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Do not fill this in! === Mycobacteria === {{Main| Mycobacterium tuberculosis}} [[File:Mycobacterium tuberculosis.jpg|thumb|[[Scanning electron micrograph]] of ''M. tuberculosis'']] The main cause of TB is ''[[Mycobacterium tuberculosis]]'' (MTB), a small, [[aerobic organism|aerobic]], nonmotile [[bacillus]].<ref name=ID10/> The high [[lipid]] content of this [[pathogen]] accounts for many of its unique clinical characteristics.<ref>{{cite book | vauthors = Southwick F |title=Infectious Diseases: A Clinical Short Course, 2nd ed. |publisher=McGraw-Hill Medical Publishing Division |year=2007 |pages=104, 313–14 |chapter=Chapter 4: Pulmonary Infections |isbn=978-0-07-147722-2}}</ref> It [[cell division|divides]] every 16 to 20 hours, which is an extremely slow rate compared with other bacteria, which usually divide in less than an hour.<ref>{{cite book| vauthors = 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=525|url=https://books.google.com/books?id=rAT1bdnDakAC&pg=PA525|year=2011|url-status=live|archive-url=https://web.archive.org/web/20150906211342/https://books.google.com/books?id=rAT1bdnDakAC&pg=PA525|archive-date=6 September 2015}}</ref> Mycobacteria have an [[Bacterial cell structure|outer membrane]] lipid bilayer.<ref name=Niederweis2010>{{cite journal | vauthors = Niederweis M, Danilchanka O, Huff J, Hoffmann C, Engelhardt H | title = Mycobacterial outer membranes: in search of proteins | journal = Trends in Microbiology | volume = 18 | issue = 3 | pages = 109–16 | date = March 2010 | pmid = 20060722 | pmc = 2931330 | doi = 10.1016/j.tim.2009.12.005 }}</ref> If a [[Gram stain]] is performed, MTB either stains very weakly "Gram-positive" or does not retain dye as a result of the high lipid and [[mycolic acid]] content of its cell wall.<ref name=Madison_2001>{{cite journal | vauthors = Madison BM | title = Application of stains in clinical microbiology | journal = Biotechnic & Histochemistry | volume = 76 | issue = 3 | pages = 119–25 | date = May 2001 | pmid = 11475314 | doi = 10.1080/714028138 }}</ref> MTB can withstand weak [[disinfectant]]s and survive in a [[Endospore|dry state]] for weeks. In nature, the bacterium can grow only within the cells of a [[host (biology)|host]] organism, but ''M. tuberculosis'' can be cultured [[in vitro|in the laboratory]].<ref name=Parish_1999>{{cite journal | vauthors = Parish T, Stoker NG | s2cid = 28960959 | title = Mycobacteria: bugs and bugbears (two steps forward and one step back) | journal = Molecular Biotechnology | volume = 13 | issue = 3 | pages = 191–200 | date = December 1999 | pmid = 10934532 | doi = 10.1385/MB:13:3:191 | doi-access = free }}</ref> Using [[histology|histological]] stains on [[expectorate]]d samples from [[phlegm]] (also called sputum), scientists can identify MTB under a microscope. Since MTB retains certain stains even after being treated with acidic solution, it is classified as an [[acid-fast bacillus]].<ref name=Robbins/><ref name="Madison_2001"/> The most common acid-fast staining techniques are the [[Ziehl–Neelsen stain]]<ref name=Stain2000>{{cite book |title=Medical Laboratory Science: Theory and Practice |publisher=Tata McGraw-Hill |location=New Delhi |year=2000 |page=473 |isbn=978-0-07-463223-9 |url=https://books.google.com/books?id=lciNs3VQPLoC&pg=PA473 |url-status=live |archive-url=https://web.archive.org/web/20150906213737/https://books.google.com/books?id=lciNs3VQPLoC&pg=PA473 |archive-date=6 September 2015 }}</ref> and the [[Kinyoun stain]], which dye acid-fast bacilli a bright red that stands out against a blue background.<ref>{{cite web |title=Acid-Fast Stain Protocols |url=http://www.microbelibrary.org/component/resource/laboratory-test/2870-acid-fast-stain-protocols |access-date=26 March 2016 |date=21 August 2013 |url-status=dead |archive-url=https://web.archive.org/web/20111001132818/http://www.microbelibrary.org/component/resource/laboratory-test/2870-acid-fast-stain-protocols |archive-date=1 October 2011 }}</ref> [[Auramine-rhodamine stain]]ing<ref name=Kommareddi_1984>{{cite journal | vauthors = Kommareddi S, Abramowsky CR, Swinehart GL, Hrabak L | title = Nontuberculous mycobacterial infections: comparison of the fluorescent auramine-O and Ziehl-Neelsen techniques in tissue diagnosis | journal = Human Pathology | volume = 15 | issue = 11 | pages = 1085–9 | date = November 1984 | pmid = 6208117 | doi = 10.1016/S0046-8177(84)80253-1 }}</ref> and [[Fluorescence microscope|fluorescence microscopy]]<ref>{{cite book | vauthors = van Lettow M, Whalen C |title=Nutrition and health in developing countries|year=2008|publisher=Humana Press|location=Totowa, N.J. | veditors = Semba RD, Bloem MW |isbn=978-1-934115-24-4 |page=291 |url=https://books.google.com/books?id=RhH6uSQy7a4C&pg=PA291 |edition=2nd|url-status=live|archive-url=https://web.archive.org/web/20150906215906/https://books.google.com/books?id=RhH6uSQy7a4C&pg=PA291|archive-date=6 September 2015}}</ref> are also used. The [[Mycobacterium tuberculosis complex|''M. tuberculosis'' complex]] (MTBC) includes four other TB-causing [[mycobacterium|mycobacteria]]: ''[[Mycobacterium bovis|M. bovis]]'', ''[[Mycobacterium africanum|M. africanum]]'', ''[[Mycobacterium canettii|M. canettii]]'', and ''[[Mycobacterium microti|M. microti]]''.<ref>{{cite journal | vauthors = van Soolingen D, Hoogenboezem T, de Haas PE, Hermans PW, Koedam MA, Teppema KS, Brennan PJ, Besra GS, Portaels F, Top J, Schouls LM, van Embden JD | display-authors = 6 | title = A novel pathogenic taxon of the Mycobacterium tuberculosis complex, Canetti: characterization of an exceptional isolate from Africa | journal = International Journal of Systematic Bacteriology | volume = 47 | issue = 4 | pages = 1236–45 | date = October 1997 | pmid = 9336935 | doi = 10.1099/00207713-47-4-1236 | doi-access = free }}</ref> ''M. africanum'' is not widespread, but it is a significant cause of tuberculosis in parts of Africa.<ref>{{cite journal | vauthors = Niemann S, Rüsch-Gerdes S, Joloba ML, Whalen CC, Guwatudde D, Ellner JJ, Eisenach K, Fumokong N, Johnson JL, Aisu T, Mugerwa RD, Okwera A, Schwander SK | display-authors = 6 | title = Mycobacterium africanum subtype II is associated with two distinct genotypes and is a major cause of human tuberculosis in Kampala, Uganda | journal = Journal of Clinical Microbiology | volume = 40 | issue = 9 | pages = 3398–405 | date = September 2002 | pmid = 12202584 | pmc = 130701 | doi = 10.1128/JCM.40.9.3398-3405.2002 }}</ref><ref>{{cite journal | vauthors = Niobe-Eyangoh SN, Kuaban C, Sorlin P, Cunin P, Thonnon J, Sola C, Rastogi N, Vincent V, Gutierrez MC | display-authors = 6 | title = Genetic biodiversity of Mycobacterium tuberculosis complex strains from patients with pulmonary tuberculosis in Cameroon | journal = Journal of Clinical Microbiology | volume = 41 | issue = 6 | pages = 2547–53 | date = June 2003 | pmid = 12791879 | pmc = 156567 | doi = 10.1128/JCM.41.6.2547-2553.2003 }}</ref> ''M. bovis'' was once a common cause of tuberculosis, but the introduction of [[pasteurisation|pasteurized milk]] has almost eliminated this as a public health problem in developed countries.<ref name=Robbins/><ref>{{cite journal | vauthors = Thoen C, Lobue P, de Kantor I | title = The importance of Mycobacterium bovis as a zoonosis | journal = Veterinary Microbiology | volume = 112 | issue = 2–4 | pages = 339–45 | date = February 2006 | pmid = 16387455 | doi = 10.1016/j.vetmic.2005.11.047 }}</ref> ''M. canettii'' is rare and seems to be limited to the [[Horn of Africa]], although a few cases have been seen in African emigrants.<ref>{{cite book| vauthors = Acton QA |title=Mycobacterium Infections: New Insights for the Healthcare Professional|year=2011|publisher=ScholarlyEditions|isbn=978-1-4649-0122-5|page=1968|url=https://books.google.com/books?id=g2iFfV6uEuAC&pg=PA1968|url-status=live|archive-url=https://web.archive.org/web/20150906201531/https://books.google.com/books?id=g2iFfV6uEuAC&pg=PA1968|archive-date=6 September 2015}}</ref><ref>{{cite journal | vauthors = Pfyffer GE, Auckenthaler R, van Embden JD, van Soolingen D | title = Mycobacterium canettii, the smooth variant of M. tuberculosis, isolated from a Swiss patient exposed in Africa | journal = Emerging Infectious Diseases | volume = 4 | issue = 4 | pages = 631–4 | date = 1998 | pmid = 9866740 | pmc = 2640258 | doi = 10.3201/eid0404.980414 }}</ref> ''M. microti'' is also rare and is seen almost only in immunodeficient people, although its [[prevalence]] may be significantly underestimated.<ref>{{cite journal | vauthors = Panteix G, Gutierrez MC, Boschiroli ML, Rouviere M, Plaidy A, Pressac D, Porcheret H, Chyderiotis G, Ponsada M, Van Oortegem K, Salloum S, Cabuzel S, Bañuls AL, Van de Perre P, Godreuil S | display-authors = 6 | title = Pulmonary tuberculosis due to Mycobacterium microti: a study of six recent cases in France | journal = Journal of Medical Microbiology | volume = 59 | issue = Pt 8 | pages = 984–989 | date = August 2010 | pmid = 20488936 | doi = 10.1099/jmm.0.019372-0 | doi-access = free }}</ref> Other known pathogenic mycobacteria include ''[[Mycobacterium leprae|M. leprae]]'', ''[[Mycobacterium avium complex|M. avium]]'', and ''[[Mycobacterium kansasii|M. kansasii]]''. The latter two species are classified as "[[nontuberculous mycobacteria]]" (NTM) or atypical mycobacteria. NTM cause neither TB nor [[leprosy]], but they do cause lung diseases that resemble TB.<ref name=ALA_1997>{{cite journal | author = American Thoracic Society | title = Diagnosis and treatment of disease caused by nontuberculous mycobacteria | journal = American Journal of Respiratory and Critical Care Medicine | volume = 156 | issue = 2 Pt 2 | pages = S1–25 | date = August 1997 | pmid = 9279284 | doi = 10.1164/ajrccm.156.2.atsstatement }}</ref>[[File:TB poster.jpg|thumb|Public health campaigns in the 1920s tried to halt the spread of TB.]] 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. 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