Transcript Oral Infections

Oral Infections
Acute pseudomembranous
candidosis
Actinomycosis
Acute
erythematous
candidosis
Herpes simplex
Dr Ian Douglas
University of Sheffield
Acquisition of oral flora
• At birth oral cavity is sterile
• Most species acquired during the
first 2 years of life
• Flora mainly acquired from mother
– its all in a kiss!
Acquisition of mutans
streptococci
infectivity
window
tooth emergence
molars
6
12
18
24
age (months)
30
36
Plaque -in vivo biofilm
Dental caries
Stephan Curve
pH in
plaque
7
6
Normal
Snacking
5
4
pulses
3
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Hours
Prevalence of some
bacteria in caries
% viable count
Progressive Non-progressive
mutans
10
3
S.sanguis
6
9
S.oralis
4
5
Lactobacillus 1
0
Veillonella
11
9
Actinomyces
29
33
Mechanical removal of plaque?
Toothbrush
bristle
Topical passive immunisation
•Anti S.mutans s-IgA
cloned into tobacco
•3 week application
eliminated oral S.mutans
Replacement Therapy -
Superbugs
bacteriocin
S
bacteriocin
bacteriocin
•Potent bacteriocin
producer
•Stable LDH-deficient
mutant
• Produces ethanol &
other acids
•Imported
adh gene
Destructive Periodontitis
Attacment loss (mm)
Disease Progression
10
9
8
7
6
5
4
3
2
1
0
20
35
45
55
Age (years)
Association of organisms
with disease
Disease
Health
A.odontolyticus
V.parvula
S.mitis
S.oralis
S.sanguis
Pr.intermedia
At.actinomycetemcomitans
Pr.nigrescens
F.nucleatum
Pt.micros
C.rectus
P.gingivalis
Ta.forsythus
T.denticola
Periodontal species detected
by 16srRNA
• Estimate 415
species
•~40% were novel
phylotypes
•Detected in at
least four diseased
subjects, but not in
healthy subjects
Paster B J Bact 2001;
183; 3770-3783
Deferribacteres
Spirochaetes
Fusobacterium animalis
Atopobium parvulum
Atopobium rimae
Eubacterium sp.
Megasphaera sp.
Abiotrophia adiacens
Catonella morbi
Dialister pneumonsintes
Eubacterium saphenum
Filifactor alocis
Gemella haemolysans
Selenomonas sp.
Streptococcus constellatus
Desulfobulbus sp. R004
Campylobacter gracilis
Campylobacter rectus
Haemophilus parainfluenzae
Bacteroides forsythus
Prevotella tannerae
Porphyromonas endodontalis
Porphyromonas gingivalis
Periapical disease
Bacteria associated with
endodontic treatment failure
Species
E.faecalis
S.anginosus
S.constellatus
S.intermedius
Pept.micros
A.israelii
Prop.acnes
F.nucleatum
B.gracilis
No.cases
9
2
1
1
2
3
1
1
3
Spread of infection from
the tooth
Examples of oral abscesses
Bacterial genera in
periapical abscesses
Anaerobes
Gram-negative
Prevotella*
Porphyromonas*
Fusobacterium*
Campylobacter*
Veillonella
Bacteroides
Treponema
Gram-positive
Peptostreptococcus*
Eubacterium*
Propionibacterium
Facultatives
Gram-negative
Eikenella
Capnocytophaga
Haemophilus
Gram-positive
Streptococcus*
Enterococcus
Lactobacillus
Actinomyces
* most
frequently
recovered
Antibiotic sensitivity among
oral anaerobes
Kuriyama et al 2001
Prevotella
Porphyro
Fusobact
Ampicillin
10
83
83
Amp/Sulbact
100
100
100
Cefazolin
38
83
94
Cefotaxime
62
100
100
Imipenem
100
100
100
Clindamycin
100
100
8
Erythromycin
81
94
100
Minocycline
81
100
100
Metronidazole
100
100
100
ß-lacatmase in Prevotella
isolates
Species
% positive
P.intermedia
17
P.melaninogenica
78
P.oralis
50
P.buccae
25
Summary
• Oral infections are polymicrobial
• Generally caused by endogenous
commensal species
• There is relatively little microbial
specificity for the different types
of lesion (except dental caries?)
• Some oral infections pose treatment
problems due to antimicrobial
resistance