Medical Microbiology

Mycobacterium 263

TuberculosisBacteria(TB).............................

History.ThetuberculosisbacteriacomplexincludesthespeciesMycobacte-

riumtuberculosis,M.bovis,andtherarespeciesM.africanum.Theclinical

etiologyoftuberculosis,adiseaselongknowntoman,wasworkedoutin

1982 byR.Kochbasedonregularisolationofpathogensfromlesions.Tuber-

culosisisunquestionablyamongthemostintensivelystudiedofallhuman

diseases.Inviewofthefactthattuberculosiscaninfectpracticallyanyorgan

inthebody,itisunderstandablewhyanumberofotherclinicaldisciplines

profitfromthesestudiesinadditiontomicrobiologyandpathology.

Morphologyandculturing.TBareslender,acid-fastrods,0.4lmwide,and

3 – 4 lmlong,nonsporingandnonmotile.Theycanbestainedwithspecial

agents(Ziehl-Neelsen,Kinyoun,fluorescence,p. 21 2f.)(Fig.4. 12 a).

MycobacteriumTuberculosis

Fig.4. 12 aZiehl-Neelsen staining

ofaurine preparation:Fine,red,

acid-fastrods,whichtendtostick

together. Clinical diagnosis: renal

tuberculosis.

b Culture of M. tuberculosis on

eggnutrientsubstrateaccordingto

Lo ̈wenstein-Jensen:afterfourweeks

ofincubationrough,yellowish,cauli-

flowerlikecolonies.

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Kayser, Medical Microbiology © 2005 Thieme