Idiopathic detrusor-urethral dyssynergia in dogs: a retrospective analysis of 22 cases.

Results of a retrospective study of 22 dogs with signs of dysuria and/or stranguria in which a diagnosis of idiopathic detrusor-urethral dyssynergia was made are presented. The diagnosis was based on the exclusion of detectable pathological conditions which could also cause urine outflow obstruction. The affected cases were 22 middle-aged male dogs (mean age 4.9 years) of large and giant breeds (mean bodyweight 36.7 kg). Nine dogs had had periodic clinical signs for longer than one year, one for seven months and eight for two to five weeks, while in four dogs signs had begun four to five days before referral. All dogs received the alpha-sympatholytic agent prazosin as an initial treatment and in 11 it remained the only therapy. There was a good effect in seven and a moderate response in the other four dogs. In one dog, prazosin was ineffective and was replaced by diazepam, which markedly reduced the signs. Three other dogs required frequent catheterisation and antibiotics were administered. These dogs responded favourably. Another three dogs with evidence of impaired bladder contractility were also treated with the parasympathomimetic agent carbachol. One did not improve and was euthanased. Four dogs developed bladder paralysis and severe infectious cystitis. Only one of these could be managed satisfactorily by long-term administration of prazosin, carbachol and antibiotics, and the others had to be euthanased.