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itemscope="" itemtype=""><span itemprop="title">Polycythemia Vera</span></li> </ul> </div> </div><!-- box-inner-sticky --> <div class="box-left-border-persist"><!-- left sticky box border --></div> <div class="box-right-border-persist"><!-- right sticky box border --></div> </div><!-- box-sticky --> </div> </div> </div> </div><!-- header --><div class="hl" id="hl"> <div class="container c"> <div class="hl-loading-mask"> <div aria-hidden="true" class="hl-loading-mask-spinner hl-icon-spinner spinner--steps"></div> </div> <div class="overlay-simple overlay-sharebar" id="overlaySharebar"> <div class="overlay-content"> </div> <div class="overlay-footer"> <div class="overlay-close">Cancel</div> </div> </div> <header class="hl-title-area"> <h1>Polycythemia Vera</h1> <p class="attribution" id="byline"> Written by Lydia Krause | Published on <meta content="2012-07-16" itemprop="datePublished"/>July 16, 2012<br/>Medically Reviewed by <a href="">George Krucik, MD</a> </p> <div class="hl-widget-sharebar c"></div> <div class="sharebarContainer"><a class="link-sharebar" href="#overlaySharebar" id="sharebarLink" rel="#overlaySharebar"></a></div> </header> <nav class="hl-tab-navigation"> <div class="hl-arrow-tabnav hl-left-arrow-tabnav hl-icon-left-arrow"></div> <div class="hl-lpipe-tabnav"></div> <div class="hl-tabs-tabnav"> <ul> <li><a href="#Overview"> Overview</a></li> <li><a href="#Causes"> Causes</a></li> <li><a href="#Symptoms"> Symptoms</a></li> <li><a href="#Diagnosis"> Diagnosis</a></li> <li><a href="#Treatment"> Treatment</a></li> <li><a href="#Outlook"> Outlook</a></li> </ul></div> <div class="hl-rpipe-tabnav"></div> <div class="hl-arrow-tabnav hl-right-arrow-tabnav hl-icon-right-arrow"></div> </nav> <div class="grid648"> <div class="container-article" itemscope="" itemtype=""> <article class="hl-article-toc"> <h2 class="content_head" id="TOC_TITLE_HDR_1"><a name="Overview"></a>What Is Polycythemia Vera? </h2><div class="content_body" id="TOC_TITLE_1"> <p>Polycythemia vera (PV) is a bone marrow disorder in which the body produces an excessive amount of red blood cells. Red blood cells are responsible for carrying oxygen to all parts of the body.</p><p> Blood is carried throughout the body by a system of veins and <A id="hllink69" class="hllink hllink-auto" href="">arteries</A>. When too many red blood cells exist, they begin to form clots within the blood vessels. Clots are formed by large amounts of cells grouped together.</p><p> Many people with this condition easily ignore early symptoms such as fatigue. Untreated PV, on the other hand, cannot be ignored, as serious symptoms will usually begin to develop due to the blood clots. The clots block blood from reaching the heart or <A id="hllink116" class="hllink hllink-auto" href="">brain</A>, causing serious damage. </p><p> There is no known cure for PV, so treatment focuses on using medications to prevent serious blood clots. Unfortunately, patients who do not follow treatment have a high likelihood of dying early from clot complications. </p> </div> <h2 class="content_head" id="TOC_TITLE_HDR_2"><a name="Causes"></a>What Causes Polycythemia Vera? </h2> <div class="content_body" id="TOC_TITLE_2"> <p>Polycythemia vera is a rare disorder that occurs more often in men than in women, and rarely in anyone under 40. Polycythemia vera is usually associated with a gene mutation called JAK2V617F. Mutations are changes or damage in the body’s DNA. DNA is responsible for all of your physical characteristics, from eye color to fingerprints. </p><p> The bone marrow production of <A id="hllink30" class="hllink hllink-auto" href="">blood cells</A> is supposed to be tightly regulated. If you have PV, your bone marrow produces too many red blood cells. </p> </div> <h2 class="content_head" id="TOC_TITLE_HDR_3"><a name="Symptoms"></a>What Are the Symptoms of PV? </h2> <div class="content_body" id="TOC_TITLE_3"> <p>Early symptoms of PV are common physical ailments and easily ignored by the patient. However, untreated PV may cause blood clots, which can lead to serious complications. </p><p> Early symptoms of PV include:</p> <ul> <li>fatigue</li> <li>difficulty breathing</li> <li>tingling in the hands and feet</li> </ul> <p>Significant blood clot complications from untreated PV include:</p> <ul> <li>heart attack</li> <li>deep vein thrombosis (DVT)</li> <li>stroke</li> </ul> <p>Doctors may not discover PV until after a fatal complication has occurred. Fatal complications include:</p> <ul> <li>ischemic stroke—a <A id="hllink243" class="hllink hllink-auto" href="">stroke</A> caused by loss of blood supply to the brain </li> <li><A id="hllink252" class="hllink hllink-auto" href="">pulmonary embolism</A>—a blood clot in the <A id="hllink248" class="hllink hllink-auto" href="">lung</A></li> <li>hemorrhagic death—death from <A id="hllink253" class="hllink hllink-auto" href="">bleeding</A>, usually from the <A id="hllink255" class="hllink hllink-auto" href="">stomach</A> or other parts of the digestive tract</li> </ul> </div> <h2 class="content_head" id="TOC_TITLE_HDR_4"><a name="Diagnosis"></a>How Is PV Diagnosed? </h2> <div class="content_body" id="TOC_TITLE_4"> <p>If your doctor suspects that you might have PV, he or she will order a blood test called a complete blood count (CBC). A CBC measures the number of red blood cells, the number of white blood cells, the amount of hemoglobin (a protein that carries oxygen) in the blood, as well as how much space is taken up by red blood cells in the blood. If you have PV, an unusually large percentage of your blood volume will be taken up by red blood cells. </p> </div> <h2 class="content_head" id="TOC_TITLE_HDR_5"><a name="Treatment"></a>How Is PV Treated? </h2> <div class="content_body" id="TOC_TITLE_5"> <p>PV is a chronic illness and cannot be cured. The only way to treat the disease is through management and prevention. Doctors will treat patients differently based upon their risk for blood clots. </p> <h3>Low-Risk Patients</h3> <p>Patients with a low risk for blood clots include:</p> <ul> <li>people under 60 without prior history of blood clots</li> <li>people with low blood pressure and low cholesterol</li> <li>people who do not smoke</li> </ul> <p>Treatments for those at low risk include regular phlebotomy and low-dose aspirin. Phlebotomy is the removal of blood through a <A id="hllink198" class="hllink hllink-auto" href="">vein</A>. Blood is withdrawn daily or almost daily and regular CBCs are run until a decrease in the number of red blood cells is seen. This is basically a wait-and-see approach.</p><p> Your doctor may prescribe low-dose aspirin to thin the blood and prevent blood clots. The low-dose aspirin significantly reduces the risk for <A id="hllink427" class="hllink hllink-auto" href="">heart attacks</A> and stroke. </p> <h3>High-Risk Patients</h3> <p>Factors that increase your risk of developing blood clots include: </p> <ul> <li>a history of prior blood clots</li> <li>increasing age</li> <li>high blood pressure</li> <li>diabetes</li> </ul> <p>High-risk patients may require more specialized treatment, using either hydroxyurea or interferon alpha.</p><p> <strong>Hydroxyurea</strong> suppresses the production of red blood cells. This reduces the risk for clots, but increases the risk of leukemia. </p><p> <strong>Interferon alpha</strong> helps prevent clots but is expensive and has a high risk of fever and flulike side effects. Patients with <A id="hllink477" class="hllink hllink-auto" href="">thyroid</A> and/or mental disorders are to avoid this medication. </p> </div> <h2 class="content_head" id="TOC_TITLE_HDR_6"><a name="Outlook"></a>What Is the Long-Term Outlook for PV? </h2> <div class="content_body" id="TOC_TITLE_6"> <p>PV is a chronic disorder. Treatment works to decrease the amount of red blood cells being produced by the bone marrow and to prevent blood clots from forming. Patients who strictly adhere to treatment may be able to live without complications.</p> </div></article> <div class="span12 box-share-help-feedback"> <div class="span5"> <div class="box-article-helpful"> <div class="box-helpful-question"> Was this article helpful? <span class="helpful-option-yes">Yes</span> <span class="helpful-option-no">No</span> </div> <div class="box-helpful-confirmation"></div> </div> </div> <div class="span3"> <div class="box-link-feedback"> <span class="icon-email"></span> <a class="link-feedback" href="#feedbackOverlay" id="feedbackLink" rel="#feedbackOverlay">Feedback?</a> </div> <div class="overlay-simple overlay-feedback" id="feedbackOverlay"> <div class="overlay-content"> <div class="box-form-feedback" id="feedbackformdiv"> <form action="/v2/widgetemail" id="feedbackform"> <input name="to" type="hidden" value="hrl"></input> <input id="urlfield" name="urlfield" type="hidden" value=""></input> <h2>Send us your feedback</h2> <p class="box-message">We are unable to respond directly to questions, but your feedback is greatly appreciated, and will be taken into account in our ongoing review of our Health Reference Library.<br/></p> <p> <label>Your Name:</label><br/> <input class="field-name" id="nametext" name="nametext" placeholder="Name Here" type="text"></input> <span class="box-msg-error" id="box-msg-name"><span class="icon-error">✖</span> <span id="errorMsgName">Please enter your name</span></span> </p> <p> <label>Your Email:</label><br/> <input class="field-email-address" id="feedbackemail" name="emailaddress" placeholder="" type="email"></input> <span class="box-msg-error" id="box-msg-email"><span class="icon-error">✖</span> <span id="errorMsgEmail">Please enter your email</span></span> </p> <p> <input id="copy" name="copy" type="checkbox"></input> <label>Send me a copy</label> </p> <p class="box-textarea"> <textarea class="field-message" cols="60" id="feedbacktextarea" name="messagetext" rows="4"></textarea> </p> <div class="textarea-char-count" id="charcount">0</div> <p class="box-buttons"> <button class="btn-cancel" name="feedbackcancelbutton" type="button">Cancel</button> <button class="btn-send-msg">Send Message</button> <span class="box-loading"><img alt="" src="/resources/base/images/ajax-loader.gif"/></span> </p> </form> <p class="box-privacy"><span class="icon-lock"></span> Email addresses will not be shared with 3rd parties. See <a href="" target="_blank">privacy policy</a></p> </div> <div class="box-thankyou" id="thankyou"> <h2><span class="icon-green-checkmark"></span> Thank you.</h2> <p>Your message has been sent.</p> </div> <div class="box-submit-error" id="submissionerror"> <h2>We're sorry, an error occurred.</h2> <p>We are unable to collect your feedback at this time. However, your feedback is important to us. Please try again later.</p> </div> </div><div class="overlay-footer"> <div class="overlay-close">Close</div> </div> </div> </div> </div> <div class="row12 hl-article-references"> <div class="span8"> <div class="box-article-source "> <p class="references-title">Article Sources:</p> <div class="basesources"> <ul> <li>Finazzi, G., & Barbui, T. (2007, June 15). How I treat patients with polycythemia vera. <em>BLOOD</em>, <em>109</em>(12), 5104-5111. Retrieved July 17, 2012, from <a href=""></a> </li> <li>Kayrak, M., Acar, K., Gul, E., Abdulhalikov, T., Baglicaklioglu, M., Sonmez, O., Kaya, Z., & Ari, H. (2012). Electrocardiographic findings in patients with polycythemia vera. <em>International Journal of Medical Sciences</em>, <em>9</em>(1), 93-102. Retrieved July 17, 2012, from <a href=""></a> </li> <li>Polycythemia vera. (2011, February 28). <em>PubMed Health</em>. 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Learn more in this slideshow.</div> <div class="content-promotion-link summary-action"> <a href="" title="Numbness, Muscle Pain and Other RA Symptoms"> Read More <span> »</span></a> </div> </div> </div> <div class="content-promotion-story click-link" data="/health-slideshow/common-asthma-triggers-how-to-avoid"> <div class="content-promotion-title">Common Asthma Triggers and How to Avoid Them</div> <div class="content-promotion-image"> <a href="" title="Common Asthma Triggers and How to Avoid Them"><img alt="Common Asthma Triggers and How to Avoid Them" src="/hlcmsresource/images/slideshow/Common-asthma-triggers-how-to-avoid/194x105_Asthma_Triggers_1.jpg"/></a> </div> <div class="content-promotion-text"> <div class="content-promotion-disclaimer">Learn about some of the most common triggers for asthma, as well as measures you can take to minimize your risk of exposure, symptoms, and flares.</div> <div class="content-promotion-link summary-action"> <a href="" title="Common Asthma Triggers and How to Avoid Them"> Read More <span> »</span></a> </div> </div> </div> <div class="content-promotion-story click-link" data="/health-slideshow/top-iphone-android-multiple-sclerosis-apps"> <div class="content-promotion-title">The Best Multiple Sclerosis iPhone and Android Apps of the Year</div> <div class="content-promotion-image"> <a href="" title="The Best Multiple Sclerosis iPhone and Android Apps of the Year"><img alt="The Best Multiple Sclerosis iPhone and Android Apps of the Year" src="/hlcmsresource/images/slideshow/best-ms-apps/194x105_Best_MS_Apps_2014.jpg"/></a> </div> <div class="content-promotion-text"> <div class="content-promotion-disclaimer">These best multiple sclerosis apps provide helpful information and tools to keep track of your symptoms, including medication reminders.</div> <div class="content-promotion-link summary-action"> <a href="" title="The Best Multiple Sclerosis iPhone and Android Apps of the Year"> Read More <span> »</span></a> </div> </div> </div> </div> </div> <!--hl-linking-ignore-end--> </div> </div></div> <div class="grid300"> <div class="mr1block c"> <div class="box-ad-mr1"> <div class="ads-margin ads-box-header">Advertisement</div> <div class="ads-medium-rect"> <div id="DFPAD_MR" style="position:relative"> <iframe frameborder="0" id="ifrmmr1" name="ifrmmr1" scrolling="no" src="" style="width:300px;height:250px;margin-top:0px;margin-left:0;border:0;overflow:hidden;position:absolute;top:0;left:0"></iframe> </div> </div> </div> </div> <div class="mr2block c"> <div class="ads-margin ads-box-header">Advertisement</div> <div class="ads-box" id="ad-anchor"> <div class="ads-medium-rect ads-margin"> <iframe class="ifrmmr2" frameborder="0" id="ifrmmr2" name="ifrmmr2" scrolling="no" src=""></iframe> </div> </div> </div> </div> </div> </div> <!-- Healthline Pencil Ad: hidePencilAdv NOT empty AND false --> <div class="ad-pb"> <div class="ads-box-header-pb" id="ads-box-header-pb">Advertisement</div> <div class="dfp-pb-wrapper"> <div class="dfp-pb"> <div id="DFPAD_PB" style="position:relative"> <iframe frameborder="0" id="ifrmpb" name="ifrmpb" scrolling="no" src="" style="width:978px;height:25px;margin:0;border:0;overflow:hidden;position:absolute;top:0;left:0"></iframe> </div> </div> </div> </div> <!-- Begin comScore Tag --> <script> document.write(unescape("%3Cscript src='" + (document.location.protocol == "https:" ? 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Healthline is for informational purposes and should not be considered medical advice, diagnosis or treatment recommendations. <a href="" rel="nofollow">Terms of Use</a> | <a href="" rel="nofollow">Privacy Policy</a></p></div> </div> </div> </div> </div> </div> <!-- hl-main-content --> <!-- hl-page --> <!-- Synvisc_HL_Survey --> <script type="text/javascript">// <![CDATA[ var ord = window.ord || Math.floor(Math.random() * 1e16); document.write('<script type="text/javascript" src=";sz=1x1;ord=' + ord + '?"><\/script>'); // ]]></script> <noscript> <a href=";sz=1x1;ord=[timestamp]?"> <img height="1" src=";sz=1x1;ord=[timestamp]?" width="1"/> </a> </noscript> <!-- Comscore Survey Script --> <script src="//"></script> <script> // are these global variables needed? // do they need to be global variables? microsoft_adunit_keywordhints = "Polycythemia Vera"; u_microsoft_adunit_channelids = ""; microsoft_adunit_channelids = ""; // is this input field needed? document.write('<input id="msftChannelIds1" name="msftChannelIds1" type="hidden" value="'+microsoft_adunit_channelids+'">'); require(["jquery","base/dfpmanager","base/responsive-ads","matchmedia"],function($,AppDfpmanager,AppResponsiveAds){ // default - show LB ad on page load var isAdOnPageLoad = true; var breakpointsToHideAd = []; var breakpointsToHideAdByPageType = []; breakpointsToHideAdByPageType = ['768','600']; isAdOnPageLoad = AppResponsiveAds.getShowAdOnPageLoad("LB",breakpointsToHideAd,breakpointsToHideAdByPageType); var cfgDfpManager = { isAdOnPageLoad: isAdOnPageLoad, adshost : '', logged_in : 'false', dfpAdSite : '', btk1 : '', btk2 : '', kw : 'otherbloodcelldisorders,polycythemia_vera,4806354', k1 : 'otherbloodcelldisorders', k2 : 'bloodcelldisorders', k3 : 'health', pos : 'lb', ugc : 'false', ac : '', uac : '', akh : 'Polycythemia Vera', aks : '5000', env : '', msiteID : '', adTagPageUrl : encodeURIComponent('/health/polycythemia-vera'), partner : 'www', pg_dart_site : '', pg_dart_zone : 'otherbloodcelldisorders', pg_k2 : 'bloodcelldisorders', pHLID : '4806354', HLID : '4806354', visit_type : 'HCviewer', yeildex : 'true', targetsrc : '' }; AppDfpmanager.lbIframeInit(cfgDfpManager); }); </script> <script> require(["healthline/header"], function(header){ header.setOptions({ isNews: false, isNewsChecked: false }); }); </script> <script> require(["jquery"], function( $ ){ $(document).ready(function() { $( '#box-health-tools' ).on( 'click', 'a', function(){ if( $( this ).text() == 'Doctor Search' ){ _gaq.push( [ 'hl._link', $( this ).attr( 'href' ) ] ); return !window._gat; } return true; }); }); }); </script> <script> require([ "base/loading-mask" ], function( WidgetLoadingMask ){ WidgetLoadingMask.initialize(); }); </script> <script> require([ 'jquery', 'base/util/sharebar' ],function( $ ) { // todo: need to // - fix bug regarding HTML encoding, apostrophes, double quotes and question mark characters with page title data that is passed to facebook via the name parameter // - in FE, decode any HTML encoding in title data // - in FE, escape the page title data // - verify four uses cases: // - html encoding // - single quote // - double quote // - question mark $(document).ready(function() { var page_image; var customWidgets = new Array(); var stringWidget = "facebook,twitter,googleplus,email,print"; var isPrintFriendly = false; if( (typeof stringWidget) == "string" && stringWidget.length > 0) { customWidgets = stringWidget.split(','); } else{ customWidgets = stringWidget; } ShareBar.init({ iconSize: "medium", widgets: customWidgets, containerId: ".hl-widget-sharebar", facebookApiKey: "239371929577489", facebookRedirect: "", page_url: HLSHAREBAR.page_url, page_title: HLSHAREBAR.page_title, isPrintFriendly: isPrintFriendly, page_description: (HLSHAREBAR.page_description ? HLSHAREBAR.page_description : ''), email_page_url: HLSHAREBAR.email_page_url, email_page_title: HLSHAREBAR.email_page_title //page_image: page_image }); }); }); </script> <script> require([ "base/title-area", "base/overlay" ], function( WidgetTitleArea, AppOverlay ){ WidgetTitleArea.initialize(); var onBeforeLoadFunc = function() { $('.hl-main-content').css('z-index','auto'); }; var cfgOverlay = { maskColor: '#555555', maskLoadSpeed: 200, maskOpacity: 0.5, maskZindex: 9999999, top: "center", left: "center", close: ".overlay-close", onBeforeLoad: onBeforeLoadFunc }; AppOverlay.initialize( cfgOverlay ); }); require([ "base/rwd/title-area" ], function( WidgetTitleAreaResponsive ){ WidgetTitleAreaResponsive.initialize({ pubDateExists: true, medReviewDateExists: false, medReviewedBy: '', reviewDate: '' }); }); </script> <script> require([ "base/tab-navigation" ], function( WidgetTabNavigation ){ var promoTitle = "", partnerId = 28, adRefresh = false, cfg, sponsorDisclaimerOffset = 0, mr1RefreshTime = 4000; promoTitle = "More on Healthline"; partnerId = 28; adRefresh = true; if ( $( ".hl-sponsor-disclaimer" ).length ) { sponsorDisclaimerOffset = 78; } cfg = { promoTitle: promoTitle, partnerId: partnerId, contentPromoOffset: 70, sponsorDisclaimerOffset: sponsorDisclaimerOffset, adRefresh: adRefresh, mr1RefreshTime: mr1RefreshTime } WidgetTabNavigation.initialize(cfg); }); </script> <script> require(["jquery","base/overlay","base/feedback"],function($,AppOverlay){ var onBeforeLoadFunc = function() { $('.hl-main-content').css('z-index','auto'); $('#feedbackformdiv').show(); }; var cfgOverlay = { selectorValue: 'feedbackOverlay', maskColor: '#555555', maskLoadSpeed: 200, maskOpacity: 0.5, maskZindex: 9999999, top: "center", left: "center", close: ".overlay-close", onBeforeLoad: onBeforeLoadFunc }; AppOverlay.initialize(cfgOverlay); }); </script> <script> require(['jquery', 'base/content-promotion-widget'],function($, AppContentPromotion){ var config = { contentPromotionParam: '', platformPageType: 'articleTOC' }; AppContentPromotion.initialize(config); }); </script> <script> u_microsoft_adunit_channelids = "" microsoft_adunit_channelids = ""; document.write('<input id="msftChannelIds1" name="msftChannelIds1" type="hidden" value="'+microsoft_adunit_channelids+'">'); require(['jquery',"base/dfpmanager","base/responsive-ads","matchmedia"],function($,AppDfpmanager,AppResponsiveAds){ // determine if mr1 ad is shown on page load var isAdOnPageLoad = true; var breakpointsToHideAd = []; var breakpointsToHideAdByPageType = []; breakpointsToHideAdByPageType = ['768','600','480','320']; isAdOnPageLoad = AppResponsiveAds.getShowAdOnPageLoad("MR1",breakpointsToHideAd,breakpointsToHideAdByPageType); var cfgDfpManager = { isAdOnPageLoad: isAdOnPageLoad, adshost : '', adSize: '300x250', dfpAdSite : '', btk1 : '', btk2 : '', kw : 'otherbloodcelldisorders,polycythemia_vera,4806354', k1 : 'otherbloodcelldisorders', k2 : 'bloodcelldisorders', k3 : 'health', pos : 'mr1', ugc : 'false', ac : '', uac : '', akh : 'Polycythemia Vera', aks : '5000', env : '', msiteID : '', adTagPageUrl : encodeURIComponent('/health/polycythemia-vera'), yeildex : 'true', targetsrc : '' }; var mr1timeout = setTimeout(function() { AppDfpmanager.mr1IframeInit(cfgDfpManager); }, 300); }); </script> <script> require(["jquery","base/dfpmanager","base/responsive-ads","matchmedia"],function($,AppDfpmanager,AppResponsiveAds){ $(function() { // determine if mr2 ad is shown on page load var isAdOnPageLoad = true; var breakpointsToHideAd = []; var breakpointsToHideAdByPageType = []; breakpointsToHideAd = ['997','768','600','480','320']; var isAdOnPageLoad = AppResponsiveAds.getShowAdOnPageLoad("MR2",breakpointsToHideAd,breakpointsToHideAdByPageType); var cfgDfpManager = { isAdOnPageLoad: isAdOnPageLoad, adshost : '', dfpAdSite : '', btk1 : '', btk2 : '', kw : 'otherbloodcelldisorders,polycythemia_vera,4806354', k1 : 'otherbloodcelldisorders', k2 : 'bloodcelldisorders', k3 : 'health', pos : 'mr2', ugc : 'false', ac : '', uac : '', env : '', msiteID : '', adTagPageUrl : encodeURIComponent('/health/polycythemia-vera'), yeildex : 'true' , targetsrc : '' }; AppDfpmanager.mr2IframeInit(cfgDfpManager); }); // dom ready }); </script> <script> var rightRailNotSticky = false; rightRailNotSticky = false; require([ "base/article-toc" ], function( AppArticleToc ){ AppArticleToc.initialize({ isArticleHelpful: false, partnerId: 28, titleAreaTop: '60px', tabNavigationTop: '85px', rightRailNotSticky: rightRailNotSticky }); }); var isMsiteId = false; require([ "base/rwd/article-toc" ], function( AppArticleTocRwd ){ AppArticleTocRwd.initialize({ isMsiteId: isMsiteId, adRBTimeDelay: 300 }); }); require([ "base/rwd/sharebar-mobile" ], function( AppSharebarMobile ){ AppSharebarMobile.initialize(); }); require( ['jquery', 'matchmedia'], function( $ ) { $(function() { if( matchMedia('only screen and (max-width: 599px)').matches ) { var contentSectionsLength = $('.content_head').length; //add sharethrough ad div where the ad will be populated via the sharethrough javascript included above //after first section $( '<div data-str-native-key="47d89e59" style="display: none;"></div>' ).insertAfter( $( '#TOC_TITLE_1' ) ); //after last section $( '<div data-str-native-key="f66f2fdd" style="display: none;"></div>' ).insertAfter( $( '#TOC_TITLE_' + contentSectionsLength ) ); // if sharethrough library loaded, then boot up if( typeof STR === 'object' ) { STR.Tag.boot(); } } // test if phone breakpoint }); // dom ready }); // require call </script> <script> require(['jquery',"base/dfpmanager","base/responsive-ads","matchmedia"],function($,AppDfpmanager,AppResponsiveAds){ $(function() { // determine if pb ad is shown on page load var isAdOnPageLoad = true; var breakpointsToHideAd = []; var breakpointsToHideAdByPageType = []; breakpointsToHideAd = ['600','480','320']; var isAdOnPageLoad = AppResponsiveAds.getShowAdOnPageLoad("PB",breakpointsToHideAd,breakpointsToHideAdByPageType); var cfgDfpManager = { isAdOnPageLoad: isAdOnPageLoad, adshost : '', logged_in : 'false', dfpAdSite : '', btk1 : '', btk2 : '', kw : 'otherbloodcelldisorders,polycythemia_vera,4806354', k1 : 'otherbloodcelldisorders', k2 : 'bloodcelldisorders', k3 : 'health', pos : 'lb', ugc : 'false', ac : '', uac : '', akh : '', aks : '5000', env : '', msiteID : '', adTagPageUrl : encodeURIComponent('/health/polycythemia-vera'), partner : 'healthline', pg_dart_site : '', pg_dart_zone : 'otherbloodcelldisorders', pg_k2 : 'bloodcelldisorders', pHLID : '4806354', HLID : '4806354', visit_type : 'HCviewer', yeildex : 'true', targetsrc : '' }; var pbtimeout = setTimeout(function() { AppDfpmanager.pbIframeInit(cfgDfpManager); }, 300); }); // dom ready }); </script> <script> var HL_adBlankMonitor = function(cfg) { if(cfg.adBlankCodes.length > 0) { for(var i = 0; i < cfg.adBlankCodes.length; i++) { if (typeof HL_ga_sendTrackEvent === 'function') { HL_ga_sendTrackEvent({ gaEventCategory : 'Ad Display', gaEventAction : 'Blank Ad', gaEventLabel : 'adBlankCode=' + cfg.adBlankCodes[i] + '&adspot=' + cfg.adPosition + '&pageUrl=' + window.location.pathname }); } } } }; </script> <script> require([ 'healthline/newsletter-signup' ], function( newsletterSignup ){ newsletterSignup.setConfig({ newsletterHost: '' }); }); </script> <script> /* load module */ require(["healthline/footer"]); </script>