Introduction 

            Systemic lupus erythematosus is an autoimmune disease that can be caused by both genetic and environmental factors and can take a toll on nearly all organ systems. This autoimmune disease is most common among middle aged women. It can present very differently in each patient, which makes the diagnosis and treatment challenging. Chronic inflammation from systemic lupus erythematosus ultimately leads to multiple organ failure (1). I chose to research this condition because I work in the emergency department and often see patients come in due to a lupus flare up and would like to better understand the disease. 

Causation

            Systemic lupus erythematosus can be caused by genetic factors, environmental factors, or a combination of both. Three of the main causes of this autoimmune disease are the inability to clear apoptotic cells from the body, an increased response to cells that produce type I interferons, and increased ease of activation of autoreactive B cells producing autoantibodies. Overall systemic lupus erythematosus is caused by the failure of many different mechanisms that control cell death (1).

            Researchers are still determining which gene mutations cause the development of systemic lupus erythematosus. They have determined about fifty different points of mutation that could cause this autoimmune disease, and most of these affect the production of type I interferons. Currently, studies can only explain about fifteen percent of the heredity of systemic lupus erythematosus (1). 

            In addition to genetic factors, environmental factors also contribute to the development of systemic lupus erythematosus. The main factor that has been studied is exposure to ultraviolet radiation. In addition, viral infections have also been linked to the manifestation of this autoimmune disease. Specific viruses which enhance this disease process have not been disclosed. Researchers believe that this is due to the virus’s ability to activate the type I interferon pathway. Drug induced lupus can also occur mostly in hospital settings and has been observed in patients who have received chlorpromazine, hydralazine, isoniazid, and procainamide (1).

Signs & Symptoms

            The signs and symptoms caused by systemic lupus erythematosus widely varies from patient to patient due the ability of the disease to affect many different organ systems. Joint, skin, and kidney involvement are the most commonly reported among patients with systemic lupus erythematosus. Many patients experience joint pain, rashes, and an increased sensitivity to sunlight. In addition, diarrhea and abdominal pain is very common among these patients. Hair loss is also a very common sign of systemic lupus erythematosus (3).

Epidemiology

            Although systemic lupus erythematosus has been observed among patients of both sexes and all ages, the mean age of patients with this disease is thirty-five, most of which are females. The ratio of female to male patients with this autoimmune disease are about nine to one. Black, Hispanic, and Asian women are also more likely to have this disease and more severe symptoms when compared to white women (5). Depending on the study, in the United States, between two and seven individuals per one-hundred thousand people have systemic lupus erythematosus. The incidence depends on the criteria that researchers are using to define the autoimmune disease (2).

Diagnosis 

            Systemic lupus erythematosus is diagnosed by both clinical implications and laboratory tests. Clinical implications used for diagnosis are outlined by the revised American College of Rheumatology classification criteria for SLE. Some of the indication outlined in this chart include different types of rashes, pleuritis, renal disorders, neurological disorders, and many others due to the variability of this autoimmune disease. The laboratory tests used are those used to diagnose the organ system disorders that may be a comorbidity of systemic lupus erythematosus. The diagnosis of this autoimmune disease is very difficult due to the high level of variability (2).

Treatment 

            Due to the high level of variability among patients with systemic lupus erythematosus, the treatments vary greatly. For patients with very mild symptoms, they are simply told to avoid over-exposure to sunlight and topical ointments to control rashes. Patients with moderate to severe cases of this autoimmune disease are treated with glucocorticoids to begin as well as immunosuppressive therapy used long term. Patients are typically tapered off of glucocorticoids after a certain period of time depending on their condition. No cure has been discovered yet for this disease, but the treatments that are currently used treat the symptoms and some of the comorbidities involved with the disease (2).

Current Research 

            Recently, many different monoclonal antibodies are being tested as a treatment method for systemic lupus erythematosus. One of the most recent tests included the use of anifrolumab which is an antibody to subunit one of the type I interferon. Patients received a three hundred milligram dose every four weeks for forty-eight weeks. About half of the patients in this study had an improvement of symptoms. This is just one of the many monoclonal antibody treatments being tested. Anifrolumab is now in human clinical trials, but other monoclonal antibodies are still being tested in mice (4).

References

  1. Bengtsson, A. A. & Ronnblom, L. (2017). Systemic lupus erythematosus: Still a challenge for physicians. Journal of Internal Medicine, 281(1). 52-64. https://doi-org.proxy.lib.odu.edu/10.1111/joim.12529
  2. Kaul, A. et al. (2016). Systemic lupus erythematosus (Primer). Nature Reviews: Disease Primers, 2(1). 1-21. DOI:10.1038/nrdp.2016.39
  3. Leuchten, N. et al. (2016) THU0349 Early symptoms of systemic lupus erythematosus (SLE) recalled by 337 SLE patients. Annals of the Rheumatic Diseases, 75. 313. https://doi.org/10.1136/annrheumdis-2016-eular.3561
  4. Morand, E. F. et al. (2020). Trial of anifrolumab in active systemic lupus erythematosus. The New England Journal of Medicine, 382(3). 211-221. https://doi.org/10.1056/NEJMoa1912196
  5. Nusbaum, J. S. et al. (2020). Sex differences in systemic lupus erythematosus: Epidemiology, clinical considerations, and disease pathogenesis. Mayo Clinic Proceedings, 95(2). 384-394. https://doi.org/10.1016/j.mayocp.2019.09.012