Gram (-) Non-motile Oxidase (+) Ferments glucose Most are susceptible to penicillin Catalase (+) except P. bettyae and P.caballi Reduce nitrate to nitrite P. multocida Disease association Focal soft tissue infection Respiratory disease Systemic disease LIVER CIRRHOSIS risk factor for systemic disease Characteristic Gram Stain Coccobacilli; frequent bipolar staining BAP Convex, smooth, gray, nonhemolytic, some …
Eikenella corrodens Methylobacterium Normal flora of human + – Spectrum of Diseaseand Infections Human bite wound infection Bacteremia and peritonitis in patients undergoing chronicambulatory peritoneal dialysis Gram Staining Slender, medium lengthgram (-) straight rod with rounded ends. Short medium-lengthgram (-) bacillus vacuolated, pale staining, may resistdecolorization Colonial appearance and characteristic Medium: BA Hallmark characteristic: …
Vibrio Motile (monotrichous) – SHOOTING STAR MOTILITY Oxidase (+), except for V. metschnikovii Halophilic except V. cholerae and V. mimicus LOA = ++- 0129 Susceptible vs. Aeromonas (R) Vibrio cholerae Agent of cholera Hallmark: rice watery stools (caused by cholera toxin) Somatic antigens – O1 & O139 Associated with V. cholerae envelope Positive markers for …
P. aeruginosa Disease association Primary cause of pneumonia in Cystic Fibrosis patients. Swimmer’s ears – contact lens infection jacuzzi hot tub syndrome erythema gangrenosum Virulence Factor Exotoxin A – most important Hemolysi ns Pili Alginate – mucoid Pyocyanin – specific Biofilm production Other Characteristic Appearance on BAP Spreading and flat; serrated edges, silver metallic sheen, …
Non-spore forming Facultatively anaerobes Glucose fermenters Oxidase (-) (exc. Plesiomonas) Catalase (+) (exc. Shigella dysenteriae) Commensal flora except Salmonella, Shigella, Yersinia (true pathogen) Nonencapsulated except (Klebsiella & Enterobacter) E. coli Primary marker for fecal contamination in water Disease Association Most common cause of nosocomial infections E. coli BIOTYPES Meningitis/sepsis-associated E. coli Infection Meningitis Virulence Factor …
Gram (+) Branching Partially acid-fast Nocardia Characteristics Beaded appearance Strictly aerobic Presence of DAP Produces Nocobactin – ironchelating compound Urease (+) Disease association Cutaneous infection Actinomycotic mycetoma Nocardia brasiliensis – most common cause of cutaneous infection and actinomycotic mycetoma. Nocardia asteroides – causes pulmonary infection Organism Casein Hydrolysis Nocardia brasilisiensis + Nocardia asteroides – Rhodococcus …
gram variable / gram (-) beta-hemolytic (HBT agar) / nonhemolytic (BAP) causes bacterial vaginosis Causes Bacterial Vaginosis Gardnerella vaginalis Prevotella spp. Peptostreptococcus spp. Porphyromonas spp. Mobiluncus spp. Mycoplasma hominis NUGENT SCORING SYSTEM – most accurate means of diagnosing bacterial vaginosis than culture NUGENT SCORING SYSTEM Lactobacillus morphotypes (boxy, gram (+) bacilli Gardnerella & Bacteroides (pleomorphic, …
Gram (+) bacilli Catalase (-) Non-branching H2S (+) in TSI Erysipelothrix rhusiopathiae Disease Association Erysipeloid bacteremia cutaneous infection Colony Appearance on BAP Large, rough, or small, smooth and translucent Shows alpha-hemolysis after prolonged incubation Identification Test-tube brush-like pattern in gelatin stab culture.
Gram (+) bacilli Catalase (+) Non-spore formin Non-branching Corynebacterium diphtheriae Virulence Factors Diptheria Toxin blocks protein synthesis causes demyelinating peripheral neuritis Bacteria is infected by lysogenic Betaphage TONSIL / PHARYNX – most common site of infection. Disease Association Respiratory Diphtheria – development of pseudomembrane (gray to white) Cutaneous Diphtheria – non healing ulcers (dirty gray) …
Aerobic and facultatively anaerobic Gram (+) Catalase (+) Spore-forming bacilli B. anthracis characteristics non-motile “bamboo rod” appearance Produces endospores Appearance in 5% SBA: Medusa head Ground glass appearance Beaten egg whites In MHA: String of Pearls Virulence factors Protective Antigen – facilitates transport of two other protein into the cell. Edema factor (adenylate cyclase) – …
