non fermenting GN

gen characteristics of nonfermenters

* saccharolytic or asaccharolytic
* long thin GN rod or ccb
* mostly ox pos
* TSI is K/K
* moist environments (soil, water, plants, decaying vegetation)
* prefer aerobic environment
* resistant to multiple classes of antibiotics

what infections are these bacteria typically isolated in?

septicemia, meningitis, osteomyelitis, wound infections

pseudomonas spp

* ubiquitous; some ppl’s skin normal flora
* pools, hot tubs, catheters, humidifiers in hospitals

clinical infections - p. aeruginosa

* leading cause of nosocomial RTIs
* wound infections/burn pts
* pulm infections ==(CF)==
* nosocomial UTIs, bacteremia
* endocarditis
* eye infections
* ear infections ==(swimmer’s ear)==
* skin infections (hot tub folliculitis)

p. aeruginosa virulence factors

* endotoxins, motility, pili, capsule, phospholipases
* exotoxins: protease, hemolysin, lecithinase, elastase, DNase
* exotoxin A blocks protein synthesis

p. aeruginosa morphology

* GNR
* spreading colonies (mucoid in CF pts), beta hemolytic
* metallic sheen on BAP, NLF on MAC
* blue green pigment produced
* grape like/tortilla chip odor

cetrimide agar

* nutritive
* 0.1% cetrimide
* cetyl trimethyl ammonium bromide: inhibits bacteria other than p. aeruginosa
* enhances production of fluorescent pigments

p. aeruginosa biochemicals

* ox pos, cat pos
* nitrate pos
* oxidizes carbs
* ADH pos
* citrate pos
* growth 42C (differs from other in fluoro group)

p. aeruginosa AST

* kanamycin R, carbenicillin S
* opposite for fluorescens/putida

CLSI p. aeruginosa

* presumptive: ox pos, indole neg
* additional: fruity odor of grapes
* notes: strong beta hemolysis

p. fluorescens and putida

* other fluoros
* make pyoverdin (not pyocyanin)
* ==no growth at 42C==
* neg nitrate
* low virulence
* infections: UTIs, post op abscesses, empyema, septic arthritis, wound infections

p. stutzeri

* rare isolate/pathogen
* dry, wrinkled, tough, adherent, yellow/brown with age
* confused with b. pseudomallei
* BICH:
* nitrate pos, ox pos
* ==neg ADH, gelatinase==
* produce acid from glucose not lactose

acinetobacter spp

* second most common isolate of these organisms
* normal flora in 25% adults
* hospitals (vents, humidifiers, catheters)
* UTI, pneumonia, endocarditis, septicemia, meningitis, wounds, eye infections

acinetobacter morphology appearance

* GN ccb: large diplococci similar to neisseria, moraxella
* difficult to decolorize
* varies on BAP: gray to white, yellow to tan, beta/gamma hemolytic
* NLF but can appear pink on MAC from oxidation of lactose with aging (not as pink as true LF)

acinetobacter biochemicals

* strict aerobes
* ==ox neg==, cat pos
* non motile

a. baumanii

* saccharolytic
* resistant to a lot of antibiotics
* CRAB: carbapenemase resistant a. baumanii (isolate pt)

a. lwoffi

* asaccharolytic
* less virulent, more often contaminant or colonizer

stenotrophomonas maltophila

* third most common isolate of these organisms
* water, sewage, plant materials, hospital environment
* pneumonia, endocarditis (surgery/IV drug users), bacteremia, wound infections
* resistant to multiple antimicrobials (S to SXT)

s. maltophilia morphology

* slight odor of ammonia
* pale yellow on BAP (sometimes green with aging)
* NLF on MAC

s. maltophilia biochemicals

* ==ox neg,== cat pos
* motile
* pos DNase, esculin, LDC, gelatin, ONPG
* strong oxidizer of maltose

b. cepacia

* nosocomial pathogen: hospital environment (fluids, anesthetics, nebulizers, detergents, disinfectants)
* pneumonia in CF pts
* endocarditis, UTIs, osteomyelitis, dermatitis, wound infections

b. cepacia morphology

* opaque, glistening
* NLF on MAC: may appear pink from strong lactose oxidation after aging
* earthy odor

OFPBL agar

* ox-ferm, polymixin B, bactracin, lactose
* bromthymol blue
* b. cepacia looks yellow from acidic end products (lactose metabolism)

BC agar

* CV, bile salts, ticarcillin, polymixin B, pyruvate
* phenol red
* b. cepacia looks pink/red from alkaline end products (pyruvate metabolism)

b. cepacia biochemicals

* slow ox pos
* motile
* LDC pos
* ODC neg
* oxidizes glu, mal, lac, mannitol

b. mallei

* glanders: disease in horses, transmitted via contact with infected animals (zoonotic)
* severe suppurative or acute pulm infections
* 1 case of human disease (lab accident)
* potential bioterrorism agent

b. mallei biochemicals

* V MAC, slow grower on BAP, non pigmented
* ==non motile==
* slow oxidizer (not xylose/sucrose)
* ADH pos
* nitrate pos
* ox V

b. pseudomallei

* SE asia, north aus, mexico
* melioidosis: aggressive pulm disease with septicemia, pneumonia; latent infections can relapse
* ingestion, inhalation, inoculation
* tier 1 select agent, agent of bioterrorism

b. pseudomallei morphology

wrinkled colonies (differentiate from p. stutzeri)

b. pseudomallei biochemicals

* putrid (later earthy odor)
* motile
* nitrate, ==gelatinase, ADH pos==
* 42C growth
* oxidizes carbs

where is moraxella found?

* normal flora of mucous membranes
* isolated from resp tract, urinary tract, eye but rarely cause disease

moraxella ID

* ox pos
* asaccharolytic
* strict aerobes, slow growers
* non motile GN ccb (only catarrhalis is cc)

m. nonliquefaciens

* neg gelatin, urease, PAD, no MAC growth
* bacteremia, keratitis, endophthalmitis

m. osloensis

like nonliquefaciens but can acidify etoh and produce alk rxn in acetate medium

m. atlantae

* MAC growth, will pit any agar
* neg gelatin, PAD, nitrate

m. lacunata

* unable to grow on MAC
* gelatin pos
* urease neg
* PAD V
* conjunctivitis

alcaligenes and achromobacter

* divided into asaccharolytic and saccharolytic
* found in water (pools, tap)
* hospital pts (urine, stool, sputum, wound, blood)

alcaligenes and achromobacter ID

* ox pos
* OF media: no oxidation with blue at top
* motile
* nitrate pos
* neg indole, esculin, gelatin
* some a. faecalis have fruity green apple odor

flavobacteriaceae

* ubiquitous (soil/water)
* contams of hospital equipment = nosocomial

flavobacteriaceae ID

* nonmotile
* yellow pigment, can turn BAP lav/green color
* fruity odor (juicy fruit)
* no/poor growth on MAC
* pos: ox, DNase, gelatin, indole (w)

chryseobacterium indologenes

* most frequently isolated species
* nosocomial: bacteremia, ocular infections

elizabethkingia meningosepticum

* cause of most flavo-related diseases
* NB meningitis, septicemia (preemies)
* pneumonia, endocarditis, bacteremia, meningitis

chromobacterium violaceum

* violet colored pigment (violacein)
* opportunistic; tropical and subtropical climates in soil, water
* skin lesion is portal of entry

methylobacterium

* bacteremia, perionitis, synovitis, skin ulcers
* slow grower 4-5days; grow on fungal media, no MAC growth, prefer 25-35C
* large vacuolated pleomorphic rods
* use methanol as sole source of carbon/energy

roseomonas

* pink pigment
* mucoid
* catheter related blood infections