What is the management approach for a hemodialysis patient with an arteriovenous (AV) fistula, presenting with massive bilateral lower limb swelling, tenderness, fever, and ulceration on the dorsal aspect of both feet, despite a recent ultrasound scan showing no deep vein thrombosis (DVT)?

Management of Bilateral Lower Limb Swelling in Hemodialysis Patient with AV Fistula

This patient requires immediate fistulography to diagnose and treat central venous stenosis, which is the most likely cause of bilateral lower limb swelling in a hemodialysis patient with an AV fistula, despite negative DVT ultrasound. 1

Immediate Diagnostic Approach

Standard duplex ultrasound does not exclude central venous stenosis—the thoracic and pelvic central veins cannot be adequately visualized by ultrasound due to bony interference and overlying soft tissue, particularly in obese patients. 2, 1 The absence of DVT on ultrasound performed 5 days ago is insufficient to rule out the underlying pathology. 1, 3

Proceed directly to fluoroscopy fistulography within 48-72 hours, which serves as both the definitive diagnostic test and therapeutic intervention for central venous stenosis. 2, 1 This condition occurs in 5-50% of hemodialysis patients with vascular access and presents with the exact constellation of symptoms described: bilateral extremity edema, tenderness, warmth, and ulceration. 2, 1

Immediate Management (Within 24 Hours)

Infection Control

• Obtain blood cultures immediately before starting antibiotics given the 2-day fever history, bilateral tenderness, and temperature elevation. 1
• Start empiric broad-spectrum antibiotics covering Staphylococcus aureus and Streptococcus species to address the likely superimposed cellulitis/soft tissue infection contributing to the clinical picture. 1

Symptomatic Relief

• Elevate both lower extremities to reduce venous hypertension and swelling. 1
• Temporarily avoid dialysis through the AV fistula until central venous stenosis is confirmed or excluded, as the fistula may be exacerbating venous hypertension. 1

Swelling Beyond 2 Weeks Requires Central Vein Imaging

Since this patient has had swelling for 6 days, and guidelines specify that swelling persisting beyond 2 weeks after dialysis access placement requires venography or other noncontrast study to evaluate central veins, this patient is approaching that threshold. 2, 3 However, the presence of fever, ulceration, and bilateral involvement warrants more urgent evaluation. 1

Definitive Treatment During Fistulography

If hemodynamically significant stenosis (≥50% luminal narrowing) is identified, perform percutaneous transluminal angioplasty (PTA) immediately during the same procedure. 1, 4 This single-session approach allows for both diagnosis and treatment without delay. 2

Consider stent placement if acute elastic recoil occurs after angioplasty, as recommended for refractory stenoses. 1

Critical Pitfalls to Avoid

Do not delay fistulography beyond 48-72 hours—delay can lead to irreversible complications including permanent skin ulceration, access loss, or progression to sepsis. 1 The presence of bilateral foot ulceration indicates advanced venous hypertension that requires urgent intervention. 2, 1

Do not assume the negative ultrasound has ruled out all vascular pathology—central venous stenosis in the subclavian, brachiocephalic, or superior vena cava cannot be reliably detected by standard duplex ultrasound. 2, 1, 3

Do not dismiss bilateral presentation as simple volume overload—while hemodialysis patients commonly have fluid overload, the combination of bilateral swelling, tenderness, fever, and ulceration in a patient with an AV fistula strongly suggests central venous stenosis with superimposed infection. 1, 3

Anatomic Considerations

The most common sites of central venous stenosis in hemodialysis patients include the subclavian vein, brachiocephalic vein, and superior vena cava. 2, 4 Risk factors include history of prior central venous catheters, pacemakers, or other cardiac devices. 2 Even without documented prior catheter placement, the AV fistula itself can precipitate central venous stenosis. 2

Follow-Up Protocol

Reassess within 48-72 hours after intervention to evaluate clinical response and ensure no progression of infection or venous hypertension. 1

Continue regular monitoring after successful intervention, as central venous stenosis can recur and require repeat angioplasty. 1, 4

Monitor for development of venous collaterals on the chest wall or neck, which indicate significant central obstruction requiring immediate re-intervention. 2, 3

Anticoagulation Considerations

Do not initiate direct oral anticoagulants (DOACs) in this hemodialysis patient—there are insufficient data to support safe DOAC dosing in patients on hemodialysis, particularly for apixaban despite its FDA label not listing stage IV chronic kidney disease as a contraindication. 2 If anticoagulation becomes necessary after fistulography (e.g., if thrombosis is identified), unfractionated heparin is preferred as it is dialyzable and can be monitored with aPTT. 3