Calcinosis circumscripta following an injection of proligestone in a Burmese cat

A 9-month-old speyed Burmese cat was presented with a cutaneous lesion in t he dorsal thoracolumbar region. The lesion was characterised by alopecia an d whitish deposits within the subcutis and had occurred at the site of a pr evious progestogen injection (CoVinan; Intervet). Excisional biopsy confirm ed the diagnosis of calcinosis circumscripta. Recovery of the cat following surgical excision was excellent, with no recurrence of the lesion detected 12 months later. The classification of tissue calcification and the propos ed aetiology of calcinosis circumscripta is reviewed. It is concluded that further work is required to determine any link between subcutaneous injections, especially of progestogens, and calcinosis circum scripta.