http://debianws.lexgopc.com/wiki143/index.php?action=history&feed=atom&title=Runyon_classificationRunyon classification - Revision history2026-05-09T01:28:26ZRevision history for this page on the wikiMediaWiki 1.43.1http://debianws.lexgopc.com/wiki143/index.php?title=Runyon_classification&diff=3520688&oldid=previmported>Heasnickon: Reorganised sentences2025-05-12T09:59:16Z<p>Reorganised sentences</p>
<p><b>New page</b></p><div>{{Short description|Bacteria classification system}}<br />
{{refimprove|date=November 2009}}<br />
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The Timpe and '''Runyon classification''' of nontuberculous [[mycobacteria]] is based on the rate of growth, production of yellow pigment and whether this pigment was produced in the dark or only after exposure to light.<ref name="pmid2275850">{{cite journal |vauthors=Rogall T, Wolters J, Flohr T, Böttger EC |title=Towards a phylogeny and definition of species at the molecular level within the genus Mycobacterium |journal=International Journal of Systematic Bacteriology |volume=40 |issue=4 |pages=323–30 |date=October 1990 |pmid=2275850 |doi= 10.1099/00207713-40-4-323|doi-access=free }}</ref><br />
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It was introduced by Ernest Runyon in 1959.<ref name="pmid13612432">{{cite journal |author=Runyon EH |title=Anonymous mycobacteria in pulmonary disease |journal=The Medical Clinics of North America |volume=43 |issue=1 |pages=273–90 |date=January 1959 |pmid=13612432 |doi= 10.1016/S0025-7125(16)34193-1}}</ref><br />
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On these bases, the [[nontuberculous mycobacteria]] are divided into four groups. The first three groups are classified as "Slowly growing Mycobacteria" and the fourth group as "Rapid Growers".<br />
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==Slowly growing Mycobacteria==<br />
{{main|Slowly growing Mycobacteria}}<br />
===Runyon I: Photochromogens===<br />
Runyon I organisms ([[photochromogen]]s) are slow growing, and produce a yellow-orange pigment when exposed to light. The group includes<br />
''[[Mycobacterium kansasii]]'', ''[[Mycobacterium intermedium]]'', ''[[Mycobacterium marinum]]'', ''[[Mycobacterium asiaticum]]'', and ''[[Mycobacterium simiae]]''. ''[[Mycobacterium szulgai]]'' is a photochromogen when grown at 24 degrees, and a scotochromogen at 37 degrees. In contrast, Runyon classifications III through IV are considered ''nonphotochromogens'', in that exposure to light does not make them produce pigment which they would not develop in dark growing conditions.<ref>{{cite book |last=Koneman |first=Elmer W. |date=1988 |title=Color atlas and textbook of diagnostic microbiology |url=https://books.google.com/books?id=WiFrAAAAMAAJ&q=%22nonphotochromogenic%22+definition |location=Philadelphia |publisher=Lippincott Williams & Wilkins |page=560 |isbn= 9780397508259 |quote=Runyon has termed these organisms ''nonphotochromogenic'', meaning that exposure to light does not make the[ir] pigment more intense. }}</ref><br />
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===Runyon II: Scotochromogens===<br />
Runyon II organisms ([[scotochromogen]]s) are slow-growing and produce a yellow-orange pigment regardless of whether they are grown in the dark or the light. The group includes ''[[Mycobacterium scrofulaceum]]'' and ''[[Mycobacterium gordonae]]'', among others. ''[[Mycobacterium szulgai]]'' is a scotochromogen when grown at 37 degrees, as mentioned above.<br />
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===Runyon III: Nonchromogens===<br />
Runyon III organisms (nonchromogens) are slow-growing and never produce pigment, regardless of culture conditions. The group includes ''[[Mycobacterium avium]]'' and ''[[Mycobacterium intracellulare]]'' (together known as the MAC complex), ''[[Mycobacterium ulcerans]]'' and numerous other organisms. ''[[Mycobacterium xenopi]]'' is also a nonchromogen. <br />
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==Runyon IV: Rapid Growers==<br />
Runyon IV organisms are rapid growing for mycobacteria (colonies in 5 days). They do not produce pigment.<br />
''[[Mycobacterium fortuitum]]'', ''[[Mycobacterium peregrinum]]'', ''[[Mycobacterium abscessus]]'', ''[[Mycobacterium chelonae]]'', ''[[Mycobacterium thermoresistibile]]'', ''[[Mycobacterium smegmatis]]''.<br />
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Some rapidly growing mycobacteria are considered "late-pigmenting".<ref>{{cite journal | pmid = 12364376 | pmc=126856 | volume=15 | issue=4 | title=Clinical and taxonomic status of pathogenic nonpigmented or late-pigmenting rapidly growing mycobacteria |date=October 2002 | journal=Clin. Microbiol. Rev. | pages=716–46 |vauthors=Brown-Elliott BA, Wallace RJ | doi=10.1128/cmr.15.4.716-746.2002}}</ref><br />
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==References==<br />
{{reflist}}<br />
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{{Mycobacteria}}<br />
{{Gram-positive actinobacteria diseases}}<br />
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[[Category:Mycobacteria|*R]]<br />
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{{Mycobacterium-stub}}</div>imported>Heasnickon