Non motile baccilus acid fast auramine

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Non-motileBaccilusAcid Fast +Auramine-rhodaminestainsorange-yellowProduces niacinReduces nitrateMycolicaciddetectable by HPLCSlow growing (3-8weeks) on agarDroplet inhalationand depositionAfter exposure, 30%become infectedOf non-immunocompromisedhosts, 5% developactive TB within 2years after exposure,5-10%thereafterHIV andimmunosuppressedhosts: 30% risk ofdeveloping active TB1 year after exposurePulmonary macrophageingestion, spread tohematogenouslymphnodes, followed bylymphohematogenousdisseminationCell-mediated responserequires6-12 weeks ifnever exposed beforeMajor response isgranulomaformation:macrophages arerecruited to help containthe infectionIf other cells arerecruited, cytokinerelease may result inpneumonoticis, caseationnecrosis, tissuedestruction and fibrosisNon-HIVFeverNighsweatsFatigueWeight lossProductive coughChest painCavitaryupper lobe orprogressive lower lobepneumonia20% have extrapulmonarysymptoms (CNS,lymphoreticular, abdominal,renal, bone)HIVMore acute or severepresentationsMiliaryTBExtrapulmonarysymptoms in40-50%Sputumacid fast bacteriasmear and culture (grows on LJor 7H10 agar over 3-8 weeks)Tissue, body fluid cultureBACTEC MGIT liquid culture:uses modified 7H10 broth withoxygen concentration-sensitivefluorescent sensorTuberculin skin testT-cell based assays (e.g.quantiFERON-TB Gold in-Tubedetects IFN-γrelease inresponse to MTB-specificproteins)Nucleic acid amplification(NAAT)Line probe assay: DNA or RNAreverse hybridized ontonitrocellulose strips to detectdifferent MTB speciesTreatmentAll initial culturesshould have drugsensitivitytest (culture,line probe assay forspecific resistancemutations, CepheidGeneXpertMTB/RIFNAAT)PreventionDiagnose early andinitiate propertreatmentIsolate suspect casesSurveillance ofhouseholdcontacts andhealthcare workers.MycobacteriumaviumcomplexMycobacteriumintracellulare(moreNonchromogenicSlow growingInhaled or ingestedGrow in macrophagesand survive by inhibitingphagosome-lysosomefusionColonize the respiratoryNon-immunocompromisedchildrenCervicallymphadenitisNon-immunocompromisedChestCTBlood, tissue cultureNAATClarithomycinorAzithromycin +ethambutol+fluoroquinolonesIsoniazidDOES NOTintracellulare(morecommon in SE U.S.,also among peoplewith existing lungdamage)MycobacteriumAvium(moreubiquitous, causesdisseminated diseasein AIDS and hairy cellleukemia patients)Colonize the respiratoryand/or GI tractIncreased susceptibilitywith genetic defects in IL-12, IL-12 receptor, IFN-γ,IFN-γreceptor, hairy cellleukemia, HIV/AIDSNon-immunocompromisedadultsindolent, chronicallyprogressive granulomatousorinterstitial lung diseasewithcough, sputum, weight loss,fever, cavitation, nodulesHIVDisseminated multiorgandisease, spreads tolymphoreticularorgansIsoniazidDOES NOTworkProphylaxis for AIDS

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Term
Spring
Professor
staff
Tags
Bacteria, Escherichia coli, gram negative bacteria, GI Tract, Gram positive bacteria

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