Campylobacter and Helicobacter

Characteristics of Campylobacter

• Microaerophilic

  • reduced O2

• oxidase positive

• curved gram negative bacilli

What motility type is seen in Campylobacter?

• “darting” motility

  • via polar flagellum

How is Campylobacter obtained?

• poultry

• unpasteurized dairy

• surface water

• contact with: dogs,cats,birds, cattle, sheep, and swine

  • zoonotic

What are the most common species of Campylobacter

• C. jejuni subspecies: jejuni

• C. jejuni subspecies: doylei

What is the pathogenesis of Campylobacter?

• invades the mucosa

What virulence mechanisms are seen in Campylobacter?

• cholera-like enterotoxin

  • causes watery diarrhea

• cytotoxin

  • causes bloody diarrhea

• motility

• LPS endotoxin

What condition is Campylobacter associated with?

• Gullain-Barre syndrome

What is Guillain-Barre syndrome?

• autoimmune neurological disorder

• antibodies bind to gangliosides on peripheral nerves

What are examples of Enteric Campylobacter?

• C. coli

• C. lari

• C. upsaliensis

Characteristics of C. fetus.

• spread via zoonosis

  • cattle

• rare in humans

What does C. fetus cause?

• Bacteremia

  • in immunocompromised/suppressed individuals and geriatric individuals

What lab sample is needed for Campylobacter diagnosis?

• stool or blood specimen

• 3-day rule for hospital with stool culture ordered

  • if longer than 3 days, cancel test

What tests can be run for Campylobacter diagnosis?

• Cary-Blair Transport medium : stool

• Blood culture bottles : blood

What media can be used to identify C. jejuni, C. coli, C. upsaliensis, and C. lari

• Campy-blood agar

• Campy CVA

• Skirrows media

• Charocoal-cefoperazone deoxycholate agar

What incubation methods are necessary for Campylobacter?

• Microaerophilic jars or bags

  • environment that contains lower levels of dioxide

• examine at 48 and 72 hours

What temperature is needed for a stool sample that might have Campylobacter?

• 42 C

What characteristics would lead to the identification of Campylobacter?

• growth on selective media at 42 C

• gram stain morphology (curved bacilli)

• Oxidase +

• Catalase +

• darting motility

What type of Campylobacter is the only one that engages in hippurate hydrolysis?

• C. jejuni

Helicobacter Characteristics.

• found in gastric and enterohepatic tracts of humans

• found in groundwater

What type of Helicobacter is found in gastric tissue of humans?

• H. pylori

What does H. pylori cause?

• Gastritis (type B)

• Ulcers

• Gastric carcinoma

What virulence mechanisms are associated with H. pylori

• Motility

• Attachment

• Survival in acidic environment

• Catalase +

What mechanisms allow H. pylori to survive in an acidic environment?

• associated with mucus and mucus secreting cells

• Urease +

  • releases CO2 and ammonia

Survival of H. pylori depends on what

• urease production

  • Urease +

What indicators would cause a physician to what to test for H. pylori

• dyspepsie

• hematemesis

• weight loss

• anemia

What test can help identify H. pylori?

• Gastric Biopsy

What culture is not acceptable for H. pylori

• fecal sample

What selective media can be used to ID H. pylori?

• Skirrows Media

• Brucella agar with antimicrobials

What conditions should culture media of H. pylori be kept at?

• Microaerophilic

• 35 C

What culture characteristics would point to H. pylori?

• Oxidase +

• catalase +

• rapid urease test +

What nonculture diagnostic methods can be used to identify H. pylori?

• Histologic stains

• direct antigen detection

  • feces and gastric biopsy

• Urea breath test

• rapid urease test

How is H. pylori treated?

• triple therapy of PPI and antimicrobial agents

• 10-14 days for eradication

  • urea breath or fecal antigen test confirm eradication 3-4 weeks after completing treatment