Focal metatarsal sinus tracts in a Weimaraner successfully managed with ciclosporin

Focal metatarsal sinus tracts (‘fistulation’) are, to the authors knowledge, reported for the first time in a Weimaraner. The six‐year‐old, entire male had a five‐month history of two symmetrical, well‐demarcated sinuses on the plantar aspect of each metatarsus. The area surrounding each pair of sinuses was slightly fluctuant and a serosanguineous discharge could be expressed. Cytological examination of the discharge was characteristic of pyogranulomatous inflammation. Bacterial culture showed the material to be sterile. Examination of a skin biopsy revealed a severe inflammatory reaction involving the dermal collagen, with an infiltrate of neutrophils, macrophages, lymphocytes, plasma cells and multi‐nucleated giant cells, with some micro‐pustule formation. Treatment with ciclosporin induced total remission. Reduction of the dose of ciclosporin resulted in recurrence of the physical signs with further remission on re‐introduction of the original dosage. This is the first report of the use of ciclosporin to control this condition.