The Link Between Nephritis and Lupus

Recently, the story of a kidney transplant to singer and actress Selena Gomez made headlines in numerous newspapers and leading websites. Selena’s story of living with lupus has helped to raise awareness about the disease. In 2015, she revealed she was suffering from lupus, and within two years, everyone learned about her kidney failure. Her story not only raised awareness about lupus, but also demonstrated how life-threatening it can be and how little progress has been made in finding a treatment for the condition. Her story created fear towards the disease and forced the scientific community to pay more attention to this long-neglected medical condition (1).

Because lupus is an autoimmune disease, it is difficult to treat. It is also a multi-organ disease. In lupus, a person’s immune system fails to recognize its own body tissues and attacks them, which causes various manifestations of the disease. Further, it is related to gender and family history: lupus mostly occurs in childbearing women, but it can even occur in teenagers. 

Kidney issues are quite common in lupus. 90% of people with lupus will also have kidney disease. Even if lupus is diagnosed at an early age, kidney disease can still occur; it is not uncommon to have renal problems if lupus occurs at a young age. The kidneys are very important in excreting metabolic wastes and maintaining fluid balance. The fluids and toxic waste may accumulate if the kidneys fail to function. End-stage kidney disease may cause glomerulonephritis, and one of the most common causes of glomerulonephritis, it is slowly emerging, is lupus.

End-stage renal disease should be diagnosed as early as possible, as it is life-threatening. However, since most of the functional cells are not damaged, symptoms of kidney disease do not appear, making it very difficult to diagnose kidney disease in its early stage. There is no reliable way to diagnose the problem because the symptoms usually occur only after 90% of the kidney has been damaged. Only a laboratory diagnosis can diagnose kidney disease at an early stage, however, this is also a challenge.

Part of the kidney is damaged in lupus due to two mechanisms of the disease: extrarenal and intrarenal.

• Extrarenal: Extrarenal damage occurs due to the deposition of circulating immune complexes. These immune complexes are formed when various organs are damaged by lupus. They are then deposited in the kidneys during the blood filtration process. This causes inflammatory disease of the kidneys and damages the local filtering structures.
• Intrarenal: Kidney cells are attacked directly by the antibodies. The local inflammatory response further worsens the condition.

The kidneys may not only be damaged due to lupus, but also because of certain toxic effects of medications. Due to poor functioning of the local immune system, there is a higher chance of getting urinary tract infections in people with lupus. This can also occur if the person takes immunosuppressant drugs, and various structures of the kidney may get damaged due to anti-inflammatory drugs as well.

Kidney function needs to be closely monitored in all lupus cases. Some of the symptoms include swelling in the feet, legs, hands, ankles, and face due to fluid retention. It may also cause high blood pressure. The symptoms depend on how many kidney cells are damaged, and this can only be assessed with the help of laboratory tests. These include urine and blood tests. Another procedure is a kidney biopsy, which can accurately determine kidney disease. If a lupus patient needs dialysis, it does not mean they have end-stage renal disease. Research has shown that if the right treatment is given, many people can recover and may not need to continue with dialysis.