Stump pyometra in a spayed female dog secondary to tamoxifen

Abstract

Objective To describe a complication associated with the long‐term use of tamoxifen for the treatment of sclerosing encapsulating peritonitis in a dog. Case Summary A 2‐year‐old female spayed poodle cross was evaluated for a stump pyometra. The dog was diagnosed with sclerosing encapsulating peritonitis a year prior and was treated with tamoxifen, an oestrogen receptor antagonist, for treatment of the disease. The dog developed a swollen vulva with vulvar discharge and a stump pyometra was diagnosed on ultrasound. Hormonal testing was submitted to evaluate for an ovarian remnant and the dog underwent an exploratory laparotomy, where the uterine stump was removed. No ovarian remnant tissue was identified intra‐operatively, and hormonal testing (anti‐Müllerian hormone, progesterone, oestradiol) and histopathology were consistent with the absence of ovarian tissue. The tamoxifen was discontinued. The dog recovered uneventfully after surgery. New or Unique Information Provided This report describes a complication of treatment of a rarely described clinical disease. While most cases of stump pyometra involve ovarian remnant syndrome, this case report describes a stump pyometra in a dog without remnant tissue that was undergoing treatment with tamoxifen. Tamoxifen has been reported to cause pyometra in intact female dogs. To the authors’ knowledge, this is the first case report to describe a stump pyometra in a spayed female dog, secondary to the use of tamoxifen.

Canine Pyometra: A Short Review of Current Advances

“…Complications associated with OHE include hemorrhage, accidental ureteral ligation, estrogen-responsive urinary incontinence, ovarian remnant syndrome, and stump pyometra [69,70]. Stump pyometra may develop post-OHE if a section of the uterine horns or body remains and the animal exhibits elevated progesterone levels and/or an ovarian remnant [69][70][71]. The clinical manifestation, diagnosis, and treatment of stump pyometra are similar to those for pyometra, except for the history of a prior OHE [23].…”

WSAVA guidelines for the control of reproduction in dogs and cats

“…In countries where gonadectomy is only allowed for therapeutic reasons, incidence varies between >20 and 54% in female dogs up to 10 years old depending on age, breed and geographic location (Arendt et al, 2021;Egenvall et al, 2001;Hagman, 2018;Hart et al, 2014;Jitpean et al, 2012;Reichler, 2009;Urfer & Kaeberlein, 2019). Exogenous oestrogen and progesterone administration or its endogenous secretion (in case of ovarian remnant) may cause uterine disease in ovariectomised female dogs or ovariohysterectomised female dogs with a uterine remnant (Ball et al, 2010;Ehrhardt et al, 2023;Parker & Snead, 2014;Sterman et al, 2019). Complete removal of the uterine tissue including the cervix prevents pregnancies and prevents or cures uterine diseases.…”

Piometra De Coto Com Aderêncial Total a Vesícula Urinária: Relato De Caso

“…Em outras palavras, Musal e Tuna (2005), dizem que a piometra de coto uterino é uma complicação decorrente de uma inflamação e infecção bacteriana do corpo uterino remanescente. Frisam também que alguns fatores podem influenciar a ocorrência desse processo infecioso, por exemplo, resíduo de tecido ovariano, secreção de progesterona, ciclos ovarianos, inflamações e infecções ou secundários à medicamentos (Ehrhardt et al, 2023).…”