Non sporing anaerobes, Predesposing factors, classification of organism, lab diagnosis
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Language: en
Added: Nov 02, 2015
Slides: 22 pages
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Expert- Dr Ovhal sir Nonsporing Anaerobes
Introduction Anaerobes Are bacteria which are able to live in relative or total absence of Oxygen. Nonsporing anaerobes Classified on the basis of DNA base composition and analysis of fatty acid product metabolism.
Cultural characteristics- Grow in absence of molecular oxygen Optimum temp- 37˚C Optimum pH- 7.0-7.4 Incubation period- 48 hrs or more Grow well on freshly prepared/pre-reduced BA P.melaninogenicus
Transport- Protect specimen from lethal effect of O2 Swab- Stuart media/ RCM Aspiration- material is injected through rubber stopper in bulb containing CO 2 Syringe- needle is inserted in a sterile rubber stopper after expulsion of air bubble Blood- BHI broth/ thioglycolate broth
Processing of specimen Gross examination Black color Foul smelling Direct microscopy Gram stain Polymicrobial picture Lactobacillus spp. Bacteroids spp. Fusobacterium spp.
Culture Plain freshly prepared blood agar Neomycin blood agar Neomycin- Kanamycin blood agar Phenyl ethyl alcohol blood agar Kanamycin vancomycin blood agar (for GNBs) After inoculation, plates are incubated anaerobically in McIntosh- Filde’s jar Gas pack jar Anaerobic glove box
McIntosh Filde’s Jar Gaspak Jar Anaerobic glove box
Ultraviolet examination- Bright red fluorescence in case of P. melaninogenica . Rapid Identification with Gentamicin and metronidazole disc Rapid identification by biochemical tests API ( Indole , urea, gelatin, esculin , catalase ) Minitek BBL Gas liquid chromatography
Detection of antigen Co-agglutination Direct immunofluorescence Agglutination Haemagglutination PAGE ELISA
Antibiotic susceptibility testing Routine is unnecessary Serious infections ( endocarditis , brain abscess etc) Methods Broth dilution Agar dilution Broth disc test Disc diffusion
Antibiotics commonly prescribed Penicillin Tetracycline Chloramphenicol Clindamycin Metronidazole (DOC) Co- trimoxazole Amoxyclav Ampicillin / sulbactam In some infections surgical interventions are needed.