Because cytologic or culture sample collection may induce erythema, you may be tempted to do vaginoscopy first. However, vaginoscopy
requires lubrication to introduce the instrument, so the vagina may be adulterated by the lubricant or by cells or debris
pushed into the vaginal vault with the vaginoscope, creating artifactual change in other diagnostic tests. I prefer to collect
all other samples first and perform vaginoscopy last, recognizing that artifactual changes may have occurred.
Vaginoscopy also helps you assess discharge present in the vaginal vault; vesicular lesions (e.g. seen with canine herpesvirus infection) or lymphoid follicles (e.g. seen as a nonspecific indicator of inflammation)16,17; urine pooling, which may be best identified by performing vaginoscopy in recumbent and standing patients9; masses; and foreign objects.
Other important diagnostic tests
Finally, a complete work-up for vaginitis in dogs, especially those with adult-onset disease, includes performing serologic
testing for canine brucellosis, which may be exhibited as persistent mucopurulent vulvar discharge,18 and ruling out systemic disease by performing a complete blood count and serum chemistry profile.
Canine herpesvirus infection in prepubertal bitches or spayed adult female dogs is associated with vesicular or firm lesions
on mucosal surfaces, including the vagina, and no other clinical signs.16,17 Unfortunately, tests for canine herpesvirus infection are imprecise and not clinically useful, so this infection may only
be suspected after other causes have been ruled out.19
How you treat an affected dog depends on the form of vaginitis present. Below is a summary of suggested therapies based on
the diagnostic findings.
In most bitches with juvenile vaginitis, physical and cytologic examinations reveal mucoid to mucopurulent vaginal discharge
and mild erythema in the vaginal vault, and vaginal bacterial cultures reveal no significant growth. Most cases will resolve
spontaneously with time, and conservative therapy is the norm. If the only clinical signs are those that you find incidentally,
treatment is not necessary. Excessive discharge or vulvar licking and marked growth of aerobic bacteria from a vaginal sample
warrant appropriate antibiotic therapy. Dogs may benefit from twice-daily cleaning of the perivulvar area with baby wipes
or a nonalcohol-based otic cleanser.9 Douching, or flushing of the vaginal vault, has not been reported to be an effective therapy in dogs with juvenile vaginitis.
A common question is, "Should dogs with juvenile vaginitis be allowed to go through one estrous cycle before ovariohysterectomy?"
No studies have evaluated whether this would be beneficial. In a retrospective study describing seven dogs with juvenile vaginitis
that were left intact, three improved after one estrous cycle, one improved after two estrous cycles, and three showed no
change after multiple estrous cycles but had subsequent resolution by 3 years of age.2 These results suggest that it may not be the hormonal changes and associated vaginal epithelial changes of estrus that resolve
the vaginitis but that a dog's increasing immunocompetence with maturity may be of benefit. The known increased incidence
of mammary neoplasia in bitches left intact is a strong incentive not to leave bitches intact as a treatment for vaginitis
unless severe clinical signs are present.
The most common primary problems reported in dogs with vaginitis are UTIs, reported in 26% to 60% of cases; vaginal anatomical
anomalies, reported in 20% to 36% of cases; and systemic disease, reported in 15% of cases.1,2
Be aware that in most bitches (73% in one study) vaginitis resolves regardless of the therapy used.2 I have had success in asking owners to keep track on a calendar when clinical signs are evident. This objective record better
permits the owner and the veterinarian to determine the frequency and severity of clinical signs and to monitor progress with
Bacterial infections. In some dogs, it is difficult to know whether vaginitis caused a UTI or if a UTI caused vaginitis. Concurrent bacterial cultures
of vaginal vault samples obtained by using a guarded vaginal swab and a urine sample collected by cystocentesis may permit
you to localize disease at the time of presentation.