Cystine urolithiasis-free duration after first occurrence and treatment is longer for castrated dogs than for sexually intact male dogs.

Objective: To evaluate outcome in 60 dogs with cystine urolithiasis treated with surgical removal with and without castration and postoperative therapeutic diet to determine frequency of recurrence and urolith-free duration.

Methods: Patient records were reviewed for dogs with documented cystine urolithiasis from September 2010 to December 2020. Medical records, client interviews, and referring veterinarians were contacted to document the absence of clinical signs associated with subsequent urolith formation and to evaluate risk factors for urolith reoccurrence.