A 45-year-old woman has progressive swelling of the right leg for two years. Examination shows non-pitting oedema, hyperkeratosis, and inability to pinch a fold of skin at the base of the second toe. Which investigation best distinguishes primary from secondary lymphoedema in this patient?
- A Duplex ultrasound of the deep venous system
- B CT scan of abdomen and pelvis ✓
- C Lymphoscintigraphy
- D Ankle-brachial index
Correct answer: B. CT scan of abdomen and pelvis
Explanation
The positive Stemmer sign (inability to pinch skin at the second toe base) confirms lymphoedema. In an adult with unilateral limb lymphoedema, pelvic malignancy with nodal metastases or prior radiotherapy is the leading cause of secondary disease, so cross-sectional imaging of the abdomen and pelvis identifies the cause. Lymphoscintigraphy confirms impaired lymphatic drainage but does not distinguish primary from secondary disease, and duplex excludes venous oedema instead.
Reference: Bailey and Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.