Lupus Nephritis

Lupus Nephritis is a topic covered in the 5-Minute Clinical Consult.

To view the entire topic, please or .

Medicine Central™ is a quick-consult mobile and web resource that includes diagnosis, treatment, medications, and follow-up information on over 700 diseases and disorders, providing fast answers—anytime, anywhere. Explore these free sample topics:

-- The first section of this topic is shown below --

Basics

Description

  • The renal manifestation of systemic lupus erythematosus (SLE)
  • American College of Rheumatology (ACR) criteria: persistent proteinuria >500 mg/day or ≥3 on dipstick and/or presence of cellular casts; alternatively, spot urine protein-to-creatinine ratio >0.5 and “active urinary sediment” (>5 red blood cell [RBC]/ high-power field [HPF], >5 white blood cell [WBC]/HPF in absence of infection, or cellular casts—RBC or WBC casts) (1)
  • Clinical manifestations primarily due to immune complex–mediated glomerular disease. Tubulointerstitial and vascular involvement often coexist. Diagnosis is based on clinical findings, urine abnormalities, autoantibodies, and renal biopsy.
  • Treatment and prognosis depend on International Society of Nephrology/Renal Pathology Society (ISN/RPS) histologic class—risk of end-stage renal disease (ESRD) highest in class IV.
  • Delay in diagnosis/treatment increases risk of ESRD. Early diagnosis improves renal outcomes.

Epidemiology

  • Peak incidence of SLE is 15 to 45 years of age. Mean age of diagnosis is between 25 and 30 years of age.
  • Predominant sex: female > male (10:1)
  • Once SLE develops, lupus nephritis (LN) affects both genders equally; it is more severe in children and men and less severe in older adults.
  • More common in African American and Asian populations.

Incidence
  • SLE: 1.4 to 22/100,000
  • Up to 60% of SLE patients develop LN over time; 25–50% of SLE patients have nephritis as the initial presentation.

Pediatric Considerations
LN is more common and more severe in children: 60–80% of children have LN at or soon after SLE onset.

Prevalence
SLE: 7.4 to 159.4/100,000

Etiology and Pathophysiology

  • Immune complex–mediated inflammation injures glomeruli, tubules, interstitium, and vasculature.
  • Glomeruli: Varying degrees of mesangial proliferation, crescent formation, and fibrinoid necrosis cause reduced glomerular filtration rate (GFR).
  • Persistent inflammation (chronicity) leads to sclerosis and glomerular loss.
  • Tubulointerstitial injury (edema, inflammatory cell infiltrate acutely; tubular atrophy in chronic phase) with or without tubular basement membrane immune complex deposition leads to reduced renal function.
  • Vascular lesions: immune complex deposition and noninflammatory necrosis in arterioles
  • SLE is a multifactorial disease, with multigenic inheritance; exact etiology remains unclear.
  • Defective T-cell autoregulation and polyclonal B-cell hyperactivity contribute to dysregulated apoptosis. Impaired clearance of apoptotic cells inhibits self-tolerance to nuclear antigen.
  • Anti-DNA, anti-C1q, anti–α-actin, and other nuclear component autoantibodies develop.
  • Deposition of circulating immune complexes or autoantibodies attaching to local nuclear antigens leads to complement activation, inflammation, and tissue injury.
  • Interaction of genetic, hormonal, and environmental factors leads to great variability in LN severity.

Genetics
  • Polygenic inheritance; clustering in families, ~25% concordance in identical twins
  • Interaction of general SLE susceptibility genes with more renal-specific genes and epigenetic changes

Risk Factors

Younger age, African American or Hispanic race, more ACR criteria for SLE, longer disease duration, hypertension, lower socioeconomic status, family history of SLE, anti-dsDNA antibodies, low albumin to globulin ratio

Commonly Associated Conditions

Skin, hematologic, cerebral, pulmonary, GI, and cardiopulmonary systems are often involved in SLE.

-- To view the remaining sections of this topic, please or --

Basics

Description

  • The renal manifestation of systemic lupus erythematosus (SLE)
  • American College of Rheumatology (ACR) criteria: persistent proteinuria >500 mg/day or ≥3 on dipstick and/or presence of cellular casts; alternatively, spot urine protein-to-creatinine ratio >0.5 and “active urinary sediment” (>5 red blood cell [RBC]/ high-power field [HPF], >5 white blood cell [WBC]/HPF in absence of infection, or cellular casts—RBC or WBC casts) (1)
  • Clinical manifestations primarily due to immune complex–mediated glomerular disease. Tubulointerstitial and vascular involvement often coexist. Diagnosis is based on clinical findings, urine abnormalities, autoantibodies, and renal biopsy.
  • Treatment and prognosis depend on International Society of Nephrology/Renal Pathology Society (ISN/RPS) histologic class—risk of end-stage renal disease (ESRD) highest in class IV.
  • Delay in diagnosis/treatment increases risk of ESRD. Early diagnosis improves renal outcomes.

Epidemiology

  • Peak incidence of SLE is 15 to 45 years of age. Mean age of diagnosis is between 25 and 30 years of age.
  • Predominant sex: female > male (10:1)
  • Once SLE develops, lupus nephritis (LN) affects both genders equally; it is more severe in children and men and less severe in older adults.
  • More common in African American and Asian populations.

Incidence
  • SLE: 1.4 to 22/100,000
  • Up to 60% of SLE patients develop LN over time; 25–50% of SLE patients have nephritis as the initial presentation.

Pediatric Considerations
LN is more common and more severe in children: 60–80% of children have LN at or soon after SLE onset.

Prevalence
SLE: 7.4 to 159.4/100,000

Etiology and Pathophysiology

  • Immune complex–mediated inflammation injures glomeruli, tubules, interstitium, and vasculature.
  • Glomeruli: Varying degrees of mesangial proliferation, crescent formation, and fibrinoid necrosis cause reduced glomerular filtration rate (GFR).
  • Persistent inflammation (chronicity) leads to sclerosis and glomerular loss.
  • Tubulointerstitial injury (edema, inflammatory cell infiltrate acutely; tubular atrophy in chronic phase) with or without tubular basement membrane immune complex deposition leads to reduced renal function.
  • Vascular lesions: immune complex deposition and noninflammatory necrosis in arterioles
  • SLE is a multifactorial disease, with multigenic inheritance; exact etiology remains unclear.
  • Defective T-cell autoregulation and polyclonal B-cell hyperactivity contribute to dysregulated apoptosis. Impaired clearance of apoptotic cells inhibits self-tolerance to nuclear antigen.
  • Anti-DNA, anti-C1q, anti–α-actin, and other nuclear component autoantibodies develop.
  • Deposition of circulating immune complexes or autoantibodies attaching to local nuclear antigens leads to complement activation, inflammation, and tissue injury.
  • Interaction of genetic, hormonal, and environmental factors leads to great variability in LN severity.

Genetics
  • Polygenic inheritance; clustering in families, ~25% concordance in identical twins
  • Interaction of general SLE susceptibility genes with more renal-specific genes and epigenetic changes

Risk Factors

Younger age, African American or Hispanic race, more ACR criteria for SLE, longer disease duration, hypertension, lower socioeconomic status, family history of SLE, anti-dsDNA antibodies, low albumin to globulin ratio

Commonly Associated Conditions

Skin, hematologic, cerebral, pulmonary, GI, and cardiopulmonary systems are often involved in SLE.

There's more to see -- the rest of this entry is available only to subscribers.