nih-gov/medlineplus.gov/ency/article/000079.htm
2025-02-26 13:17:41 -05:00

299 lines
No EOL
33 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html lang="en" id="article" class="nojs us" data-root="//medlineplus.gov" itemid="https://medlineplus.gov/ency/article/000079.htm" itemtype="http://schema.org/MedicalWebPage" itemscope="">
<head>
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"/>
<meta http-equiv="window-target" content="_top"/>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
<meta charset="utf-8"/>
<meta property="fb:app_id" content="1042245625821448"/>
<meta name="expires" content="Wed, 05 02 2025"/>
<meta name="ac-dictionary" content="medlineplus-ac-dictionary"/>
<link rel="shortcut icon" href="https://medlineplus.gov/images/favicon.ico" type="image/x-icon"/>
<link rel="apple-touch-icon" href="//medlineplus.gov/images/touch-icon.png"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<link rel="stylesheet" href="https://medlineplus.gov/css/common_new.css?04272023"/>
<!--[if IE 8]> <link rel="stylesheet" href="https://medlineplus.gov/css/ie8/common.css"><![endif]-->
<link rel="stylesheet" href="https://medlineplus.gov/uswds/css/uswds_styles.css"/>
<link rel="stylesheet" href="https://medlineplus.gov/css/ency/ency2.css?07162024"/>
<script type="text/javascript">document.querySelector("html").className = document.querySelector("html").className.replace(/nojs[\s]*/g, '');</script>
<script src="https://medlineplus.gov/uswds/js/uswds-init.min.js" type="text/javascript">
</script>
<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&amp;l='+l:'';j.async=true;j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-MMVM77');</script>
<link rel="canonical" href="https://medlineplus.gov/ency/article/000079.htm" itemprop="url"/>
<link rel="alternative" hreflang="es" href="https://medlineplus.gov/spanish/ency/article/000079.htm"/>
<link rel="alternative" hreflang="en" href="https://medlineplus.gov/ency/article/000079.htm"/><meta property="og:title" content="Atypical pneumonia: MedlinePlus Medical Encyclopedia"/><meta property="og:url" content="https://medlineplus.gov/ency/article/000079.htm"/><meta property="twitter:title" content="Atypical pneumonia: MedlinePlus Medical Encyclopedia"/><meta name="twitter:card" content="summary_large_image"/><meta name="description" content="Pneumonia is inflamed or swollen lung tissue due to infection with a germ."/><meta itemprop="description" name="description" content="Pneumonia is inflamed or swollen lung tissue due to infection with a germ."/><meta property="og:description" content="Pneumonia is inflamed or swollen lung tissue due to infection with a germ."/><meta property="twitter:description" content="Pneumonia is inflamed or swollen lung tissue due to infection with a germ."/><meta property="og:image" content="https://medlineplus.gov/images/share_ency_1.jpg"/><meta property="og:image" content="https://medlineplus.gov/images/share_ency_2.jpg"/><meta property="og:image" content="https://medlineplus.gov/images/share_ency_3.jpg"/><meta property="twitter:image" content="https://medlineplus.gov/images/share_ency_1.jpg"/>
<title>Atypical pneumonia: MedlinePlus Medical Encyclopedia</title>
</head>
<body><link href="http://schema.org/Patient" itemprop="audience"/>
<!-- Google Tag Manager -->
<noscript><iframe title="googletagmanager" src="//www.googletagmanager.com/ns.html?id=GTM-MMVM77" height="0" width="0" style="display:none;visibility:hidden">
</iframe>
</noscript>
<!-- End Google Tag Manager -->
<a name="top" id="top">
</a>
<a class="hide-offscreen" href="#start">Skip navigation</a>
<section class="usa-banner" aria-label="Official website of the United States government">
<div class="usa-accordion">
<header class="usa-banner__header">
<div class="usa-banner__inner">
<div class="grid-col-auto">
<img aria-hidden="true" class="usa-banner__header-flag" src="https://medlineplus.gov/uswds/img/us_flag_small.png" alt=""/>
</div>
<div class="grid-col-fill tablet:grid-col-auto" aria-hidden="true">
<p class="usa-banner__header-text">
An official website of the United States government
</p>
<p class="usa-banner__header-action">Heres how you know</p>
</div>
<button type="button" class="usa-accordion__button usa-banner__button" aria-expanded="false" aria-controls="gov-banner-default-default">
<span class="usa-banner__button-text">Heres how you know</span>
</button>
</div>
</header>
<div class="usa-banner__content usa-accordion__content" id="gov-banner-default-default">
<div class="grid-row grid-gap-lg">
<div class="usa-banner__guidance tablet:grid-col-6">
<img class="usa-banner__icon usa-media-block__img" src="https://medlineplus.gov/uswds/img/icon-dot-gov.svg" role="img" alt="" aria-hidden="true"/>
<div class="usa-media-block__body">
<p>
<strong>Official websites use .gov</strong><br/>A
<strong>.gov</strong> website belongs to an official government
organization in the United States.
</p>
</div>
</div>
<div class="usa-banner__guidance tablet:grid-col-6">
<img class="usa-banner__icon usa-media-block__img" src="https://medlineplus.gov/uswds/img/icon-https.svg" role="img" alt="" aria-hidden="true"/>
<div class="usa-media-block__body">
<p>
<strong>Secure .gov websites use HTTPS</strong><br/>A
<strong>lock</strong> (
<span class="icon-lock"><svg xmlns="http://www.w3.org/2000/svg" width="52" height="64" viewBox="0 0 52 64" class="usa-banner__lock-image" role="img" aria-labelledby="banner-lock-description-default" focusable="false">
<title id="banner-lock-title-default">Lock</title>
<desc id="banner-lock-description-default">Locked padlock icon</desc>
<path fill="#000000" fill-rule="evenodd" d="M26 0c10.493 0 19 8.507 19 19v9h3a4 4 0 0 1 4 4v28a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V32a4 4 0 0 1 4-4h3v-9C7 8.507 15.507 0 26 0zm0 8c-5.979 0-10.843 4.77-10.996 10.712L15 19v9h22v-9c0-6.075-4.925-11-11-11z">
</path>
</svg> </span>) or <strong>https://</strong> means youve safely connected to
the .gov website. Share sensitive information only on official,
secure websites.
</p>
</div>
</div>
</div>
</div>
</div>
</section>
<div id="mplus-wrap">
<header>
<div id="mplus-header">
<!-- Orgs
================================================== -->
<div id="mplus-orgs">
<a title="National Institutes of Health" target="_blank" class="nih-org" href="//www.nih.gov/">
<img alt="National Institutes of Health" src="https://medlineplus.gov/images/nihlogo.png" class="nihlogo"/>
</a><a target="_blank" href="https://www.nlm.nih.gov/"> National Library of Medicine </a>
</div>
<!-- Logo
================================================== -->
<div id="mplus-logo" class="years-25">
<a href="https://medlineplus.gov">
<img src="https://medlineplus.gov/images/m_logo_25.png" title="MedlinePlus Trusted Health Information for You" alt="MedlinePlus Trusted Health Information for You"/>
</a>
</div>
<!-- Nav Menu
================================================== -->
<div id="mplus-nav">
<div class="sm-live-area hide-offscreen" aria-live="polite">The navigation menu has been collapsed.</div>
<!-- Menu Button-->
<button type="submit" aria-controls="mplus-menu-list" role="button" title="Menu" class="navmenu-btn" id="sm-menu-btn" aria-pressed="false" tabindex="0">Menu<span class="icon icon-nav-menu">
</span></button><ul class="nav-list" id="mplus-menu-list">
<li><a href="https://medlineplus.gov/healthtopics.html">Health Topics</a></li>
<li><a href="https://medlineplus.gov/druginformation.html">Drugs &amp; Supplements</a></li>
<li><a href="https://medlineplus.gov/genetics/">Genetics</a></li>
<li><a href="https://medlineplus.gov/lab-tests/">Medical Tests</a></li>
<li><a href="https://medlineplus.gov/encyclopedia.html">Medical Encyclopedia</a></li>
<li><a href="https://medlineplus.gov/about/">About MedlinePlus</a></li>
</ul><button type="submit" aria-controls="mplus-search" role="button" title="Search" class="navmenu-btn" id="sm-search-btn" aria-pressed="false" tabindex="0"><span class="hide-offscreen">Show </span>Search<span class="icon icon-nav-search">
</span></button>
<div class="top-1">
<!-- Search
================================================== -->
<form target="_self" title="Search MedlinePlus" action="//vsearch.nlm.nih.gov/vivisimo/cgi-bin/query-meta" method="get" id="mplus-search">
<input type="hidden" value="medlineplus" name="v:project"/>
<input type="hidden" value="medlineplus-bundle" name="v:sources"/>
<div class="form-box text-combo">
<div class="form-area"><label for="searchtext_primary" class="hide-offscreen">Search MedlinePlus</label>
<span role="status" aria-live="polite" class="ui-helper-hidden-accessible">
</span><input type="text" aria-haspopup="true" aria-autocomplete="list" role="textbox" autocomplete="off" name="query" size="40" maxlength="400" title="Site Search input" alt="Site Search input" placeholder="Search MedlinePlus" class="form-text ui-autocomplete-input" id="searchtext_primary"/>
</div>
<div class="button-area">
<button type="submit" alt="Search MedlinePlus" title="Search MedlinePlus" class="form-btn">GO</button>
</div>
</div>
</form>
<!-- Secondary Nav
================================================== -->
<div class="secondarynav">
<ul class="nav-list">
<li><a href="https://medlineplus.gov/about/"><span>About MedlinePlus</span></a></li>
<li><a href="https://medlineplus.gov/whatsnew/"><span>What's New</span></a></li>
<li><a href="https://medlineplus.gov/sitemap.html"><span>Site Map</span></a></li>
<li><a target="_blank" href="https://support.nlm.nih.gov/knowledgebase/category/?id=CAT-01231&amp;category=medlineplus&amp;from=//medlineplus.gov/ency/article/000079.htm"><span>Customer Support</span></a></li>
</ul>
</div>
</div>
<!-- Nav Bar
================================================== -->
<div id="mplus-nav-bar">
<ul class="nav-list">
<li><a href="https://medlineplus.gov/healthtopics.html">Health Topics</a></li><li><a href="https://medlineplus.gov/druginformation.html">Drugs &amp; Supplements</a></li><li><a href="https://medlineplus.gov/genetics/">Genetics</a></li><li><a href="https://medlineplus.gov/lab-tests/">Medical Tests</a></li><li><a href="https://medlineplus.gov/encyclopedia.html">Medical Encyclopedia</a></li>
</ul>
</div>
<a title="Español" id="mplus-lang-toggle" href="../../spanish/ency/article/000079.htm">Español</a>
</div>
</div>
</header>
<!-- Content
================================================== -->
<div id="mplus-content">
<!-- Breadrcumbs -->
<div id="breadcrumbs"><div itemtype="http://schema.org/BreadcrumbList" itemscope="" itemprop="breadcrumb"><span class="hide-offscreen">You Are Here:</span>
<div itemscope itemprop="itemListElement" itemtype="http://schema.org/ListItem">
<a href="https://medlineplus.gov" itemprop="item"><span itemprop="name">Home</span></a>
&rarr;
<meta itemprop="position" content="1"/>
</div>
<div itemscope itemprop="itemListElement" itemtype="http://schema.org/ListItem">
<a href="https://medlineplus.gov/encyclopedia.html" itemprop="item"><span itemprop="name">Medical Encyclopedia</span></a>
&rarr;
<meta itemprop="position" content="2"/>
</div>
</div><div><span>Atypical pneumonia</span></div></div>
<span class="page-url print-only">URL of this page: //medlineplus.gov/ency/article/000079.htm
</span>
<!-- Article -->
<article><div id="d-article"><div class="page-info"><div class="page-title"><a name="start" id="start">
</a><h1 class="with-also" itemprop="name">Atypical pneumonia</h1>
</div><div class="page-actions">
</div>
<noscript>
<span class="js-disabled-message">To use the sharing features on this page, please enable JavaScript.</span>
</noscript></div><div class="main"><div id="ency_summary"><p>Pneumonia is inflamed or swollen lung tissue due to infection with a germ.</p><p>With atypical pneumonia, the infection is caused by different bacteria than the more common ones that cause pneumonia. Atypical pneumonia also tends to have milder symptoms than typical pneumonia.</p></div><section><div class="section"><div class="section-header"><div class="section-title"><h2>Causes</h2></div><div class="section-button"><button type="submit" aria-controls="section-1" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-1"><p>Bacteria that cause atypical pneumonia include:</p><ul><li><a test="test" href="./000082.htm"> Pneumonia</a> caused by the bacteria <em>Mycoplasma pneumoniae</em> often affects people younger than age 40.</li><li>Pneumonia due to <em>Chlamydophila pneumoniae</em> bacteria occurs year round.</li><li>Pneumonia due to <em>Legionella pneumophila</em> bacteria is seen more often in middle-aged and older adults, smokers, and those with chronic illnesses or a weak immune system. It can be more severe. This type of pneumonia is also called <a test="test" href="./000616.htm">Legionnaire disease</a>.</li></ul></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>Symptoms</h2></div><div class="section-button"><button type="submit" aria-controls="section-2" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-2"><p>Pneumonia due to mycoplasma and chlamydophila bacteria is usually mild. Pneumonia due to legionella gets worse during the first 4 to 6 days, and then improves over 4 to 5 days.</p><p>The most common symptoms of pneumonia are:</p><ul><li>Chills</li><li>Cough (with legionella pneumonia, you may cough up bloody mucus)</li><li>Fever, which may be mild or high</li><li>Shortness of breath (may only occur when you exert yourself)</li></ul><p>Other symptoms include:</p><ul><li>Chest pain that gets worse when you breathe deeply or cough</li><li>Confusion, most often in older people or those with legionella pneumonia</li><li>Headache</li><li>Loss of appetite, low energy, and fatigue</li><li>Muscle aches and joint stiffness</li><li>Sweating and clammy skin</li></ul><p>Less common symptoms include:</p><ul><li>Diarrhea (often with legionella pneumonia)</li><li>Ear pain (with mycoplasma pneumonia)</li><li>Eye pain or soreness (with mycoplasma pneumonia)</li><li>Neck lump (with mycoplasma pneumonia)</li><li>Rash (with mycoplasma pneumonia)</li><li>Sore throat (with mycoplasma pneumonia)</li></ul></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>Exams and Tests</h2></div><div class="section-button"><button type="submit" aria-controls="section-3" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-3"><p>People with suspected pneumonia should have a complete medical evaluation. It may be hard for your health care provider to tell whether you have pneumonia, <a test="test" href="./001087.htm">bronchitis</a>, or another respiratory infection, so you may need a <a test="test" href="./003804.htm">chest x-ray</a>. The evaluation is similar for people who have more typical pneumonia.</p><p>Depending on how severe the symptoms are, other tests may be done, including:</p><ul><li><a test="test" href="./003642.htm">Complete blood count</a> (CBC)</li><li>Blood tests to identify the specific bacteria</li><li><a test="test" href="./003857.htm">Bronchoscopy</a> (rarely needed)</li><li><a test="test" href="./003788.htm">CT scan of the chest</a></li><li>Measuring levels of oxygen and carbon dioxide in the blood (<a test="test" href="./003855.htm">arterial blood gases</a>)</li><li>Nose or throat swab to check for bacteria and viruses</li><li>Blood cultures</li><li><a test="test" href="./003861.htm">Open lung biopsy</a> (only done in very serious illnesses when the diagnosis cannot be made from other sources)</li><li><a test="test" href="./003723.htm">Sputum culture</a> to identify the specific bacteria</li><li>Urine test to check for legionella bacteria </li></ul></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>Treatment</h2></div><div class="section-button"><button type="submit" aria-controls="section-4" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-4"><p>To feel better, you can take these self-care measures at home:</p><ul><li>Control your fever with aspirin, non-steroidal anti-inflammatory drugs or NSAIDs (such as ibuprofen or naproxen), or acetaminophen. DO NOT give aspirin to children because it may cause a dangerous illness called <a test="test" href="./001565.htm">Reye syndrome</a>.</li><li>DO NOT take cough medicines without first talking to your provider. Cough medicines may make it harder for your body to cough up the extra sputum.</li><li>Drink plenty of fluids to help loosen secretions and bring up phlegm.</li><li>Get a lot of rest. Have someone else do household chores. </li></ul><p>If needed, you will be prescribed antibiotics.</p><ul><li>You may be able to take antibiotics by mouth at home.</li><li>If your condition is severe, you will likely be admitted to a hospital. There, you will be given antibiotics through a vein (intravenously), as well as oxygen.</li><li>Antibiotics might be used for 2 weeks or more, although fewer days are usually enough.</li><li>Finish all the antibiotics you've been prescribed, even if you feel better. If you stop the medicine too soon, the pneumonia can return and may be harder to treat. </li></ul></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>Outlook (Prognosis)</h2></div><div class="section-button"><button type="submit" aria-controls="section-5" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-5"><p>Most people with pneumonia due to mycoplasma or chlamydophila get better with the right antibiotics. Legionella pneumonia can be severe. It can lead to problems, most often in those with kidney failure, diabetes, chronic obstructive pulmonary disease (COPD), or a weakened immune system. It can also lead to death.</p></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>Possible Complications</h2></div><div class="section-button"><button type="submit" aria-controls="section-6" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-6"><p>Complications that may result include any of the following:</p><ul><li>Brain and nervous system infections, such as <a test="test" href="./000680.htm">meningitis</a>, myelitis, and <a test="test" href="./001415.htm">encephalitis</a></li><li><a test="test" href="./000571.htm">Hemolytic anemia</a>, a condition in which there are not enough red blood cells in the blood because the body is destroying them</li><li>Severe lung damage</li><li>Respiratory failure requiring breathing machine support (ventilator)</li></ul></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>When to Contact a Medical Professional</h2></div><div class="section-button"><button type="submit" aria-controls="section-7" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-7"><p>Contact your provider if you develop fever, cough, or shortness of breath. There are many causes for these symptoms. The provider will need to rule out pneumonia.</p><p>Also, call if you have been diagnosed with this type of pneumonia and your symptoms become worse after improving first.</p></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>Prevention</h2></div><div class="section-button"><button type="submit" aria-controls="section-8" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-8"><p>Wash your hands often and have other people around you do the same.</p><p>Avoid contact with sick people whenever possible.</p><p>If your immune system is weak, stay away from crowds. Ask visitors who have a cold to wear a mask.</p><p>DO NOT smoke. If you do, get help to quit.</p><p>Get appropriate vaccines like flu and COVID-19 shot as prescribed. Ask your provider if you need a <a test="test" href="./007607.htm">pneumonia vaccine</a>.</p></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>Alternative Names</h2></div><div class="section-button"><button type="submit" aria-controls="section-Alt" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-Alt"><p>Walking pneumonia; Community-acquired pneumonia - atypical </p></div></div></section><section><div class="section sec-mb"><div class="section-header"><div class="section-title"><h2>Patient Instructions</h2></div><div class="section-button"><button type="submit" aria-controls="section-carepnt" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div name="Patient Instructions" class="section-body" id="section-carepnt"><ul class="side-nav"><li><a href="../patientinstructions/000017.htm">Pneumonia in adults - discharge</a></li>
<li><a href="../patientinstructions/000011.htm">Pneumonia in children - discharge</a></li>
</ul></div></div></section><section><div class="section sec-mb"><div class="section-header"><div class="section-title"><h2>Images</h2></div><div class="section-button"><button type="submit" aria-controls="section-tnails" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div name="Images" class="section-body" id="section-tnails"><ul class="img-grid group">
<li><img src="//medlineplus.gov/ency/images/ency/tnails/1103t.jpg" alt="Lungs" title="Lungs" class="side-img"/><a href="../imagepages/1103.htm">Lungs</a></li>
<li><img src="//medlineplus.gov/ency/images/ency/tnails/9248t.jpg" alt="Respiratory system" title="Respiratory system" class="side-img"/><a href="../imagepages/9248.htm">Respiratory system</a></li>
</ul></div></div></section><section><div class="section"><div class="section-header"><div class="section-title"><h2>References</h2></div><div class="section-button"><button type="submit" aria-controls="section-Ref" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div class="section-body" id="section-Ref"><p>Baum SG, Goldman DL. Mycoplasma infections. In: Goldman L, Schafer AI, eds. <em>Goldman-Cecil Medicine</em>. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 301.</p><p>Holzman RS, Simberkoff MS, Leaf HL. Mycoplasma pneumoniae and atypical pneumonia. In: Bennett JE, Dolin R, Blaser MJ, eds. <em>Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases</em>. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 183.</p><p>Waxman MA, Moran GJ. Pneumonia. In: Walls RM, ed. <em>Rosen's Emergency Medicine: Concepts and Clinical Practice</em>. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 62.</p></div></div></section>
<section><div class="section"><div class="section-header"><div class="section-title"><h2>Review Date 7/31/2022</h2></div><div class="section-button"><button type="submit" aria-controls="section-version" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div>
<div id="section-version" class="section-body"><p>Updated by: Denis Hadjiliadis, MD, MHS, Paul F. Harron Jr. Professor of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. </p>
</div></div></section><section><div class="section ency-citation"><div class="section-header"><div class="section-title ency-citation"><div id="citation-how-to"><button><span>Learn how to cite this page</span></button></div></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div></div></section><section><div class="section sec-mb"><div class="section-header"><div class="section-title"><h2>Related MedlinePlus Health Topics</h2></div><div class="section-button"><button type="submit" aria-controls="section-mtp" role="button" title="Expand/Collapse section"><span class="icon icon-section-action">
</span></button></div><div class="sm-live-area hide-offscreen" aria-live="polite">
</div></div><div name="Related MedlinePlus Health Topics" class="section-body" id="section-mtp"><ul class="side-nav"><li><a href="https://medlineplus.gov/pneumonia.html">Pneumonia</a></li>
</ul></div></div></section></div></div></article>
</div>
<footer>
<div class="provider-box group">
<div class="urac-logo">
<a href="https://accreditnet.urac.org/directory/#/certification/HCP-2/info"><img src="https://medlineplus.gov/images/CertifiedSeal.png"/></a>
<p class="urac-logo-info">Health Content Provider<br>06/01/2025</p>
</div>
<p class="adam-info">
<a href='javascript:urac_open();'>A.D.A.M., Inc. is accredited by URAC</a>, for Health Content Provider (www.urac.org). URAC's <a href='javascript:hwsopen();'>accreditation program</a> is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s <a href='javascript:edpolopen();'>editorial policy, editorial process</a>, and <a href='javascript:ppopen();'>privacy policy</a>. A.D.A.M. is also a founding member of Hi-Ethics. This site complies with the HONcode standard for trustworthy health information: <a href='javascript:honc_open();'>verify here</a>.
</p>
</div>
<p class="adam-info">
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997-2025 A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
</p>
<div class="adam-logo">
<a href="https://www.adam.com/about" target="_blank"><img width="49" height="10" alt="About A.D.A.M." src="https://medlineplus.gov/ency/images/ency/ftrAdamlogo.gif"/></a>
</div>
<div id="mplus-footer">
<div class="footer1">
<ul class="secondarynav">
<li><a href="https://medlineplus.gov/about/">About MedlinePlus</a></li>
<li><a href="https://medlineplus.gov/whatsnew/">What's New</a></li>
<li><a href="https://medlineplus.gov/sitemap.html">Site Map</a></li>
<li><a name="contact" target="_blank" href="https://support.nlm.nih.gov/knowledgebase/category/?id=CAT-01231&amp;category=medlineplus&amp;from="><span>Customer Support</span></a></li>
</ul>
<ul class="follow-footer">
<li><a href="https://medlineplus.gov/rss.html" class="follow-item">Subscribe to RSS<img src="https://medlineplus.gov/images/feed.png" class="social-media-toolkit-icon" alt="RSS" title="RSS"></a></li>
<li><span class="follow-label">Follow us</span>
<a href="https://twitter.com/medlineplus" class="follow-item" target="_blank"><img src="https://medlineplus.gov/images/i_share_twitter.png" class="follow-icon" alt="X" title="X"></a>
<a href="https://facebook.com/Mplus.gov/" class="follow-item" target="_blank"><img src="https://medlineplus.gov/images/i_share_fb.png" class="follow-icon" alt="Facebook" title="Facebook"></a>
<a href="https://www.instagram.com/mplusgov/" class="follow-item" target="_blank"><img src="https://medlineplus.gov/images/Instagram_Glyph_Gradient_RGB.png" class="follow-icon" alt="Instagram" title="Instagram"></a>
</li>
<li><a href="https://medlineplus.gov/social-media-toolkit/" class="social-media-toolkit-item">Social Media Toolkit<img src="https://medlineplus.gov/images/i_social_media_toolkit.png" class="social-media-toolkit-icon" alt="Social Media Toolkit" title="Social Media Toolkit"></a></li>
</ul>
</div>
<div class="footer2">
<ul>
<li><a href="https://www.nlm.nih.gov/web_policies.html" target="_blank">NLM Web Policies</a></li>
<li><a href="https://medlineplus.gov/about/using/usingcontent/" >Copyright</a></li>
<li><a href="//medlineplus.gov/accessibility.html">Accessibility</a></li>
<li><a href="https://medlineplus.gov/about/using/criteria/">Guidelines for Links</a></li>
<li><a href="//medlineplus.gov/plugins.html">Viewers &amp; Players</a></li>
<li><a href="https://www.hhs.gov/vulnerability-disclosure-policy/index.html" target="_blank">HHS Vulnerability Disclosure</a></li>
<li><a href="https://medlineplus.gov/medlineplus-connect/">MedlinePlus Connect for EHRs</a></li>
<li><a href="https://medlineplus.gov/about/developers/">For Developers</a></li>
</ul>
<div class="address">
<a href="//www.nlm.nih.gov" target="_blank">National Library of Medicine</a>
<span>8600 Rockville Pike, Bethesda, MD 20894</span>
<a href="//www.hhs.gov" target="_blank">U.S. Department of Health and Human Services</a>
<a href="//www.nih.gov" target="_blank">National Institutes of Health</a>
</div>
<div class="return-top"><a href="#top" title="Return to top"><img class="return-top-icon" alt="Return to top" src="https://medlineplus.gov/images/return-top.png"></a></div>
</div>
</div>
</footer>
</div><!-- End Wrap -->
<script src="https://medlineplus.gov/jslib/jquery-3.6.0.min.js" type="text/javascript">
</script>
<script src="https://medlineplus.gov/jslib/mplus-frontend-controls.js" type="text/javascript">
</script>
<!--[if lte IE 9]>
<script src="https://medlineplus.gov/jslib/jquery.placeholder.js" type="text/javascript"></script>
<![endif]-->
<script src="https://medlineplus.gov/jslib/mplus-share.js?id=1112022" type="text/javascript">
</script>
<script src="https://medlineplus.gov/jslib/control.js" type="text/javascript">
</script>
<script src="https://medlineplus.gov/uswds/js/uswds.min.js" type="text/javascript">
</script>
<script src="https://medlineplus.gov/jslib/ency/ency.js" type="text/javascript">
</script>
</body>
</html>