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Do not fill this in! == Diagnosis == {{Main|Tuberculosis diagnosis}} [[File:TB in sputum.png|thumb|''M. tuberculosis'' ([[Ziehl-Neelsen stain|stained red]]) in [[sputum]]]] === Active tuberculosis === Diagnosing active tuberculosis based only on signs and symptoms is difficult,<ref name=DiagP2011>{{cite journal | vauthors = Bento J, Silva AS, Rodrigues F, Duarte R | title = [Diagnostic tools in tuberculosis] | journal = Acta Médica Portuguesa | volume = 24 | issue = 1 | pages = 145–54 | date = 2011 | doi = 10.20344/amp.333 | pmid = 21672452 | s2cid = 76156550 | doi-access = free }}</ref> as is diagnosing the disease in those who have a weakened immune system.<ref name=Clinic2009>{{cite journal | vauthors = Escalante P | s2cid = 639982 | title = In the clinic. Tuberculosis | journal = Annals of Internal Medicine | volume = 150 | issue = 11 | pages = ITC61-614; quiz ITV616 | date = June 2009 | pmid = 19487708 | doi = 10.7326/0003-4819-150-11-200906020-01006 }}</ref> A diagnosis of TB should, however, be considered in those with signs of lung disease or [[constitutional symptoms]] lasting longer than two weeks.<ref name=Clinic2009/> A [[chest X-ray]] and multiple [[sputum culture]]s for [[acid-fast bacilli]] are typically part of the initial evaluation.<ref name=Clinic2009/> [[Interferon gamma release assay|Interferon-γ release assays]] (IGRA) and tuberculin skin tests are of little use in most of the developing world.<ref>{{cite journal | vauthors = Metcalfe JZ, Everett CK, Steingart KR, Cattamanchi A, Huang L, Hopewell PC, Pai M | title = Interferon-γ release assays for active pulmonary tuberculosis diagnosis in adults in low- and middle-income countries: systematic review and meta-analysis | journal = The Journal of Infectious Diseases | volume = 204 | issue = suppl_4 | pages = S1120-9 | date = November 2011 | pmid = 21996694 | pmc = 3192542 | doi = 10.1093/infdis/jir410 }}</ref><ref name="Sester 100–11">{{cite journal | vauthors = Sester M, Sotgiu G, Lange C, Giehl C, Girardi E, Migliori GB, Bossink A, Dheda K, Diel R, Dominguez J, Lipman M, Nemeth J, Ravn P, Winkler S, Huitric E, Sandgren A, Manissero D | display-authors = 6 | title = Interferon-γ release assays for the diagnosis of active tuberculosis: a systematic review and meta-analysis | journal = The European Respiratory Journal | volume = 37 | issue = 1 | pages = 100–11 | date = January 2011 | pmid = 20847080 | doi = 10.1183/09031936.00114810 | doi-access = free }}</ref> IGRA have similar limitations in those with HIV.<ref name="Sester 100–11"/><ref>{{cite journal | vauthors = Chen J, Zhang R, Wang J, Liu L, Zheng Y, Shen Y, Qi T, Lu H | display-authors = 6 | title = Interferon-gamma release assays for the diagnosis of active tuberculosis in HIV-infected patients: a systematic review and meta-analysis | journal = PLOS ONE| volume = 6 | issue = 11 | pages = e26827 | year = 2011 | pmid = 22069472 | pmc = 3206065 | doi = 10.1371/journal.pone.0026827 | veditors = Vermund SH |editor1-link=Sten H. Vermund | bibcode = 2011PLoSO...626827C | doi-access = free }}</ref> A definitive diagnosis of TB is made by identifying ''M. tuberculosis'' in a clinical sample (e.g., sputum, [[pus]], or a [[Tissue (biology)|tissue]] [[biopsy]]). However, the difficult culture process for this slow-growing organism can take two to six weeks for blood or sputum culture.<ref>{{cite book | author = Special Programme for Research & Training in Tropical Diseases |title=Diagnostics for tuberculosis: global demand and market potential|year=2006|publisher=World Health Organization (WHO)|location=Geneva|isbn=978-92-4-156330-7|page=36|url=https://books.google.com/books?id=CFPpcCef4yQC&pg=PA36|url-status=live|archive-url=https://web.archive.org/web/20150906202315/https://books.google.com/books?id=CFPpcCef4yQC&pg=PA36|archive-date=6 September 2015}}</ref> Thus, treatment is often begun before cultures are confirmed.<ref name=NICE2011/> [[Nucleic acid amplification test]]s and [[adenosine deaminase]] testing may allow rapid diagnosis of TB.<ref name=DiagP2011/> Blood tests to detect antibodies are not [[sensitivity and specificity|specific or sensitive]], so they are not recommended.<ref>{{cite journal | vauthors = Steingart KR, Flores LL, Dendukuri N, Schiller I, Laal S, Ramsay A, Hopewell PC, Pai M | display-authors = 6 | title = Commercial serological tests for the diagnosis of active pulmonary and extrapulmonary tuberculosis: an updated systematic review and meta-analysis | journal = PLOS Medicine | volume = 8 | issue = 8 | page= e1001062 | date = August 2011 | pmid = 21857806 | pmc = 3153457 | doi = 10.1371/journal.pmed.1001062 | doi-access = free | veditors = Evans C }}</ref> === Latent tuberculosis === {{Main|Latent tuberculosis}} [[File:Mantoux tuberculin skin test.jpg|thumb|left|Mantoux tuberculin skin test]] The [[Mantoux test|Mantoux tuberculin skin test]] is often used to screen people at high risk for TB.<ref name=Clinic2009/> Those who have been previously immunized with the Bacille Calmette-Guerin vaccine may have a false-positive test result.<ref name=Rothel_2005>{{cite journal | vauthors = Rothel JS, Andersen P | s2cid = 25423684 | title = Diagnosis of latent Mycobacterium tuberculosis infection: is the demise of the Mantoux test imminent? | journal = Expert Review of Anti-Infective Therapy | volume = 3 | issue = 6 | pages = 981–93 | date = December 2005 | pmid = 16307510 | doi = 10.1586/14787210.3.6.981 }}</ref> The test may be falsely negative in those with [[sarcoidosis]], [[Hodgkin's lymphoma]], [[malnutrition]], and most notably, active tuberculosis.<ref name=Robbins/> [[Interferon gamma release assay]]s, on a blood sample, are recommended in those who are positive to the Mantoux test.<ref name=NICE2011>{{NICE|117|Tuberculosis|2011}}</ref> These are not affected by immunization or most [[environmental mycobacteria]], so they generate fewer [[false-positive]] results.<ref>{{cite journal | vauthors = Pai M, Zwerling A, Menzies D | title = Systematic review: T-cell-based assays for the diagnosis of latent tuberculosis infection: an update | journal = Annals of Internal Medicine | volume = 149 | issue = 3 | pages = 177–84 | date = August 2008 | pmid = 18593687 | pmc = 2951987 | doi = 10.7326/0003-4819-149-3-200808050-00241 }}</ref> However, they are affected by ''M. szulgai'', ''M. marinum'', and ''M. kansasii''.<ref>{{cite book| veditors = Jindal SK |title=Textbook of Pulmonary and Critical Care Medicine|publisher=Jaypee Brothers Medical Publishers|location=New Delhi|isbn=978-93-5025-073-0|page=544|url=https://books.google.com/books?id=rAT1bdnDakAC&pg=PA544|year=2011|url-status=live|archive-url=https://web.archive.org/web/20150906185238/https://books.google.com/books?id=rAT1bdnDakAC&pg=PA544|archive-date=6 September 2015}}</ref> IGRAs may increase sensitivity when used in addition to the skin test, but may be less sensitive than the skin test when used alone.<ref>{{cite journal | vauthors = Amicosante M, Ciccozzi M, Markova R | title = Rational use of immunodiagnostic tools for tuberculosis infection: guidelines and cost effectiveness studies | journal = The New Microbiologica | volume = 33 | issue = 2 | pages = 93–107 | date = April 2010 | pmid = 20518271 }}</ref> The [[US Preventive Services Task Force]] (USPSTF) has recommended screening people who are at high risk for latent tuberculosis with either tuberculin skin tests or [[interferon-gamma release assay]]s.<ref>{{cite journal | vauthors = Bibbins-Domingo K, Grossman DC, Curry SJ, Bauman L, Davidson KW, Epling JW, García FA, Herzstein J, Kemper AR, Krist AH, Kurth AE, Landefeld CS, Mangione CM, Phillips WR, Phipps MG, Pignone MP | display-authors = 6 | title = Screening for Latent Tuberculosis Infection in Adults: US Preventive Services Task Force Recommendation Statement | journal = JAMA | volume = 316 | issue = 9 | pages = 962–9 | date = September 2016 | pmid = 27599331 | doi = 10.1001/jama.2016.11046 | doi-access = free }}</ref> While some have recommend testing health care workers, evidence of benefit for this is poor {{as of|2019|lc=yes}}.<ref>{{cite journal | vauthors = Gill J, Prasad V | title = Testing Healthcare Workers for Latent Tuberculosis: Is It Evidence Based, Bio-Plausible, Both, Or Neither? | journal = The American Journal of Medicine | volume = 132 | issue = 11 | pages = 1260–1261 | date = November 2019 | pmid = 30946831 | doi = 10.1016/j.amjmed.2019.03.017 | doi-access = free }}</ref> The [[Centers for Disease Control and Prevention]] (CDC) stopped recommending yearly testing of health care workers without known exposure in 2019.<ref>{{cite journal | vauthors = Sosa LE, Njie GJ, Lobato MN, Bamrah Morris S, Buchta W, Casey ML, Goswami ND, Gruden M, Hurst BJ, Khan AR, Kuhar DT, Lewinsohn DM, Mathew TA, Mazurek GH, Reves R, Paulos L, Thanassi W, Will L, Belknap R | display-authors = 6 | title = Tuberculosis Screening, Testing, and Treatment of U.S. Health Care Personnel: Recommendations from the National Tuberculosis Controllers Association and CDC, 2019 | journal = MMWR. Morbidity and Mortality Weekly Report | volume = 68 | issue = 19 | pages = 439–443 | date = May 2019 | pmid = 31099768 | pmc = 6522077 | doi = 10.15585/mmwr.mm6819a3 }}</ref> Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here. You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Christianpedia:Copyrights for details). Do not submit copyrighted work without permission! Cancel Editing help (opens in new window) Discuss this page