Unusual fermenters (HACEK and Bioterrorism)

Aggregatibacter aphrohilus disease

Small GNCB

Endocarditis, bone, and joint infections

Dental plaque and gingival scrapings

Aggregatibacter actinomycetemocomitans

periodontisis

small GNCB

Cardiobacterium hominis

normal flora → nose, mouth, throat, GI tract

pitting morphology

fastidious GNR

Oxidase +

Catalase =

Indole +

nonmotile

Eikenella corrodens

normal flora: oral and GI

human bite wounds, IV drug use (licking needle)

Peridontitis, meningitis, pneumonia, osteomyelitis, arthritis, post-op infections

Fastidious, GNCB

corrdoe “pit” agar, bleach-like odor

Kingella kingae

Pediatric infections (bone and joints) → osteoarthritis

resist decolorization

GNCB, squared ends

Oxidase +

Catalase =

nonmotile

May grow on MTM like Neisseria

Capnocytophaga

Normal flora: oral (humans and animals)

Septicemia: dog/cat bites

Thin, fusiform (pointed ends) GNRs

Yellow-orange colonies that adhere to agar

Pasteurella

Zoonotic infection

Dog/cat bites

Systemic: septicemia, arthritis, endocarditis, osteomyelitis, meningitis

GNCB, bipolar staining

Catalase +

Oxidase +

Francisella tularensis

TINY GNCB

Zoonotic

Bioterrorism

Tularemia/Rabbit fever → human accidental host → typhoidal

Bunny or tick

BSL3

Oxidase positive

Catalase weakly positive

Beta-lactamase positive

Send to reference lab

Brucella

Small GNCB

Requires CO2

resists counter stain

Normal flora: farm animals → Zoonotic disease

B. abortus → cattle

B. melitensis → goats/sheep

B. suis (pigs)

B. canis (dogs)

B. neotomae (desert wood rat)

B. ovis (sheep)

Brucellosis, Undulant fever, Malta Fever

Contaminated milk, cheese

• inhalation

• penetration of mucosa

• direct inoculation

Dairy farmers, veterinarians, lab personnel

Brucella agar → BSL 3

Bioterrorism

Oxidase, urease, catalase positive