Vaginal Cyst

A vaginal cyst is a closed, fluid-filled or keratin-filled sac in the vaginal wall. It arises from embryonic remnants, epithelium trapped after injury, or blocked glands.

• Types are Müllerian (paramesonephric) cysts, Gartner duct (mesonephric) cysts, epidermal inclusion cysts and, rarely, endometriotic cysts.
• Most are small, benign and found incidentally on speculum examination.
• Large cysts can cause dyspareunia, difficulty with tampons and obstruction of vaginal delivery.

Many women have no symptoms. A smooth, round, mobile swelling 1 to 5 cm in size is felt in the vaginal wall.

• Vaginal fullness, dyspareunia, urinary frequency or incomplete emptying when the cyst presses on the bladder or urethra.
• Cysts of the lateral wall are usually Gartner duct cysts and cysts of the anterior wall are often Müllerian cysts.
• Differential diagnosis: cystocele, rectocele, urethral diverticulum, Skene gland cyst, Bartholin cyst, vaginal prolapse, vaginal tumour, ectopic ureterocele.
• Complications: infection, abscess, dyspareunia, urinary obstruction, recurrence and rarely malignant change.

Diagnosis is by speculum and bimanual examination.

• Transvaginal or translabial ultrasound defines the size, wall and contents.
• Pelvic MRI separates a cyst from a urethral diverticulum and shows its relation to the urethra and bladder neck.
• Renal tract ultrasound for lateral wall cysts, because Gartner duct cysts may be linked to renal anomalies.
• Histology of the cyst wall after excision; biopsy of any solid or irregular area.

Observe small asymptomatic cysts and excise cysts that are symptomatic or enlarging.

• Supportive: reassure that small asymptomatic cysts are benign and need no treatment; warm sitz baths 10 to 15 minutes, 3 times daily for discomfort; avoid tampons if painful.
• Pharmacological: paracetamol 1 g oral 6-hourly (maximum 4 g in 24 hours) for pain. Infected cyst: amoxicillin-clavulanate 625 mg oral 8-hourly for 5 to 7 days, or clindamycin 300 mg oral 8-hourly for 5 to 7 days in penicillin allergy.
• Procedures: observation for asymptomatic cysts. Symptomatic or enlarging cysts: complete excision under regional or general anaesthesia with absorbable 3-0 sutures to close the dead space, taking care to avoid the urethra, bladder and rectum. Marsupialisation when the cyst is deep or close to the urethra. Needle aspiration alone is not advised because the cyst recurs.
• Special groups: in pregnancy leave small cysts alone; a cyst that obstructs labour needs drainage or caesarean delivery, and elective excision is deferred until after delivery.
• Red flags: rapid growth, solid component, bleeding, fixed mass, fever with pain, urinary retention.
• Follow-up: review at 2 weeks after surgery and at 3 months; histology result review; yearly examination if observed.