Microbiology

Question 1

(T/F) You do not generally need to run anaerobic cultures on canine or feline urine specimens because the most common bacteria causing bladder cystitis are obligate aerobes or facultative anaerobes.

Answer 1

(T; list includes the Enterobacteriales (these guys are the most common), Staph pseudintermedius, Beta hemolytic streps and enterococci, and pseudomonas aeruginosa)

Question 2

Leptospira are gram negative/positive (choose one), strict/facultative (choose one) aerobes with a spiral shaped morphology.

Answer 2

(Gram negative, strict aerobes)

Question 3

(T/F) Leptospira cannot grow in typical diagnostic laboratories.

Answer 3

(T)

Question 4

What is the natural reservoir for leptospira?

Answer 4

(The renal tubules of subclinical carriers who will excrete leptospira constantly or intermittently in their urine)

Question 5

Besides exposure to urine of asymptomatic carrier animals, how else can animals be exposed to leptospira? Two answers.

Answer 5

(Directly/indirectly from a contaminated environment and body secretions of a clinical animal (urine, milk, semen, placenta, etc.))

Question 6

Which virulence factor of leptospira causes vascular damage and is a hemolysin (results in hemoglobinuria)?

Answer 6

(Sphingomyelinase)

Question 7

(T/F) Leptospira is a facultative intracellular bacteria.

Answer 7

(F, but they do have the ability to invade cells, that’s how they get from the blood into the renal tubules)

Question 8

In a canine patient, will Leptospira canicola (which is host-adapted for canines) or Leptospira pomona more likely cause significant disease?

Answer 8

(Leptospira pomona since it is not host adapted to canines; Leptospira canicola is more likely to cause an infection but it will also more likely be a subclinical infection whereas as with incidental infections (any other non host-adapted serovar such as pomona), they are more likely to cause clinical disease in animals they are not host-adapted to)

Question 9

What CBC changes often result from leptospirosis in dogs? Four answers.

Answer 9

(Anemia, neutrophilia, lymphopenia, and thrombocytopenia)

Question 10

What is the most common outcome of swine incidental leptospirosis?

Answer 10

(Abortion)

Question 11

What is the most common outcome of equine incidental leptospirosis?

Answer 11

(Equine recurrent uveitis)

Question 12

What are the limitations of PCR diagnostic testing for leptospirosis? Two answers.

Answer 12

(It does not provide information about the serovar and it is only useful in acute infections)

Question 13

What antimicrobial is recommended for treatment of leptospirosis in dogs?

Answer 13

(Doxycycline)