18. Campylobacter genus and helicobacter pylori

Question 1

Characteristic of both the bacterias!
Shape,
Stain
Special appandage..
Preferntial enviroment!

Answer 1

SPIRAL, CURVED
GRAM NEGATIVE RODS
Microaerophil (5-7% O2, 5-10% CO2)
Flagellated

Question 2

Biochemical characteristic of both! (2 examp)

Answer 2

Catalase +, oxidase +

Question 3

What special char does Helicobacter pylori have!

Answer 3

urease!

Question 4

What special char does Campylobacter have

Answer 4

Termophil.

Question 5

Campylobacter jejuni, coli.

Natural apperance!

Answer 5

Domestic and wild animals are the reservoirs for the organisms (birds intestine, cow – milk).

Question 6

Morphology of camylobacter jejuni

Answer 6

Morphology: - comma-shape rod, single polar flagella, motile

Question 7

camylobacter jejuni
Source of infection!
3 sources.

Answer 7

Source:
1. not properly cooked meat (zoonosis!)
very low dose: 10^2 bacteria enough!
2. unpasteurised milk
3. human-to-human: fecal-oral (rarely)

Question 8

camylobacter jejuni incubation time+ Symptoms (3 of them).

Answer 8

Incubation time: 1-2 days
Symptoms:
bloody, mucous feces
fever
strong abdominal pain

Question 9

camylobacter jejuni rare outcomes!

Answer 9

Outcome:
spontaneous recovery
complications: 
systemic infection
Guillain-Barré syndrome( an acute neurological disease, the Guillain-Barré syndrome)

Question 10

camylobacter jejuni
Diagnosis!
Clinical specimen from!?
Specimen?!

Answer 10

Clinical specimen: faeces, blood for blood culture.
Direct smear: Gram stained direct smear of diarrhoeal faeces may show “gull wing or “comma”shaped Gram negative bacilli.
Faeces may also contain RBCs and granulocytes. Dark-field or phase contrast microscopy can show the typical darting motility.

Question 11

camylobacter jejuni

Culture (3 examples!)

Answer 11

Culture:

1) On different selective media ( Skirrow’s – contains antimicrobials )
2) At 40~ Celius! / it prohibits growth of most of the other bacteria in feces.
3) - in microaerophilic conditions (5 % O2, 10% CO2) → Colonies are colourless or grey, may be watery or spreading, round-shaped and convex.

Question 12

camylobacter jejuni biochemistry diagnostics

Answer 12

oxidase +, catalase +

Question 13

camylobacter jejuni treatement.

3 examples!

Answer 13

Treatment:
1) Supportive therapy- fluid & electrolite replacement
2) Drugs: - Erythromycin, Ciprofloxacin.
If systemic infection use a more powerful drug… (carbapenem, aminoglycoside,)
3) Food hygine! Avoid undercooked or under-fried poultry.

Question 14

Campylobacter fetus C. fetus…

Answer 14

S-protein ⇒inhibition of binding of C3b⇒ antiphagocytic effect Opportunistic pathogen - systemic infection (endocarditis, meningitis) - rarely enteritis Treatment: - gentamicin, Chloramphenicol, Ceftriaxon

Question 15

Morphology of Helicobacter pylori!
3 important things!
Also remember 2 important biochem shared with both bacteria and…
Favorable area to grow.

Answer 15

Morphology: - spiral – shaped rod,
multiple flagella at one pole,
motile

Question 16

Special helicobacter phylori chemical rxn!!!

Answer 16

urease+!!!!

Question 17

Pathogenesis:

helicobacter phylori

Answer 17

Pathogenesis:

• H. pylori is motile / multiple flagella at one pole / and is able to find its way to the epithelial surface, where physiologic pH is present - they live just under the gastric mucus on the epithelial side → relatively impermeable to acid and has a good buffering capacity .
• produce:
  1) urease → ammonia production → further buffering of acid.
  2) protease → modifies the gastric mucus → further reduction of the ability of acid to diffuse through the mucus.

After ingestion → development of gastritis and hypochlorhydric.
Toxins and LPS → damage to the mucosal cells and ammonia production → dyspepsia, peptic ulcer stomach cancer develops.

Question 18

helicobacter phylori
Diagnostic Laboratory Tests:
Clinical specimen!
Direct smear!

Answer 18

Clinical specimen: gastric biopsy, blood for serology.

Direct smear: gastric biopsy specimen stained by Giemsa, or silver impregnation may show typical curved or spiral bacteria

Question 19

helicobacter phylori Culture

Answer 19

• on different selective media / Skirrow’s / - in microaerophilic conditions (5 % O2, 10 % CO2) → Colonies are colourless or grey, may be watery or spreading, round-shaped and convex.

Question 20

Biochemical rxns for diagnostics of helicobacter pylori (3 of them!))

Answer 20

Urease+ Oxi+ cat+

Question 21

Serology of Helicobacter!

Answer 21

Blood serology: specific IgG antibodies in the patients` sera. A positive result is not diagnostic for acute infection, after eradication therapy it is still positive, but a negative test excludes H. pylori infection.
Use Western blot for conformation!

Question 22

Special test for helicobacter!

2 of them

Answer 22

1) - gastric biopsy material can be placed onto a urea-containing medium with a colour indicator ⇒ if H. pylori is present, the urease rapidly splits the urea and the resulting shift in pH yields is colour change in the medium.
2) - 14C-urea breathing test: after labelled urea is ingested ⇒ if H. pylori is present the labelled CO2 can be detected in the patient’s exhaled breath.

Question 23

Therapy for helicobacter pylori!

Answer 23

Combined 2-week therapy

1) Proton-pump inhibitors (PPI)
2) Antibiotics
Clarithromycin + metronidazole
Amoxicillin + metronidazole
Doxycycline + metronidazole
3) Bismuth salts