Naturally occurring xanthine urolithiasis in a domestic shorthair cat

A five-year-old neutered male domestic shorthair cat was presented after three episodes of urethral obstruction and anuria requiring relief urethral catheterisation. A double contrast cystogram revealed the presence of multiple small cystoliths which were radiolucent on plain radiographs. A perineal urethrostomy and a cystotomy were performed to relieve the urethral obstruction and to remove the cystoliths. Quantitative analysis revealed the cystoliths to be composed of 100 per cent xanthine. Clinical history suggested the xanthinuria to be naturally occurring. Unfortunately, the cat was killed in a road traffic accident two months after the surgical procedure, preventing further long-term assessment.