Lawsonia/Heliobacter Flashcards
What are the Characteristics of Lawsonia and Helicobacter?
- Gram Negative
- Helical Shaped rods
- Obligate intracellular pathogen
- Grows only in tissue culture medium
- Causes Proliferative enteritis in swine
- Proliferation of enterocytes
- 4 forms: Chronic proliferative enteritis, Necrotic enteritis, Regional ileitis, and Acute hemorrhagic enteritis
What is Swine Proliferative Enteritis?
- Other names:
- Regional ileitis
- Porcine Proliferative Enteropathy
- Porcine Proliferative Ileitis
- Also in Horses and Deer
- Occurs worldwide
- Economically important disease
- Generally in weaned pigs (6-20 wk)
- Complex disease: 4 forms
- Common lesion- Thickening of the mucosa
What are the characteristics of Swine Proliferative Enteritis?
- Proliferation of enterocytes
- Hyperplastic to adenoma-like lesions of the terminal ileum, cecum, and colon
- Disease can be reproduced in conventional swine, but not in gnotobiotic swine
- Synergy with intestinal bacteria
What is the habitat of Lawsonia intracellularis?
- Intestinal tracts of pigs and excreted in feces
- also of rodents
What is the mode of infection of Lawsonia intracellularis?
- Ingestion
What are the virulence factors of Lawsonia intracellularis?
- LPS and Surface antigen A (Lsa A)
- Adhesion
What are the 4 forms of Swine Proliferative Enteritis?
- Chronic Proliferative Enteropathy:
- Thickening of the mucosa due to hyperplasia
- Necrotic Enteritis:
- Chronic form with necrotic mucosa
- Regional Ileitis:
- Chronic form with thickening of the muscle (Garden hose gut)
- Acute Hemorrhagic Enteropathy:
- Hemorrhage into the lumen (Black tarry feces)
What are the Clinical Signs of Acute Swine Proliferative Enteritis?
- Most common in young adults of 4 - 12 months of age
- Diarrhea with brownish to black unclotted blood
- Pallor
- Weakness
- Death
What are the Clinical Signs of Subacute/Chronic cases of Swine Proliferative Enteritis?
- Most common in grower pigs
- Sporadic diarrhea
- reduced weight gain and growth rate
What is the Pathology of Swine Proliferative Enteritis?
- Lesions:
- Thickening of the ileum, occasionaly of the cecum and colon
- ‘Cerebriform’ appearance
- Hyperplasia of enterocytes within the crypts of jejunum, ileum, cecum, and colon
- Intracellular bacteria in the enterocytes
- Thickening of the ileum, occasionaly of the cecum and colon
How is Swine Proliferative Enteritis Diagnosed?
- Demonstration of typical lesions
- Demonstration of intracellular organisms in mucosal smears
- Demonstration of organisms in the feces by PCR
What is the Treament for Swine Proliferative Enteritis?
- Whole herd medication with feed additives
- Tiamulin (150 ppm)
- Chlortetracycline (400 ppm)
- Tylosin (100 ppm)
- Vaccine: An avirulent, like vaccine
What is Equine Proliferative Enteropathy?
- An emerging disease that affects mainly foals of 2 - 8 mo
- Seasonal: August to January
What are the clinical signs of Equine Proliferative Enteropthy?
- Fever
- Diarrhea
- Colic
- Ventral edema (Jaw, leg, or abdomen)
- Because of hypoproteinemia
How is Equine Proliferative Enteropathy Diagnosed?
- Abdominal ultasongraphy to visualize thickened intestine
- PCR detection of the organism in feces
- Hypoproteinemia (decreased absorption of protein)
- Lesions:
- Thickened mucosa of the ileum, near ileo-cecal junction
What is the Treatment for Equine Proliferative Enteropathy?
- Macrolides with Rifampin, Chloramphenicol, Oxytetracycline, or Doxycycline administered for 3 weeks
- Swine Vaccine has been used in horses
What are the characteristics of Helicobacter?
- Gram negative
- Helical shaped rods
- Microaerophilic
- Initially 2 species recognized:
- H. pylori: humans
- H. mustelae: ferrets
- Now as many as 45 species
- Have Multiple Polar Flagella
What are the 2 groups of Helicobacter?
- Gastric:
- Produce urease
- H. pylori, H. heilmannii, H. mustelae, H. felis, H. suis
- Enterohepatic:
- Most do not produce urease
- Colonize small intestine and liver
- H. canis, H. hepaticus, H. bilis
What is the habitat of Helicobacter?
- Stomach of humans, primates and animals
- Intestinal tracts of animals
What is the habitat of Helicobacter pylori?
- Stomach of humans, primates, dogs, and cats
What disease does H. pylori cause?
- Chronic gastritis
- Gastric and Duodenal ulcers (peptic ulcers)
What are the clinical manifestations of H. pylori?
- Infection lasts weeks to months - Chronic Gastritis
- Infection lasts years:
- Gastric lymphoma
- Peptic Ulcers
- Gastric Adenocarcinoma
What are the virulence factors of H. pylori?
- Maintnance factors:
- Urease
- Motility
- Mucinase
- Pathogenic factors:
- Adhesins: BapA and HpaA
- Vacuolating cytotoxin: VacA
- Neutrophil activating protein (NAP)
What is the pathogenesis of H. pylori?
- H. pylori infect Gastric lumen
- Mucinase dissolves mucus
- Travels through mucus layer
- Binds to receptor on Gastric epithelial cells
- Release Urease b
- ?reaks down urea
How is H. pylori diagnosed?
- Gastric Biopsy
- Microscopic examination for bacteria, inflammation
- Urease test
- Urea breath test
How does H. pylori affect cats?
- Feline Isolates have been shown to be genetically similar (99.7%) to human islates
- Zoonotic or reverse zoonosis?
What are the Gastric Helicobacter?
-
Helicobacter heilmannii - Stomach of dogs and cats
- Gastritis in dogs, cats, monkeys, ad humans
-
Helicobacter felis - Stomach of dogs and cats
- Gastritis in dogs and cats
-
Helicobacter mustelae - Stomach of ferrets
- Gastritis and ulcers in adult ferrets
-
Helicobacter bizzozeronii - Cat and Dog
- Gastritis
-
Helicobacter suis - Pig, mandrill monkey, rhesus macaque
- Gastritis in pigs
What are the Enterohepatic Helicobacter?
- Helicobacter bilis - Mice, rats, dogs, cats, sheep
-
Helicobacter canis - Found in the feces of dogs
- Multifocal necrotic hepatitis in dogs
- Helicobacter aurati - Hamster
- Helicobacter hepaticus - Mice, Gerbils
- Helicobacter pullorum - Poultry
- Helicobacter equorum - Horse
What is Helicobacter gastritis in Dogs and Cats?
- Persistent intermittent vomiting, sometimes with bile
- Diagnosis: Gastric biopsy
- Urease test
- Spiral organisms
- Inflammatory changes
How is Helicobacter Treated in Cats and Dogs?
- Antibiotics:
- Tetracyclines
- Amoxicillin
- Metronidazole
What are Gastric Ulcers in Pigs?
- Lesions:
- Ranging from parakeratosis to ulcers; Confined to the region around the opening of the esophagus
- Detected at slaughter
- Clinical Sign: Anemia
- Etiology:
- H. suis
- Often in association with Fusobacterium gastrosuis
