Dr. Joan T. Merrill is a professor of medicine at the University of Oklahoma who presented on lupus at the 2020 Congress of Clinical Rheumatology – East. She spoke about how characteristics like race and gender can impact how lupus presents itself, according to an article in Healio.
Lupus, also known as systemic lupus erythematosus, is an autoimmune disease in which the immune system attacks the body’s own tissue. Lupus causes inflammation, pain, and in severe cases, tissue damage to the joints, kidney, skin heart, lungs, and brain. People who have lupus can experience flare-ups, in which the symptoms are at their worst, and periods of remission, where they have little to no pain. Every case is different, and people experience various levels of severity. Lupus also disproportionately affects females and people of African American, Asian, and American Indian descent. It is also an invisible illness, meaning that there are no external factors that are noticeable to others. Because of this, many people go without a diagnosis. In fact, an average of six years passes between the onset of symptoms and the medical diagnosis for lupus, according to The Lupus Foundation of America. While there is no cure for lupus, treatment does exist. It is a lifelong process, and it can help to reduce flare-ups and pain.
Lupus patients also need to be aware that their condition can progress into lupus nephritis, which is a common complication. In this condition, antibodies attack the part of the kidneys that filter out waste, causing proteinuria, inflammation, hematuria, high blood pressure, and kidney failure in extreme cases. Females and those of African and Asian descent are at a higher risk of developing lupus.
Symptoms specific to lupus nephritis include pain and swelling in the joints, dark and foamy urine, edema, high blood pressure, muscle pain, fever, and rash. The cause is unknown, although medical professionals suspect that it is a combination of genetic and environmental factors. Various lab tests, including urine tests, blood tests, and a kidney biopsy, are used to diagnose this condition. Treatment aims to decrease inflammation, reduce high blood pressure, and suppress the immune system.
Gender’s Impact on Lupus
Nine out of ten lupus patients are female. This statistic pushed Dr. Merrill to look into why. One of the reasons she found was B cells, which are triggered more in females than they are males. Female hormones can also affect the regulation of these B cells.
This is not to say that males are not affected by lupus. In fact, they are more likely to have a severe case. Merrill stresses the importance of seeking treatment, especially as males may experience serious symptoms.
Race’s Impact on Lupus
African Americans are the most likely to develop lupus, and Native Americans have a slightly higher chance than the general population. However, people of Asian descent do not have this predisposition.
Merrill notes that it is important to remember that incidence does not translate to severity. Just because African Americans are the most likely to develop the disease, that does not mean they are the most likely to develop complications and experience a severe case. In fact, those of Chinese descent are the most likely to see their lupus progress into lupus nephritis.
Lupus at the Cellular Level
Dr. Merrill describes the “circular process” of certain cells, plasmacytoid dendritic cells, and type 1 IFN signalling work around the B cells. Other cells are involved, such as myeloid cells, and they are all playing a role in the production of cytokines. Cytokines then cause inflammation, which is difficult to stop after it has already started.
This process occurs in everyone that has lupus, but it can affect different individuals in different ways. Genetics can impact lupus, making it impossible to predict how people will react to the disease. Merrill stresses the importance of more research into this process. Maybe if it is fully understood, it will lead to better treatments.