What is the next step in evaluating a postmenopausal patient with a history of total hysterectomy, diabetes, and breast cancer, who presents with vaginal discharge, and for whom I have ordered an ultrasound (u/s) transvaginal?

Next Steps After Ordering Transvaginal Ultrasound in This Patient

In a postmenopausal patient with prior total hysterectomy presenting with vaginal discharge, the transvaginal ultrasound you ordered is not the appropriate imaging study, as there is no uterus or endometrium to evaluate—instead, focus your clinical assessment on the vaginal vault, ovaries, and potential non-uterine sources of discharge. 1

Why Transvaginal Ultrasound Has Limited Utility Here

• The primary indication for transvaginal ultrasound in postmenopausal patients is to evaluate the endometrium in those with vaginal bleeding, where an endometrial thickness ≤4 mm has a >99% negative predictive value for endometrial cancer 1
• This patient has no uterus, so endometrial assessment is impossible and the main diagnostic value of transvaginal ultrasound in postmenopausal bleeding is eliminated 1, 2
• Transvaginal ultrasound can still visualize the ovaries and vaginal vault, which may provide some diagnostic information about the source of discharge 2, 3

What the Ultrasound Can Still Assess

• Evaluate the ovaries for masses or cysts that could be contributing to symptoms, particularly given the patient's history of breast cancer (which raises concern for potential ovarian metastases or hormone-related pathology) 4, 2
• Assess the vaginal vault for fluid collections, masses, or abscesses that could explain purulent or pathologic discharge 3, 5
• Look for pelvic inflammatory disease or tubo-ovarian pathology if the patient still has ovaries and fallopian tubes, as thick-walled echogenic tubes (≥5 mm) suggest pyosalpinx 5

Critical Next Steps Based on Discharge Characteristics

If the discharge is purulent:

• Perform a thorough pelvic examination with speculum to identify the source (vaginal vault, cervical stump if present, or vulvar/perineal origin) 6
• Obtain cultures and consider empiric antibiotic therapy for suspected pelvic inflammatory disease or vaginal vault infection 5
• Do not assume infection is the sole explanation—more aggressive evaluation may be needed depending on clinical presentation 7

If the discharge is bloody or serous (pathologic):

• This raises concern for malignancy, particularly vaginal vault recurrence or ovarian pathology given her breast cancer history 8, 1
• The ultrasound findings must be correlated with physical examination to identify any vaginal vault masses or lesions 6, 3
• If ultrasound shows an ovarian mass with complex features (solid and cystic components, internal echoes, septations), this is highly suggestive of malignancy and requires further workup 4

When to Escalate Imaging

• If the transvaginal ultrasound is normal but symptoms persist, consider MRI of the pelvis without and with contrast for superior soft tissue characterization 4, 6
• MRI provides excellent visualization of the vaginal vault, pelvic floor, and any residual pelvic structures that may be difficult to assess on ultrasound 4, 6
• For suspected ovarian malignancy with indeterminate ultrasound findings, MRI increases diagnostic specificity and can help distinguish benign from malignant lesions 4

Common Pitfalls to Avoid

• Do not dismiss non-bloody discharge as benign—serous and other colored discharges can still indicate serious pathology 8
• Do not forget that this patient's diabetes increases her risk for infectious complications including vaginal vault abscesses 5
• Do not overlook the breast cancer history—metastatic disease to the ovaries or vaginal vault is possible and requires high clinical suspicion 4
• Physical examination remains the foundation for evaluating vaginal and vulvar pathology, which imaging may not adequately characterize 6