio was approximately 6-fold greater in dog than in human thyroid cells. Relative bioactivity of bTSH and TSI aslo differed in these cell types. Thus, four TSI samples produced approximately 6-fold greater stimulation relative to bTSH in human thyroid than in dog thyroid cells. It is discussed why these data suggest that the TSH receptor as well as TSH and TSI display species specificity as defined by the classical concept of this term.

Animals↗
PubMed1983

Functionality of thyroid-stimulating antibodies assessed by cryopreserved human thyroid cell bioassay.

Immunoglobulin preparations from patients with autoimmune thyroid disease may inhibit the binding of 125I-labeled bovine TSH to solubilized TSH receptors without exhibiting concurrent thyroid stimulation. Such data have emphasized the continuing need for assay of biological function in addition to binding inhibition. We have employed a convenient technique using normal human thyroid cells cultured in monolayers for 7 days and then cryopreserved in liquid N2. Thyroid stimulation was assessed by measuring intracellular cAMP accumulation in a modified hypotonic Hank's Balanced Salt Solution using approximately 30,000 cells/well. Forty-five consecutive unselected immunoglobulin samples from hyperthyroid Graves' patients were assayed at 10 mg/ml protein for 2 h. Thirty-two (71%) of these untreated samples and 3 of 13 (23%) samples from treated euthyroid Graves' patients caused significantly greater stimulation than normal Ig prepared and assayed simultaneously. Forty-four percent of the positive samples were of low titer, causing less than a 200% increase in basal cAMP levels. One high titer sample (12,000% increase) had even greater bioactivity when serially diluted, thus suggesting the presence of an inhibitor, a phenomenon not observed in 20 lower titer and negative preparations. These data indicate the convenience and usefulness of a cryopreserved thyroid cell bioassay and emphasize that only low titers of thyroid-stimulating antibody occur in the peripheral circulation of many Graves' patients.

Adult↗
PubMed1990

Studies with purified human thyroid peroxidase and thyroid microsomal autoantibodies.

We have isolated highly purified thyroid peroxidase (TPO) from human thyroid tissue to study further the relationship between TPO and the thyroid microsomal antigen that elicits the production of microsomal autoantibodies in patients with autoimmune thyroid disease. Serum samples were obtained from 24 patients with suspected autoimmune thyroid disease, and from 7 normal subjects. Microsomal autoantibodies in the patient sera, as determined by the microsomal hemagglutination assay (MCHA), varied between 1:100 and 1:102,400. Antithyroglobulin antibodies, however, were very low (less than 1:100). Binding of serum autoantibodies to purified human TPO, as determined by enzyme-linked immunosorbent assay, correlated fairly well with MCHA titers (r = 0.72; P less than 0.001). An immunoblot procedure was developed to study the binding of serum antibodies to the major active fragment of TPO (93 kDa), after sodium dodecyl sulfate-polyacrylamide gel electrophoresis under both reducing and nonreducing conditions. Binding under both conditions correlated very well with MCHA titers (r = 0.80-0.84; P less than 0.001). Studies were performed to determine the inhibitory effect of patient serum on the enzymatic activity of purified human TPO. A marked inhibitory effect on guaiacol activity was observed when TPO was preincubated with as little as 10 microL high titer serum. There was a significant correlation (r = 0.47; P less than 0.01) between MCHA titer and inhibitory effect. The addition of 2 micrograms purified human TPO completely or almost completely inhibited the binding of serum antibodies to thyroid microsomes (enzyme-linked immunosorbent assay) in 10 of 11 patient sera with high MCHA titers (1:25,600 or greater).

Antibody Formation↗
PubMed1993

Expression levels of the thyrotropin receptor gene in autoimmune thyroid disease: coregulation with parameters of thyroid function and inverse relation to major histocompatibility complex classes I and II.

Using a human TSH receptor (TSH-R) cDNA probe, we investigated TSH-R transcript levels in 13 human thyroid fragments by Northern blot analysis; 7 Graves' disease, 2 Hashimoto's disease, 3 endemic goiter, and 1 healthy thyroid gland were studied. TSH-R expression levels were variable, but displayed a close correlation to the expression of thyroid peroxidase (r = 0.703; P < 0.05), thyroglobulin (r = 0.817; P < 0.01), and the nuclear oncogene c-fos (r = 0.935; P < 0.001), but not c-myc. Overall, TSH-R transcript levels were low or absent in those thyroids in which expression of the major histocompatibility complex class I or II (MHC I or II) was high, thus establishing an inverse relation (MHC I, r = -0.791; P < 0.01; MHC II, r = -0.784; P < 0.01). In situ hybridization showed that apart from lymphocytes, thyroid cells themselves were the source of MHC II transcripts. gamma-Interferon expression was only detectable in 1 Hashimoto's goiter. Our findings suggest that next to lymphocyte infiltration, active regulatory events in the thyrocyte are responsible for the inverse relation between functional parameters (TSH-R, thyroid peroxidase, thyroglobulin, and c-fos) and immunological markers (MHC I and II).

Adolescent↗
PubMed1994

A new point mutation (C446R) in the thyroid hormone receptor-beta gene of a family with resistance to thyroid hormone.

Resistance to thyroid hormone (RTH) is a condition of impaired end-organ responsiveness to thyroid hormone characterized by goiter and elevated thyroid hormone levels with an inappropriately normal TSH. RTH has been associated with mutations in the thyroid hormone receptor-beta (TR beta) gene. We report studies carried out in 21 members of a family (F119), 12 of whom exhibited the RTH phenotype. A point mutation was detected in the T3-binding domain of the TR beta gene. It resulted in replacement of the normal cysteine-446 with an arginine (C446R) that has not been previously reported. The clinical characteristics of this family are similar to those reported in other families with RTH, namely goiter, tachycardia, and learning disabilities. Thyroid function tests are also typical of other subjects with RTH. The mean values (+/- SD) in untreated affected subjects compared to those in unaffected family members were: free T4 index, 250 +/- 21 vs. 108 +/- 13; total T3, 4.3 +/- 0.4 vs. 2.4 +/- 0.4 nmol/L; and TSH, 4.5 +/- 1.1 vs. 2.4 +/- 1.1 mU/L. DNA samples from 18 family members were screened for the TR beta mutation, which results in the loss of a BsmI restriction site, and each of the 11 subjects with abnormal thyroid function tests were heterozygous for the mutant allele. The mutant TR beta expressed in Cos-I cells did not bind T3 (Ka of C446R/wild-type, < 0.05). T3 at a concentration up to 100 nmol/L failed to enhance the transactivation of a reporter gene, and the mutant receptor inhibited the T3-mediated transcriptional activation of the wild-type TR beta.

Adolescent↗
PubMed1995

Potent thyrotropic activity of human chorionic gonadotropin variants in terms of 125I incorporation and de novo synthesized thyroid hormone release in human thyroid follicles.

Using a highly sensitive bioassay for TSH, in which human thyroid follicles incorporate 125I and release de novo synthesized thyroid hormone into the culture medium, the thyrotropic activities of various hCG preparations were studied. Under the culture conditions employed, bovine TSH (bTSH) was approximately 6- to 9-fold more active than human TSH (hTSH). Highly purified hCG prepared from urine of normal pregnant women (CR 127) had only a trivial thyrotropic activity equipotent to 0.00022 microU bTSH/U hCG or 0.0013 microU hTSH/U hCG (19.7 microU hTSH/mg hCG). Hybrid hCG (AB1ER) also elicited low thyrotropic activity (14.0 microU hTSH/mg), whereas crude hCG had moderate thyrotropic activity (0.041 hTSH microU/U hCG or 127 microU/mg protein). Deglycosylated hCG, a very weak LH/hCG receptor agonist, was the most potent agonist in thyroid follicles (588 microU hTSH/mg protein). hCGs purified from urine of patients with trophoblastic tumors had greater TSH-like activity (37-84 microU hTSH/mg protein) than purified hCG. Asialo-hCG purified from a patient with choriocarcinoma had very potent TSH-like activity (468 microU hTSH/mg). Submaximal doses of bTSH and hCG variants produced additive stimulation of thyroid function. Furthermore, the thyrotropic effect of hCG was inhibited by anti-TSH receptor antibody obtained from patients with myxedema. These in vitro findings suggest that although hCG is reported to exert potent cAMP-stimulating activity on rat thyroid-like cells (FRTL-5) and Chinese hamster ovary cells transfected with hTSH receptor complementary DNA (0.092-0.72 microU hTSH/U hCG), the thyrotropic activity induced by authentic hCG in human thyroid follicles is too weak to cause hyperthyroidism in normal pregnancy. However, hCG produced by some trophoblastic tumors, particularly asialo-hCG, has potent thyrotropic activity sufficient to cause clinically overt hyperthyroidism when produced excessively.

Animals↗
PubMed1998

Is human leukocyte antigen-DR and intercellular adhesion molecule-1 expression on human thyrocytes constitutive in papillary thyroid cancer? Comparative studies in human thyroid xenografts in severe combined immunodeficient and nude mice.

We have studied human leukocyte antigen (HLA)-DR and intercellular adhesion molecule (ICAM)-1 expression on thyroid epithelial cells (TEC) from papillary thyroid carcinoma (PTC) tissues xenografted into two different mouse strains [the severe combined immunodeficient (SCID) mouse, which accepts human tissue with lymphocytes; and the nude mouse, which accepts the tissue but destroys all passenger lymphocytes]. Human PTC [PTC/TIL (PTC with tumor infiltrating lymphocytes) and PTC/PTC (PTC without tumor infiltrating lymphocytes)], Graves' disease (GD), and normal thyroid (N) tissues were xenografted sc into 22 SCID and 21 nude mice. Blood samples were taken every 2 weeks for measurement of human IgG and thyroid antibodies. Seven weeks after xenografting, xenografted thyroid tissues were analyzed for thyrocyte HLA-DR and ICAM-1 expression. SCID mice xenografted with PTC/TIL (PTC/TIL-SCID) manifested IgG production for 6 weeks, but nude mice showed diminished and disappearing IgG production from these xenografts. Thyroperoxidase (TPO)-antibody (Ab)(TPO-Ab) was not detectable in PTC/TIL-SCID despite the presence of TPO-Ab in some donors. Thyroglobulin-Ab (Tg-Ab) was detectable in all mice of PTC/TIL-SCID. Thyrocyte HLA-DR expression from PTC-SCID was markedly increased, compared with that from nude mice xenografts or from N xenografts in SCID mice. In addition, thyrocyte HLA-DR expression from PTC-nude was markedly increased, compared with the expression seen in GD-nude and N-nude xenografts. ICAM-1 expression on TEC from PTC xenografts in the SCID mouse was markedly increased, compared with N xenografts. ICAM-1 expression on TEC from PTC did not show any difference between SCID and nude mice. ICAM-1 expression on TEC from PTC xenografts in the nude mice was markedly increased, compared with those from GD and N xenografts. In conclusion, TIL in PTC produce Tg-Ab but do not produce TPO-Ab. HLA-DR expression on TEC from PTC is strongly constitutive, but it is also affected by TIL. TIL might have some role in control of PTC through partial expression of HLA-DR on TEC. ICAM-1 expression on TEC from PTC seems to be entirely constitutive, and it is not affected by the presence of local lymphocytes, in contrast to autoimmune thyroid disease.

Animals↗
PubMed1998

B7.1 costimulatory molecule is expressed on thyroid follicular cells in Hashimoto's thyroiditis, but not in Graves' disease.

The molecules of the B7 family play a major role in T-lymphocyte costimulation through interaction with their counterreceptors CD28 and CTLA4. In the present study, we analyzed the possible expression of B7 molecules on surgically removed thyroid tissue of patients with autoimmune [Hashimoto's thyroiditis (HT) or Graves' disease (GD)] or nonautoimmune [nontoxic goiter (NTG) or papillary cancer (PC)] thyroid diseases. We found clear positivity of thyroid follicular cells for B7.1 in HT but not in GD, nor in nonautoimmune specimens (NTG, PC) using in situ analysis by alkaline phosphatase anti-alkaline phosphatase (APAAP) technique. Double immunostaining experiments in combination with an anti-human thyroglobulin antibody confirmed follicular B7.1 localization. On the contrary, no follicular B7.2 expression was observed in any specimen analyzed. These findings were confirmed by immunofluorescence flow cytometry on isolated follicular cells. The cytokines IL1beta and LPS were able to induce de novo B7.1 expression on cultured thyroid follicular cells. Intrathyroid T cells proved responsive to stimulation via the B7 ligand CD28, even in the absence of IL2. Moreover preliminary evidence was obtained for an inhibitory effect of anti-B7.1 mAb on T-cell proliferation in coculture with isolated thyroid follicular cells. It is conceivable that in HT, expression of B7.1 on follicular cells, together with MHC class II antigens and ICAM1, could provide a local costimulatory signal for T-lymphocyte differentiation toward the type 1 cytokine secretion pattern and maintenance of the autoimmune process.

Adult↗
PubMed2000

Postpartum thyroid dysfunction in pregnant thyroid peroxidase antibody-positive women living in an area with mild to moderate iodine deficiency: is iodine supplementation safe?

In moderately iodine-deficient, pregnant, thyroid peroxidase antibody (TPO-Ab)-positive women the role of iodine supplementation in the development of postpartum thyroid dysfunction (PPTD) was studied in a placebo-controlled, randomized, double blind trial. Screening for TPO-Ab was performed in early pregnancy in a population of healthy pregnant Danish women with no previous diagnosed thyroid disease (prevalence, 117 of 1,284; 9.1%). The participants were randomized, stratified according to TPO-Ab level, to three groups. All participants received a daily vitamin and mineral tablet with 150 microg iodine or no iodine. The +/+ group received iodine during pregnancy and the postpartum period, the +/- group received iodine during pregnancy only, and the -/- group received no iodine supplementation. A total of 66 TPO-Ab positive women were followed, and in the postpartum period sera were collected at 8-week interval for biochemical evaluation of thyroid function and antibody level. Compliance was evaluated by 24-h urinary iodine measurements. PPTD developed in 55% of the participants. In 67% of the cases abnormal TSH was accompanied by abnormalities in thyroid hormones, whereas 33% had abnormal serum TSH only. There was no statistically significant difference in the frequency of PPTD in the three groups: +/+ group, 59% (95% confidence interval, 36-79%); +/- group, 60% (36-81%); and -/- group, 46% (26-67%). There were also no differences in the severity of the PPTD, as evaluated by duration and grade of deviation of TSH and thyroid hormones from normality. The occurrence, severity, and type of PPTD predominantly depended on the TPO-Ab level: TPO-Ab below 200 U/L at screening, 35% developed PPTD; TPO-Ab of 200-900 U/L, 54%; and TPO-Ab above 900 U/L, 75% developed PPTD. Women with low levels of antibodies predominantly remained euthyroid or had hyperthyroidism only, whereas women with high antibody levels had hyperthyroidism followed by hypothyroidism or hypothyroidism only. We conclude that iodine supplementation (150 microg) during pregnancy and the postpartum period to TPO-Ab-positive women living in an area with mild to moderate iodine deficiency did not induce or worsen PPTD. The study confirmed that screening for TPO-Ab in early pregnancy can predict women at high risk for development of PPTD.

Adult↗
PubMed2002

A solitary minute thyroid lymphoma of MALT-type without lymphoid thyroiditis.

Most of the primary thyroid malignant lymphomas have been considered of mucosa-associated lymphoid tissue (MALT) type and arise from lymphocytic thyroiditis. We report an uncommon case of a 67-yr-old man who underwent total thyroidectomy for multinodular goiter with tracheal compression. At histopathologic examination, we discovered a minute (3-mm diameter) lesion of low-grade thyroid lymphoma of MALT type without any lymphocytic thyroiditis lesion on 33 section levels of the entire thyroid gland. No general inflammatory, autoimmune, or lymphomatous disorder has been evidenced both at staging and after 30 mo of follow-up. MALT-type low-grade lymphoma may, in some instances, develop de novo within the thyroid without an antecedent MALT-type lymphoma.

Aged↗
PubMed2006

Thyroid peroxidase immunohistochemistry in differential diagnosis of thyroid tumors.

Thyroperoxidase (TPO) is a thyroid-specific enzyme expressed by differentiated thyroid cells. Initial immunohistochemical studies claimed that TPO expression, detected by the monoclonal antibody mAb 47, may be a potentially important diagnostic tool in differentiating malignant from benign lesions. However, some recent studies have failed to reproduce the earlier results, suggesting the limitations for TPO immunohistochemistry. To assess these observations we have evaluated the immunohistochemical expression of TPO in thyroid tissue from 215 patients. The studied material included 87 nonmalignant thyroid lesions and 128 thyroid carcinomas. TPO expression was investigated using newly available mAb 47 and staining of less than 80% of the follicular cells/specimen as the threshold indicating a malignant lesion. We found that TPO had a sensitivity of 89.9% for cancer and a specificity of 64.4% for nonmalignant lesions, showing that it does not give a sufficient degree of diagnostic certainty that the lesion is benign. In addition, the variability in the degree of TPO expression found within and between follicular carcinomas, and the significant number of benign adenomas having similar immunostaining patterns, assured us that TPO immunostaining is not sufficiently discriminatory in the differential diagnosis of thyroid cancer versus benign lesions.

Adenoma↗
PubMed1988

[Characterization of thyroglobulin and thyroid peroxidase activity in patients with functioning thyroid benign tumors].

The content and chemical and immunological properties of thyroglobulin (Tg) and the activity of thyroid peroxidase (TPO) were studied in nodular and extranodular (periphery) thyroid tissue from patients with functioning thyroid tumors (hot nodules). From the present observations, the tumor extracts contained fairly large amounts of Tg, similar to that in the periphery tissue, while the content of Tg was markedly decreased in non-functioning thyroid tumors (cold nodules). The iodine content of Tg was significantly higher in nodular tissue compared with periphery tissue. These observations were in contrast to the results seen in the cold nodules in which hormone synthesis was defective. On the nature of carbohydrate moiety as compared with normal tissue, oligosaccharides of Tg from the periphery tissues changed in a manner similar to that of tumor oligosaccharides. That is, high-mannose type oligosaccharides were markedly decreased whereas multiantennary and unidentified oligosaccharides were increased. These observations were similar to those of non-functioning tumors. The content of sialic acid decreased markedly both in the tumor and periphery tissues. Immunologically, Tg preparations of the tumor and periphery tissue did not show the same affinity to the antibodies, depending on the content of iodine. Therefore, it seems that the contribution of the iodine content and iodo-amino acid has little or no significance in the heterogeneous nature of Tg-immunogenecity. Benign tumors and the periphery tissue were subjected to assay for thyroid peroxidase activity by the method employing guaiacol as the second substrate. The specific activities of the tumors were generally higher than those of periphery tissues, both in functioning and non-functioning benign tumors. In non-functioning carcinoma, on the other hand, TPO activities were lower in tumor portions than in periphery portions. This indicates that non-functioning thyroid carcinomas have a different characteristic.

Adenoma↗
PubMed1997

Clinical courses and thyroid conditions in three infants born to a mother with thyroid stimulating-blocking antibodies.

The clinical courses including thyroid conditions of three infants born to a mother with primary hypothyroidism due to Hashimoto's thyroiditis were studied. The mother was positive for both TSH-binding inhibitor immunoglobulins (TBII) and thyroid stimulating-blocking antibodies (TSBAb) in her serum. The first infant died because of septic shock due to fistula formation between the large intestine and the bladder. Serum thyroid hormone levels during the first pregnancy were extremely low because of incomplete replacement therapy with levothyroxine. The second infant had almost normal thyroid function, so that the replacement therapy was not necessary. The third infant had transient and overt primary hypothyroidism. The replacement therapy was carried out for six months after birth. TSBAb activities in this mother were high in the third pregnancy. In general, these activities gradually increases with the clinical course in TSBAb-positive Hashimoto's patients. From these findings, it was suspected that the thyroid conditions in the second and the third infants reflected the natural course of TSBAb activities in this mother.

Adult↗
PubMed1997

A case of acute exacerbation of Hashimoto's thyroiditis with a nontender thyroid.

We report a 54-year-old female with high grade fever, fatigue, and painless swelling of the thyroid gland. Based on findings of high gallium-67 citrate uptake in an enlarged thyroid gland accompanied by severe systemic inflammation including an increase in various cytokines and histology of biopsied specimens indicating typical chronic thyroiditis, a diagnosis of acute exacerbation of Hashimoto's thyroiditis was made. All clinical symptoms were relieved by oral naproxen following a prolonged hypothyroid status. This may be the first case report describing painless acute exacerbation of Hashimoto's thyroiditis, and may provide insight into the clinical spectrum of acute inflammatory reactions in Hashimoto's thyroiditis.

Acute Disease↗
PubMed2006

Thrombospondin 1 mRNA as a candidate for a marker to detect thyroid-derived fibroblasts in fine needle aspiration biopsy of the thyroid.

Possible interference of fibroblasts is suggested in aspiration biopsy nucleic acid diagnosis (ABND). However, detection of fibroblasts in the aspirates is difficult, because the gene expression profiles of thyroid malignancies and fibroblasts are much alike in many aspects. To identify a specific marker for thyroid-derived fibroblasts, the data of the serial analysis of gene expression (SAGE) were compared to screen differentially expressed genes between fibroblasts and thyroid normal and tumor tissues. In the SAGE data, 5 genes were identified to be differentially expressed. Among these, thrombospondin 1 (TSP-1, THBS1) mRNA was the most differentially expressed. Further, the overexpression of TSP-1 mRNA in fibroblasts was confirmed by real-time RT-PCR analysis using 73 thyroid normal and tumor tissues and 7 cultures of thyroid-derived fibroblasts. These results suggest that TSP-1 mRNA is a possible marker for contamination of thyroid-derived fibroblasts.

Biomarkers↗
PubMed2006

Use of recombinant human thyroid-stimulating hormone in the management of well-differentiated thyroid cancer.

Recombinant human (rh) thyroid-stimulating hormone (TSH) has changed the care of patients with well-differentiated thyroid cancer (DTC). Traditionally, thyroid hormone withdrawal has been used to increase TSH concentrations for optimising trapping and retention of radioiodine for thyroid remnant ablation and for diagnostic procedures (measurement of thyroglobulin and whole body scan) used in the follow-up of patients with DTC. The resulting hypothyroidism is, however, accompanied by substantial morbidity. rhTSH is an effective and safe alternative to thyroid hormone withdrawal for follow-up of DTC. Its ability to detect persistent or recurrent disease is similar to that of thyroid hormone withdrawal. At the present time, rhTSH is approved for diagnostic monitoring of patients with DTC as well as for pretherapeutic stimulation in low-risk patients for remnant ablation with 100 mCi (131)I (in the EU). In addition, rhTSH has potential for use in facilitating the treatment of metastasis in patients with DTC and in patients with non-toxic nodular goiter; however, more clinical trials are needed to confirm its use in these situations.

Animals↗
PubMed1978

A case of Hashimoto's thyroiditis with thyroid immunological abnormality manifested after habitual ingestion of seaweed.

An interesting case of iodide induced goitre with immunological abnormalities is described. The patient who was sensitive to synthetic penicillin had previously been treated for exudative pleuritis, congestive heart failure and acute renal failure. Following recovery, he began to ingest large amounts of seaweed after which he developed goitrous hypothyroidism. It was of interest that the serum level of gamma-globulin increased, and subsequently the antithyroid microsomal antibody became strongly positive, suggesting that thyroidal autoimmune processes had been precipitated. Biopsy of the thyroid gland revealed chronic thyroiditis, with evidence suggesting extreme stimulation by TSH. Hight thyroidal uptake of 131I, positive perchlorate discharge test and biochemical analysis of the thyroidal soluble protein showed severe impairment of hormone synthesis following continuous accumulation of excess iodide. While there is evidence suggesting that increased iodide may be an important factor in the initiation of Hashimoto's thyroiditis, this may result from the marked increased sensitivity of Hashimoto's gland to the effects of iodine. Thus an occult lesion could be unmasked in this manner. The mechanism by which iodide mediates this effect is not clear.

Adult↗