Retrospective evaluation of clinical, laboratory, and outcome findings in 42 cases of canine pyometra

Abstract

Pyometra is a severe and potentially life-threatening uterine disorder in intact female dogs, characterized by bacterial infection associated with prolonged progesterone exposure. This study aimed to perform a retrospective evaluation of the clinical, laboratory, and outcome findings of 42 bitches diagnosed with pyometra and submitted to ovariohysterectomy between July 2023 and October 2025. Epidemiological data, hematological and biochemical parameters, as well as clinical signs and postoperative evolution, were analyzed, comparing the open and closed forms of the disease. Open pyometra was more prevalent (69%), while the closed form accounted for 31% of the cases. Most of the affected dogs were adults or elderly, with ages ranging from 1 to 18 years, and the most frequently affected breeds were mixed-breed (40.5%) and Poodle (11.9%). Laboratory findings revealed normocytic normochromic anemia and leukocytosis due to neutrophilia with a left shift. The most common biochemical alterations included increased urea and creatinine concentrations, along with hyperproteinemia and mild elevation of alkaline phosphatase, indicating an inflammatory response and hepatorenal impairment. The recovery rate was 82.8% in open pyometra cases, whereas 38.5% of the bitches with closed pyometra died, mainly due to sepsis and peritonitis. It is concluded that the type of pyometra directly influences clinical severity, the degree of systemic inflammation, and prognosis, highlighting the importance of early diagnosis and prompt surgical intervention.