Adolescent, Vaginal Discharge, Trichomonas
Abnormal vaginal discharge and dysuria suggest the presence of coexisting
infection of the genital tract (eg, vaginitis or cervicitis) and urethra (eg,
urethritis) or vaginitis that has produced vulvar inflammation with resulting
discomfort during urination (external dysuria). The etiology of the infection is
determined best by performing a gynecologic examination that includes collection
of vaginal secretions for microscopic examination and
endocervical
swabs for testing for infection with Chlamydia
trachomatis
and Neisseria
gonorrhoeae.
The presence of motile, flagellated organisms, as observed in the patient in the
vignette,
indicates infection with
Trichomonas
vaginalis.
T vaginalis is transmitted almost
exclusively by sexual contact, although it can survive for as long as 45 min on
toilet seats, washcloths, and clothing and in bath water, suggesting the
possibility of nonsexual acquisition. Approximately
20% to 50% of infected women have
symptoms, including yellow vaginal discharge,
vulvar
inflammation and
pruritus,
dysuria,
and occasionally abdominal pain. Dysuria may result from coexisting
urethral infection or from discomfort associated with the contact of urine with
inflamed vulvae. On physical examination, the
vulvae often appear
erythematous and edematous, and
the vagina is
erythematous with a
yellow or green, frothy
discharge. Punctate cervical hemorrhages, referred to as
"strawberry cervix" or "colpitis
macularis,"
are highly specific for
trichomoniasis but are observed only in
a minority of infected patients. Although lower abdominal tenderness to
palpation, possibly due to severe vaginitis or regional lymphadenopathy, has
been reported in some women, the presence of this symptom should raise concern
about coexisting pelvic inflammatory disease due to C trachomatis, N gonorrhoeae,
or other organisms.
The diagnosis of trichomoniasis in women generally is confirmed by
finding motile, flagellated organisms
on microscopic examination of vaginal secretions. Although rapid and
inexpensive, this method has a diagnostic
sensitivity of only 50% to 70%.
Culture methods improve sensitivity but are more expensive and not employed
routinely in most clinical settings.
The treatment for trichomoniasis is oral
metronidazole
2 g as a single dose for the patient and her
partner(s).
This simultaneous treatment plan results in a 95% cure rate. For patients who do
not respond to single-dose therapy, oral metronidazole may be prescribed at a
dose of 500 mg bid for 7 days.
Because of concerns about potential mutagenicity, it has been
suggested that
metronidazole
not be used
during pregnancy. Existing data suggest, however, that the mutagenic risk
associated with short-term, low-dose therapy is extremely low. In view of this,
some experts, including the Centers for
Disease Control and Prevention, state that pregnant women who have
trichomoniasis
may be treated with a single 2 g dose of
metronidazole.
Oral
azithromycin
(1 g once) or doxycycline
(100 mg bid for 7 days) may be used to treat uncomplicated
chlamydial
infection of the cervix. For women who have
uncomplicated
gonococcal
cervical infection, oral cefixime
(400 mg once) or ciprofloxacin (500 mg once) are effective. Although the
patient in the vignette has trichomoniasis, appropriate diagnostic testing for
other sexually transmitted infections (eg. chlamydia, gonorrhea, and syphilis)
is warranted because she may beconcomitantly infected with other sexually
transmitted pathogens. However, treatment for these pathogens is not indicated
unless diagnostic testing shows evidence of infection.
References:
Centers for Disease Control and Prevention. 1998 guidelines for the
treatment of sexually transmitted diseases. MMWR Morb Mortal Wkly Rep.
1998;47(RR-1):1-111
Emans SJ, Laufer MR, Goldstein DP. Trichomonal vaginitis. Pediatric
and Adolescent Gynecology. 4th ed. Philadelphia, Pa: Lippincott-Raven;
1998:430-431
Krieger JN, Alderete JF. Trichomonas vaginalis and trichomoniasis. In:
Holmes KK, Sparling PF, Mardh PA, et al, eds. Sexually Transmitted
Diseases. 3rd ed. New York, NY: McGraw-Hill; 1999:587-604
Lappa S, Moscicki AB. The pediatrician and the sexually active
adolescent. A primer for sexually transmitted diseases. Pediatr Clin
North Am. 1997;44:1405-1445