What is the likely cause of a red, painful, inflamed area above the site of a recently removed intravenous (IV) port?

Likely Diagnosis: Superficial Thrombophlebitis or Catheter-Related Infection

This presentation is most consistent with superficial thrombophlebitis (inflammation of the vein with associated thrombus formation) or a localized catheter-related infection along the venous tract, both of which are well-recognized complications following IV catheter removal.

Clinical Reasoning

The key clinical features here are:

• Location: The inflamed area is 3 inches proximal to the former IV site 1
• Timing: Symptoms appeared 2 days after catheter removal 1
• Classic inflammatory signs: Redness, pain, swelling in a 1.5-inch diameter area 2, 3

These cardinal signs of inflammation (rubor, dolor, tumor) indicate an active inflammatory process that can result from either infectious or thrombotic etiologies 2, 3.

Most Likely Diagnoses

Superficial Thrombophlebitis (Primary Consideration)

Superficial thrombophlebitis is the most probable diagnosis given the proximal location along the venous tract. This occurs when:

• The catheter causes endothelial injury during its week-long placement 1
• Thrombus formation occurs along the vein wall 1
• Inflammation extends proximally from the insertion site after removal 1

The foot location is particularly relevant, as lower extremity IV access carries higher thrombotic risk 1.

Catheter-Related Infection (Important Differential)

A localized catheter-related infection must be considered, particularly:

• Exit-site infection extending proximally: Inflammation along the catheter tract with erythema and pain 1
• Tunnel infection: Though typically described for tunneled catheters, the concept applies—inflammation tracking along the venous pathway 1

The 2-day delay after removal makes active infection less likely than thrombophlebitis, but both can coexist 1.

Critical Assessment Steps

Immediate Evaluation Required

1. Examine for purulence or drainage: Any expressible purulence requires Gram stain and culture 1

2. Assess for systemic signs: Fever, chills, hypotension, or signs of sepsis suggest systemic infection requiring blood cultures 1

3. Evaluate extent of involvement:

   • Palpate the entire venous tract for cord-like induration (suggests thrombophlebitis) 1
   • Check for warmth extending beyond the visible erythema 2, 3

4. Rule out deep vein thrombosis: If swelling extends beyond the local area or involves the entire foot/leg, Doppler ultrasound is indicated 1

Diagnostic Workup

• If systemic symptoms present: Obtain paired blood cultures (peripheral and from any remaining vascular access) before starting antibiotics 1

• If localized symptoms only: Clinical diagnosis is usually sufficient for superficial thrombophlebitis 1

• If diagnostic uncertainty: Duplex ultrasound can confirm venous thrombosis and rule out deep involvement 1

Management Approach

For Superficial Thrombophlebitis (No Infection)

• Warm compresses to the affected area 1
• Elevation of the extremity 4
• NSAIDs for pain and inflammation 1
• Monitor for extension: Daily examination for proximal progression 1

If Infection Suspected (Purulence, Fever, or Systemic Signs)

• Obtain cultures before antibiotics: Swab any drainage and blood cultures if systemic symptoms 1

• Empiric antibiotics covering skin flora (Staphylococcus aureus, including MRSA consideration):

  • Ampicillin-sulbactam 3g IV every 6 hours for hospitalized patients 4
  • Clindamycin 600mg IV three times daily for penicillin allergy 4

• Source control: Ensure complete catheter removal (no retained fragments) 1

Common Pitfalls to Avoid

1. Dismissing as simple "irritation": The proximal location and 2-day delay suggest a pathologic process requiring monitoring 1

2. Missing deep vein involvement: Always assess for extensive swelling, which would require anticoagulation 1

3. Overlooking systemic infection: Check temperature and assess for sepsis signs, as catheter-related bloodstream infections carry 12-25% mortality 1

4. Inadequate follow-up: Re-examine in 24-48 hours to ensure no progression 1

Red Flags Requiring Urgent Intervention

• Fever or systemic symptoms: Immediate blood cultures and empiric antibiotics 1
• Rapid proximal extension: Consider deep vein thrombosis 1
• Purulent drainage: Culture and start antibiotics 1
• Severe pain out of proportion: May indicate necrotizing infection 4