Early pyometra or vaginitis
Keywords: pyometra, amoxicillin, antibiotics, cytology, metestrus, vaginitis, bacteria, anatomy, terminology
This image shows vaginal cytology from a three year old Pekingese with a history of a single litter (C-section). This bitch was presented 45 days post estrus with a purulent vulvar discharge. There was no evidence of pyometra on transabdominal US. Therefore this was assumed to be an early or transient case of pyometra or less likely, vaginitis.
Image size: 808 x 606 px
The bitch was treated with amoxicillin for 5 days and the discharge resolved uneventfully.
This image is presented because of its value in teaching two subjects: i. pyometra ii. the metestrus stage of the canine estrous cycle. With some variation in the number of bacteria present in each case, the cytology is similar i.e. parabasal cells and variable numbers of neutrophils.Discussion on terminology:
Should one refer to this condition as a vulvar, vaginal, or a vestibular discharge?
In general, a discharge is named for the orifice from whence it is issued. For example, pus from the uterus may form part of a cervical or vulvar discharge, two orifices from which it is usually observed. The vagina is a tube that connects those two orifices (the cervix and vulva) and is not an orifice itself from whence a discharge occurs. Therefore, this author does not support the use of the term "vaginal discharge".
If this pathology was observed as a vulvar (adjective) discharge what does the vulva consist of? Although part of the vulva is visible from the exterior, it extend cranially to the urethra. In fact, the vestibule is recognized as part of the vulva by some authors. Indeed, in humans, it is considered that all tissues caudal to the external urethral opening are parts of the vulva (noun). In veterinary terminology, the vulva is not usually considered to be part of the vestibule although, according to the etymology of the word, vestibule is derived from the Latin term for entrance. Therefore it is merely a matter of how long one considers the entrance to be and in a comical sense, does it include the front door (the vulva) or not? Rather laboriously then, it appears to be most correct to refer to the external observation in this case as being: "A discharge from the vulvar lips". With regard to the finding of the same discharge in the vagina, the condition should be referred to as "A cervical discharge".
Selected references
Nguyen J, Duong H 2020. Anatomy, Abdomen and Pelvis, Female External Genitalia . StatPearls Publishing, Treasure Island (FL).
Schlafer D.H. and Foster R. A. 2016 Jubb, Kennedy & Palmer's Pathology of Domestic Animals: Volume 3. : 358–464. Female Genital System
