NonSporing Anaerobes Introduction u Anaerobes n Bacteria that
Non-Sporing Anaerobes
Introduction u Anaerobes n Bacteria that lack the enzymes superoxide dismutase, peroxidase and/or catalase, makes them susceptible to oxygen derived free radicals n Obtain energy from fermentation process 2
(1) Obligate Aerobes - E. g. Pseudomonas (2) Obligate (strict) Anaerobes - E. g Bacteriodes (3) Facultative anaerobes - E. g. Staphylococcus (4) Microaerophilic organisms - E. g. Campylobacter 3
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Classification of Non - sporing Anaerobes Gram -ve bacilli Gram +ve bacilli Bacteroides Prevotella Porphyromonas Fusobacterium Leptotrichia Eubacterium Propionibacterium Lactobacillus Mobiluncus Bifidobacterium Actinomyces Cocci Spirochetes Peptococci (gram +ve) Treponema Peptostreptococci (gram Borrelia +ve) Veillonella (gram –ve) 5
Anaerobic cocci u Peptococcus & Peptostreptococcus – usually produce mixed infections (Polymicrobial infection, odor) n n n Puerperal sepsis & other genital infections Wound infections Gangrenous appendicitis UTI Osteomyelitis Abscesses in brain, lungs & other internal organs 6
Peptostreptococcus 7
Gram positive anaerobic rods u Bifidobacterium – pleomorphic bacilli showing true & false branching u Mobiluncus – motile, curved, gram variable bacilli 8
u Lactobacillus (Doderlein’s bacilli) – normal flora in mouth, intestine & forms vaginal microbiota 9
Probiotics and biotherapeutics u The term probiotic is currently used to name ingested microorganisms associated with beneficial effects to humans and animals. Food production u Some Lactobacillus species are used as starter cultures in industry for controlled fermentation in the production of yogurt, cheese, pickles, beer, wine, cider, cocoa, and other fermented foods 10
Pathogenicity of Gram positive anaerobic rods Propionibacterium acne Acne Propionibacterium propionicum Cervico - fascial, Pulmonary abscess Mobiluncus Bacterial Vaginosis along with Gardenerella vaginalis Periodonti tis Eubacteri um 11
GRAM NEGATIVE ANAEROBIC BACILLI u Bacteroides n n n Most common anaerobes isolated from clinical specimens Pleomorphic, capsulated Grows on Brain Heart Infusion agar in 10% CO 2 12
u Prevotella & Porphyromonas – pigmented anaerobes n Porphyromonas black or brown color colonies (due to hemin derivative) u Colonies & even dressings from wounds infected with this bacillus gives a characteristic red fluorescence when exposed to UV light. u 13
Pathogenicities of Gram negative anaerobic bacilli Bacteroides fragilis Brain abscess, intra abdominal abscess, infections of female genitalia, cellulitis, diabetic ulcer, septicaemia Prevotella melaninogenica Lung or liver abscess, empyema, pelvic infections in females, breast abscess, wound infections Porphyromonas Dental root canal infections, periodontal disease Fusobacterium necrophorum Aspiration pneumonia, lung/ liver abscess, oral infections, chronic sinusitis, abdominal infections Fusobacterium nucleatum 14
Laboratory Diagnosis 15
Laboratory Diagnosis u Specimen - Deep aspirates, tissue bits u Collection & transport – n n n 16 Pre-reduced transport medium Gassed out vials Needle & syringe with rubber bunk
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Laboratory Diagnosis u Microscopy – Gram stain: many pus cells, variety of different micro-organisms u Culture media n n n u Blood agar Phenyl ethyl alcohol agar (PEA) Kanamycin / vancomycin BA Thioglycollate broth RCM Culture methods – Anaerobic jar, Bactec (anaerobic blood culture) 18 Gaspak,
Anaerobic blood Hungate tube culture vials 19
Robertson cooked meat media (RCM) It also contains -glutathione, a reducing substance -meat pieces -broth Saccharolytic Proteolytic 20
09/03/2008 21 Dr Ekta Chourasia, Microbiology
09/03/2008 22 Dr Ekta Chourasia, Microbiology
Anerobic gas chamber 09/03/2008 23 Dr Ekta Chourasia, Microbiology
u All cultures must be incubated for 7 -10 days as most of the anaerobes are slow growing. u Detection of metabolic products – gas liquid chromatography (GLC) can be directly carried out on pus & other clinical specimens to detect metabolic products like butyric & propionic acid. 24
Treatment & Prevention u Surgical – n n n u Drainage of pus from abscess Wound debridement Curettage & removal of necrotic tissues Antibiotics – n n Metronidazole Penicillin Clindamycin Cefamycin 25
Ludwig's Angina u Named after Karl Friedrich Willhelm von Ludwig, Ludwig's angina is characterized as a rapidly progressive gangrenous cellulitis of the soft tissues of the neck and floor of the mouth.
u Patients with immunocompromising conditions, such as HIV, diabetes, transplant recipients, and alcoholics u Polymicrobial infection occurs in over 50% of cases ü u Staphylococcus, species Streptococcus, and Bacteroides Atypical organisms. : Pseudomonas, Escherichia coli, Klebsiella, Enterococcus faecalis, Candida, and Clostridium.
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