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‫بسم هللا الرحمن الرحيم‬
NON-SPORING
ANAEROBES
Prof. Khalifa Sifaw Ghenghesh
Part of the Normal Microbial Flora
• In the mouth and oropharynx,
gastrointestinal tract and female genital
tract of healthy individuals.
• Gram+ve and Gram – ve cocci, rods and
filaments, as well as spiral forms.
Wide Variety of Infections
• Wound infections
• Periodontal disease
Most infections are of endogenous
origin and polymicrobial (exception >
clostridia)
Infections in damaged and necrotic
tissues, or in the immunocompromised.
Some clinical signs and indicators of non-clostridial
anaerobic infections
------------------------------------------------------------------Foul-smelling pus, discharge or lesion
Production of a large amount of pus (abscess
formation)
Proximal of lesion to mucosal surface or portal of
entry
Failure to isolate organism from pus (sterile pus)
Infection associated with necrotic tissue
Deep abscess
Gas formation in tissues
Failure to respond to conventional antimicrobial therapy
Pus which shows red fluorescence under UV light
Detection of “sulphur granules” in pus (actinomycosis)
Infection of human or animal wound bite
Gram-negative bacteraemia
Septic thrombophlebitis
Polymicrobial Flora
Mixed infections varies according the site
affected.
2-12 species or more are involved.
May include strict and facultative
anaerobes and microaerophilic
organisms.
Frequently comprise mixtures of Gram
—ve rods (e.g. Bacteroides, Prevotella
and Fusobacterium species) and Gram+ve
cocci (peptostreptococci or streptococci
or both)
Non-Sporing Gram-Negative Rods
Fusobacterium species
• Oral origin (mainly)
• Colonize the mucous membranes of
humans and animals
• Commensals of upper respiratory and
gastrointestinal tracts.
• Fusobacterium nucleatum
Leptotrichia species
• Leptotrichia buccalis
• “Vincent’s gingivitis”
Bacteroides species and Related Gram —ve rods.
3 Groups:
Saccharolytic group >> Most important:
• Bacteroides fragilis (group)
• Intrabdominal and soft tissue infections below
the waist
Moderately Saccharolytic group
• Prevotella melaninogenica
Asaccharolytic group
• Porphyromonas asaccharolytica
• Porphyromonas gingivalis
• Periodontitis
Bacteroides fragilis ssp. fragilis
cultured in blood agar medium for 48 hours.
Bacteroides fragilis
Fusobacterium sp.
Gram-Positive Anaerobic Cocci
Genus: Peptostreptococcus
• P. asaccharolyticus
• P. vaginalis
Infections in various parts of
the body
• Abscesses
Types of Infection and Clinical Specimens from
which Anaerobic Gram+ve Cocci are Isolated
------------------------------------------------------------------Blood cultures
Central nervous system (including brain abscesses)
Head and neck infections (including ear)
Dental abscesses and infected root canal
Periodontal diseases
Human and animal bites
Pleural infections
Abdominal infections
Genito-urinary tract infections
Decubitus ulcers
Foot ulcers
Osteomyelitis
-------------------------------------------------------------------
Gram-Negative Anaerobic Cocci
Genus: Veillonella
• Normal flora of GIT
• A regular component of
supragingival plaque and the
tongue microflora
• A minor component of mixed
anaerobic infection
Non-Sporing Gram-Positive Rods
Present in significant numbers in
normal flora of the mouth, skin, GI
and female genito-urinary tracts
Propionibacterium
Bifidobacterium
Lactobacillus
Actinomyces
Eubacterium
Infection of the lachrymal canal
(lachrymal canaliculitis)
Some species are found in acne
Occasionally isolated in infective
endocarditis and infection
associated with implaned
prostheses
Spiral-Shaped, Motile organisms
Several Treponema species found
in the mouth
Mixed anaerobic infections
• Acute necrotizing ulcerative
gingivitis
Laboratory Diagnosis
Adequate clinical specimens are
collected (preferably under reducing
conditions) and rapidly transported to
bacteriology laboratory.
Microscopical examination
Cultured on proper media and under
anaerobic conditions
Gas-liquid chromatography
• Direct on pus and other clinical materials
Treatment
Surgical
• Drainage of pus from abscess,
debridement, curettage and removal
of necrotic tissue
Antibiotics
• Penicillin, Metronidazole