סלניום והשימוטו

שלום לרופא, קראתי מאמר המתאר מחקר השפעת סלניום על עצירת התהליך האוטואימוני במחלת השימוטו. מה ידוע על הסלניום, האם הוא עלול להזיק? מה דעתך על המאמר? הנה כתובתו: http://www.endo-society.org/pubrelations/summaries/XXIII_autoimmune.cfm תודה

לנעמה שלום לא ידוע לי על הקשר בין סלניום להשימוטו. אולם להלן כמה כללים חשובים להערכת חומר רפואי באינטרנט: 1. האם בכלל מדובר בחומר רפואי או חומר מדעי פופולרי? 2. האם האתר שבו נכתב החומר רציני ואמין (למשל של איגוד גדול, מסונף לעיתון חשוב)? 3. האם המקור הוא עיתון חשוב ברפואה והאם המחקר עבר ביקורת? 4. האם מדובר על דיווח יד פעמי או על כמה עבודות בנושא? כך ניתן להעריך את החומר הקישור ששתלת לא עולה בברכה ד"ר וינקר

P3-208 SELENIUM SUBSTITUTION REDUCES THYROID PEROXIDASE AUTOANTIBODY CONCENTRATION IN PATIENTS WITH AUTOIMMUNE THYROIDITIS B Gasnier, R Gaertner, M Angstwurm, J Dietrich. Endocrinology, Medizinische Klinik University, Munich, Germany It has previously shown, that selenium deficiency may contribute to the development and the maintenance of autoimmune thyroiditis. In addition, selenium dependent enzymes have several modulatory effects on the immune system. We therefore performed a blinded, placebo controlled prospective study in female patients (n=72, mean age 42y) with autoimmune thyroiditis and TPOAb and/or TgAb above 350 U/ml, measured by an immuno-luminiszenz assay (Byk Sangtec). The primary endpoint of the study was the change in the autoantibody concentration as a marker for the activity of the disease. Patients were randomised into two age and antibody matched groups groups; 36 patients received 200 µg sodium selenite per day for three months, 36 patients received placebo. All patients were substituted with L-thyroxine to maintain TSH within the normal range. TPOAb and TgAb concentrations, thyroid hormone levels as well as ultrasound of the thyroid were monitored. After 3 months, 9 patients in the selenium treated group had completely normalized antibody titers in contrast to 2 patients in the placebo group (chiquadtrat test: p=0.02). Ultrasound of the thyroid showed a normalised echogeneity in these patients. The mean TPOAb concentrations decreased significantly to 51% (paired t-test: p=0.042) in the selenium group versus 90% (p=0.73) in the placebo group. The TgAb concentrations were unchanged in both groups. A subgroup analysis of those patients with TPOAb >1200 U/ml (n=8) revealed a mean 40% reduction in the selenium treated patients compared to a 10% increase in the placebo group. The mean TSH, FT4 and FT3 levels were unchanged in both groups during the study. We conclude from this pilot study, that a selenium substitution with 200 µg sodium selenite may improve the inflammatory activity in patients with autoimmune thyroiditis. Whether this effect is specific for autoimmune thyroiditis or may also be effective in other organ specific autoimmune diseases has to be investigated. Clinical Science Poster: P3: Autoimmune Endocrine Diseases (11:00 AM-12:00 PM and 2:30 PM-3:30 PM) Presentation Date: Friday, June 22, 2001; Time: 11:00 AM; Location: Exhibit Hall -------------------------------------------------------------------------------- AUTOIMMUNE ENDOCRINE DISORDERS P3-208 Lay explanation of abstract: Autoimmune thyroid diseases are very common. About 10 % of females and 2 % of males suffer from this disorder. Until now, there was no possibility to prevent the onset of the disease; it was only possible to treat them symptomatically by giving thyroid hormones, or in case of thyrotoxicosis, by blocking thyroid hormone synthesis. Selenium is a trace element, important for the function of several enzymes that modulate the immune function. It has been shown previously, that in areas with low selenium intake, the prevalence of thyroid autoimmune diseases is more common. Therefore, we investigated whether a supplementation of selenium (200 µg/day) for three months in patients with thyroid autoimmune disease (Hashimotos´ thyroiditis) may change the autoantibody (thyroid peroxidase antibodies) concentrations, which are reflecting the activity of the disease. This selenium supplementation has no side effects, it even has been shown to prevent the development of several cancers and to improve immune function (for review see: M.P. Rayman, The importance of selenium to human health. Lancet Vol. 356, 2000, p. 233). In addition, the selenium supplementation is very cheap. We performed a placebo-controlled prospective study, including 72 age-matched females (mean age 42y) with active autoimmune thyroiditis. Thirty-six of them received sodium selenite, 200 µg orally per day, and 36 received placebo. The patients were informed and agreed to participate in the study. We found that the antibody concentrations significantly decreased to 51% in the treatment group, and 9 patients out of the treatment group were completely normalized in antibody titers and thyroid ultrasound compared to only 2 in the placebo group. This clearly indicates that patients with autoimmune thyroid disease benefit from selenium supplementation. We can suggest, especially during onset of the autoimmune thyroid diseases, that a selenium supplementation prevents progression of the disease. We must further investigate whether other, more severe autoimmune diseases can be influenced or even prevented. Selenium therapy would be a new, cost-effective and safe concept of treatment. Additional background information: The trace element selenium is an essential nutrient of fundamental importance to human health. In the past few years, several studies have shown a hitherto unsuspected role for this element. Selenium has a component of selenoproteins, most of which have important enzymatic functions. Most selenoproteins have an important role in the redox system, and their function is to scavenge free radicals. This function helps to maintain membrane integrity, protects from protacyclin production, and reduces the propagation of further oxidative damage to biomolecules such as lipids, lipoproteins, and DNA. (These biomolecules are associated with increased risk of conditions such as atherosclerosis, cancer and also autoimmune disease.) We were especially interested in the role of selenium in treatment of autoimmune thyroid diseases, because it already has been shown that in endemic selenium deficiency, the prevalence of this disease is increased. We succeeded in demonstrating in a clinical trial that in patients with active autoimmune thyroiditis, supplementation with moderate, low-sodium selenite orally significantly decreases autoantibody concentrations and disease activity. This beneficial effect of selenium has to be studied further in more severe autoimmune diseases. This study has not been funded by the government. We received free medication from: biosyn – Arzneimittel GmbH, 70734 Fellbach, Germany. שלום דר' וינקר, העתקתי את המאמר: -------------------------------------------------------------------------------- AUTOIMMUNE ENDOCRINE DISORDERS P3-211 HIGH PREVALENCE OF AUTOIMMUNE THYROIDITIS IN PATIENTS WITH POLYCYSTIC OVARY (PCO) SYNDROME R Gaertner, N Mehlmauer. Endocrinology, Medizinische Klinik Innenstadt, University, Munich, Germany Females are known to have a 5-10 fold higher incidence of organ specific autoimmune diseases including autoimmune thyroiditis compared to males, suggesting a role of female hormones in the pathogenesis of the disease. During the perimenopause, the incidence of newly developing autoimmune thyroiditis is about twice as high as during normal reproductive life. The low progesterone levels and still elevated estrogen levels may contribute to this increased autoimmune activity. As patients with PCO syndrome also have low progesterone levels due to their anovulatory cycles, we now investigated in a prospective study the incidence of autoimmune thyroiditis in caucasian patients with PCO syndrome. Over a period of 12 months all patients with PCO syndrome (n=58), mean age 25y±8.4 were included in the study. PCO syndrome has been documented by increased LH/FSH ratio >2, elevated plasma testosterone levels, hypertrichosis, oligomenorrhea and polycystic ovaries shown by ultrasound. These patients were tested for TPOAb as well as TgAb concentrations by a commercial test kits (Byk Sangtec). In addition TSH, FT4, FT3 was determined and ultrasound of the thyroid was performed. For control, the incidence of postitive TPOAb and TgAb concentrations (>100 U/ml) in 106 age matched patients was investigated. In the control patients, 10% had positive TPOAb and/or TgAb. In contrast, from the 58 patients with PCO syndrome, 25 (43.1%, p=0.0001) had elevated TPOAb (mean 246±251U/ml and/or TgAb (mean 361±578 U/ml), 20 of them hypoechogeneity in thyroid ultrasound. Eight patients were under L-thyroxine substitution and two patients operated because of Graves disease. Free thyroid hormone levels as well as TSH was normal in all patients. This prospective study clearly demonstrates a 4-fold higher prevalence of thyroid specific antibodies in patients with documented PCO syndrome compared to controls, and 17% of them had clinical autoimmune thyroiditis. This might be due to the impaired progesterone/estrogen levels compared to normal young females and therefore a stimulation of T- and B-lymphocyte activity or due to different genetic background. Clinical Science Poster: P3: Autoimmune Endocrine Diseases (11:00 AM-12:00 PM and 2:30 PM-3:30 PM) Presentation Date: Friday, June 22, 2001; Time: 11:00 AM; Location: Exhibit Hall -------------------------------------------------------------------------------- AUTOIMMUNE ENDOCRINE DISORDERS P3-211 Lay explanation of abstract: Females are known to have a 5-10-fold higher incidence of organ-specific autoimmune diseases including autoimmune thyroiditis compared with males. This higher incidence suggests that female hormones play a role in the pathogenesis of this disease. During perimenopause (time just before menopause), the incidence of newly developing autoimmune thyroiditis is about twice as high as during normal reproductive life. The low progesterone levels and still elevated estrogen levels during this period may contribute to this increased autoimmune activity. Because young females with PCO syndrome (polycystic ovary syndrome) also have low progesterone levels due to their anovulatory (non-ovulating) cycles, we investigated in a prospective study the incidence of autoimmune thyroiditis in Caucasian patients with PCO syndrome. Over a period of 12 months, all patients with PCO syndrome (n=58), mean age 25+8.4y were included in the study. PCO syndrome has been documented by an increased LH/FSH ratio >2, low progesterone and/or elevated plasma testosterone levels, hypertrichosis, oligomenorrhea, and polycystic ovaries shown by ultrasound in most of the patients. All patients were tested for TPOAb as well as TgAb concentrations by commercial test kits (Byk Sangtec). In addition TSH, FT4, FT3 was determined and ultrasound of the thyroid was performed. For control, the incidence of positive TPOAb and TgAb concentrations (>100 U/ml) in 106 age-matched patients was investigated. In the control patients, 10% had positive TPOAb and/or TgAb. In contrast, among the 58 patients with PCO syndrome, 25 (43.1%, p=0.0001) had elevated TPOAb and/or TgAb, 20 of them hypoechogeneity in thyroid ultrasound. Eight patients were under L-thyroxine substitution, and two patients already had had operations because of Graves´ disease. Free thyroid hormone levels as well as TSH was normal in all patients. This prospective study clearly demonstrates a 4-fold higher prevalence of autoimmune thyroiditis in patients with documented PCO syndrome. This might be due to the impaired estrogen/progesterone levels compared to normal young females and therefore a stimulation of T- and B-lymphocyte activity or due to different genetic background. The clinical consequence should be that all patients with PCO syndrome should be tested and followed up for their thyroid function. The result of the study also is of interest because it gives further insight into the pathogenesis of autoimmune diseases. Estrogens, if not counteracted by progesterones, seem to be responsible for the increased activity of the immune system. Therefore, a patient’s genetic disposition for developing autoimmune diseases might propagate the disease. Additional background information: The results of this study have two implications: Clinical: PCO syndrome is a common disease; about 5% of all women are suffering from this disease. We found that about half of these women also have autoimmune thyroiditis, so these patients also have to be tested for thyroid function and vice versa. In addition, progesterone substitution in these patients might be useful in preventing the disease. Pathophysiological: It is known from in vitro studies that estrogens stimulate the immune system, whereas progesterones decrease this activity. Our hypothesis therefore was, that females with a lack of normal progesterone production but normal estrogens might develop a higher incidence of autoimmune diseases. Because patients with PCO syndrome, which is characterized by low progesterone levels, have a 4-fold higher incidence of autoimmune thyroiditis, this seems to support our hypothesis. It also appears that progesterones or derivatives of this hormone with a specific target to immune competent cells are a suitable immunosuppressive agent. This study has not been funded by the government or a company. All work was performed without external financial support. ושוב כתובת המאמר : http://www.endo-society.org/pubrelations/summaries/XXIII_autoimmune.cfm מאמר זה מופיע באתר: http://www.endo-society.org/about/index.cfm עוד לא עיינתי בכל האתר, ואין לי מושג עד כמה המידע שם מהימן או לא. אני מקווה שתצליח להכנס לאתר, ולכתוב לי מהי התרשמותך. המון תודה!