My dog has a wound that won't heal. I took her to the vet in January 2011 to have a cyst that has ruptured removed. After the stitches were taken out it healed and two weeks later it the scar swelled up (not the cyst returning) and it split open again. I took her back to the vet, they opened it up again removed more tissue and used a K-laser on it and after two months of the K-laser it seemed to heal but it again blistered up and ruptured again. I took her to another vet were they took some tissue out and within another month split open again. I took her to a third vet the went in the wound and put antibiotic gel in it. All three vets gave me antibiotic pills each time. Now as of 6 November 2011 it has split open again and I don't know what to do. Two of the vets have also done airobic and anairobic bacteria smears and come back negative (after three or four weeks of not taking antibiotic). What can it be? Three Vets were at a loss and I sure don't know what to do. HELP