The Lupus Kidney Disease Update

**21**

**Chapter 2**

**Abstract**

aspects.

**1. Introduction**

Lupus Nephritis: Renal Biopsy

*Rosa Marlene Viero and Daniela Cristina dos Santos*

Systemic lupus erythematosus is a chronic autoimmune disease that affects mostly women. The kidneys are involved in 50% of patients causing a high degree of disease morbidity and mortality with poor prognosis. Early diagnosis of lupus nephritis with prompt therapy correlates with a better outcome. The renal biopsy provides important informations to clinicians to monitor the patients. The patterns of glomerular lesion, degree of activity and chronicity of the disease and extent of lesions to the tubulointerstitial and vascular compartments are fundamental information for the clinician to decide the most appropriate treatment. In order to correlate the kidney disease with clinical manifestations and patient outcome the glomerular lesions are classified according to International Society of Nephrology and Renal Pathology Society Classification (ISN/RPS). The definition of active and chronic lesions was introduced by studies conducted at National Institute of Health (NIH). The ISN/RPS classification and NIH indices have recently been revised by a series of retrospective validation studies to improve and minimize the controversial

**Keywords:** Systemic lupus erithematosus, lupus nephritis, renal biopsy, ISN/RPS classification, NIH activity and chronicity indices, patients management, prognosis

Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disease that frequently involve kidneys in women. The development of the disease is related to exposure to environmental factors in individuals with genetic predisposition. It is characterized by loss of tolerance against nuclear autoantigens, lymphoproliferation, polyclonal autoantibody production, immune complex disease and multiorgan tissue inflammation [1]. The affected organs include skin, joints, heart, lungs, kidneys, central nervous system and serous membranes. The disease involves a sequence of manifestations such as arthritis, serositis, chronic fatigue, skin rashes, glomerulonephritis, neurological involvement and hematological abnormalities [2]. SLE is the most frequent cause of secondary glomerular disease [3–5]. Lupus nephritis (LN) as a disease usually develops early in the clinical course of SLE in up to 50% of patients. The development of effective diagnostic tests and the introduction of new therapies has shown an improvement in the survival of patients with SLE. However, SLE patients still have a higher risk of death than the general population, especially patients with LN. Lupus glomerulonephritis with intense activity requires greater immunosuppression with increased risk of death from opportunistic infections. On the other hand, long-term treatment with high-dose

Guiding the Clinician
