Fig. 4

a-d Pyometra. Uterus from an 8 year old bitch. The uterus increased considerably, horns entirely filled with surging purulent secretions. a Macroscopic image, longitudinal incision of the uterine horns. Macroscopically endometrium damaged, presenting significant degenerative changes. A number of differently sized cysts on the surface of the endometrium were observed, most of them already ruptured. b, c, d H&E stained histological images of transverse uterine horn fragment. Chronic, purulent endometritis, with places of lymphoplasmacytic infiltration has been observed. Inflammation of a severe degree occurred in the muscular layer. Multifocal cystic endometrial hyperplasia (arrows) occurred as well as adenomyosis and mild multifocal endometrial fibrosis (triangles). Neutrophils infiltrate the lumen of the endometrial glands (asterisks). Magnification: b 20x; c 100x, d 400x