Kyle A. Habet, M.D.
Lupus In a Nutshell
Systemic Lupus Erythematosus (SLE, or just Lupus in short) is an autoimmune disease.1 This means the body forms antibodies against itself. Normally an antibody attaches itself to foreign invaders like bacteria and viruses and tells the immune system to kill it.2 It’s the body’s way of tagging unwelcome visitors. Think of a laser-guided missile. The laser is the antibody and the missiles are the immune system.
In rheumatoid arthritis, this laser is pointed at the joints, in Ulcerative Colitis the laser is pointed at the gut and in Type 1 Diabetes, the laser is pointed at the insulin-producing cells in the pancreas.3,4,5 Lupus is a little different. Instead of a laser, lupus is more like a disco ball, signaling the missiles to target many different tissues. One light might tell the immune system to attack blood vessels, another may signal that the neurons in the brain are invaders. This is why Lupus is so devastating and has an extremely wide array of clinical manifestations.
Sometimes the antibodies flank an invader all at once and form an immune complex. This is just a large molecule made up of a cluster of antibodies. These can be problematic because they can lodge in certain places in the body like the capillaries of the skin and kidneys. Immune complexes activate mediators of inflammation and cause swelling and additional damage to the region.6 The kidneys are particularly susceptible to damage from immune complexes and is one of the major causes of death in Lupus patients.7
What Are The Symptoms?
A mnemonic I found useful for learning the symptoms of lupus is: RASH OR PAIN
R: Rash: Lupus patients have a characteristic rash on the face (see Fig. 1). Lupus patients are very susceptible to the sun.8
A: Arthritis: The disco lasers might point at the joints or the immune complexes may deposit in the small joints of the hands and cause inflammation.6
S: Serositis: Inflammation of the lining of some organs like the heart (pericarditis) or lungs (pleuritis)
H: Hematologic abnormalities: Platelets and white or red blood cells might get targeted by the lasers. I think you get the idea by now, right?
The rest of the mnemonic is as follows and can all be explained by the laser and disco light concept:
Oral ulcers, Renal disease, Photosensitivity, Auto-antibodies detectable on lab tests, Immune disfunction, Neurologic disorders.
Who are most affected?
SLE is a chronic debilitating disease which mainly afflicts women, especially those of African-American, Asian, or Hispanic descent. 6 The female to male ratio for Lupus is 9:1. That’s right. 90% of Lupus patients are female. 9
So, what causes this?
Sadly…. We don’t know. Lupus is manageable, though. There are many medications to prolong the life expectancy of lupus patients and recent advancements have been made in 2018.10 Targeted therapies are being developed and hopefully effective, targeted therapies will result in a better quality of life for patients with this condition.11

Taken from: https://ars.els-cdn.com/content/image/1-s2.0-B9780444627025000032-f03-12-9780444627025.jpg
References
1. Pathogenesis of systemic lupus erythematosus. Accessed May 9, 2020. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1769989/
2. Forthal DN. Functions of Antibodies. Microbiol Spectr. 2014;2(4):1-17.
3. DiMeglio LA, Evans-Molina C, Oram RA. Type 1 diabetes. Lancet Lond Engl. 2018;391(10138):2449-2462. doi:10.1016/S0140-6736(18)31320-5
4. Guo Q, Wang Y, Xu D, Nossent J, Pavlos NJ, Xu J. Rheumatoid arthritis: pathological mechanisms and modern pharmacologic therapies. Bone Res. 2018;6. doi:10.1038/s41413-018-0016-9
5. Ungaro R, Mehandru S, Allen PB, Peyrin-Biroulet L, Colombel J-F. Ulcerative colitis. Lancet Lond Engl. 2017;389(10080):1756-1770. doi:10.1016/S0140-6736(16)32126-2
6. Systemic Lupus Erythematosus | NEJM. Accessed May 9, 2020. https://www.nejm.org/doi/full/10.1056/NEJMra1100359?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3dpubmed
7. Jaryal A, Vikrant S. Current status of lupus nephritis. Indian J Med Res. 2017;145(2):167-178. doi:10.4103/ijmr.IJMR_163_16
8. Norris DA. Pathomechanisms of photosensitive lupus erythematosus. J Invest Dermatol. 1993;100(1):58S-68S. doi:10.1111/1523-1747.ep12355599
9. Moulton VR, Tsokos GC. Why do women get lupus? Clin Immunol. 2012;144(1):53-56. doi:10.1016/j.clim.2012.04.003
10. Sciascia S, Radin M, Roccatello D, Sanna G, Bertolaccini ML. Recent advances in the management of systemic lupus erythematosus. F1000Research. 2018;7. doi:10.12688/f1000research.13941.1
11. Vukelic M, Li Y, Kyttaris VC. Novel Treatments in Lupus. Front Immunol. 2018;9. doi:10.3389/fimmu.2018.02658