Can plasmapheresis cause leukocytosis (elevated white blood cell count)?

Can Plasmapheresis Cause Leukocytosis?

Yes, plasmapheresis can cause leukocytosis as a complication of the procedure, though it is not among the most commonly reported adverse effects. While the European Respiratory Society guidelines and other evidence do not specifically highlight leukocytosis as a primary complication of plasmapheresis, the procedure can trigger various physiological responses that may lead to elevated white blood cell counts.

Mechanism and Evidence for Plasmapheresis-Induced Leukocytosis

Plasmapheresis may lead to leukocytosis through several potential mechanisms:

1. Inflammatory Response: The extracorporeal circulation and contact of blood with foreign surfaces during plasmapheresis can trigger an inflammatory response, potentially leading to leukocytosis.

2. Stress Response: Physical stress from the procedure itself can elevate white blood cell counts, as noted in general leukocytosis assessment principles 1.

3. Demargination: The procedure may cause demargination of white blood cells from the vascular endothelium into circulation.

Common Complications of Plasmapheresis

According to the European Respiratory Society guidelines, the most frequently reported complications of plasmapheresis include 2:

• Fall in arterial blood pressure (8.4% of procedures)
• Arrhythmias (3.5%)
• Sensations of cold with temporarily elevated temperature (1.1%)
• Paresthesias (1.1%)

More severe complications occur in approximately 2.16% of procedures, including:

• Shock
• Severe hypotension requiring vasopressors
• Persistent arrhythmias
• Hemolysis

A Cochrane meta-analysis cited in the guidelines evaluated plasmapheresis safety in Guillain-Barré syndrome and found no increased risk of 2:

• Infection (RR 0.91 [0.73,1.13])
• Blood pressure instability (RR 0.88 [0.64,1.22])
• Cardiac arrhythmias (RR 0.75 [0.56,1.00])
• Pulmonary embolism (RR 1.01 [0.26,4.00])

Hematological Effects of Plasmapheresis

Plasmapheresis can affect blood cell counts in various ways:

1. Platelet Effects: Research has demonstrated that plasmapheresis can cause unintentional platelet removal, with loss ranging from 0 to 71% depending on the equipment used 3. This suggests that the procedure can significantly impact blood cell components.

2. White Blood Cell Effects: While specific data on leukocytosis is limited in the guidelines, the procedure's known effects on other blood components and its ability to trigger inflammatory responses suggest it could potentially cause leukocytosis.

3. Cardiovascular Effects: A study examining plasmapheresis in septic shock patients found no significant changes in white blood cell counts after the procedure 4, though this was in a specific patient population already experiencing inflammatory responses.

Management Considerations

If leukocytosis occurs following plasmapheresis:

1. Assess Severity: Determine the degree of leukocytosis and whether it's causing symptoms.

2. Rule Out Other Causes: Consider other potential causes of leukocytosis, including:

   • Underlying disease process
   • Concurrent infections
   • Medication effects
   • Stress response

3. Monitor: Regular complete blood counts with differential to track the white blood cell count and composition.

4. Supportive Care: Most cases of procedure-related leukocytosis are self-limiting and resolve without specific intervention.

Clinical Implications

The potential for leukocytosis should not generally contraindicate plasmapheresis when clinically indicated. The European Respiratory Society guidelines note that plasmapheresis is well-tolerated with adverse events that can be anticipated and avoided 2. The mortality associated with plasmapheresis is estimated to be very low (0.05%) based on a systematic review of over 15,500 patients 2.

For patients requiring plasmapheresis, continuous observation and proper monitoring by trained medical personnel are essential for safety 5.