What are the indications for plasma exchange in systemic lupus erythematosus (SLE)?

Indications for Plasma Exchange in Lupus

Plasma exchange in systemic lupus erythematosus (SLE) is primarily indicated for thrombotic microangiopathy (TMA) and catastrophic antiphospholipid syndrome (CAPS), with limited evidence supporting its use in other severe manifestations. 1

Primary Indications for Plasma Exchange in SLE

1. Thrombotic Microangiopathy (TMA)

Plasma exchange is indicated in SLE patients with TMA based on the underlying etiology:

• SLE-associated Thrombotic Thrombocytopenic Purpura (TTP)

  • Indicated when ADAMTS13 activity is low (<10%) 1
  • Treatment protocol: Plasma exchange + glucocorticoids + rituximab ± caplacizumab
  • Begin plasma exchange immediately in adults with moderate/high risk TTP (PLASMIC score >5) while awaiting test results 1
  • For children, consider deferring plasma exchange for 24-48 hours until ADAMTS13 results are available due to higher procedural risks 1

• Catastrophic Antiphospholipid Syndrome (CAPS)

  • Characterized by rapid-onset thrombosis affecting multiple organs with high mortality 1, 2
  • Treatment protocol: Triple therapy approach with plasma exchange + therapeutic anticoagulation + high-dose glucocorticoids 2
  • Early recognition and immediate initiation of this triple therapy is critical for improving survival 2

2. Diagnostic Approach for TMA in Lupus

1. Test for ADAMTS13 activity and antibodies to ADAMTS13
2. Test for antiphospholipid antibodies
3. Consider PLASMIC score to assess TTP risk while awaiting results
4. Start plasma exchange and glucocorticoids in adults with moderate/high risk while awaiting test results 1

Secondary Indications with Limited Evidence

Historical data and case reports suggest potential benefit in:

• Severe Neuropsychiatric SLE (NPSLE)

  • May be considered as adjunctive therapy for severe manifestations resistant to conventional treatment 3, 4
  • One retrospective study showed improvement in 13 NPSLE flares with a regimen combining corticosteroids, cyclophosphamide, and plasma exchange 4

• Diffuse Alveolar Hemorrhage

  • Considered in life-threatening cases as adjunctive therapy 3

• Refractory Lupus Nephritis

  • Limited evidence for efficacy as monotherapy 3, 5
  • A controlled trial showed no improvement in clinical outcomes when adding plasmapheresis to standard therapy (prednisone and cyclophosphamide) for severe lupus nephritis 6

Implementation Considerations

• Timing: Initiate immediately in suspected TTP or CAPS while awaiting diagnostic confirmation 1, 2
• Duration: For TTP, continue until clinical resolution and normalization of platelet count
• Monitoring: Regular assessment of platelet count, hemolysis markers, and organ function
• Co-management: When available, patients should be co-managed with an experienced hematologist 1

Important Caveats

• Plasma exchange rapidly removes autoantibodies but has a rebound effect without concurrent immunosuppression
• The 2024 KDIGO guidelines emphasize that plasma exchange should be used based on specific underlying pathology rather than as a general treatment for lupus 1
• Despite rapid improvement in some laboratory parameters (anti-dsDNA antibodies, immune complexes), clinical benefits may not always correlate 7
• For most manifestations of lupus, standard immunosuppressive therapy remains the cornerstone of treatment

Plasma exchange should be considered part of a targeted approach based on specific pathophysiologic mechanisms rather than as a general treatment for severe lupus.