What is lupus SLE? Your questions answered
What is lupus SLE? Are there different kinds of lupus?
Lupus SLE (systemic lupus erthythomatosus) is a chronic inflammatory autoimmune disease. Lupus is a complicated illness and there are several categories of lupus to consider, like drug induced lupus and discoid lupus.
I was recently diagnosed with lupus. This post is about giving you general information, but you can read about my diagnosis feelings here. This is a long post, so I've split everything into sections so you can jump around to where the information will be most useful to you. I've also linked some meta-analysis studies, systematic reviews and lots of resources to support you.
Standard disclaimers apply: this is a blog containing general information, speak to your doctor before changing / starting / stopping supplements or activities that influence your health.
Table of Contents
What are autoimmune diseases? What types of lupus are there?
What are autoimmune diseases? What types of lupus are there?
Autoimmune disease occurs when an overactive immune system mistakenly destroys your own healthy tissues. Your body makes antibodies (immune response soldiers) to itself and attacks those healthy tissues, resulting in inflammation.
It almost sounds kind of benign when we put it like that, but autoimmune diseases are serious and can have significant complications. 3 out of 5 deaths worldwide occur from diseases related to inflammation.
Systemic lupus erythematosus is a chronic disease - it's lifelong. There's a genetic component to this disorder. If you have lupus, other family members may also have a history of immune system disorders resulting in increased risk.
Lupus can be active, or in remission. If the disease is active, it's referred to as a lupus flare. Lupus flares occur for a variety of reasons, stress, UV exposure, toxins from cigarette smoke, medications, and some food triggers. We'll discuss these in depth.
There are different kinds of lupus, although when active they are all causing a similar disease process in your body. Systemic lupus means lupus throughout your system, basically. It's taking liberties with all of your body. This is the most serious form, and the most common.
You can also have discoid lupus, which affects the skin more so than internal organs. Lupus can also be triggered by certain medications and we refer to this as drug-induced lupus.
Drug-induced lupus usually goes away after you stop taking the drug that caused it, although it's not easy, or at times possible, to determine what the trigger was for a lupus flare.
Lupus is a complex condition, we don't fully understand it. We don't really know why some patients have a higher risk of developing lupus, or a lupus-like syndrome.
Systemic Lupus Erythematosus (SLE)
For those who like a little bit more clinical depth to their explanations, I'll provide some medical jargon here. If this is a bit too much information, feel free to skip straight to the symptoms of lupus section.
So why is your immune system attacking itself? Antibodies are part of your immune system, they're produced by B cells, a specialised type of white blood cell.
Antibodies are proteins and they are released in response to B cells detecting foreign invaders (antigens); like bacteria, viruses, moulds or parasites. You might see another term, immunoglobulin. This is another name for antibodies.
So, antibodies (or immunoglobulins) go forth to attack antigens (or invaders). Antibody = good guy, antigen = bad guy.
What goes wrong in the body?
To understand this, we'll need to quickly (very quickly, promise) revise the structure of a cell. If this is a bit too much information, feel free to skip straight to the symptoms of lupus section.
Your body is made of trillions of cells. These cells have an outer membrane, and inside that membrane, cells have a range of structures doing all of the metabolic, cellular things that cells do. Within this, you have a smaller membrane, called the nucleus. Inside the nucleus lies your DNA, the code telling the cell what it's supposed to be doing.
Why is this important? Usually, in a healthy functional body, the nucleus hides your DNA from your immune system. Your immune system isn't programmed to recognise your DNA, because your body hides it. Why bother with the extra work if they don't interact anyway?
As far as your immune system is concerned, your DNA is technically a foreign invader. But if the DNA is safely within the nucleus of a cell where it's supposed to be, everyone lives happily ever after.
When a cell dies of natural causes (this is called programmed cell death, or apoptosis), other cells called macrophages arrive and dispose of the cell remains before the immune system can catch a glimpse of your DNA.
It might be, that in lupus patients, this clearing away of dead cells is slow or impaired which allows your immune system to see your DNA as it leaks out of old nucleus membranes before the macrophages can get to it. This peer reviewed article explains the theory well if you're looking for more in-depth information.
The immune system doesn't recognise the DNA, gets scared and makes a pile of antibodies, which then go on to attack whatever they like. Your body is launching an attack on your own DNA, causing disease flares.
Self-tolerance is our body's ability to recognise and not attack itself. In autoimmune disease, this mechanism fails. Antibodies clump together with other proteins and form sticky little immune complexes, which then lodge in your tissues doing all sorts of damage.
Lupus nephritis is a common complication in lupus, immune complexes lodge in the kidneys, causing potentially irreversible damage. We'll talk more about complications later on.
Discoid Lupus Erythematosus (DLE)
Discoid lupus erythematosus (DLE) is a chronic skin condition that affects about 10% of people with lupus. The name 'discoid' refers to the coin-shaped lesions that appear on the skin. These lesions can be red, scaly, and itchy, and they can lead to scarring and permanent hair loss. Discoid lupus can also affect the mucous membranes of the mouth and nose.
Discoid lupus generally only affects the skin and does not typically affect internal organs. However, between 1% and 5% of people with discoid lupus may go on to develop systemic lupus erythematosus.
Drug-Induced Lupus (DILE)
Drug-induced lupus erythematosus (DILE) is a rare form of lupus that is caused by certain medications. Symptoms of DILE are similar to those of SLE and can include joint pain, fatigue, fever, and skin rashes. However, unlike SLE, DILE usually does not affect major organs such as the kidneys and heart.
Some of the medications that can cause DILE includes hydralazine, procainamide, and isoniazid. Some biologic drugs like infliximab and adalimumab can also cause a lupus-like syndrome (and is referred to as ATIL, anti-tumour necrosis factor induced lupus).
This type of lupus typically occurs in people who have been taking these medications for several months or years. Usually, DILE symptoms typically disappear once the drug that caused them has ceased.
What are the symptoms of lupus?
People with lupus can have a range of symptoms. Lupus flares can be mild or severe, and symptoms can mimic a range of diseases. Systemic lupus erythematosus symptoms include (but are not limited to):
Joint pain and stiffness, swollen joints
Skin rashes, including butterfly rash on the face (malar rash)
Photosensitivity (increased sensitivity to light)
Mouth ulcers or sores
Dry or inflamed eyes and
Swollen lymph nodes (glands)
Chest pain when breathing deeply (pleurisy)
Shortness of breath
Raynaud's phenomenon (fingers and toes turn blue or white in response to cold or stress)
Swollen feet or ankles
Digestive problems, including nausea and abdominal pain
Kidney damage (lupus nephritis)
Psychosis or other mental health problems
Increased risk of infection
Weight loss or gain
Blood disorders, blood clots
Abnormal menstrual cycles
Peripheral neuropathy (numbness, tingling or burning sensations in the hands and feet)
You can see why lupus is considered tricky to diagnose, patients may present with many of these symptoms, or they might just feel a bit flat or generally unwell with muscle aches or pains. The immune regulation dysfunction that occurs in lupus varies significantly from person to person. Lupus might look like rheumatoid arthritis, or it might look like being a bit run down.
Some of the more serious lupus complications, like kidney damage (lupus nephritis) or cardiovascular disease (coronary artery disease, or atherosclerosis), can be life-threatening. Some patients will end up needing a kidney transplant.
High blood pressure can be a sensitive indicator of kidney disease and you should keep an eye on this, alongside any other health concerns. High blood pressure also negatively affects cardiovascular system function, and women are at particular risk of developing coronary artery disease. Lupus complications can compound because it causes disease activity in so many systems at once.
Biologics/Monoclonal Antibodies: Monoclonal antibody (mAb) therapy is a newer form of treatment for systemic lupus erythematosus. Monoclonal antibodies are laboratory-produced molecules that mimic the immune system's ability to recognise and attack invaders (antigens).
There are currently several monoclonal antibody therapies approved for use in the treatment of lupus and they either target B cells directly, or a specific protein involved in the production of antibodies. Blocking these pathways can help to reduce lupus activity and the associated symptoms.
Monoclonal antibody therapy can be used alone or in combination with other lupus medications, such as corticosteroids or immunosuppressants.
NSAIDs: One of the most commonly used medication types for lupus is non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin or ibuprofen. They can help to relieve joint pain and inflammation, as well as other symptoms like fever and headaches.
Corticosteroids: such as prednisolone, are also commonly used in the treatment of lupus. They work by suppressing the immune response, which reduces inflammation and prevents damage to organs such as the kidneys and lungs. Corticosteroids can have significant side effects, such as weight gain, increased risk of infections, and bone loss - especially if used long-term. Outcomes tend to be worse in patients who use long-term steroid treatments.
Immunosuppressive drugs: such as methotrexate, azathioprine, and mycophenolate are another class of medications commonly used. These older generation immunosuppressants can be particularly useful in treating organ damage caused by lupus, such as kidney damage, but are reasonably toxic and can have some nasty side effects.
Other medications that may be used in the treatment of lupus include antimalarials, also known as DMARDs (disease modifying anti-rheumatic drugs) such as hydroxychloroquine. They can help to reduce inflammation and prevent flares and are generally protective, they improve outcomes for patients who take it.
Lupus patients will often take lots of other medications that target specific symptoms; like antihistamines for itchiness and skin rashes or pain relief for inflamed joints.
So what have we learned? Lupus is a complex chronic autoimmune condition. There are several types of lupus, from systemic, to discoid, to drug-induced. It's difficult to diagnose, and symptoms can vary significantly person to person.