- Gram (-), small, slender rod usually straight but may be slightly curved.
- Motile with 1 to 3 polar flagella
- Nosporeforming; non encapsulated
- Stains readily with aniline dyes
- Other strains have abundant polysaccharide capsule
- Present in small numbers in normal intestinal flora and in skin.
- Give rise to blue-green pus
- Aerobic; some strains anaerobic
- Requires an optimum growth temperature of 37oC for 24 hrs incubation period.
- Colonies non-pigmented, large, soft, smooth, spreading and grayish in color.
- Killed by heating at 55oC for 1 hour
- Resistant to penicillin and most broad spectrum antibiotics
- Sensitive to polymyxin B, neomycin, oxytetracycline and streptomycin
Pathology and Symptomatology
- Pulmonary infections
- Swimmer’s Ear
- Burn infections (localized vascular damage, tissue necrosis and bacteremia)
- Gastrointestinal and urinary infections
- Eye, central nervous system and musculoskeletal system infections
- Skin lesion which is initially seen as erythematous vesicles that progresses to hemorrhage, necrosis and ulceration.
- For superficial skin lesions – topical Polymyxin B ointment
- For eye infections – strong solutions of polymyxin and streptomycin
- For middle ear infections – polymyxin b and streptomycin solutions; 0.5 to 1% acetic acid as alternative drugs
- For generalized forms of disease multiple drug therapy is recommended.
- 0.5% silver nitrate solution in continuously soaked dressings will reduce the total amount of secondary infection.
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