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Fluid expressed
from self-collected tampons can be used for the diagnosis of
bacterial vaginosis.
Diagnosis of bacterial vaginosis on
self-collected tampon specimens.
Sturm PDJ, Moodley P, Nzimande G, Balkistan
R, Connolly C, Sturm AW.
Inter J STD
AIDS. 2002;13:559-563
Summary:
Question
Can vaginal tampon fluid be used for the microscopic diagnosis of
bacterial vaginosis (BV) in pregnant women?
Design
This study describes a direct, blinded comparison of the microscopic
evaluation of Gram stains made from vaginal swab samples and from
different tampon fluid preparations with the Amsel criteria for the
diagnosis of bacterial vaginosis.
Participants
Sixty-four randomly recruited new admissions to a hospital obstetric ward
in Durban, South Africa were studied. Women were excluded if they had
apparent labor, cervical insufficiency, vaginal bleeding, placenta previa,
or T. vaginalis infection. The mean age was 28 years and the mean
gestational age was 32 weeks.
Description of Tests and Diagnostic
Standard
A vaginal tampon was inserted, left in place for 15 to 30 minutes, placed
in 10 ml of phosphate buffered saline, and expressed with a tongue
depressor within one hour. Drops of the unconcentrated fluid, and of fluid
obtained by cytospinning 25 and 50 l aliquots, were air dried on slides. A
vaginal swab was obtained and used to make a slide. All the slides were
Gram stained and evaluated independently by two observers for the presence
of BV-related bacteria using the Nugent scoring system. A score of >6
was defined as positive for BV. The women were also assessed for BV using
the Amsel criteria as the diagnostic standard.
Main Outcome Measures
The sensitivity and specificity of the Nugent score on slides made from
tampon fluid and from swabs for the diagnosis of BV as determined by the
Amsel criteria were calculated.
Main Results
BV was diagnosed in 21% of the women using the Amsel criteria and in 29%
and 26% of the women using the Nugent score on the vaginal smears by
observers 1 and 2, respectively. The test parameters of the Nugent score
when performed on vaginal smears and on the different tampon fluid
preparations, using the Amsel criteria as the reference standard, are
shown in the table. There were no significant differences between the
different tampon fluid preparations or the vaginal smear in the
sensitivity and specificity of the Nugent score for the diagnosis of BV.
| Test parameters of
the Nugent score on smear and tampon fluid preparations for the
diagnosis of BV defined by the Amsel criteria |
| Preparation |
Sensitivity
(%) |
Specificity
(%) |
| Observer
1 |
Observer
2 |
Observer
1 |
Observer
2 |
| Vaginal
smear |
83 |
94 |
80 |
80 |
| Tampon,
unconcentrated |
94 |
89 |
78 |
80 |
| Tampon,
25 μl cytospin |
100 |
89 |
74 |
80 |
| Tampon,
50 μl cytospin |
94 |
89 |
80 |
80 |
Authors' Conclusions
Fluid from a self-administered,
self-collected vaginal tampon can be used for the diagnosis of BV using
the Nugent score.
Source of funding: The Wellcome Trust
For correspondence: A. W. Sturm,
Medical School, 719 Umbilo Road, Durban 4001, South Africa. E-mail
address: sturm@nu.ac.za
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