A Closer Look at Lupus Nephritis

The immune system serves as the body's defense against foreign substances or microorganisms that enter the body. Under certain circumstances, however, the immune system may have difficulty recognizing and distinguishing invaders from human cells. Instead of combating foreign substances invading the human body, a weakened immune system might produce antibodies that assault the body's healthy cells, tissues, and organs. Autoimmune disease is the medical term for this disorder. Autoimmune disease is one of the global health problems with an unknown exact number of patients, but the number is projected to rise year after year. Data from the National Institute of Health in the United States (USA) reports that more than 20 million people in the US (or about 7 percent of the total population) have autoimmune diseases (https://www.gene.com/stories/autoimmune-disease- 101). Women suffer from certain autoimmune disorders at a higher rate than men, accounting for around 75% of all cases. Asians, African Americans, Hispanics, and Native Americans, for example, are thought to have a higher chance of getting autoimmune disorders than other races and ethnicities. Rheumatoid arthritis, psoriasis, Grave's disease, and lupus are among the more than 80 forms of autoimmune disorders that affect diverse organs in the human body.

SLE (Lupus) is an autoimmune disease that causes inflammation in various parts of the body, including the joints, skin, blood vessels, and organs, such as the kidneys. Every year, more than 16,000 new cases of Lupus are reported in the United States. Lupus primarily affects women (9 out of 10 lupus patients are female), with only about 10% of Lupus patients being male. (https://www.hopkinsmedicine.org/health/conditions-and-diseases/lupus). The most common time for lupus to strike is during the reproductive years. People with African or Asian background are also more likely to get lupus. African Americans and Asian Americans are two to three times as likely than Caucasians to have lupus. Lupus is expected to affect one out of every 250 African American women in the United States (https://www.niddk.nih.gov/health-information/kidney-disease/lupus-nephritis). The specific etiology of Lupus is unknown at this time. However, genetics, hormones, infection, environmental factors, and medicines are thought to play a role in the onset of the disease. (https://www.hopkinsmedicine.org/health/conditions-and- diseases/lupus).

Lupus nephritis is one of the lupus complications to be aware of because it has the opportunity to generate major health concerns. Lupus nephritis develops when lupus autoantibodies attack tissue structure of the kidneys, which are responsible for filtering and removing toxins from the body. This causes kidney inflammation, which can lead to blood and protein presence in the urine (which should not be present at all or in very little amounts under normal conditions), high blood pressure, impaired kidney function, or even kidney failure. (https://www.mayoclinic.org/diseases-conditions/lupus-nephritis/symptoms-causes/syc-20354335). In individuals with lupus, kidney disease affects up to 5 out of 10 patients. Meanwhile, eight out of ten children with lupus will develop kidney dysfunction. Lupus nephritis is more common in African Americans, Hispanic/Latin Americans, and Asian Americans than it is in Caucasians. Men are also more likely than women to develop lupus nephritis. The presence of blood and protein in the urine, foamy urination, increased blood pressure, swelling of the legs, feet, and limbs, and a rise in creatinine in the blood are all symptoms and signs of lupus nephritis. Other lupus symptoms, such as joint pain and swelling, muscular aches, fever, and red rashes on the skin, particularly on the face (butterfly rash/malar), can also be seen in persons with lupus nephritis. (https:/ /www.niddk.nih.gov/health-information/kidney-disease/lupus-nephritis).

Histopathologically, lupus nephritis can be divided into several categories or classes: Class I (minimal mesangial stage) is characterized by the presence of negative or minimal protein content in the urine, creatinine levels that are still within normal limits and minimal damage to the glomerular structure of the kidneys. In Class I, immune complex deposits are present which can be detected using immunofluorescence method. Class II (proliferative mesangial stage) is characterized by the presence of blood in the urine with or without protein content. At this stage, elevated blood pressure and impaired renal function remain rare. In Class II there is mesangial hypercellularity and mesangial matrix expansion with deposition of immune complexes that can be detected by light microscopy. Class III (focal lupus nephritis) is characterized by the presence of blood and protein in the urine, increased blood pressure (hypertension), decreased renal function (eGFR) with or without nephrotic syndrome. Class IV (diffuse lupus nephritis) is the most common form and is characterized by the presence of all the signs of Class III plus low C3 complement and high hsDNA. Class V (membranous nephropathy) is characterized by the presence of the nephrotic syndrome and symptoms of the lower classes. Finally, Class VI (advanced lupus sclerosis) is characterized by slow but progressive renal failure with the presence of protein and sediment in the urine (Inderjeeth et al, MedicineToday, 2018; Pinheiro et al, Braz. J. Nephrol, 2019).


Blood, urine, and kidney biopsy can all be used to diagnose lupus nephritis. The GFR value can be calculated using blood tests to assess kidney function. Blood and protein levels in the urine can be determined through a urine examination. A kidney biopsy involves the removal of a limited sample of kidney tissue for examination under a microscope. This biopsy is the gold standard for confirming a diagnosis of lupus nephritis, as well as determining the disease's class/stage and determining treatment options. Until now, lupus treatment has focused on reducing kidney inflammation, lowering immune system activity, and blocking immune cells from attacking kidney tissues. Immunosuppressants such as cyclophosphamide, mycophenolate mofetil, and hydroxychloroquine, as well as anti-inflammatory medications like corticosteroids, can be employed. Blood pressure reducing medicines may be recommended in condition of lupus nephritis with increased blood pressure. Up to the moment, 10 to 30% of patients with lupus nephritis still have to experience kidney failure due to the permanent formation of scar tissue in the kidneys (https://www.niddk.nih.gov/health-information/kidney-disease/lupus- nephritis). It is therefore important to remember that early detection of lupus nephritis, combined with appropriate treatment, can help control the disease and prevent complications like kidney failure, hemodialysis (dialysis), kidney transplantation, and even death. Lupus nephritis is a concern, and protecting our kidneys from the potential of chronic renal failure is essential.

Djoko Santoso
Professor, Faculty of Medicine, Universitas Airlangga
Chairman of Health Department,
Indonesian Council of Ulama, East Java

Image source: mediciana

Translated from:
Mengenal lebih dekat Lupus Nefritis
by Djoko Santoso