Histologically a wire-loop lesion will be present. The wire loop lesion is a glomerular capillary loop with subendothelial immune complex deposition that is circumferential around the loop.
Furthermore, patients may suffer from other symptoms of lupus unrelated to kidney function. Such symptoms can include arthritis, fevers, gastro-intestinal disturbances, headaches, fatigue, and fluid in the joints.
The diagnosis of lupus nephritis depends on blood tests, urinalysis, X-rays, ultrasound scans of the kidneys, and a kidney biopsy.
The World Health Organization has divided lupus nephritis into five classes based on the biopsy.
* Class I is minimal mesangial glomerulonephritis which is histologically normal on light microscopy but with mesangial deposits on electron microscopy.
* Class II is based on a finding of mesangial proliferative lupus nephritis. This form typically responds completely to treatment with corticosteroids.
* Class III is focal proliferative nephritis and often successfully responds to treatment with high doses of corticosteroids.
* Class IV is diffuse proliferative nephritis. This form is mainly treated with corticosteroids and immunosuppressant drugs.
* Class V is membranous nephritis and is characterized by extreme edema and protein loss.
The medical therapy for lupus nephritis depends on the severity of the disease. For mild disease, corticosteroids are, in general, prescribed. More severe disease requires treatment with immunosuppressant agents. The two most commonly-used agents are mycophenolate mofetil and intravenous cyclophosphamide.