Persistent hymen with pyovagina and pyometra.
Keywords: bovine, hymen, pyometra, heifer.A unique case.
A three year old Romagnola heifer in excellent body condition was presented with a history of infertility despite observations of repeated pasture breeding. An intermittent purulent discharge from the vagina was present. Transrectal palpation suggested the presence of fluid in the cranial vagina and uterus. This was not confirmed with ultrasonography because this case was presented in 1979, before the widespread use of diagnostic ultrasound in veterinary medicine. A tentative diagnosis of pyometra was made; highly unusual for a heifer.
Image size: 1443 x 996 px
The tract was examined after the heifer had been culled from the herd. As shown above, the cranial vagina and both uterine horns were distended with brown-to-yellow flocculent pus. A corpus luteum was present in the right ovary. This suggested that the heifer had been having estrous cycles or that luteolysis had failed in that ovary; the latter being likely in a cow with pyometra.
The tract was opened and examined. The image below shows the persistence of a hymen, particularly thick at its perimeter. There was a very small opening towards the center of the hymen, barely allowing the passage of a cotton swab. The caudal vestibule showed bright purple streaks of inflammation and congestion. The cervix (indicated by a yellow circle) was patent and pus could flow freely between the uterus and cranial vagina.
Notes: In heifers with persistent hymens, mucus and blood usually accumulate cranial to the hymen. The mucus arises from cervical gland secretions during estrus and the blood is the result of post-ovulation metrorrhagia (metestral hemorrhage). This fluid mixture accumulates in the cranial vagina of the heifer and often causing tenesmus (straining), especially when pressure is exerted on the dilated portion of the vagina during transrectal palpation. In dairy heifers there is the added history of an inability to perform artificial insemination.
In this case, it was likely that opportunistic bacteria resident in vestibule entered the cranial vagina through the small aperture in the hymen and established themselves in the excellent growth medium provided by the mucus/blood mixture in the cranial vagina. This would have resulted in pyovagina and as the infection moved cranially, pyometra as well. Culture of the pus was not performed in this case but it was most likely that Cornyebacterium pyogenes or later, that Actimomyces pyogenes would have been isolated. In subsequent years, the most likely candidate would have been Arcanobacterium pyogenes, and even more recently, Trueperella pyogenes. These are of course, one and the same bacterium but back in 1979, when taxonomists were smoking and cars used leaded gasoline, we knew no better.
References:
P.W. Farin, P.W. et al 1989 Effect of Actinomyces pyogenes and gram-negative anaerobic bacteria on the development of bovine pyometra P.W. Theriogenology. 31:979-989
Gahrn-Hansen. B and Frederiksen. W. 1992 Human infections with Actinomyces pyogenes (Corynebacterium pyogenes). Diag. Micro and Inf.Disease. 15: 349-354
Hadimili, H.H. 2010. Isolation of Arcanobacterium pyogenes from Samples of Sheep and
Cattle and Identification by Polimerase Chain Reaction. Kafkas Univ Vet Fak Derg. 16: 611-616
Semambo et al., 1991 Early abortion in cattle induced by experimental intrauterine infection with pure cultures of Actinomyces pyogenes.Vet. Record. 129:12–16
Yassin, A.F. et al. 2010. Comparative chemotaxonomic and phylogenetic studies on the genus Arcanobacterium Collins et al. 1982 emend. Lehnen et al. 2006: proposal for Trueperella gen. nov. and emended description of the genus Arcanobacterium. Int. J Systemic. Evolutionary Micro. 61: 1265-1274
