Urinary Bladder Anomalies in Animals

Congenital anomalies resulting from urachal remnants or incomplete urachal closure include patent urachus (failure of the urachus to occlude at the umbilicus), urachal diverticulum, umbilical urachal sinus, and intra-abdominal urachal cyst.

These conditions can be present in any domestic species but are most frequently a clinical problem in cats, dogs, and horses.

Clinical signs depend on the type of anomaly. Patent urachus is typically associated with continuous urinary incontinence, urine scalding of the ventral abdomen, and development of secondary bacterial urinary tract infections (1).

Patent urachus, foal

Image

Courtesy of Dr. Sameeh M. Abutarbush.

Urachal diverticula also predispose to urinary tract infection by serving as a nidus for bacteria.

Definitive diagnosis of both disorders is by positive contrast cystography.

Treatment consists of surgical resection and 2–4 weeks of appropriate antimicrobial treatment, when indicated. Surgical resection is the standard treatment for umbilical urachal sinuses and intra-abdominal urachal cysts.

Urinary bladder duplication, dysplasia, hypoplasia, agenesis, and exstrophy (congenital eversion of the bladder outside the abdominal wall) have been reported and are often associated with other urinary tract defects.

Clinical signs depend on the type of anomaly.

Diagnosis is by physical examination, observation of micturition, and contrast radiography.

Treatment depends on the type of anomaly.

1. Reig Codina L, Werre SR, Brown JA. Short-term outcome and risk factors for post-operative complications following umbilical resection in 82 foals (2004-2016). Equine Vet J. 2019;51(3):323-328. doi:10.1111/evj.13021