Systemic Lupus Erythematosus

Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a remarkable and challenging disorder. Its diversity of clinical features is matched by the complexity of the factors (genetic, hormonal, and environmental) that cause it, and the array of autoantibodies with which it is associated. SLE is said to be an autoimmune disease is an autoimmune disease in which the body’s immune system mistakenly attacks healthy tissue. It is also said that an autoimmune disease occurs when the immune system attacks its own body because it confuses it for something foreign. It can affect the skin, joints, kidneys, brain, and other organs. SLE is much more common in women than men. It may occur at any age, but appears most often in people between the ages of 10 and 50. African Americans and Asians are affected more often than people from other races.

Causes
The exact cause of SLE is not known, but several factors have been associated with the disease. The disease is not linked to a certain gene, but people with lupus often have family members with other autoimmune conditions. The immune system is a complex system within the body that is designed to fight infectious agents, such as bacteria and other foreign microbes. One of the ways that the immune system fights infections is by producing antibodies that bind to the microbes. People with lupus produce abnormal antibodies in their blood that target tissues within their own body rather than foreign infectious agents. These confused antibodies are referred to as autoantibodie.

Because the antibodies and accompanying cells of inflammation can affect tissues anywhere in the body, lupus has the potential to affect a variety of areas. Sometimes lupus can cause disease of the skin, heart, lungs, kidneys, joints, and/or nervous system. When only the skin is involved by rash, the condition is called lupus dermatitis or cutaneous lupus erythematosus. A form of lupus dermatitis that can be isolated to the skin, without internal disease, is called discoid lupus. When internal organs are involved, the condition is referred to as SLE.

Genetic factors may increase the tendency of developing autoimmune diseases, and autoimmune diseases such as lupus, rheumatoid arthritis, and autoimmune thyroid disorders are more common among relatives of people with lupus than the general population. Moreover, it is possible to have more than one autoimmune disease in the same individual. Therefore, “overlap” syndromes of lupus and rheumatoid arthritis, or lupus and scleroderma, etc., can occur. Some scientists believe that the immune system in lupus is more easily stimulated by external factors like viruses or ultraviolet light. Sometimes, symptoms of lupus can be precipitated or aggravated by only a brief period of sun exposure.

There may be environmental triggers like ultraviolet rays, certain medications, a virus, physical or emotional stress, and trauma. SLE affects more women than men. Women also experience worsening of symptoms during pregnancy and with their menstrual periods. Both of these observations have led some medical professionals to believe that the female hormone estrogen may play a role in causing SLE. However, more research is still needed to prove this theory.

Signs and symptoms
People with SLE can develop different combinations of symptoms and organ involvement. Common complaints and symptoms include fatigue, low-grade fever, loss of appetite, muscle aches, hair loss (alopecia), arthritis, ulcers of the mouth and nose, facial rash (“butterfly rash”), unusual sensitivity to sunlight (photosensitivity), inflammation of the lining that surrounds the lungs (pleuritis) and the heart (pericarditis), and poor circulation to the fingers and toes with cold exposure (Raynaud’s phenomenon). Complications of organ involvement can lead to further symptoms that depend on the organ affected and severity of the disease. In childhood-onset SLE, there are several clinical symptoms more commonly found than in adults, including malar rash, ulcers/mucocutaneous involvement, renal involvement, proteinuria, urinary cellular casts, seizures, thrombocytopenia, hemolytic anemia, fever, and lymphadenopathy.

The classic presentation of a triad of fever, joint pain, and rash in a woman of childbearing age should prompt investigation into the diagnosis of SLE. Patients may present with any of the following manifestations:

  • Constitutional (eg, fatigue, fever, arthralgia, weight changes)
  • Musculoskeletal (eg, arthralgia, arthropathy, myalgia, frank arthritis, avascular necrosis)
  • Dermatologic (eg, malar rash, photosensitivity, discoid lupus)
  • Renal (eg, acute or chronic renal failure, acute nephritic disease)
  • Neuropsychiatric (eg, seizure, psychosis)
  • Pulmonary (eg, pleurisy, pleural effusion, pneumonitis, pulmonary hypertension, interstitial lung disease)
  • Gastrointestinal (eg , nausea, dyspepsia, abdominal pain)
  • Cardiac(eg,pericarditis, myocarditis)
  • Hematologic (eg, cytopenias such as leukopenia, lymphopenia, anemia, or thrombocytopenia)

In patients with suggestive clinical findings, a family history of autoimmune disease should raise further suspicion of SLE.
Diagnostic
The diagnosis of SLE is based on a combination of clinical findings and laboratory evidence. Familiarity with the diagnostic criteria helps clinicians to recognize SLE and to sub-classify this complex disease based on the pattern of target-organ manifestations.

SLE diagnostic criteria
Since individuals with SLE can have a wide variety of symptoms and different combinations of organ involvement, no single test establishes the diagnosis of systemic lupus

The following are 11 criteria used for diagnosing SLE:

    1. Malar (over the cheeks of the face) “butterfly” rash
    2. Discoid skin rash (patchy redness with hyperpigmentation and hypopigmentation that can cause scarring)
    3. Photosensitivity (skin rash in reaction to sunlight [ultraviolet light] exposure)
    4. Mucous membrane ulcers(spontaneous sores or ulcers of the lining of the mouth, nose, or throat)
    5. Arthritis (two or more swollen, tender joints of the extremities)
    6. Pleuritis or pericarditis (inflammation of the lining tissue around the heart or lungs, usually associated with chest pain upon breathing or changes of body position)
    7. Kidney abnormalities (abnormal amounts of urine protein or clumps of cellular elements called casts detectable with a urinalysis) Note: Ultimately, in patients with kidney disease from systemic lupus erythematosus (lupus nephritis), a kidney biopsy may be necessary to both define the cause of the kidney disease as being lupus-related as well as to determine the stage of the kidney disease in order to optimally guide treatments. Kidney biopsies are often performed by fine-needle aspiration of the kidney under radiology guidance, but in certain circumstances, a kidney biopsy can be done during an open abdominal operation.
    8. Brain irritation (manifested by seizures [convulsions] and/or psychosis, referred to as “lupus cerebritis”)
    9. Blood-count abnormalities: low white blood count (WBC) or red blood count (RBC), or platelet count on routine complete blood count testing
    10. Immunologic disorder (abnormal immune tests include anti-DNA or anti-Sm [Smith] antibodies, falsely positive blood test for syphilis, anticardiolipin antibodies, lupus anticoagulant, or positive LE prep test)
    11. Antinuclear antibody (positive ANA antibody testing [antinuclear antibodies in the blood])

Testing
The following are useful standard laboratory studies when SLE is suspected:

  • CBC with differential
  • Serum creatinine
  • Urinalysis with microscopy

Other laboratory tests that maybe used in the diagnosis of SLE are as follows:

  • ESR or CRP results
  • Complement levels
  • Liver function tests
  • Creatine kinase assay
  • Spot protein/spot creatinine ratio
  • Autoantibody tests

Treatment for SLE
Treatment for SLE is not curative— the goal is to ease the symptoms of lupus. Treatment can vary depending on how severe your symptoms are and which parts of your body are affected, treatment can vary. Dozens of medications have been reported to trigger SLE. However, more than 90% of cases of “drug-induced lupus” occurs as a side effect of one of the following six drugs: hydralazine (Apresoline) is used for high blood pressure; quinidine (Quinidine Gluconate, Quinidine Sulfate) and procainamide (Pronestyl; Procan-SR; Procanbid) are used for abnormal heart rhythms; phenytoin (Dilantin) is used for epilepsy; isoniazid (Nydrazid, Laniazid) is used for tuberculosis; and d-penicillamine (used for rheumatoid arthritis). These drugs are known to sometimes stimulate the immune system and cause SLE.

Fortunately, drug-induced SLE is infrequent (accounting for less than 5% of all people with SLE) and it usually resolves when the medications are discontinued. Treatments may include:

  • anti-inflammatory medications for joint pain and stiffness
  • steroid creams for rashes
  • corticosteroids of varying doses to minimize the immune response
  • antimalarial drugs for skin and joint problems

Nonsteroidal anti-inflammatory drugs (NSAIDs) are helpful in reducing inflammation and pain in muscles, joints, and other tissues. Examples of NSAIDs include aspirin, ibuprofen (Motrin), naproxen (Naprosyn), and sulindac (Clinoril). Since the individual response to NSAIDs varies, it is common for a doctor to try different NSAIDs to find the most effective one with the fewest side effects. The most common side effects are stomach upset, abdominal pain, ulcers, and even ulcer bleeding. NSAIDs are usually taken with food to reduce side effects. Sometimes, medications that prevent ulcers while taking NSAIDs, such as misoprostol (Cytotec), are given simultaneously.

Talk with your doctor about your diet and lifestyle habits. Your doctor might recommend eating or avoiding certain foods and minimizing stress to reduce the likelihood of triggering symptoms. You might need to have screenings for osteoporosis, since steroids can thin your bones. Preventative care such as immunizations and cardiac screenings may also be recommended