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Enterobacteriaceae
Dr. Berek ZsuzsaDr. Berek Zsuzsa08 November 201108 November 2011
Normal bacterium Flora of the Gastrointestinal tract
GRAM NEGATIVE RODS
AEROBBordetellaBrucellaFrancisella
PseudomonasAcinetobacterLegionella
FACULTATIVE ANAEROBHaemophilusPasteurella
Familia:EnterobacteriaceaeVibrionaceae
CardiobacteriumEikenellaKingellaActinobacillus
ANAEROBBacteroidesPrevotellaPorphyromonasFusobacterium
MICROAEROPHILCampylobacterHelicobacter
Normal bacteriumFlora of the
Gastrointestinal tract
Normal bacterium flora of theGastrointestinal tract
• Significance:experiments with germ-free animals
•• StomachStomach (103–106 cfu/g)– Low pH– Resident micro flora Ø– Transient flora +– Hypochlorhydria, stasis ⇒
Lactobacillus (Boas-Oppler) & Sarcinaspp.
•• Small intestineSmall intestine (105–107 cfu/g)– Digestive enzymes & bile, rapid peristaltic– Resident micro flora Ø– Transient flora +
•• Large intestineLarge intestine (109–1011 cfu/g)– Abundant resident micro flora
Anaerobes90–95% of the species∼ 1011 cfu/g faecesResident
Bifidobacterium bifidumBacteroides fragilisEubacterium spp.Clostridium spp.
TransientAnaerobe KokkenFusobakterienLactobacillen
Facultative anaerobes5–10% of the species∼ 103–109 cfu/g faecesResident
Escherichia coliEnterococcus spp.
TransientKlebsiella spp.Enterobacter spp.Proteus spp.Providencia spp.Pseudomonas spp.Bacillus spp.yeasts, Protozoa
Normal bacterium Flora of the colon inadults (>400 Species)
• Breast feeding– Resident
• Bifidobacteria (pH 5,5)– Colonisation of other species is
inhibited (vitamin K substitution!)
• Composite feeding– Primarily
• Facultative anaerobes– Later
• Bacteroides fragilis
Normal bacterium flora of thecolon in children
Scanning electron micrograph of the colon mucosa of rat
⎢: bacterium layer, L: lumen, B: bacteria, T: intestinal tissue
Magnification: 262× Magnification: 2.624×
Significance of the normal bacterial flora of the colon
• Decomposition of some nutrients, enterohepaticrecirculation of bile
• Production of vitamins: vitamin K & B-complex• Production of gases ⇒ distension ⇒ normal
peristaltic• Constant physical & chemical stimuli ⇒ constant
mucosal turnover• Biofilm formation, blocking epithelial receptors,
competition for nutrients, bacteriostatic products ⇒inhibition of the colonisation of pathogenic bacteria
• Constant antigen stimulus ⇒ extrauterindevelopment and functioning of the immune system
Role of normal bacterial flora of the colon in pathological processes
•• Extra intestinal infectionsExtra intestinal infections
•• TranslocationTranslocationImmune Immune
compromised patientscompromised patientsObstructionsObstructionsShockShock
ConsequencesConsequencesEndotoxaemiaBacteriaemiaSepsis
Bacterial translocation in rat after experimental intestinal obstruction
AA BB
A: A: lifting of the epithelial cells from the lifting of the epithelial cells from the
lamina lamina propriapropria & bacterial invasion& bacterial invasion
B: B: coccicocci and rods inand rods in
the the submucosalsubmucosal lymphatic vesselslymphatic vessels
Alteration of the balance of the normal bacterial flora of the colon
•• CausesCauses– Malnutrition– Broad spectrum per os antibacterial therapy
•• ConsequencesConsequences– Maldigestion & maladsorption, vitamin deficiency– Alteration of the normal peristaltic, increased
gastrointestinal gas formation•• Antibiotic associated diarrhoeaAntibiotic associated diarrhoea
– Mild: „common” diarrhoea– Severe: pseudomembranous colitis
(Clostridium difficile)
PseudomembranousPseudomembranous colitiscolitis
Thickened wall of the colon Thickened wall of the colon transversumtransversum
Characteristic yellow plaquesCharacteristic yellow plaquesC. difficileC. difficile & & neutrophilsneutrophils
Gram negative facultativeanaerobic rods
Enterobacteriaceae I.
Enterobacteriaceae
Morphology: - Gram negative rods- pili (ex.: Klebsiella, Shigella)
Cultivation:easy, simple (Agar, Blood-agar) MediaDifferentiation: pathogenic-facultative pathogenic(Biochemical reactions)
a) Selective-Mediab) Differential-Mediac) Indicator-Media
Antigens and Virulence factors:O (cell-wall)H (Flagella)K (capsule)surface ProteinsPiliExotoxinsEndotoxin
Enterobacteriaceae
Enterobacteriaceae
Facultative pathogensgenusEscherichia
Klebsiella GroupEnterobacterEdwardsiellaCitrobacter
Proteus GroupSerratiaProvidenciaMorganella
Obligate pathogens (genera)E. Coli
ETEC (enterotoxic)EPEC (enteropathogen)EIEC (enteroinvasive)EHEC (enterohemorrhagic)EAggEC (enteroaggregativ)
ShigellaS. dysenteriaeS. flexneriS. boydiiS. sonnei
SalmonellaS. typhiS. paratyphi
YersiniaY. pestisY. pseudotuberculosisY. enterocolitica
Enterobacteriaceae - Facultative PathogensKlebsiella, Proteus, Escherichia etc. Extraintestinal clinical findings – ALL purulent infections:
a) urinary tract infectionsb) cholecystitis, cholangitisc) peritonitis (local, diffuse)d) pneumoniae) meningitisf) wound infectionsg) sepsish) iatrogen/nosokomial infections
Diagnosis: isolation, identificationTreatment: antibiogram (ESBL)
Serratia marcescens - Serratia marcescens Durch Prodigiosin rotgefärbte Kolonien von Serratia marcescens auf Agargel.
www.biologie.de
pathmicro.med.sc.edu
TSI Medium Identification
Top row, Proteus vulgaris; second row, unidentified enteric bacterium; thirdrow, Klebsiella pneumoniae; bottom row, Vibrio alginolyticus.
helio
s.bt
o.ed
.ac.
ukId
entif
icat
ion
E. coli with Fimbriae
Urinary tract infections (UTI)Urinary tract infections (UTI)
www.spiceisle.com
•• E. coli E. coli (80%)(80%)– Predisposition– Ascending
(rarely haematogenic)– Cystitis, pyelonephritis– Virulence factors (UPEC-strains)
• Haemaggl. adhesion fimbriae– Mannose resistant (MR) fimbriae
(F-antigen), P-fimbriae (blood group P substance) ⇒pyelonephritis
– Mannose sensitive (MS) fimbriae ⇒cystitis
• Haemolysines
• P. mirabilis, P. vulgaris– Predisposition– Ascending infection– Nosocomial
(catheter, operation)– Virulence factors
• Flagellae: motility
• Adhesion fimbriae• Urease
(pH↑, irritation, urinary stones)
P. mirabilis: Swarming
www.sciencebuddies.org
Urinary tract infections (UTI)Urinary tract infections (UTI)
P. mirabilis
ww
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nrc.
gc.c
a
swarming
P. mirabilis
Swarming- On cells
www.nrc-cnrc.gc.ca
P. mirabilis
Swarming- On cells
www.nrc-cnrc.gc.ca
biology.clc.uc.edu
Proteus vulgaris flagellar - staining
A: Proteus, Providentia – B: Urease Test - / +
helios.bto.ed.ac.uk
Neonatal Meningitis & Sepsis
•• E. coliE. coli K1K1(80–85%)
• K1-antigen – Identical with
Meningococcus B-ag– Tolerance ⇒
no antibody response– Translocation
Pneumonia
• Nosokomial• Predisposition• Pathogens
E. coli,K. pneumoniae,K. oxytoca, Enterobacter spp. Bronchopneumonia Lobar pneumonia
(Friedländer)K. pneumoniae
Klebsiella pneumoniae – Friedländer Pneumonia
ww
w.b
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n.ed
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www.icbm.de
Klebsiella pneumoniae
mucoid colonies – capsule
www.lf3.cuni.cz
Klebsiella pneumoniae
Klebsiella pneumoniae
Enterobacter cloacae Klebsiella pneumoniaeMucoid colonies
Intra-abdominal Infections
Diffuse peritonitis after perforation of the colon
Free abdominal air below the diaphragm: perforation
Enterobacteriaceae
Facultative pathogensgenusEscherichia
Klebsiella GroupEnterobacterEdwardsiellaCitrobacter
Proteus GroupSerratiaProvidentiaMorganella
Obligate pathogens (genera)Escherichia coli (species)
ETEC (enterotoxic)EPEC (enteropathogen)EIEC (enteroinvasive)EHEC (enterohemorrhagic)EAggEC (enteroaggregativ)
ShigellaS. dysenteriaeS. flexneriS. boydiiS. sonnei
SalmonellaS. typhiS. paratyphi
YersiniaY. pestisY. pseudotuberculosisY. enterocolitica
FIGURE 25-1 Virulence mechanisms of E coli.
Medmicro
EIEC
ETEC
EAggEC
FIGURE 25-2 Pathogenesis of E. coli diarrhoeal disease.
Medmicro
Pathogenic E. coli strains-1
ETEC (enterotoxic)LT (heat-labile) ST (heat-stable)
ST mode of action (hyperactivation): ADP-Rybosilation GuanilcyclasecGMP water and electrolyte loss
Fimbriae (CFA = colonisation factor antigens)
FIGURE 25-3 Cellular pathogenesis of E coli having CFA pili.
Medmicro
ETEC
Fig.4.26 Enterotoxigenic E. coli infection. Transmission electron micrograph showing bacteria adhering to the brush-border of human intestinal mucosal cells. By courtesy of Dr. S. Knutton
ETEC
FIGURE 25-4 Laboratory methods for isolation and identification of ETEC.
Medmicro
Fig. 4.14 Bacterial diarrhea. Y1 adrenal cell assay for E. coli LT enterotoxin, showing normal cells (left) and cells after exposure to LT toxin (right). Note disruption of monolayer and rounding up cells. By courtesy of Dr. H.L. DuPont.
ETEC
Pathogenic E. coli strains-2-3EPEC (enteropathogenic) O26; O55; O111; O126…
Adhaesion: Adherence Factor (EAF)Bundle Forming Pilus (BFP)Type III. Secretion-system*: Protein filaments (EspA)Tir (translocated intimin receptor)Intimin (eae*) Actin; brush-border lost cell death* Chromosome coded
EAggEC (enteroaggregativ)Fimbriae, ST-like, Haemolysin-like Toxin
Fig.4.19 E. coli diarrhea. Electron micrograph of enteropathogenicE. coli (arrowed) attached to mucosal epithelial cells of ileum. The microvillus border of the epithelial cells has been largely destroyed by bacteria and the cells show signs of degeneration. X3000 By courtesy of Dr. J.R. Cantey
EPEC
Fig.4.27 Enteropathogenic E. coli infection. Electron micrograph showing close, localized adherence of bacteria to human intestinal mucosal cells and localized destruction of microvilli. By courtesy of Dr. S. Knutton
EPEC
Fig. 4.28 Enteropathogenic E. coli infection. Fluorescent actin test specific for EPEC organisms. Left: fluorescent microscopy showing aggregated actin. Right: phase contrast microscopy showing location of bacteria. By courtesy of dr. S. Knutton
EPEC
Pathogenic E. coli strains-4
EIEC (enteroinvasive)
O28; O32; O112; O115; O124, O136; O143, O144 u.a.
Pathogenesis:s. Shigella ProteinsType III. Secretion-system
FIGURE 25-5 Cellular pathogenesis of invasive E coli
EIEC
Fig. 4.17 Enteroinvasive E. coli infection. Invasion of mucosal layer of the intestine by E. coli organisms. There is necrosis of the mucosal layer at the site of invasion (left). Transmission electron micrograph showing enteroinvasive E. coli organisms within HEp-2 cell (right). By courtesy of Dr. S. Knutton.
EIEC
Fig. 4.31 Enteroinvasive E. coli infection. EIEC organisms invading HeLa cells in vitro. By courtesy of Dr. S. Knutton.
EIEC
Pathogenic E. coli strains-5
EHEC (enterohemorrhagic) = VTEC O157:H7
SLT = Verotoxin = Shiga Toxin (stx1, 2, 2c) Mode of action: Protein synthesis inhibitor cytotoxic Haemolysin
Clinical finding, disease:HUS (haemolytic uraemic syndrome)
Haemolytic AnaemiaTrombocytopeniaacute kidney failure
Haemorrhagic colitis
Pathogene E. coli strains
Transmission electronmicrograph of Escherichia coli O157:H7
pathmicro.med.sc.edu
EHEC(enterohaemorrhagic)= VTEC O157:H7
EHEC (enterohemorrhagisch) = VTEC O157:H7
Fig. 4.29 Enterohaemorrhagic E. coli infection. Assay for Shiga-like toxin (Verotoxin) produced by EHEC (Serotype O157). Left: Normal monolayer of Vero cells. Right: Destruction of Vero cells by the toxin. By courtesy of Dr. S. Knutton
Fig. 4.30 Enterohaemorrhagic E. coli infection. Weigert stain showing fibrin ‘thrombi’ in glomerular capillaries in haemolytic uraemic syndrome. By courtesy of Dr. H.R. Powell
Pathogen E. coli strains
DiagnosisDirect detectionSerotyping
ProphylaxisExpositions prophylaxis
TherapyWater and electrolyte substitutionAntibiogram
Gram negative facultativeanaerobic rods
Enterobacteriaceae II.
GRAM NEGATIVE RODS
AEROBBordetellaBrucellaFrancisella
PseudomonasAcinetobacterLegionella
FACULTATIV ANAEROBHaemophilusPasteurella
Familia:EnterobacteriaceaeVibrionaceae
CardiobacteriumEikenellaKingellaActinobacillus
ANAEROBBacteroidesPrevotellaPorphyromonasFusobacterium
MICROAEROPHILCampylobacterHelicobacter
Enterobacteriaceae
Morphology: - Gram negative rods- pili(ex.: Klebsiella, Shigella)
Cultivation:easy, simple (Agar, Bloodagar) MediaDifferentiation: pathogenic-facultative pathogenic(Biochemical reactions)
a) Selectiv-Mediab) Differential-Mediac) Indicator-Media
Antigens and Virulence factors:O (cell-wall)H (Flagella)K (capsule)surface ProteinsPiliExotoxinsEndotoxin
Enterobacteriaceae
BACTERIAL GI TRACT INFECTIONSI. Type EnterotoxinHypersecretionSmall intestine
watery diarrhea
Vibrio choleraeEscherichia coli(ETEC)
II. TypeInflammationInvasion in MucosaLarge intestine
pus, blood, mucus in stool
ShigellaE. coli (EIEC) (EPEC, EHEC)SalmonellaYersinia enterocoliticaCampylobacter jejuniAeromonas sp.Vibrio parahaemolyticus
Clostridium difficileClostridium perfringens
III. TypePenetration,GeneralisationBacterium intracellularIleum
Typhus, Sepsis
Salmonella typhiS. paratyphi A, BYersinia enterocoliticaY. pseudotuberculosisCampylobacter fetus
Exogen, peroral Infection, faecal–oral transmission route
Enterobacteriaceae
Facultative pathogenesgenusEscherichia
Klebsiella GruppeEnterobacterEdwardsiellaCitrobacter
Proteus GruppeSerratiaProvidenciaMorganella
Obligate pathogens (genera)Escherichia coli
ETEC (enterotoxic)EPEC (enteropathogenic)EIEC (enteroinvasive)EHEC (enterohemorrhagic)EAggEC (enteroaggregativ)
ShigellaS. dysenteriaeS. flexneriS. boydiiS. sonnei
SalmonellaS. typhiS. paratyphi
YersiniaY. pestisY. pseudotuberculosisY. enterocolitica
Salmonellae
www.ltsa.frwww.about-salmonella.com
Salmonella sp.
Salmonella typhi, S. paratyphi A, B, C
Antigen structure of Salmonella typhigripsdb.dimdi.de
Obligate human pathogens
AntigensOH (flagella)superficial Vi Ag = capsule
Salmonella typhi, S. paratyphi A, B, C
PathogenesisSource of infectionsick, carriers; Contaminated food, drinking waterPortal of entrymouth gut blood Organs: spleen, liver, bile, bone-marrrow, kidneys, brainIleum: ulceration (bleeding, Perforation)
Clinical findings:Typhus abdominalisParatyphus
Please, learn the latin terms!The english enteric fever or typhoidfever does not tell, which bacteriumcaused the disease!
Salmonella typhi, S. paratyphi A, B, C
Figure 2. Flagellar stain of a Salmonellatyphi. Like E. coli, Salmonella are motile by means of peritrichous flagella. A close relative that causes enteric infections is the bacterium Shigella. Shigella is not motile, and therefore it can be differentiated from Salmonella on the basis of a motility test or a flagellar stain. (CDC)
Figure 1. Salmonella typhi, the agent of typhoid. Gram stain. (CDC)
www.textbookofbacteriology.net
Typhus abdominalis
Roseolenartiges, makulopapulöses Exanthem bei Typhus abdominalis gripsdb.dimdi.de
www.wrongdiagnosis.comRose spots on abdomen of a patient with typhoid fever due to the bacterium Salmonella typhi.
Rose spots on the chest of a patient with typhoid fever due to the bacterium Salmonella typhi. www.wrongdiagnosis.com
Fig. 4.37 Typhoid fever. Numerous ulcers of the small intestine overlying hyperplastic lymphoid follicles (Peyer’s patches). By courtesy of Dr. J. Newman.
Fig. 4.39 Typhoid fever. Mononuclear cells and red blood cells in the stool. Trichrome stain. By courtesy of Dr. H.L. DuPont.
Typhus abdominalisDiagnosisDirect detection (blood, stool, Urine)Selective mediaAntibody detection
(tube-Agglutination)
ProphylaxisExpositions prophylaxisImmune prophylaxis:1) Active oral immunisation with
Ty21, an apathogenic, attenuated strain
2) Parenteral injection with Vi capsule polysaccharideS. typhi-strain Type-2
TherapyAmpicillinTrimethoprimChloramphenicol
Carriers!!
„Typhoid Mary”
www.spiceisle.com
Salmonella - SalmonellosisUbiquitous: S. typhimurium, S. enteritidis etc.
Pathogen for birds, eggs, swine, cattle, mouse, rat and human
PathogenesisSource of infection: from infected animals, contaminated foodBacteria multiply in the food! Endotoxin free
Clinical finding:FOOD POISONING – Endotoxin effectNo bacterium multiplication in guts, self limited(Gastro)enteritis – bacteria can multiply in guts, type II. diarrhoea, not always self limited
Diagnosis: direct detection (stool, food)Prophylaxis: food and kitchen hygiene
Figure 21-3 Invasion of intestinal mucosa by Salmonella.
medmicrotyphus
www.idph.state.il.us
spacescience.comSalmonella sp.
www2.nphs.wales.nhs.uk
Salmonella enterica
www.textbookofbacteriology.net
Figure 3. Salmonella sp. after 24 hours growth on XLD agar.
www.textbookofbacteriology.net
www.textbookofbacteriology.net
Figure 4. Colonial growth Salmonella choleraesuissubsp. arizonae bacteria grown on a blood agar culture plate. Also known as Salmonella arizonae, it is a zoonotic bacterium that can infect humans, birds, reptiles, and other animals. (CDC)
www.chromagar.com
Rambach™ Agar For detection of Salmonella spp. •Salmonella - red•other bacteria - blue, violet, colourless, or inhibited.
wqc
.ariz
ona.
edu
Isolation of Salmonellafrom Environmental Samples
pathmicro.med.sc.edu
TSI Medium Identification
www.textbookofbacteriology.netSalmonella typhimurium HE agar
Enterobacteriaceae
Facultative pathogenesgenusEscherichia
Klebsiella groupEnterobacterEdwardsiellaCitrobacter
Proteus GroupSerratiaProvidenciaMorganella
Obligate pathogens (genera)Escherichia coli
ETEC (enterotoxisch)EPEC (enteropathogene)EIEC (enteroinvasive)EHEC (enterohemorrhagisch)EAggEC (enteroaggregativ)
ShigellaS. dysenteriaeS. flexneriS. boydiiS. sonnei
SalmonellaS. typhiS. paratyphi
YersiniaY. pestisY. pseudotuberculosisY. enterocolitica
Shigella
S. dysenteriae* 10 SerotypesS. flexneri* 6 SerotypesS. boydii 15 SerotypesS. sonnei
AntigenO
* Toxin
Shigella sonnei
Shigella
Virulence factorsExotoxincytotoxic (cell lysis!);Enterotoxic;Paralytic – letal activity
Fragment A, B (5) – Glycolipid
Inhibition of Proteinsynthesis – Binding andInactivation of 60s Ribosom subunit cell death
OMP (Ipa, Ics)Endotoxin - LPS
Pathogenicity – ID50: 100-200 BacteriaEntry and multiplication in Epithel cells:Invasion Plasmid Antigens – IpaIntercellular Spread – Ics
Pathogenesis, clinical findingsLocal InfectionEpithel necrosis, ulcerationinhibiting AbsorptionHUS!
Shigella
Medmicro
Shigella
mgc.ac.cn/VFs/Figures/Shigella
Shigella
Fig. 2: Shigella Passing Through the Mucous Membrane and …
… Invading Mucosal Epithelial Cells
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cbcm
d.ed
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Fig. 4.33 Shigellosis. Sigmoidoscopic view of colonic mucosa in a mild case of infection due to S. flexneri. Note the thin whitish exsudate, which is made up of fibrin and polymorphonuclearleucocytes. By courtesy of Dr. R.H. Gilman.
Fig. 4.34 Shigellosis. Sigmoidoscopic view of colonic mucosa in a fatal case of infection with S. dysenteriaetype 1 showing extensive pseudomembranous colitis. By courtesy of Dr. R.H. Gilman and Dr. F. Koster.
Fig. 4.18 Positive Serény test. Keratoconjunctivitis in the rabbit produced by the instillation of shigella microorganism. By courtesy of Dr. H.L. DuPont.
www.textbookofbacteriology.net
Shigella
DiagnosisDirect detection(from stool)
Differentiating –SelectiveMedia
Identification Serotyping
pathmicro.med.sc.edu
TSI Medium Identification
Shigella boydii colonies on blood agar
www.biologie.de
Appearance of Colonies on Salmonella-Shigella Agar
ww
w.rc
i.rut
gers
.edu
A. Klebsiella pneumoniae B. Escherichia coliKlebsiella pneumoniae & Escherichia coli are positive for acid production from fermentation of the carbohydrate(s) present.
C: Salmonella sp.
D: Proteus mirabilis
Both Salmonella sp. & Proteus mirabilis product hydrogen sulfide. E: Pseudomona aeruginosa
The
Pse
udom
onas
colo
nies
are
near
lyco
lorle
ss.
Shigella
ProphylaxisExpositions prophylaxis – Hygienic rules
TherapyAntibiogramTetracylin, Ampicillin, Chloramphenicol, Sumetrolim
Enterobacteriaceae
Facultative pathogenesgenusEscherichia
Klebsiella groupEnterobacterEdwardsiellaCitrobacter
Proteus GroupSerratiaProvidenciaMorganella
Obligate pathogens (genera)Escherichia coli
ETEC (enterotoxic)EPEC (enteropathogenic)EIEC (enteroinvasive)EHEC (enterohemorrhagic)EAggEC (enteroaggregativ)
ShigellaS. dysenteriaeS. flexneriS. boydiiS. sonnei
SalmonellaS. typhiS. paratyphi
YersiniaY. pestisY. pseudotuberculosisY. enterocolitica
Yersinia enterocolitica
Morphology Gram negative,bipolar rods
flagellae
ww
w.w
adsw
orth
.org
Yersinia enterocolitica www.ktl.fi
cultivationoptimum 28°C, motility 28°C
Y. enterocoliticaO:5,27 CIN-ag
www.szu.czBlood agar
AntigensO and H
Y. enterocoliticade.wikipedia.org
Figure 29-7 Pathogenesis of Y. enterocolitica.
Clinical findingEnterocolitisLymphadenitis mesenterica
DiagnosisDirect detectionSerologySerotyping
TherapyTetracyclinChloramphenicolSumetrolim
Yersinia pseudotuberculosis
MorphologyGram negative, bipolar rodsflagellae
Cultureeasy, grow 37°C and 20°Cmotility 20°C
PathogenicityPseudotuberculosis ofrodents
Source of infection:Sick animalsPortal of entry: mouth, mucosa Y. pseudotuberculosis
www.microbes-edu.org
Yersinia pseudotuberculosis
Clinical findingsLymphadenitis mesentericaSeptic-typhoid FormEnteritis
DiagnosisDirect detectionSerotyping – AgglutinationSerology
TherapyTetracyclin
Fig. 4.50 Yersinia infection. Gross specimen of ileum, showing superficial necrosis of the intestinal mucosa with several well-defined deep and superficial ulcers.
www.llnl.gov
Y. pseudotuberculosis
Gram negative facultativeanaerobic rods
Vibrionaceae
GRAM NEGATIVE RODS
AEROBBordetellaBrucellaFrancisella
PseudomonasAcinetobacterLegionella
FACULTATIVE ANAEROBHaemophilusPasteurella
Familia:EnterobacteriaceaeVibrionaceae
CardiobacteriumEikenellaKingellaActinobacillus
ANAEROBBacteroidesPrevotellaPorphyromonasFusobacterium
MICROAEROPHILCampylobacterHelicobacter
BACTERIAL GI TRACT INFECTIONSI. Type EnterotoxinHypersecretionSmall intestine
watery diarrhea
Vibrio choleraeEscherichia coli(ETEC)
II. TypeInflammationInvasion in MucosaLarge intestine
pus, blood, mucus in stool
ShigellaE. coli (EIEC) (EPEC, EHEC)SalmonellaYersinia enterocoliticaCampylobacter jejuniAeromonas sp.Vibrio parahaemolyticus
Clostridium difficileClostridium perfringens
III. TypePenetration,GeneralisationBacterium intracellularIleum
Typhus, Sepsis
Salmonella typhiS. paratyphi A, BYersinia enterocoliticaY. pseudotuberculosisCampylobacter fetus
Exogen, peroral Infection, faecal–oral transmission route
Gram negative facultative anaerobic rods(Positive Glucose fermentation)
Oxidase positive Oxidase negative
Vibrionaceae Aeromonadaceae
Vibrio Aeromonas
Enterobacteriaceae
EscherichiaKlebsiella
EnterobacterProteusSerratia
ProvidenciaMorganella
EdwardsiellaCitrobacter
Hafnia
SalmonellaShigellaYersinia
Facultativepathogenic
Obligatepathogenic
Plesiomonas
V. choleraeV. parahaemolyticusV. vulnificus
P. shigelloides A. hydrophila
VibrionaceaeSpecies Associated diseases
V. cholerae O1klassische & El Tor Cholera
V. cholerae O139 Cholera
V. parahaemolyticus Gastroenteritis
V. vulnificus Wound infection, sepsis
Non-agglutinable(NAG) vibrios Gastroenteritis (rarely)
R. Koch, 1883Morphology• Gr–, curved rods• Facultative anaerobesBiochemical reactionsGlukose OF ‡Motility +Catalase +Oxidase +Nitrate Reduction +
Vibrio cholerae
bepast.org
V. cholerae
Antigen structure, virulence factorsO (cell wall) - 138O1 & O139H flagellar (common)Fimbriae: A, B, CO1: Bio and Serotypes
V. cholerae
Vibrio cholerae. Leifson flagella stain (digitally colorized). CDC/Dr. William A. Clark
pathmicro.med.sc.edu
Bio- & Serotypes of V. cholerae O1
Medmicro
Virulence factors
Virulence factor Biologic effect
Cholera toxin Fluid & electrolytehypersecretion
Fimbriae Adhesion to mucus membrane
Accessory colonisation factor Adhesion to mucus membrane
Haemagglutination protease (mucinase)
Enteric inflammationdegradation of tight junctions
Siderophores Iron sequestration
Neuraminidase Toxin receptor up-regulation
V. cholerae
Pathogenesis – Obligate human pathogenSource of infection: 1. humans (sick) and carriers(incubation, constant carriers and reconvalescent carriers – via stool! – flies!)2. Contaminated food (sea food!) and drinking waterReservoir: Algae, Mussel, PlanktonsTransmission: Per oralPortal of entry: GI
Toxin building in small intestineNO DISSEMINATION!Clinical finding, disease: Cholera – due to Cholera toxin
Immunity: local IgA (IgG in blood!)
Adhaesion of V. cholerae to intestinal epithelium
TEM, ×16.000SEM, ×4.000
Medmicro ch 24
FIGURE 24-1 Pathophysiology of cholera.
textbookofbacteriology.net
Cholera toxin: mode of action
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1. 2.
3.
4.
Cholera Toxin and Pertussis Toxin
Cholera Pandemies• India, estuarine of Ganges• Intercontinental travels, trading, wars ⇒
seven pandemics from 1817• At present: 7th pandemic, V. EL Tor
– 1961: Asia– 70’s–80’s: Africa, Europe, Oceania– 1991: South-America
• 1992 : V. cholerae O139 „Bengal”– Rapid spread (Asia, Europe, USA)– No cross immunity with O1-strains– 8th pandemic?
7th Cholera Pandemy 1961
Cholera cases, WHO: 2000–2001
Cholera outbreaks
Cholera camp in Mozambique
Cholera clinic in Mozambique
Cholera: clinical picture• rice- - water diarrhoea
(25 L/day)• Dehydration• Haemoconcentration• Blood pH • Serum K+ , Na+
• Serum Glucose ↑• Shock• Letality
– Untreated• Classical: 60%• El Tor: 15–30%
– Treated: 1%
Rice-water diarrhoea
Baby before and afterrehydration
Cholera Beds
• Patients history!• specimen: stool• Direct microscopy:
dark field microscope
Diagnosis
Transport: Alkaline PeptonwaterCulture: TCBS medium
Diagnosis
IdentificationBiochemical Reactions
Serotyping (O1, O139)
Antibiogram
Diagnosis
V. cholerae
Prophylaxis of Cholera
Expositions prophylaxisClean drinking water! – and food hygiene and sewage water system – no mix with drink water!
Mass education, adhering to hygienic rulesIsolation; Quarantinetreating, disinfectingWater boilingFollow up carriersReport to WHO
• Immune prophylaxisVaccination
– Vaccine (against O1 ony)• Killed bacterium, parenteral• Killed bacterium + B-subunit Toxoid per os• Gene manipulated, attenuated V. cholerae per os
– Protection of 3–6 month, efficacy 50–60%– Travellers to endemic areas– WHO: false feeling of security (!)
Prevention of cholera: mass education of hygienic rules
Therapy of Cholera
Salt-sticks
Coke
Therapy of Cholera
• Fluid and electrolyte substitution– Intravenous– Per os Oral Rehydration Fluid
ORF• Glucose 20g/l• NaHCO3: 2,5 g/l• NaCl: 3,5 g/l• KCl: 1,5 g/l
• Antibiotic– Ciprofloxacin– Doxycycline
Peru
Bangladesh
Vibrio parahaemolyticus
www.city.niigata.niigata.jp
www.fehd.gov.hk
Gastroenteritis
Fig. 10.20 Cellulitis. Severe infection with bullous lesions due to V. vulnificus infection following immersion of leg in brackish water.
V. vulnificus
V. vulnificus
Fig. 10.21 Vibrio cellulitis. Haemorrhagic, bullouslesions of V. vulnificussepsis. By courtesy of Dr. J.R. Cantey
A. hydrophila P. shigelloides
Cellulitis Myonecrosis
A. hydrophila infection in fish
Gastroenteritis
Sea food
Natural water sources
web.umr.edu
Aeromonas hydrophila
www.buddycom.com
www.buddycom.comweb.umr.edu
Aeromonas hydrophila
Plesiomonas shigelloideshttp://www.vetmed.wisc.edu
Aeromonas hydrophila
Aeromonas hydrophila
To be continued…
Zakynthos, 2004
Microaerophilic Gram negative rods –
Campylobacter andHelicobacter
GRAM NEGATIVE RODS
AEROBBordetellaBrucellaFrancisella
PseudomonasAcinetobacterLegionella
FACULTATIVE ANAEROBHaemophilusPasteurella
Familia:EnterobacteriaceaeVibrionaceae
CardiobacteriumEikenellaKingellaActinobacillus
ANAEROBBacteroidesPrevotellaPorphyromonasFusobacterium
MICROAEROPHILCampylobacterHelicobacter
BACTERIAL GI TRACT INFECTIONSI. Type EnterotoxinHypersecretionSmall intestine
watery diarrhea
Vibrio choleraeEscherichia coli(ETEC)
II. TypeInflammationInvasion in MucosaLarge intestine
pus, blood, mucus in stool
ShigellaE. coli (EIEC) (EPEC, EHEC)SalmonellaYersinia enterocoliticaCampylobacter jejuniAeromonas sp.Vibrio parahaemolyticus
Clostridium difficileClostridium perfringens
III. TypePenetration,GeneralisationBacterium intracellularIleum
Typhus, Sepsis
Salmonella typhiS. paratyphi A, BYersinia enterocoliticaY. pseudotuberculosisCampylobacter fetus
Exogen, peroral Infection, faecal–oral transmission route
Spiral formed & curvedGram-negative bacteria
Spirillaceae
Campylobacter Helicobacter Spirillum
C. jejuni H. pylori S. minus
Most important species of Campylobacter genus
Species Reservoir Diseases Frequency
C. C. jejunijejuni Poultry, pig, cattle, rabbit
Gastroenteritis, sepsis, meningitis, Guillan-Barré
Frequent
C. coli Pig, poultry, cattle, sheep
Sepsis, gastroenteritis, meningitis
Uncommon
C. fetus Cattle, sheepSepsis, gastroenteritis, meningitis
Uncommon
C. lari Poultry, pig, cat, monkey, horse
Gastroenteritis, sepsis Rare
C. upsalensis Dog, cat Gastroenteritis, sepsis, abscess ?
Campylobacter
MorphologyGram negative curved rods (0,3–0,6 μm)
Campylobacter
Polar flagellum
Transmission electron micrographs of Campylobacter jejuni, negatively stained to enhance contrast.
www.wadsworth.org
www.shef.ac.uk Campylobacter jejuni
www.indigo.com
Campylobacter jejuni
CultureMicroaerophilic
5–7% O25–10% CO2
Thermophilic: 42ºC
Campylobacter
Campy-blood-agarmedinfo.ufl.edu
www.biomerieux.com
Special media
Campylobacter C. jejuni, SEM
C. jejuni, SEM
Biochemical reactionsNon-fermenting • Catalase +, Oxidase +• Nitrate reduction +• Antigen Structure
– O, H, K (Serotyping)
Virulence factors• flagellum ⇒ motility• Adhaesion Factors• Invasion Factors (?)• Cytotoxin• C. fetus: S-Protein ⇒ inhibition of binding of C3b ⇒
antiphagocytic effect• LPS
Complication:• Guillan-Barré SyndromeSimilar structure: LPS-core and glycosphingolipids of
Gangliosids (GM1, GM2) ⇒Antibodies against GM1 ⇒Autoimmun process ⇒ Demyelinisation
Campylobacter
C. coli & Guillan-Barré syndrome
Epidemiology
• Zoonotic infection!• Source of infection:
contaminated food & waterInsufficient heat on meat• Human to human: Faecal-oral
route (children). Rarely• ID: 500 (low)• Very common (in developing
countries 80% of diarrhealdiseases)
Campylobacteriosis: Clinical picture
• Incubation: 1–2 days• Bloody diarrhoea• Fever• Abdominal pain, cramps• Spontaneous healing:
within 1–7 days• Complications
– Prolonged course– Systemic infection– Reactive arthritis– Guillan-Barré syndrome
Diagnosis of Campylobacter Infections
Campylo-agarculture
Biochemical identification
• Sample– Faeces– Blood culture, CSF– Food
• Culture (microaerophilic, thermophilic)• Identification• Antibiotic susceptibility test
Therapy & Prevention of Campylobacter Infections
• Supportive (water, electrolytes)• Antibiotic therapy
– Gastroenteritis• Erythromycin, Doxycycline, Ciprofloxacin,
Amoxicillin/clavulanic acid– Systemic infection
• Carbapenem, Aminoglycoside, Chloramphenicol
• Prevention: food hygiene
Helicobacter pyloriMorphology• Gram negative, spiral-
formed rod
Polar flagellae: Motility
Culture• MicroaerophilicBiochemical reactions• Non-fermenting• Catalase +• Oxidase +• Urease + (!)
H. pylori
Virulence factors of H. pylori• Adhaesins (HOP)• Flagellae (Motility)• Mucinase, phospholipase• Urease activity• Vacuolating cytotoxin• Protein CagA
Translocation viaType IV. Secretion-systemchanging cytoskeletonIl-8, Il-1, TNFα Stimulation
Urease positive
Cytotoxic effect in HeLa cells
Epidemiology and clinical findings ofH. pylori Infections
Epidemiology• Common worldwide• Reservoir: humans• Transmission
– Faecal-oral– Oro-oral (saliva)– Endoscope!
Clinical pictureAcute GastritisChronic-active GastritisGastroduodenal UlcusTumor
H. pylori & peptic ulcer
Chronic gastritis
Duodenal ulcer
H. pylori on gastric mucosa, SEM
H. pylori histology, silver impregnation
H. pylori & gastric carcinoma
Antral adenocarcinomagastroscopic finding
Gastric adenocarcinoma withliver metastasis & ascites
Diagnosis of H. pylori
• direct detection of Helicobacter Antigen in stool sample• biopsy: Histopathology, culture, molecular biology (PCR)• radioactive Urea expiration test• serology: AB detection
Radioactive Urea expiration test
Microbiological Diagnosis of H. pylori
H. pylori culture
Biochemical identification
H. pylori ELISA (IgG, IgA)
H. pylori Western blot
culture –Biopsy Material
antibodies – Blood serum
H. pylori Eradication
• Combinations - Therapy with– Proton pump inhibitors– Antibiotics
• Clarithromycin + Metronidazole• Amoxicillin + Metronidazole• Doxycycline + Metronidazole
– Eradication: 90%
THE END
Santorini, 2009
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