Lupus Nephritis

See Also

Systemic Lupus Erythematosus

Epidemiology

Renal disease or Lupus Nephritis is ultimately present in 50 to 60% of SLE cases

Grading

Class 1: Minimal Mesangial (earliest and most mild form)
1. Minimal Proteinuria
2. Normal Serum Creatinine
3. Histology with immune complex deposition on immunofluorescence, but otherwise normal glomeruli
Class 2: Mesangial Proliferative
1. Microscopic Hematuria with or without Proteinuria
2. Histology with mesangial matrix expansion and immune complex deposition
Class 3: Focal Lupus Nephritis
1. Microscopic Hematuria
2. Proteinuria (Nephrotic Syndrome may be present)
3. Hypertension
4. eGFR decreased
5. Histology with Glomerulonephritis (focal, segmental or global) affecting <50% of glomeruli
Class 4: Diffuse Lupus Nephritis (most common)
1. Includes Class 3 features
2. Complement C3 low
3. Anti-Double Stranded DNA Antibody (dsDNA) elevated
4. Histology with Glomerulonephritis affecting >50% of glomeruli and subendothelial diffuse immune deposits
  1. Diffuse Segmental Subtype (4S): Segmental lesions affecting >50% of glomeruli
  2. Diffuse Global Subtype (4G): Global lesions affecting >50% of glomeruli
  3. Subtypes may be further characterized: Active, Active and chronic, and Inactive with glomerular scar
Class 5: Membranous Nephropathy
1. Nephrotic Syndrome
2. Microscopic Hematuria
3. Hypertension
4. Serum Creatinine normal
5. Membranous Nephropathy may be the only SLE manifestation, and may occur combined with Class 3 ot 4
6. Histology with subepithelial immune deposits (global or segmental)
Class 6: Advanced Sclerosing Lupus
1. Slowly progressive Chronic Kidney Disease to end-stage Renal Failure
2. Proteinuria with otherwise negative Urine Microscopic Exam
3. Histology with global sclerosis affecting >90% of glomeruli

Labs

Screening in Systemic Lupus Erythematosus patients (without diagnosed renal disease)
1. Screen Urinalysis and Serum Creatinine every 3-6 months
2. Reflex abnormal findings to Urine Protein to Creatinine Ratio
Renal biopsy indications
1. Proteinuria >=1 g per 24 hours OR
2. Hematuria > 0.5 g per 24 hours OR
3. Cellular Casts

Management

General
1. See Prevention of Kidney Disease Progression
2. Consult nephrology and Rheumatology
Class 1 and 2
1. Renin-Angiotensin System agents (e.g. ACE Inhibitors or Angiotensin Receptor Blockers)
Class 3, 4 and 5
1. Induction Phase
  1. Pulse IV Corticosteroids AND
  2. Cyclophosphamide IV for 6 doses (over 3-6 months) OR Mycophenolate daily for 6 months
    1. Cyclosporine or Tacrolimus may be used as alternative in Class 5 disease
2. Maintenance Phase
  1. Wean Corticosteroids to lowest effective dose
  2. Longterm Mycophenolate or Aziothioprine
Class 6
1. Renin-Angiotensin System agents (e.g. ACE Inhibitors or Angiotensin Receptor Blockers)
2. Prepare for renal replacment therapy (e.g. Hemodialysis, Renal Transplant)

Resources

Lupus Nephritis (StatPearls)
1. https://www.ncbi.nlm.nih.gov/books/NBK499817/

References