Type Ib (tubular) non-communicating colonic and rectal duplication in a cat

A six-year-old, 4.14-kg, female spayed domestic shorthair
cat was referred for vomiting, obstipation, tenesmus and
stranguria for five days. On abdominal radiographs, a soft
tissue mass effect was visible at the pelvic inlet. During
abdominal ultrasound, a tube-like structure filled with
hyperechogenic fluid was identified dorsal to the urinary
bladder displacing the colon. A presumptive diagnosis
of pyometra was made. Exploratory laparotomy revealed
the presence of a tubular antimesenteric colonic and
rectal mass causing almost complete compression of
the urethra, descending colon and rectum. The mass
was surgically resected. Histology confirmed a colonic
duplication. There was no recurrence of clinical signs
for six months. This report emphasises that colonic
duplication is a possible differential diagnosis for
prepelvic and intrapelvic masses in feline patients.
Surgical excision of the duplication is a viable treatment
option, alleviating clinical signs and offering good long-term
outcome.