A case of urocolpos presenting as nocturnal enuresis

Clinical History

A 13-year-old prepubertal female patient was referred to us with a history of bed wetting since 3 years, which was aggravated over the last 3 months. The patient was normal previously and had normal bladder continence. No other related significant medical history was present.

Imaging Findings

On CECT abdomen, vagina appeared grossly distended with fluid (HU 10) and measures ~ 10 x 6 x 5 Cm (CC x Trans x AP). Uterus and cervix appeared pushed superiorly by the collection. There was no evidence of bladder diverticulum, ectopic ureter drainage and vesicovaginal fistula. A thin incomplete linear structure was also seen in the distal vagina- probably a partial hymen or a thin transverse vaginal septum. MR imaging of the pelvis done subsequently showed no abnormal vaginal collection; patient gave history of voiding 30 minutes before the MR study. Hence patient was asked to come the next day for ultrasound examination with full bladder. There was a vaginal collection of the size similar to the size on CT, which disappeared on voiding. Disappearance of the vaginal collection on post void images prompted a diagnosis of urocolpos due to vesicovaginal reflux, rather than an obstructive cause.

Discussion

Though minimal vaginal fluid can be seen occasionally in normal patients, distension of the vagina is uncommon, especially in adolescent patients.
Anatomic vaginal obstruction like imperforate hymen/vaginal agenesis/septum can cause hydro/ urocolpos. Leaking amniotic fluid in pregnant patients, misplaced bladder catheter and abnormal accumulation of urine are a few non obstructive causes [1].

Reflux of urine into vaginal vault during voiding represents vesicovaginal reflux.
It may cause enuresis or urinary tract infection. Causes are not exactly clear. Possible hypothesis include adhesions of labia minora, obesity causing significant labial apposition, abnormal meatal positioning (congenital female hypospadias) and functional cause like cerebral palsy/spastic pelvic floor muscles [2, 3, 4].

Incontinence, enuresis, urinary tract infections and vaginal discharge are the common manifestations of vesicovaginal reflux [5]. CT was done to rule out bladder diverticulum, ectopic ureter drainage and vesicovaginal fistula.

As the collection was large, obstructive hydrocolpos was considered initially; however, as the collection disappeared on post voiding images and there were no obvious local pathology, urocolpos due to vesicovaginal reflux is the most probable diagnosis in our patient. As our patient was overweight, labial apposition could be a contributing factor for vesicovaginal reflux. Any cross sectional modality (US, CT, MRI) with post void examination would be useful with CT being the best choice to rule out other possibilities. Voiding cystourethrography can also be useful as it would demonstrate active reflux when viewed under fluoroscopy [4].

Behavioral modification forms the most important part of the therapy. Various forms of behavioral treatments include positive reinforcement systems, self/parent awakening systems, daytime rehearsals and bed wetting alarms.

Disappearance of vaginal collection of any size following micturition, in the absence of other structural abnormalities nearly always clinches the diagnosis of vesicovaginal reflux with non obstructive urocolpos.

Differential Diagnosis List

Final Diagnosis

Urocolpos due to vesicovaginal reflux.

URL:	https://www.eurorad.org/case/10105
DOI:	10.1594/EURORAD/CASE.10105
ISSN:	1563-4086