Enterobacteriaceae 2 Flashcards
What are the Yersinia spp?
Y. pestis (non motile), Y. enterocolitica (motile), Y. pseudotuberculosis (motile)
What type of bacteria is Yersinia spp?
gram (-) rods, facultative anaerobes, Grow on BA & MAC
On a giemsa stain how to Yersinia spp. appear?
bipolar staining rods
Pathogenesis of Yersinia spp. occurs how?
survival inside macrophages via their outer proteins that inhibit outer proteins inhibition of both phagocytosis and proinflammatory cytokine production.
Which Yersinia species is associated with the Human and Feline plague? (i.e. Bubonic plague and pneumatic plague)
Yersinia pestis
Why is Yersinia pestis more invasive than the other Yersinia spp?
possesses ADDITIONAL VIRULENCE factors including an antiphagocytic protein capsule and a plasminogen activator which aids systemic spread.
What are the hosts for Y. enterocolitica?
-Pigs, other domestic animals, wildlife -Ewes -Humans
Subclinical enteric infections, occasionally enteritis is a consequence of Y. enterocolitica in what species?
Pigs, other domestic animals, wildlife
Sporadic abortion due to Y. enterocolitica occurs in what species?
sheep
Gastroenterocolitis due to Y. eneterocolitica is seen in what species?
humans
Y. pseudotuberculosis is hosted in what species?
-Farmed deer, sheep, goats, cattle, buffaloes, pigs -Cattle, sheep, goats -Guinea pigs, other laboratory animals -Caged birds -Humans
Enteritis in young animals, subclinical infections common in older animals, mesenteric lymphadenitis - is seen in what species and what Y. spp.?
Farmed deer, sheep, goats, cattle, buffaloes, pigs. Y. pseudotuberculosis
In Cattle, sheep, goats, Sporadic abortion is seen as a consequence of infection with what Y. spp?
Y. pseudotuberculosis
With Y. pseudotuberculosis, Focal hepatic necrosis, septicaemia is seen in what species with infection?
Guinea pigs, other laboratory animals
With Y. pseudotuberculosis, what is seen on infection with caged birds?
Septicaemia
Humans infected with Y. pseudotuberculosis present with what?
Enterocolitis, mesenteric lymphadenitis
What Yersinia spp. presents with plague in different species?
Yersinia pestis -Humans = Bubonic and pneumonic plague -Rodents = Sylvatic plague -Cats = Feline plague
What species is most susceptible to Y. pestis?
cats
How is the plague transmitted?
Y. pestis is transmitted by fleas (Xenopsylla cheopis) → Rodents including squirrel.
How do cats transmit the plague to their humans?
Aerosol transmission: cats directly to humans when they cough infectious droplet into the air
What species are less/not susceptible to the plague?
-dogs less susceptible -Cattle, horses, pigs not involved
Are the plague endemic regions in the US?
Yes - Plague endemic in wild rodents in Arizona, California, New Mexico
What does Yersinia pestis clinically present with due to the dissemination of the infection?
Gangrene (“Black death”)
What are the three forms of the plague?
- Bubonic form: enlarged lymph nodes (buboes): Less serious, easier to treat 2. Septicemic form: acute, serious may occur without lymphadenopathy. 3. Pneumonic form: serious may result in haematogenous spread.
How is Y. Pestis diagnosed?
Symptoms, blood/aspirate Giemsa stained smear (bipolar staining rods), culture, serology, PCR
What are the treatment and control methods for Y. pestis?
Antibiotics (e.g. tetracycline). Hospitalize the infected cat. Treat for fleas, Rodent control. No vaccine for cats.
Yersinia enterocolitica is Primarily a human enteric pathogen that causes Cause diarrhea, mesenteric lymphadenitis. What is important in diagnosing this?
differential diagnosis as many things cause diarrhea
What pathogens only cause localized and sporadic disease?
Opportunistic pathogens
What are the opportunistic pathogens of the enterobacteriaceae?
-Edwardsiella tarda -Enterobacter aerogenes -Klebsiella pneumoniae -Morganella morganii sugsp. morganii -Proteus mirabilis and P. vulgaris -Serratia marcescens
With Ewardsiella tarda infection, what clinical conditions are seen?
Diarrhea; wound infections in some animal species (rare)
Enterobacter aerogenes infection clinically presents with
Coliform mastitis in cows and sows
Klebsiella pneumonia clinical conditions include
Coliform mastitis in cows; endometritis in mares; pneumonia in calves and foals; urinary tract infections in dogs
Morganella morganni clinical conditions =
ear and urinary tract infections in dogs and cats (uncommon)
Proteus mirabilis and P. vulgaris clinical conditions:
Urinary tract infections in dogs and horses; associated with otitis externa in dogs
Serratia marcescens clinical conditions:
Bovine mastitis (uncommon); septicaemia in chickens (rare)
What are the three most commonly isolated Proteus species?
P. mirabilis, P. vulgaris, P. rettgerii
Does Proteus spp. grow on MacConkey agar?
Yes
Which opportunistic enterobacteriaceae species are highly motile and show characteristic spreading/swarming growth on Blood Agar?
Proteus spp. (P. mirabilis, P. vulgaris)
Which opportunistic enterobacteriaceae show as non-hemolytic on blood agar and produce urease?
Proteus spp.
Is Proteus spp. lactose fermentor?
non-lactose fermenter
What type of flagella do Proteus spp. have?
Motile with peritrichous flagella
Generally, where to Proteus spp. survive?
Soil, water, intestinal tract of man and animals
How is urease a virulence factor?
It produces ammonia which irritates mucus membrane in the ureters, bladder, and the urethra
What are the two most common diseases caused by Proteus spp.?
-UTI in dogs and horses -otitis externa in dogs and cats *Diarrhea in young mink, lambs, calves, goats and pups is also seen
Why must antibiotic sensitivity tests be performed for Proteus spp.?
Because their sensitivity is NOT predictable, therefore, tests need to be done to ensure effective therapy
Fluroquinolones (enrofloxacin) and Aminoglycosides (gentamicin) are usually effective treatments for an infection with what opportunistic Enterobacteria?
Proteus spp.
Proteus spp. typically have resistances to which two drug types?
Tetracyclines and Beta-lactams (penicillin)
How is Proteus disease controlled?
Predisposing factor should be identified and eliminated.
Which one of the following is NOT associated with Proteus mirabilis 1. Unpredictable antimicrobial drug susceptibility. 2. Septicemia and abortion in cattle. 3. Otitis externa in dogs. 4. Urinary tract infection in dogs. 5. Swarming growth on blood agar.
- Septicemia and abortion in cattle.
What is the most common pathogenic species of Klebsiella?
K. pneumoniae
Which opportunistic pathogen has a thick mucoid capsule that produces visibly abundant growth on Blood Agar and MacConkey agar as Lactose fermenter? (grows mucoid colonies)
Klebsiella
Which opportunistic invader is usually Nosocomical (from a hospital) and often drug resistant?
Klebsiella
What opportunistic pathogen is known to cause Meritis in mares resulting in temporary infertility?
Klebsiella
What pathology in cattle is typically the result of contaminated wood shaving with Klebsiella?
Coliform mastitis
What condition is seen as a result of Klebsiella in dogs?
Dogs: urinary tract infections, otitis externa.
In companion birds, what is seen as a result of Klebsiella?
Companion birds: respiratory infections, septicemia, diarrhea.
T/F Klebsiella is similar to E. coli in that they have a variety of host types BUT they are not considered a cause of diarrhea in dogs, cats, or farm animals/poultry
TRUE
T/F Because Klebsiella pneumoniae is typically drug resistant it is not necessary to perform antibiotic sensitivity tests
FALSE
K. pneumoniae Infection in companion birds is treated with:
Enrofloxacin
K. pneumoniae infection in dogs is treated with:
Gentamicin
Which opportunistic enterobacteriaceae have an available LPS core vaccine for mastitis?
Klebsiella
In stressful situations or concurrent disease, what two species of Klebsiella can cause respiratory infections, septicemia, and diarrhea?
K. pneumoniae and K. oxytoca
Gentamicin and Amikacin are useful drugs for genital infections in horse caused by which opportunistic pathogen?
Klebsiella
What are the species of Shigella?
S. dysenteriae, S. flexneri, S. boydii, S. sonnei
What is different with Shigella than other enterobacteriaceae discussed?
Non–motile; Non–ferment lactose (NLF) with exception of S. sonnei
Which enterobacteriaceae cause classical bacillary dysentery in humans and monkeys?
Shigella
Which enterobacteriaceae invade mucosal cells of the intestine, causing cell death and sloughing off into the gut lumen?
Shigella
Which species are resistant to the development of Shigella?
Dogs and food producing animals (cattle)
What are the four Shigella species that produce the classical cytotoxin (shiga toxin)?
S. dysenteriae, S. flexneri, S. boydii, S. sonnei
T/F Shigellosis in horses is caused by an Actinobacillus equi infection
TRUE
Which one of the following statements is FALSE with regard to Shigella 1. It causes dysentery in humans. 2. It produces Shiga toxin. 3. Beef cattle are common carriers. 4. Dogs are resistant to clinical disease. 5.”Shigellosis” in horses is not due to Shigella
5.”Shigellosis” in horses is not due to Shigella
