Pharm II Final

Question 1

Name 6 oral antimicrobials with good oral absorption in horses.

Answer 1

1. Trimethoprim Sulfa (TMS)
2. Metronidazole
3. Enrofloxacin
4. Erythromycin
5. Rifampin
6. Chloramphenicol

Question 2

Name three antimicrobials commonly used IM in horses.

Answer 2

1. Ceftiofur
2. Procaine Pen G
3. Aminoglycosides

Question 3

Name three drugs that should NEVER be used IM in horses

Answer 3

1. Erythromycin
2. Tetracyclines
3. Enrofloxacin

Question 4

Name two drugs that are more likely to cause enterocolitis in horses due to enterohepatic circulation

Answer 4

Tetracyclines and erythromycin

Question 5

Name two factors associated with an antibiotic that might make it more likely to cause enterocolitis in horses

Answer 5

Oral is riskier than parenteral

Broad spectrum is riskier than narrow spectrum

Question 6

Name two types of bacteria prone to overgrowth in antimicrobial associated enterocolitis in horses

Answer 6

Clostridium spp

Salmonella spp

Question 7

When would you expect to see antimicrobial associtated enterocolitis develop in horses?

Answer 7

Within 7 days of drug administration

Question 8

What are some clinical signs of enterocolitis in horses?

Answer 8

Dehydrating diarrhea and endotoxemia
Neutropenia and hypoproteinemia
Electrolyte and acid-base imbalances

Question 9

What is the diagnosis of enterocolitis in horses based on?

Answer 9

Presumptive (they’ve been on abx) and fecal cultures for salmonella and clostridium (or toxin assays)

Question 10

Name three classes of drugs you should avoid in adult horses

Answer 10

1. Macrolides (like erythromycin)
2. Lincosamindes (like Lincomycin and Clindamycin)
3. Oral beta-lactams

Question 11

True or false, almost ever all antimicrobial has been associated with enterocolitis in horses and you should always warn your clients?

Answer 11

True true true

Question 12

For a “clean” surgery, in a horse, what prophylactic drug protocol would you want to use?

Answer 12

IV or IM penicillin, only before surgery (1 hr prior if IV, or 3 hr prior if IM)

Question 13

For a “contaminated” surgery, what prophylactic drug protocol would you want to use in a horse?

Answer 13

IV penicillin and gentamicin

Start 1 hr prior to surgery and continue until 24 hrs after surgery

Question 14

For a “dirty” surgery in a horse, what prophylactic drug protocol would you want to use?

Answer 14

IV penicillin and gentamicin

Start 1hr prior to surgery and continue until 72hrs post surgery

Question 15

What broad categories of structures can be affected in septic synovial problems?

Answer 15

Bursts, joints, and tendon sheaths

Question 16

If you pull fluid from a suspected septic synovial structure, what WBC count would confirm you suspicion?

Answer 16

WBC>30,000 (mostly neutrophils)

Question 17

What would the TP be in a septic synovial structure?

Answer 17

TP=3.5-4.0 gm/dl

Question 18

What is the gold standard for testing for synovial sepsis?

Answer 18

Culturing the synovial membrane

Question 19

What should you think if you suspect synovial sepsis in a horse, but you get a negative bacterial culture?

Answer 19

bacteria were seen in only 24% of cases. A negative culture result could bean sequestration of bacteria within the synovial membrane, neutrophils, or fibrin.

Question 20

Which bacteria is likely to cause iatrogenic septic arthritis in horses?

Answer 20

Staph. Aureus

Question 21

Which bacteria are likely to cause hematogenous septic arthritis?

Answer 21

E. Coli, Klebsiella, Actinobacillosis, strep. Salmonella, rhodococcus equi

Question 22

Which bacteria are likely to cause traumatic septic arthritis, tenosynovitis, or bursitis in horses

Answer 22

Strep, staph, Enterobacter, Pseudomonas, and anaerobes

Question 23

Which bacteria are likely to cause osteomyelitis in horses?

Answer 23

Enterobacter, Strep, Staph, and Pseudomonas

Question 24

What is the treatment for septic synovial structure?

Answer 24

Wound debridement +/- closure

Question 25

When dealing with septic synovial structures, what is it that causes pain? What is the solution to this?

Answer 25

Distention causes pain, and synovial lavage can help relieve that distention.

Question 26

How much fluid should you use, and how often should you perform synovial lavage in horses?

Answer 26

1-2 liters of sterile fluid every day or every other day

Question 27

What might be present that could cause synovial lavage to be ineffective?

Answer 27

Large amounts of fibrin

Question 28

What antimicrobial protocol should you use for septic synovitis?

Answer 28

Broad spectrum until C&S are known
IV for 5-7 days then switch to oral and continue for 2 wks following resolution of signs.

Use Aminoglycosides + Penicillin OR cephalosporins
(Avoid TMS due to too much resistance)
** Can also use local aminoglycosides, Flouroquinolones, or metronidazole

Question 29

Name three bacteria that can be related to peritonitis in horses

Answer 29

Streptococcus
Corynebacterium
Rhodococcus

Question 30

What is the treatment for peritonitis due to an abdominal abscess?

Answer 30

Long term antimicrobial to, +/- surgery

Question 31

How do you know when you can cease tx for peritonitis due to an abdominal abscess?

Answer 31

WBC count, serum fibrin Conc, ultrasound, etc will all show resolution

Question 32

What classes of drugs should be used to tx diffuse peritonitis in horses?

Answer 32

beta lactams + aminoglycosides + metronidazole

Question 33

Name two antibiotics with good oral absorption that can be used in foals but shouldn’t be used in adult horses

Answer 33

Erythromycin and Rifampin