Canine Pyoderma - Online Veterinary Cpd From The Webinar Vet

In this article and as part of your ongoing veterinary cpd we are going to be discussing Canine Pyoderma. The bacteria most commonly implicated in canine pyoderma isStaphylococcus pseudintermedius. This name change from Staphylococcus intermedius is after a re �classification of the group It is usually resistant to oxytetracycline, penicillin, ampicillin and amoxicillin. These antibiotics should not be used in treating canine pyoderma. An ideal antibiotic should inhibit the specific bacteria in a bactericidal way, although, bacteriostatic antibiotics can be used if the dog is not immunocomprimised. It should have a narrow spectrum so that it does not damage the natural flora of the skin and intestinal tract.

First line antibiotics should be used in straightforward first time cases. These antibiotics include clindamycin and potentiated sulphonamide. Recurrent use of these drugs can lead to drug resistance and, in the case, of potentiated sulphonamides, an increased risk of drug eruption. Also potentiated sulphonamides are known to reduce the thyroid levels and may cause an erroneous diagnosis of hypothyroidism to be made by the unsuspecting clinician

Second level antibiotics include the first generation cephalosporins and potentiated amoxicillin. These can be used when there has been recurrent infections and success of other antibiotics is questionable. They are the favourite of the consultant dermatologist.

Finally third generation antibiotics should be reserved for difficult and unusual cases. These include the third generation cephalosporins such as cefovecin and fluoroquinolones. Cefovecin is a long-acting injectable antibiotic which gives 14 days of activity and should only be used where compliance is a real issue. Its activity is not superior to first generation cephalosporins such as cephalexin and it also has an activity against a range of gram negative organisms. Its use could lead to the development of resistance. Fluoroquinolones appear to select for methicillin resistance and should only be used in cases of deep infection associated with gram negative organisms or where there is already a resistance to cephalosporins.

It is very important to weigh a dog suffering from pyoderma so that an accurate dose of antibiotic is given. As discussed previously, this must be given for a minimum of 3 weeks and much longer in the case of a dog with a deep pyoderma. In my referral clinic I often see histories where the dog has been given seven to ten days of antibiotics and then no more until a month later when the dog returns with its problem. This can happen several times. This on-off use of antibiotics can lead to the development of resistant bacteria such as methicillin resistant staphylococcus aureus(MRSA) or pseudintermedius(MRSP).

In cases where the response to a previously suitable antibiotic is poor, culture and sensitivity should be performed to look for the presence of MRSA or MRSP. Treatment should be based on the results of culture and sensitivity.

More information about this topic can be found at the veterinary webinar Why the dog is a pyoderma waiting to happen.