Context
Vaginal symptoms are one of the most common reasons for gynecological
consultation. Clinicians have traditionally diagnosed vaginal candidiasis,
bacterial vaginosis, and vaginal trichomoniasis using some combination of
physical examination, pH, the wet mount, and the whiff test.
Objectives
To evaluate the role of the clinical examination and determine the positive
and negative likelihood ratios (LRs) for the diagnosis of vaginal candidiasis,
bacterial vaginosis, and vaginal trichomoniasis.
Data Sources
Using a structured literature review, we abstracted information on sensitivity
and specificity for symptoms, signs, and office laboratory procedures. We
chose published (1966 to April 2003) articles that appeared in the MEDLINE
database and were indexed under the combined search terms of diagnosis with vaginitis, vaginal discharge, candidiasis, bacterial vaginosis, and trichomoniasis.
Study Selection
Included studies of symptomatic premenopausal women seen in primary
care settings. Tests were evaluated only if they would provide diagnostic
information during the office visit and were compared with an acceptable criterion
standard.
Data Extraction
All 3 authors extracted the data and computed sensitivity and specificity
from each article independently. The absence of standard definitions for symptoms
and signs made it impossible to combine results across studies.
Data Synthesis
Symptoms alone do not allow clinicians to distinguish confidently between
the causes of vaginitis. However, a patient's lack of itching makes candidiasis
less likely (range of LRs, 0.18 [95% confidence interval {CI}, 0.05-0.70]
to 0.79 [95% CI, 0.72-0.87]) and lack of perceived odor makes bacterial vaginosis
unlikely (LR, 0.07 [95% CI, 0.01-0.51]). Similarly, physical examination signs
are limited in their diagnostic power. The presence of inflammatory signs
is associated with candidiasis (range of LRs, 2.1 [95% CI, 1.5-2.8] to 8.4
[95% CI, 2.3-31]). Presence of a "high cheese" odor on examination is predictive
of bacterial vaginosis (LR, 3.2 [95% CI, 2.1-4.7]) while lack of odor is associated
with candidiasis (LR, 2.9 [95% CI, 2.4-5.0]). Office laboratory tests, particularly
microscopy of vaginal discharge, are the most useful way of diagnosing these
3 conditions.
Conclusions
The cause of vaginal complaints may be easily diagnosed when typical
findings appear in microscopy. However, the poor performance of individual
symptoms, signs, and office laboratory tests often makes it problematic to
identify the cause of vaginal symptoms.