Lichen sclerosus is a chronic inflammatory disease affecting primarily the anogenital region and may cause symptomatic labial agglutination. We describe an unusual presentation of this condition in a postmenarchal, virginal girl. A 14 year-old girl presented to the Emergency Department of a tertiary children's hospital with acute urinary retention. A perineal inspection revealed labial fusion starting anteriorly and covering up almost two third of the introitus (Figure 1A). Because she was able to void during the assessment period in the Emergency Department, her labial adhesions were managed conservatively with topical estrogen and sitz baths. Ten days after initial presentation, she developed acute onset abdominal pain with fever. Abdominal ultrasound and magnetic resonance imaging revealed tubo-ovarian abscesses mainly in the right ovary and both fallopian tubes (Figure 2A and 2B). The patient was admitted to the hospital and started on intravenous antibiotherapy according to recommendations of infectious diseases specialists. Since adequate clinical response was not achieved with optimal medical treatment, drainage of bilateral tubo-ovarian abscesses was done by the interventional radiology under general anesthesia. In the same session, a simple division of the labial agglutination and vulvar biopsies were performed by the pediatric and adolescent gynecology team with a preliminary diagnosis of vulvar lichen sclerosus based on the clinical features of the patient (Figure 1B). Pathology, although not conclusive, supported the clinical impression. During her inpatient follow up, a second imaging-guided abscess drainage was required, four days after the first procedure, due to insufficient clinical improvement and residual right tubo-ovarian abscess detected on repeated abdominal magnetic resonance. After 3 weeks of intravenous antibiotherapy, the patient was discharged with oral antibiotics and clobetasol propionate 0.05% ointment for local treatment of the lichen sclerosus. The outpatient follow up has gone uneventfully and no recurrence of labial agglutination has been observed. The proposed mechanism for this rare complication of vulvar lichen sclerosus is vaginal pooling of urine due to significant labial agglutination, leading to ascending infection, pelvic inflammatory disease and tubo-ovarian abscesses. In conclusion, vulvar lichen sclerosus should be considered in cases of labial agglutination with atypical findings such as older age and anterior location. Finally, this rare presentation of vulvar lichen sclerosus reminds us that pelvic inflammatory disease and tubo-ovarian abscess must be kept in mind in the presence of fever, abdominal pain and adnexal mass, even in virginal adolescents. The existence of obstructive lesions of the genital tract should further increase the suspicion for these infections.Figure 2A and B. Pelvic MRI showing the tubo-ovarian abscessesView Large Image Figure ViewerDownload Hi-res image Download (PPT)