Detailed Pathophysiological Investigation of Canine Pyometra and the Curative Role of Ovariohysterectomy

Background: Pyometra or cystic endometrial hyperplasia complex in dogs is a hormonally mediated bacterial disease wherein middle-aged bitches are most affected. The current study was carried out in pyometra-affected bitches to determine the alterations in hormonal, histopathological and haemato-biochemical profiles after 14 days of ovariohysterectomy. Methods: Blood samples were collected both from control (n=15) and affected bitches (n=15) showing signs of open cervix pyometra preoperatively and postoperatively on the day of surgery, on the 7th and 14th day after ovariohysterectomy. Blood samples were subjected to the estimation of endocrinological and hematobiochemical parameters. The ovary, oviduct and uterus were collected for gross and histological observations.
Result: The pre-operative serum progesterone (ng/ml) recorded in bitches affected with pyometra were 9-fold higher than controls (9.77±2.64 vs 0.61±0.66) (P less than 0.01). There was a non-significant difference in the pre-operative (414.63±62.88) and post-operative (390.6±54.20) estrogen concentration and the results indicated a presence of an extragonadal source of estrogen. The enormous endometrial lumen of these cysts contained eosinophilic hazy granular material and tissue debris along with massive infiltration of inflammatory cells, predominantly neutrophils. The findings of the study revealed that progesterone is the major contributory factor and extragonadal sources of estrogen may be present along with hyperplastic changes in the uterine and glandular epithelium in pyometra-affected bitches.
