Medical Microbiology

TaxonomyandOverviewofHumanPathogenicBacteria 221

Table3. 9 Continued:OverviewoftheMedicallyMostImportantBacteria

Family

Genus,species

Characteristics Clinical

manifestations

Continued:Section2.

Clostridiumbotulinum Motile,neurotoxinsA,B,

andG

Botulism,usuallyingestion

oftoxinwithfood

Clostridiumperfringens

andfurtherclostridiae

Nonmotile,exotoxins,

andexoenzymes

1 .Anaerobiccellulitis

2.Gasgangrene

(myonecrosis)

Clostridiumdifficile Motile,enterotoxin(toxinA),

cytotoxin(toxinB)

Pseudomembranouscolitis

(oftenantiboticassociated)

Section3.Regular,nonsporing,Gram-positiverods

Listeriamonocytogenes Slenderrods,weakb-hemo-

lysisonbloodagar,motile

at 208 C,ubiquitous(soil)

Meningitis,sepsis

(neonates,immuno-

compromisedpersons),

epidemicgastroenteritis

ErysipelothrixrhusiopathiaeTransmittedfromdiseased

pigs

Erysipeloid(todayrare)

Gardnerellavaginalis Floraofthenormalgenital

mucosa

Contributestovaginosis

Section4.Irregular,nonsporing,Gram-positiverods

Corynebacteriaceae Mostlynormalbacterial

floraoftheskinandmucosa,

aerobic

Onlyfewspeciescause

disease

Corynebacterium

diphtheriae

Clubshape,pleomorphic,

diphtheriaexotoxin(A+B)

Diphtheria(throat,nose,

wounds)

Actinomycetaceae Normalbacterialfloraofthe

mucosa,anaerobicormicro-

aerophilic

Actinomycesisraeliiand

furtherActinomycesspp.

Filaments(alsobranched) Actinomycosis(cervico-

facial,thoracic,abdominal,

pelvic)

Nocardiaceae Nonmotile,obligately

aerobic,filaments,partially

acid-fast

Habitat:soilandaquatic

biotopes

3

Kayser, Medical Microbiology © 2005 Thieme