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R Minelli

Publications and source records attributed to R Minelli.

At least 19 recordsLinked to original sources
PubMed2006

Coexistence of TSH-secreting pituitary adenoma and autoimmune hypothyroidism.

OBJECTIVE: TSH-secreting pituitary adenomas account for about 1-2% of all pituitary adenomas. Their diagnosis may be very difficult when coexistence of other diseases masquerades the clinical and biochemical manifestations of TSH-hypersecretion. CLINICAL PRESENTATION: A 41-yr-old female patient, weighing 56 kg, was referred for evaluation of an intra- and suprasellar mass causing menstrual irregularities. Eight yr before, the patient had been given a diagnosis of subclinical autoimmune hypothyroidism because of slightly elevated TSH levels and low-normal free T4 (FT4). Menses were normal. Despite increasing doses of levo-T4 (L-T4; up to 125 microg/day), TSH levels remained elevated and the patient developed mild symptoms of hyperthyroidism. After 7 yr, the menstrual cycle ceased. Gonadotropins were normal, whereas PRL level was elevated at 70 microg/l and magnetic resonance imaging (MRI) of the hypothalamic- pituitary region revealed a pituitary lesion with slight suprasellar extension. The tumor was surgically removed and histological examinations revealed a pituitary adenoma strongly positive for TSH. Three months after surgery the patient was well while receiving L-T4 75 microg/day and normal menses had resumed. MRI of the hypothalamic-pituitary region showed no evidence of residual tumor. At the last follow-up, 16 months after surgery, serum TSH, free T3 (FT3), and FT4 levels were normal. CONCLUSIONS: Coexistence of autoimmune hypothyroidism and TSH-secreting pituitary adenoma may cause further delays in the diagnosis of the latter. In patients with autoimmune hypothyroidism, one should be aware of the possible presence of a TSH-secreting pituitary adenoma when TSH levels do not adequately suppress in the face of high doses of L-T4 replacement therapy and elevated serum thyroid hormone levels.

Adenoma↗
PubMed2003

Maedi-visna virus detection in ovine third eyelids.

Maedi-visna is a systemic disease of sheep caused by a lentivirus, maedi-visna virus (MVV), which mainly affects the lungs and central nervous system but may also affect the mammary glands, joints and other tissues. The aim of the present study was to determine whether the third eyelid was affected in cases of systemic infection. Third eyelid and lung samples from sheep naturally infected with maedi were used. Total DNA was extracted from paraffin-wax-embedded tissues, and a nested polymerase chain reaction (PCR) was performed to amplify MVV proviral DNA. The samples were also tested by in-situ PCR and immunohistochemical methods specific for the detection of MVV proviral DNA and p25, respectively. All sheep showed moderate to severe chronic lymphoproliferative inflammation in the third eyelids. Products of the expected size were obtained by PCR from both lung and third eyelid tissue. In the nictitating membrane, MVV proviral DNA was detected in situ within macrophages, and glandular, ductal and surface epithelia. Immunohistochemistry demonstrated that the infection was productive. Taken together, these results indicate that the third eyelid may represent a target for natural MVV infection and may play a role in disease transmission.

Animals↗
PubMed2001

Fulminant autoimmune Type 1 diabetes during interferon-alpha therapy: a case of Th1-mediated disease?

AIM: A case of autoimmune Type 1 diabetes with some unique characteristics developing in a 29-year-old male during treatment with interferon-alpha (IFN-alpha) for chronic hepatitis C virus (HCV) hepatitis is reported. PATIENT AND METHODS: In this patient IFN-alpha treatment was well tolerated and successful in the cure of hepatitis with eradication of HCV infection within 3 months, but at 8.5 months Type 1 diabetes appeared and insulin therapy was started and maintained thereafter. HLA class II molecular typing was determined and retrospective measurement of islet cell (ICA), glutamate decarboxylase (GADA), tyrosin phosphatase IA-2 (IA-2A) and insulin (IAA) antibodies was performed in serum samples obtained before and at 0.5, 1, 2, 3, 4, 5, 6, 8.5, 10 and 13 months after the beginning of IFN-alpha treatment. RESULTS: Complete HLA class II typing was consistent with homozygosity for the HLA DRB *03011, DQA1 *0501, DQB1 *0201 haplotype. All autoantibodies were undetectable prior to IFN-alpha therapy and remained undetectable up to 6 months of treatment; at 8.5 months, at the time of diabetes onset, ICA were detectable at low titre while GADA were present at high titre. Both ICA and GADA persisted at high levels in subsequent samples. IA-2A remained undetectable in all serum samples, while IAA appeared only after treatment with exogenous insulin. DISCUSSION: This appears to be a case of autoimmune Type 1 diabetes induced by IFN-alpha treatment and developing on a predisposed genetic background with an unusually rapid development of the autoimmune process as reflected by the absence of detectable autoantibodies up to 2.5 months prior to disease onset. In this example of fulminant Type 1 diabetes a pathogenic process unbalanced towards a Th1-mediated autoimmune response is hypothesized. Diabet. Med. 18, 329-332 (2001)

Adult↗
PubMed2000

Thyroid hormone metabolism in obesity.

Serum thyroid hormone concentrations and their metabolic fate are within the normal range limits in obese subjects. Also serum TSH concentrations and its response to TRH are normal, suggesting that tissue availability of thyroid hormones is normally preserved in these subjects. In contrast, during caloric restriction serum T3 concentrations decrease as a consequence of its reduced production rate from peripheral deiodination of T4. Opposite, serum rT3 concentrations markedly increase as a result of its decreased metabolic clearance rate. During caloric overfeeding serum T3 concentration increase whereas serum rT3 concentrations decrease. In this condition the production rate of T3 increases. During caloric restriction and overfeeding serum T4 concentrations and its production and degradation are not modified.

Energy Intake↗
PubMed2000

Serum concentrations of proinflammatory cytokines in Graves' disease: effect of treatment, thyroid function, ophthalmopathy and cigarette smoking.

OBJECTIVE: In the present study we have measured the concentrations of interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) and IL-1 receptor antagonist (IL-1Ra) in the serum of patients with Graves' disease (GD). By multivariate analysis, we have evaluated the effect of antithyroid treatment, thyroid function, the presence or absence of active thyroid-associated ophthalmopathy (TAO), the patient's smoking habits and the relation to circulating anti-thyrotropin (TSH) receptor (TRAb) and anti-thyroperoxidase antibodies (TPOAb). SUBJECTS: We studied 84 GD patients, 51 untreated and 33 receiving methimazole (MMI) therapy. Twenty-three (45%) untreated patients and 18 (54%) patients on MMI had active TAO. We also studied 67 normal subjects as controls. Thirty-one GD patients (43%) and 16 controls (36%) were smokers. RESULTS: Serum IL-6 concentrations were significantly higher in both untreated patients (P<0.001) and treated patients (P<0.006), when compared with controls. Serum sIL-6R concentrations were significantly affected by treatment (P=0.001). Serum IL-1Ra concentrations were not different in GD patients, whether treated or untreated, compared with controls. Serum IL-6 concentrations were not influenced by thyroid function and there was a significant interaction between treatment and the presence of active TAO (P=0.003). In hyperthyroid patients with active TAO serum, sIL-6R concentrations were significantly higher than in those with inactive TAO (P=0.003). In untreated GD patients there was no significant effect of thyroid function and TAO activity on the serum concentrations of TNF-alpha and IL-1 beta. Serum IL-1Ra concentrations were not affected by the presence of TAO. Smoking had no effect on serum IL-6, sIL-6R, TNF-alpha, IL-1 beta and IL-1Ra concentrations, even in the presence of an active TAO. Serum concentrations of IL-6, sIL-6R, TNF-alpha and IL-1 beta and IL-1Ra were not different in patients with and without TRAb or TPOAb, in relation to either thyroid function, TAO activity or smoking. CONCLUSIONS: Our work shows that: (i) the proinflammatory cytokine pattern in GD is greatly influenced by antithyroid drug treatment; (ii) the increased circulating IL-6/sIL-6R concentrations observed in patients with active TAO may derive from the activation of humoral reactions in sites other than the thyroid; and, (iii) cigarette smoking has no effect on serum IL-1/IL-1Ra concentrations in TAO.

Adolescent↗
PubMed1999

Are thyroid function tests too frequently and inappropriately requested?

In spite of data supporting the use of the serum thyrotropin (TSH) concentration as the best test to detect abnormal thyroid function, measurement of circulating thyroid hormones with or without a serum TSH continues to be frequently requested to evaluate thyroid function. We have analyzed how combinations of thyroid function tests were ordered by referring physicians and the results of the tests in order to offer some suggestions as to how to use thyroid function tests in a cost effective manner. During 1995, 19,181 inpatient and outpatient requests (45,865 different tests) for thyroid function tests were received by the laboratory of a 1600 bed University Hospital in Parma, Italy. The following tests were carried out: T4, free T4, T3, free T3 and TSH. Serum TSH values below and above the normal range were considered to reflect abnormal thyroid function i.e. hyperthyroidism, or hypothyroidism including subclinical disease independent of the results of the other tests. Combinations of ordered tests and the percent of the total for each combination were: TSH+T4+T3 (56%), TSH+FT4+FT3 (14%), TSH (12%), TSH+FT4 (9%), TSH+T4 (1%), TSH+T4+T3+FT4+FT3 (5%), others (3%). The T4+T3+TSH panel (10,780 requests) had normal serum TSH values in 80.6% and the FT4+ FT3+TSH panel (2,590 requests) had normal TSH values in 73.2%. Elevated serum TSH concentrations were observed more frequently in hospitalized than in ambulatory patients (9.7% vs 7.4% p<0.001). T3 (elevated serum T3, normal T4 and low TSH concentrations) and T4 (elevated serum T4, normal T3 and low TSH concentrations) toxicosis were observed in 8.1% and 9.4%, respectively, of the requested test (NS). FT3 and FT4 toxicosis, defined as for T3 and T4 toxicosis, were observed in 7.5% and 4.9%, respectively (NS). The low T3 and low FT3 syndrome in hospitalized patients was present in 1.6% and 2.3% of the requests, respectively (NS). The low T4+low T3 and low FT4+low FT3 syndrome was present in only 0.3% and 0.2%, respectively, of the requests. Our study shows that a) in hospitalized patients thyroid function tests were requested in 20% of the patients and only one in 14 of these patients at the highest could have abnormal thyroid function, as indicated by abnormal TSH value b) FT4 (or T4) is as useful as FT3 (or T3) in the diagnosis of hyperthyroidism, c) in hospitalized patients the low T3 syndrome was far less common than that reported in the literature, probably due to the lower severity of illness, d) panels which include T3 and FT3 are not justified, and e) serum TSH alone is the most appropriate initial thyroid function test.

Cost-Benefit Analysis↗
PubMed1999

Recombinant interferon alpha (rIFN-alpha) does not potentiate the effect of iodine excess on the development of thyroid abnormalities in patients with HCV chronic active hepatitis.

OBJECTIVE: To determine whether the administration of pharmacological quantities of iodine during interferon-alpha (rIFN-alpha) treatment of chronic viral hepatitis B and C (HCV) would exacerbate the potential adverse effects of rIFN alpha on thyroid function. DESIGN: Thyroid function tests were carried out in 48 euthyroid patients before and during rIFN-alpha therapy of HCV. Twenty-one of these patients were also treated with 10 drops saturated solution of potassium iodine (SSKI, approximately 350 mg iodine daily). Eight patients with HCV but not treated with rIFN-alpha received 10 drops SSKI. PATIENTS: All patients were enthyroid prior to rIFN-alpha therapy for HCV or iodine and thyroid function tests were similar in the three groups. MEASUREMENTS: Serum free T4, free T3, and TSH concentrations were measured prior to and at 30 and 60 days of rIFN-alpha therapy in the three groups of patients. The serum TSH response to TRH was assessed before rIFN-alpha therapy and on day 60. Thyroid peroxidase antibodies were measured before and during therapy. RESULTS: During the 2-month study period, similar small but significant decreases in serum FT4 and FT3 and compensatory small significant increases in TSH concentrations were observed in the patients treated with rIFN-alpha + iodine and iodine alone but not in the patients receiving rIFN-alpha alone. Abnormal thyroid function tests were observed more frequently in patients receiving rIFN-alpha + iodine and iodine alone compared to those receiving rIFN-alpha alone. CONCLUSIONS: Excess iodine administered to patients treated with rIFN-alpha induced small changes in thyroid function similar to those observed in patients treated with iodine alone. Thus, rIFN-alpha and iodine do not appear to be synergistic in the development of abnormal thyroid function tests over a 2-month treatment period.

Adult↗
PubMed1997

Effects of excess iodine administration on thyroid function in euthyroid patients with a previous episode of thyroid dysfunction induced by interferon-alpha treatment.

OBJECTIVE: To determine the effects of pharmacological quantities of iodide (SSKI) on thyroid function in euthyroid patients previously treated with recombinant interferon-alpha (rIFN-alpha) for chronic viral hepatitis B and C (HCV), a cytokine which may induce thyroid dysfunction. DESIGN: Thyroid function tests were carried out in 16 euthyroid patients, 8 of whom had previously developed thyroid dysfunction during rIFN-alpha therapy for HCV, before, during and after the administration of 10 drops of saturated solution of potassium iodide (SSKI) (approximately 350 mg iodide). PATIENTS: All 16 patients had been treated in the past with rIFN-alpha for HCV. Eight patients had developed rIFN-alpha induced abnormalities in thyroid function (5 inflammatory thyrotoxicosis, 1 Graves' disease, and 2 impaired thyroid organification of iodide) and 8 had not developed thyroid dysfunction. MEASUREMENTS: After baseline serum free T4 (FT4) and free T3 (FT3) concentrations, basal and TRH stimulated TSH concentrations, and TSH-receptor (TSH-R-Ab) and thyroid peroxidase (TPO-Ab) antibodies were measured, 10 drops saturated solution of potassium iodide (SSKI, approximately 350 mg iodide) were given daily for 60 days and the above parameters assessed during and after SSKI was discontinued. RESULTS: Five of 8 patients with a previous history of rIFN-alpha induced thyroid dysfunction developed mild iodide induced abnormalities of thyroid function (subclinical hypothyroidism (slightly elevated basal and TRH stimulated serum TSH concentrations with normal serum FT4 and FT3 concentrations) or hyperthyroidism) compared with the 8 patients who had no previous evidence of thyroid dysfunction during rIFN-alpha therapy. CONCLUSIONS: In view of the present observations, it is prudent to avoid the administration of excess iodine to euthyroid subjects with a previous episode of thyroid dysfunction during rIFN-alpha therapy, adding a new group of patients susceptible to iodine induced thyroid disease.

Adult↗
PubMed1997

The study of visual evoked potentials in patients with thyroid-associated ophthalmopathy identifies asymptomatic optic nerve involvement.

In the present study we have recorded visual evoked cortical potentials (VECP) in 88 patients affected by autoimmune thyroid disease and thyroid-associated ophthalmopathy (TAO) without clinical signs of optic neuropathy. At the time of ophthalmological examination, 37 of these patients were hyperthyroid, 41 were euthyroid, and 8 were hypothyroid; 2 were not assessed. Twenty-nine normal subjects served as controls. We performed pattern reversal visual stimulation and recorded the amplitude and latency of the cortical electric response at 100 ms (P100 wave). There were no differences in the mean P100 amplitude of TAO patients and normal subjects. The mean P100 latency in patients was 105.6 +/- 0.5 ms, significantly higher than that in normal subjects (102.0 +/- 0.5 ms; P < 0.00003). Latency in euthyroid patients did not differ from that in either hypo- or hyperthyroid patients. The VECP test was positive (latency, > or = 110.0 ms) in 21 (23.8%) TAO patients. In patients with proptosis greater than 21 mm, latency was 106.7 +/- 0.7 ms, significantly higher than that in patients with normal Hertel measurements (104.3 +/- 0.6 ms; P < 0.01). Latency was not increased in patients with acute inflammatory signs compared to those with inactive eye disease and in patients with altered extrinsic motility. In patients with an abnormal visual field study, the mean latency was 110.3 +/- 1.5 ms, significantly higher than that in patients with a normal visual field (104.7 +/- 0.4; by t test, P < 0.000003). In conclusion, we observed a prolongation of the latency of the evoked cortical response in patients with TAO without subjective visual complaints and without optic nerve compression. We believe that the study of VECP in TAO is complementary to the study of the visual field in identifying early optic nerve dysfunction in the absence of decreased visual acuity.

Adolescent↗
PubMed1996

Multiple changes in thyroid function in patients with chronic active HCV hepatitis treated with recombinant interferon-alpha.

OBJECTIVE: Recombinant human interferon-alpha (r-IFN-alpha) is often successfully used in the treatment of patients with chronic viral hepatitis B and C. Thyroid dysfunction has been reported to occur with variable frequency during r-IFN-alpha therapy especially in patients with preexisting thyroid autoimmunity. We have prospectively evaluated the effect of r-IFN-alpha on various aspects of thyroid function in patients with HCV chronic hepatitis. DESIGN: Thirty-two patients with HCV chronic active hepatitis were studied prospectively before and during r-IFN-alpha therapy. Serum TSH, FT4, FT3, and thyroid receptor (TSR) and thyroid peroxidase (TPO) antibodies, and the iodide-perchlorate discharge test (I-C10(4)) to detect subtle defects in the thyroid organification of iodide were carried out during the study. Thyroid radioactive iodine uptakes (RAIU) were obtained in patients who developed thyrotoxicosis. RESULTS: All patients were clinically and biochemically euthyroid prior to r-IFN-alpha therapy with negative I-C10(4) discharge tests. Four patients became thyrotoxic, 3 secondary to destructive or inflammatory thyroiditis with a low thyroid RAIU, and 1 patient developed hypothyroidism. The I-C10(4) discharge test became positive in 7 of the 32 patients studied prospectively; 5 of these patients did not develop other evidence of thyroid dysfunction and did not have positive TPO antibodies. In these 5 patients the test became negative after r-IFN-alpha was discontinued. Appropriate therapy of the patients with thyrotoxicosis (methylprednisolone for 3 patients with destructive thyroiditis and methimazole for 1 patient with hyperthyroidism) or with hypothyroidism (L-thyroxine) was successful. CONCLUSIONS: Thyroid dysfunction, especially destructive or silent thyroiditis resulting in thyrotoxicosis, is not infrequently observed in patients receiving r-IFN-alpha therapy for chronic active hepatitis. Although underlying autoimmune thyroid disease appears to predispose patients to develop thyroid dysfunction, other patients become thyrotoxic or hypothyroid in the absence of baseline positive TPO-Ab. Subtle defects in the thyroidal organification of iodine as determined by the I-C10(4) discharge test, in the absence of autoimmune thyroid disease, was observed in 5 patients who remained euthyroid, suggesting that r-IFN-alpha directly reduces the intrathyroidal organification of iodine.

Adult↗
PubMed1996

Increased serum concentrations of interleukin-6 (IL-6) and soluble IL-6 receptor in patients with Graves' disease.

Increased serum interleukin-6 (IL-6) concentrations have been reported in patients with thyroid destructive processes. In the present study we measured IL-6 and soluble IL-6 receptor (sIL-6R) concentrations in the serum of normal subjects and patients with Graves' disease using a high sensitivity sandwich enzyme-linked immunoassay. We found increased serum IL-6 and sIL-6R concentrations (69.3 fmol/L, and 964 pmol/L, respectively) in 49 hyperthyroid patients with Graves' disease (GD) compared to those in controls [55.8 fmol/L (P = 0.019) and 772 pmol/L (P = 0.007), respectively]. In 31 newly diagnosed GD patients, serum concentrations of IL-6 and sIL-6R during the hyperthyroid phase were elevated, and after therapy with methimazole only, serum sIL-6R concentrations returned to normal (940 vs. 726 pmol/L; P < 0.001) but serum IL-6 did not. Serum sIL-6R concentrations (mean +/- 2 SD) were higher in GD patients with active inflammatory thyroid-associated ophthalmopathy than those in patients with inactive or absent thyroid-associated ophthalmopathy (P < 0.05). In conclusion, we have demonstrated activation of the IL-6 system in GD and, for the first time, have measured and found increased serum sIL-6R concentrations in hyperthyroid GD patients.

Adolescent↗
PubMed1996

Lack of increased serum interleukin-6 and soluble IL-6 receptor concentrations in patients with thyroid diseases following recombinant human interferon alpha therapy.

BACKGROUND: Serum interleukin-6 (IL-6) concentrations are frequently elevated in inflammatory thyroid diseases, such as subacute thyroiditis and amiodarone induced thyroiditis. We and others have recently observed that recombinant interferon-alpha (rIFN-alpha) therapy for chronic, active viral hepatitis and malignant disorders may induce thyroid dysfunction, including thyrotoxicosis secondary to thyroiditis. Serum IL-6 and its soluble receptor (sIL-6R) have been measured for the first time in patients with chronic active hepatitis receiving rIFN-alpha therapy. METHODS: Studies were carried out in 37 patients treated with rIFN-alpha for chronic, active viral hepatitis. Thyroid function tests and serum IL-6 and sIL-6R were measured before and during rIFN-alpha therapy. RESULTS: Six patients developed inflammatory or destructive thyrotoxicosis confirmed by elevated serum free T4 or free T3 concentrations, suppressed serum thyroid-stimulating hormone (TSH) values, and a low thyroid radioactive iodine uptake. Serum IL-6 and sIL-6R concentrations were not elevated in these patients with rIFN-alpha-induced thyroiditis. CONCLUSIONS: These results suggest that serum IL-6 concentrations are not useful in differentiating between inflammatory thyrotoxicosis and hyperthyroidism induced by rIFN-alpha therapy as is the case in amiodarone-induced thyrotoxicosis. It is possible that rIFN-alpha therapy could be associated with an inhibitory effect of rIFN-alpha on the release of IL-6 from damaged thyroid cells and not on the basal secretion of IL-6.

Antigens, CD↗
PubMed1995

Circadian thyrotropin variations are preserved in normal pregnant women.

Serum thyrotropin (TSH) concentration circadian rhythm is abolished in many endocrine and non-endocrine diseases. In the present study we have measured serum TSH concentration over 24 h every 2 h in second and third trimester pregnant women. During the 24-h period, serum free thyroxine and free triiodothyronine concentrations did not change significantly. In contrast, serum TSH concentrations demonstrated significant circadian variations both in the second and third trimester pregnant women (p < 0.02 and p < 0.005, respectively). In summary, second and third trimester pregnancy is associated with a normal circadian TSH rhythm.

Adult↗
PubMed1994

Thyroid ultrasonography in patients with a previous episode of amiodarone induced thyrotoxicosis.

Amiodarone induced thyrotoxicosis (AIT) occurs most frequently in euthyroid patients with nodular goiter or Graves' disease due to release of iodine from this iodine rich drug. However, some cases of AIT have been attributed to an inflammatory process of the thyroid gland due to amiodarone itself. We have studied the echographic pattern of the thyroid in 11 euthyroid patients who had an episode of AIT 32.4 +/- 3.6 months earlier due to amiodarone induced thyroiditis. There was a significant increase in dyshomogeneous echo patterns and hyperechogenecity which suggests fibrotic lesions. These findings were similar to those observed in 10 euthyroid patients who 77 +/- 12 months earlier had an episode of subacute thyroiditis (SAT). Thyroid volumes of control subjects and patients with a history of AIT and SAT were 10.9 +/- 1.4, 8.7 +/- 1.4 and 9.8 +/- 1.7, in the order. These values were not significantly different. These echographic findings, normal serum thyroid hormone and TSH concentrations and the absence of circulating antithyroid peroxidase antibodies suggest that underlying thyroid autonomy and Graves' disease were not the cause of the previous episode of AIT. The presence of hyperechogenic and dyshomogeneous patterns appears the result of the healing of the inflammatory AIT process.

Adult↗
PubMed1994

The iodine perchlorate discharge test before and after one year of methimazole treatment of hyperthyroid Graves' disease.

We have recently reported that many euthyroid patients with a history of Graves' disease treated years earlier with methimazole (MMI) have a positive iodide (500 micrograms)-perchlorate discharge test (I-ClO4 test), suggesting a permanent thyroid iodide organification defect. We now report the results of the I-ClO4 test in patients with hyperthyroid Graves' disease before beginning a 1-yr course of MMI therapy and 40 days after MMI was discontinued. Twenty-nine patients (25 women and 4 men; mean age, 38 +/- 1.7 yr) with their first episode of hyperthyroid Graves' disease were studied. Before MMI therapy, I-ClO4 tests were carried out, and serum T4, T3, and TSH were measured to confirm the diagnosis of hyperthyroidism. A positive I-ClO4 test is defined as more than 15% 131I discharged from the thyroid 1 h after the administration of 1 g KClO4. Patients were then treated with 20 mg MMI for the first 2 months and variable doses thereafter for the next 10 months to maintain euthyroidism. Serum T4, T3, and TSH were measured monthly. Forty days after MMI was discontinued, I-ClO4 tests were repeated, and serum T4, T3, and TSH were measured every 2 months thereafter. Before MMI treatment, the I-ClO4 test was positive in 20 of 29 patients (69%) and negative in 9. The favorable responses (normal serum T4 and T3 values) to MMI therapy were similar in both groups. We have thus far studied 16 patients after MMI was discontinued and 9 of 12 patients (75%) with a negative I-ClO4 test after MMI therapy, and 1 of 4 patients (25%) with a positive test remained in remission for a mean of 7 months. We conclude that the I-ClO4 test is frequently positive in patients with untreated hyperthyroid Graves' disease, suggesting either an inability to organify the increased iodide concentrated by the hyperfunctioning gland or the concomitant presence of Hashimoto's thyroiditis, which almost always is associated with a positive I-ClO4 test. The former hypothesis is more likely, because many patients with a positive I-ClO4 test before MMI therapy had a negative test after MMI was discontinued.

Adult↗
PubMed1994

Echographic diagnosis of pretibial myxedema in patients with autoimmune thyroid disease.

In the present study we have evaluated the use of pretibial ultrasound for the diagnosis of pretibial myxedema (PTM). We studied 76 patients, 58 with Graves' disease, 13 with Hashimoto's thyroiditis and five with idiopathic hypothyroidism. Thirty-two normal subjects were also studied as controls. Sixty-four patients had associated ophthalmopathy. The ultrasound scanner was equipped with 10- and 13-MHz probes. Punch biopsies were carried out in 11 patients and tissue sections examined on a light microscope. On clinical examination 21 patients (28%) had suspected PTM. By ultrasound, we measured the thickness of dermis and subcutaneous tissue (D1) and that including only deeper dermis (D2) in normal subjects to define the echographic parameters of normal pretibial skin. We then found increased skin thickness in 25 patients (33%), with mean D1 and D2 values significantly higher than those measured in controls (p < 0.00001). The echographic study was positive in 20 patients with ophthalmopathy (31%). Ultrasound showed increased skin thickness in 16 of 21 patients (76%) with clinically suspected PTM. Histopathological findings confirmed the presence of PTM in all the patients who underwent pretibial skin biopsy. We believe that the measurement of pretibial skin thickness by ultrasound may be useful for revealing the presence of PTM.

Adult↗