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SUMMER 2016 ISSUE
EQUINE MATTERS
6
CASE STUDY
infection
(figure 4)
. A swab was submitted for
bacterial culture and sensitivity to ensure the
correct antimicrobials could be used.
Bracken was discharged from the hospital on
oral potentiated sulphonamides, and healing
started well.
E. coli and Staphylococcus
aureus were grown and both were reported
to be sensitive to the chosen antimicrobial.
Interestingly, this swab confirmed one of
the bacteria identified was resistant to the
antimicrobial that was being given prior
to surgery.
A routine check up ten days after surgery
revealed an increase in discharge and
swelling, although the wound was healing
well
(figure 5)
. A second swab was taken to
ensure new bacteria had not started to grow.
This result agreed with the previous sample,
leading to discussion as to why the wound
was starting to deteriorate again. Potentiated
sulphonamides are the commonest prescribed
antibiotic in equine practice as it can be
given as granules in feed, and has a broad
spectrum of activity, meaning that most
common bacteria are susceptible to it.
However, this antibiotic is deactivated in the
presence of pus, as in this case, rendering it
less useful in discharging wounds. In light of
this, we discussed the options with the owner
and we agreed to start Bracken on a short
course of intravenous gentamicin. The wound
immediately dried up
(figure 6)
and healed
within a couple of weeks.
With the threat of antimicrobial resistance
becoming more widespread in human and
animal populations, it is critical to make
every effort to ensure these drugs are only
prescribed when absolutely necessary, at the
right time in a case, for the right duration, by
an appropriate route and at the right dose.
Patient compliance can be a significant issue,
with horses often not eating medication, and
the limited choice of oral drug available to
equine vets does little to help! It is important
that we are protective of these drugs or a
future without antibiotics will be our reality.
Figure 3. The difference between normal and abnormal tissue is clear
Figure 6. Clean, healthy granulation tissue, the hallmark of good
wound healing
Figure 5. Discharge on the healing wound
Figure 4. The unhealthy tissue has been removed.