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Biomedical subjects

E Gardini

Publications and source records attributed to E Gardini.

At least 19 recordsLinked to original sources
PubMed2005

Specific properties and effect of perindopril in controlling the renin-angiotensin system.

Perindopril is a long-acting, once-daily lipophilic angiotensin-converting enzyme inhibitor with high tissue angiotensin-converting enzyme affinity, lowering angiotensin II and potentiating bradykinin. Its efficacy, safety, and tolerability are well established in the treatment of hypertension and heart failure. Moreover, large morbidity-mortality trials, such as the EUropean trial on Reduction Of cardiac events with Perindopril in stable coronary Artery disease (EUROPA) and Perindopril pROtection aGainst REcurrent Stroke Study (PROGRESS), have shown that antihypertensive treatment with perindopril reduces and prevents cardiovascular disease in a large range of patients with vascular diseases, whether or not they are hypertensive. Thus, the outcomes of these and other trials support the concept of cardiovascular protective properties of angiotensin-converting enzyme inhibition with perindopril in addition to the obvious blood-pressure-lowering effect. Considering its properties and the clinical evidence on efficacy and tolerability that has been gathered, perindopril fulfils the criteria of the latest guidelines for hypertension and cardiovascular disease management and should therefore be considered as a first-line antihypertensive agent, forming a consistent part of the comprehensive strategy against hypertension and related cardiovascular complications.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2003

Effect of Italy's motorcycle helmet law on traumatic brain injuries.

OBJECTIVES: To evaluate the impact of a revised Italian motorcycle-moped-scooter helmet law on crash brain injuries. DESIGN: A pre-post law evaluation of helmet use and traumatic brain injury (TBI) occurrence from 1999 to 2001. SETTING: Romagna region, northeastern Italy, with a 2000 resident population of 983 534 persons. PARTICIPANTS: Motorcycle-moped rider survey for helmet use compliance and all residents in the region admitted to the Division of Neurosurgery of the Maurizio Bufalini Hospital in Cesena, Italy for TBI. OUTCOME MEASURES: Helmet use compliance and change in TBI admissions and type(s) of brain lesions. RESULTS: Helmet use increased from an average of less than 20% to over 96%. A comparison of TBI incidence in the Romagna region shows that there was no significant variation before and after introduction of the revised helmet law, except for TBI admissions for motorcycle-moped crashes where a 66% decrease was observed. In the same area TBI admissions by age group showed that motorcycle mopeds riders aged 14-60 years sustained significantly fewer TBIs. The rate of TBI admissions to neurosurgery decreased by over 31% and epidural hematomas almost completely disappeared in crash injured moped riders. CONCLUSIONS: The revised Italian mandatory helmet law, with police enforcement, is an effective measure for TBI prevention at all ages.

Accidents, Traffic↗
PubMed2002

Regional brain injury epidemiology as the basis for planning brain injury treatment. The Romagna (Italy) experience.

AIM: Neurosurgical services for traumatic brain injury (TBI) should be based upon the understanding of the epidemiology of TBI in the region as well as the clinical parameters. Our objective was to measure incidence and epidemiologic factors associated with TBI in the Romagna region of Northeastern Italy and correlate those parameters with neurosurgical imaging and related clinical features. METHODS: Guidelines for brain injury management in our region were derived following meetings of all physicians involved in the treatment of brain injury. An epidemiologic study was undertaken in 1998. The study population was all patients admitted for hospital care in the Region following a TBI with a discharge diagnosis of pertinent International Classification Disease, 9(th) revision, codes. Data on the extent, diagnoses, severity, external causes and hospital course were abstracted from the hospital record and computer entered for analyses. RESULTS: Using data for the population of Romagna of about 1000000 persons we identified, in the full year 1998, 2430 TBI patients or an incidence rate of 250 per 100000 resident population. There were, in addition, 460 nonresident patients who were admitted in the region. External causes of injury were generally similar to reports from other places in Western Europe, with the exception of a very low frequency of cases stemming from violence. Age specific incidence rates were highest among young children, persons aged 15-24, and those aged 65 and older. Computerized tomography scans were given to 1732 patients and intracranial traumatic lesions were identified in 497 (28.6%) patients or a rate of 38 /100000. We performed 128 craniotomies, an incidence rate of 11/100000. The case fatality rate (CFR) was 2.8% among admitted patients with the highest rate among those aged 75 or older. CONCLUSION: Incidence of TBI in Italy is similar to other published European series. The number of minor brain injuries admitted for hospital care remains high and can be significantly reduced with better use of CT scans in adults whenever possible. The workload for a neurosurgical unit servicing a population of 1 million is limited and does not justify the opening of new units for trauma care or the use of craniotomies outside the Neurosurgical Unit.

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↗
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↗
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↗
PubMed1993

Thyrotoxicosis followed by hypothyroidism in patients treated with amiodarone. A possible consequence of a destructive process in the thyroid.

Amiodarone is an iodine-rich drug used in the treatment of resistant cardiac arrhythmias. Amiodarone-induced thyrotoxicosis (AIT) is well recognized and is generally believed to be due to the excess iodine released from the metabolism of the drug, although amiodarone-associated thyroiditis has occasionally been observed. We report the clinical, laboratory, and therapeutic course of nine patients with AIT. The thyrotoxic phase was often followed by mild hypothyroidism during and after antithyroid drug or corticosteroid therapy. The thyroid was tender to palpation in two patients and a fine-needle aspiration biopsy of the thyroid revealed changes consistent with thyroiditis in three patients who underwent biopsy. These findings strongly suggest that the etiology of AIT, at least in some patients, is due, in part, to drug-induced inflammatory changes in the thyroid, as has been reported to occur in lung, bone marrow, and testes. Thus, the AIT may be due to excess iodine, drug-induced thyroiditis, or a combination of the two. The favorable response of AIT to corticosteroids in occasional patients previously reported also suggests that acute thyroiditis was probably present.

Adult↗
PubMed1993

Sodium ipodate and methimazole in the long-term treatment of hyperthyroid Graves' disease.

A prospective study was conducted to evaluate the effect of prolonged treatment of hyperthryoid Graves' disease with methimazole (MMI) for 12 months or Na ipodate for only 6.6 +/- 1.1 months, since the drug had to be discontinued because of persistent or recurrent hyperthyroidism during treatment. The eight patients who were treated with MMI alone for 12 months became euthyroid, and seven remained in remission for at least 6 months after MMI was discontinued. In contrast, only two of 10 patients treated with Na ipodate alone became euthyroid and remained so during therapy. No ipodate was discontinued in the eight patients who did not respond, and they were then treated with MMI. One patient had recurrent hyperthyrodism after NA ipodate was discontinued, and she was then treated with MMI. MMI was efficacious in treating these nine patients, and all patients were euthyroid by the third month of MMI administration. Five of these nine patients remained euthyroid for at least 6 months after MMI was discontinued, a remission rate that was not significantly different from that observed in the eight patients treated only and initially with MMI (Fisher's Exact Test). There was no significant change in serum thyroid peroxidase antibodies during treatment with MMI alone, Na ipodate alone, or Na ipodate followed by MMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Effects of chronic iodine administration on thyroid status in euthyroid subjects previously treated with antithyroid drugs for Graves' hyperthyroidism.

In view of the adverse effects of the administration of pharmacological quantities of iodine to euthyroid patients with a history of a wide variety of thyroid disorders, it has been suggested that iodine-containing medications and radioopaque dyes containing iodine should be avoided, if possible, in patients with underlying thyroid disease. We have now prospectively studied the effects of pharmacological doses of a saturated solution of potassium iodide (SSKI) on thyroid function in euthyroid patients with a previous history of hyperthyroid Graves' disease successfully treated with antithyroid drugs. Ten euthyroid women (mean age, 56 yr) who had hyperthyroid Graves' disease successfully treated with methimazole 36.4 +/- 4.7 months earlier were evaluated before, during, and after the administration of 10 drops SSKI daily for 90 days. The following thyroid function tests were obtained: serum T4, T3, TSH, TSH receptor antibody (TSH-RAb), and antithyroid peroxidase antibody (AbTPO) concentrations; TRH tests; and iodine perchlorate discharge tests. Serum T4, T3, basal and TRH-stimulated TSH, and TSH-RAb values were normal before SSKI administration, but serum AbTPO levels were markedly positive in 7 and iodine perchlorate discharge tests were positive in 4 of these 10 women. During SSKI administration, basal and TRH-stimulated serum TSH values increased above normal in 2 women with normal serum T4 and T3 concentrations; thyroid hormone values and TRH tests were normal in the other 8 patients and similar to values observed in 4 euthyroid women without a history of thyroid disease given SSKI. Serum AbTPO increased slightly, but significantly, during SSKI administration in the 7 women with positive values at baseline (P < 0.05). TSH-RAb remained undetectable. After SSKI withdrawal, the 10 women were reevaluated 60 and 120 days later. Two women developed a blunted TSH response to TRH, but normal serum T4 and T3 concentrations, and 2 women developed overt hyperthyroidism, with undetectable basal and TRH-stimulated serum TSH and elevated serum T4 and T3 concentrations, requiring methimazole therapy. All values in the remaining 6 women were similar to those present before SSKI administration. These results suggest that some euthyroid patients with a history of antithyroid drug therapy for Graves' disease may develop thyroid dysfunction during and after excess iodine administration. The development of subclinical hypothyroidism during SSKI administration was not clinically important, but the occurrence of overt hyperthyroidism after SSKI was discontinued did require antithyroid drug therapy. It is advisable, therefore, to avoid iodine-containing substances in euthyroid patients with a history of antithyroid drug therapy for Graves' disease.

Antithyroid Agents↗
PubMed1992

Subclinical hypothyroidism, overt thyrotoxicosis and subclinical hypothyroidism: the subsequent phases of thyroid function in a patient chronically treated with amiodarone.

In a patient chronically treated with amiodarone, subclinical iodine-induced hypothyroidism occurred as a result of excess iodine released from the amiodarone molecule. The patient was maintained on amiodarone and developed thyrotoxicosis as a result of a destructive process into the thyroid follicles. Amiodarone was withdrawn and methylprednisolone and methimazole treatment was started with resolution of the thyrotoxic phase. Months later, off therapy, the patient developed subclinical hypothyroidism. This is the first description of hypo- and hyperthyroidism in the same patient caused by amiodarone therapy. This unusual observation suggests that patients treated with amiodarone are at risk to develop hyperthyroidism even if they show laboratory findings consistent with hypothyroidism.

Amiodarone↗
PubMed1992

Iodine-induced subclinical hypothyroidism in euthyroid subjects with a previous episode of amiodarone-induced thyrotoxicosis.

Amiodarone-induced thyrotoxicosis (AIT) occurs most frequently in patients with underlying thyroid disease and is generally believed to be due to the iodine contamination of amiodarone and iodine released by the metabolism of the drug. We and others have suggested that the thyrotoxicosis may also be secondary to amiodarone-induced thyroiditis. To further determine the etiology of AIT, we administered large doses of iodides [10 drops saturated solution of potassium iodide (SSKI) daily] to 10 euthyroid patients long after an episode of AIT believed to be due at least in part to amiodarone-induced thyroiditis. Six of these 10 patients had an abnormal iodide-perchlorate discharge test before SSKI administration, indicating a subtle defect in the thyroidal organification of iodide. During SSKI administration, 6 patients developed marked iodine-induced basal and/or TRH-stimulated serum TSH elevations, 2 had suppressed basal and TRH-stimulated TSH values, and 2 had normal TSH responses compared to SSKI-treated euthyroid subjects with no history of amiodarone ingestion or thyroid disease. Serum T4 and T3 concentrations remained normal and unchanged during SSKI administration in both the AIT patients and control subjects. These results strongly suggest that excess iodine may not be the cause of the hyperthyroidism associated with amiodarone therapy, especially in those patients with probable amiodarone-induced thyroiditis. Furthermore, like patients with a previous history of subacute thyroiditis and postpartum thyroiditis, the present results suggest that some patients with a previous history of AIT may be at risk to develop hypothyroidism when given excess iodine.

Amiodarone↗
PubMed1992

Prevalence of anti-thyroid peroxidase antibodies in serum in the elderly: comparison with other tests for anti-thyroid antibodies.

Autoimmune thyroid disease, especially chronic thyroiditis, is prevalent in elderly women and is probably the major cause of hypothyroidism in this population. The reported prevalence of chronic thyroiditis is variable, depending on the area of residence and the method(s) used to detect the presence of anti-thyroid antibodies. The recent finding that thyroid peroxidase (TPO) is the antigen for the thyroid anti-microsomal antibody (AbM) has resulted in the development of sensitive radioimmunoassays (RIA) to detect the presence of AbTPO. We have determined the prevalence of AbTPO (by RIA) in sera from 342 elderly subjects, 248 women and 94 men (mean age 80 years) residing in Reggio Emilia, Italy, and compared the results with other methods for detecting anti-thyroid antibodies, including anti-thyroglobulin (AbTg) and AbM measured by passive hemagglutination (PH) of tanned erythrocytes, and AbM measured by RIA. The prevalence of positive AbTPO was 2.3% in the men and 10.2% in the women, only slightly higher than the prevalence of AbM. However, in the antibody-positive sera, the mean value for AbTPO was approximately 20-fold greater than the upper limit of the normal range, whereas the mean value for AbM was only threefold greater. The prevalence of positive titers for AbM and AbTg measured by PH was far lower, 1.2% and 3.2%, respectively, and those sera weakly positive for AbM and AbTg by PH were strongly positive for AbTPO by RIA. AbTPO RIA may be more useful than AbM and AbTg hemagglutination and AbM RIA for detecting the presence of autoimmune thyroid disease.

Aged↗