Волчаночный нефрит: причины, классификация и лечение.

Inflammation of the kidneys

The cause of lupus nephritis, a genetic predisposition, plays a significant role in lupus nephritis. Multiple genes, many of which are not yet identified, mediate this genetic predisposition. The immune system protects the human body from infection, and with immune system problems it cannot distinguish between harmful and healthy substances. Lupus nephritis affects approximately 3 out of 10,000 people.

The World Health Organization has divided lupus nephritis into five stages based on the biopsy. This classification was defined in 1982 and revised in 1995. Class IV disease (Diffuse proliferative nephritis) is both the most severe, and the most common subtype. Class VI (advanced sclerosing lupus nephritis) is a final class which is included by most practitioners. It is thought to be due to the chronic interferon exposure. +OrderNameIncidenceLight microscopyElectron microscopyClinical findings and other testsTreatmentClass IMinimal mesangial glomerulonephritis5%Normal appearanceMesangial deposits are visible under an electron microscopeKidney failure is very rare in this form. Class IIMesangial proliferative glomerulonephritis20%Mesangial hypercellularity and matrix expansion. Microscopic haematuria with or without proteinuria may be seen. Hypertension, nephrotic syndrome, and acute kidney injury are very rare at this stage. Global sclerosis involving more than 90% of glomeruli, and represents healing of prior inflammatory injury. Active glomerulonephritis is not usually present. This stage is characterised by slowly progressive kidney dysfunction, with relatively bland urine sediment. Response to immunotherapy is usually poor.

Drug regimens prescribed for lupus nephritis include mycophenolate mofetil (MMF), intravenous cyclophosphamide with corticosteroids, and the immune suppressant azathioprine with corticosteroids. MMF and cyclophosphamide with corticosteroids are equally effective in achieving remission of the disease, however the results of a recent systematic review found that immunosuppressive drugs were better than corticosteroids for renal outcomes. MMF is safer than cyclophosphamide with corticosteroids, with less chance of causing ovarian failure, immune problems or hair loss. It also works better than azathioprine with corticosteroids for maintenance therapy. A 2016 network meta analysis, which included 32 RCTs of lupus nephritis, demonstrated that tacrolimus and MMF followed by azathioprine maintenance were associated with a lower risk of serious infection when compared to other immunosuppressants or glucocorticoids. Individuals with lupus nephritis have a high risk for B cell lymphoma (which begins in the immune system cells). 10 30% of people with lupus nephritis progress to kidney failure requiring dialysis, with the 5 year mortality rate of lupus nephritis being 5 25%. The proliferative forms of lupus nephritis are associated with a higher risk of progression to end stage kidney disease. Black and Hispanic people with lupus nephritis are more likely to present with severe disease at initial presentation (with more proteinuria and more extensive histopathologic changes) and progress to end stage kidney disease. This is thought to be due to socioeconomic factors but auto antibodies strongly associated with lupus nephritis such as anti Sm, anti Ro and anti ribonucleoprotein are also more commonly seen in Black and Hispanic people. Men with SLE tend to have more aggressive forms of lupus nephritis as well with a higher risk of progression to end stage kidney disease and higher risk of concurrent cardiovascular disease.