Systemic lupus erythematosus

Systemic lupus erythematosus (SLE), or just called lupus, is a complex autoimmune disease characterized by the production of several types of antibodies.

Lupus is a systemic or multi-organ disease that means that can affect almost any tissue or organ system.

Systemic lupus erythematosus (SLE) is a chronic disease of exacerbations and remissions with variable course and prognosis.

Lupus has a broad spectrum of clinical manifestations and may resemble different diseases over the time in the same patient.

Lupus can cause skin rash, arthritis, anemia, seizures, psychosis and it can affect also internal organs including the kidneys, lungs and heart.

Lupus has an estimated prevalence of about 300-400 per 100,000 persons, but it may be different depending on the ethnic/racial group. In blacks, lupus is more common.

Ninety percent (90%) of lupus patients are women of childbearing age between the ages of 14 and 45. However, the disease can occur at any age.

Lupus is a disorder of the immune system. The immune system protects the body against cancer and infections.

In individuals with lupus, the immune system becomes overactive and the body produces a big amount of antibodies that attack the body's own cells.

The exact etiology and pathogenesis of lupus remain unknown, but the following factors play an important role:

• Genetic factors.
• Environmental factors (tobacco, exposure to UV light, infections, etc.).
• Hormonal factors: Sex hormones such as estradiol, testosterone, progesterone, prolactin, and dehydroepiandrosterone (DHEA) can modulate the incidence and severity of the disease.

Lupus can be classified into:

• Systemic lupus erythematosus: It is the most common type. It can affect almost any organ system in outbreaks.
• Cutaneous or discoid lupus: Mainly affects the skin.
• Drug-Induced lupus: Hydralazine, procainamide, isoniazid, minocycline and sulfasalazine have all been implicated in causing lupus. It disappears after discontinuation of the offending drug.
• Neonatal lupus erythematosus: It is rare. It is due to fetal exposure to maternal autoantibodies transported across the human placenta.

Lupus has a variable course and severity ranging from skin and joint involvement to organ-threatening and life-threatening disease.

The main symptoms of systemic lupus erythematosus (SLE) are:

• Malar butterfly rash: Non-scarring rash over cheeks and bridge of nose.
• Skin rash or discoid rash, seen as erythematous raised patches on the skin, as a result of unusual reaction to sunlight.
• Oral or nasopharyngeal ulcers.
• Arthritis in one or more joints.
• Kidney inflammation (lupus nephritis).
• Neurological symptoms: Seizures, acute confusional states, psychosis or an increased risk of cardiovascular events.
• Others: Fatigue, fever, weight loss, non-scarring alopecia, painful red or purplish sores usually on fingers or feet, chest pain when breathing deeply and abdominal pain.

Many symptoms are not specific to just lupus, and it is therefore important to make a proper distinction between lupus and other diseases. It requires some insight from the physician.

The diagnosis of systemic lupus erythematosus is usually based on clinical and laboratory criteria. It is common to find the following alterations:

• A low white blood cell (WBC) count called leukopenia.
• A low red blood cell (WBC) count called anemia.
• A low platelet count called thrombocytopenia.
• Abnormal urinalysis with a possible high presence of white blood cells, proteins or urine casts (especially red blood cell casts).
• Deficiencies of complement proteins. The complement system is part of the immune system and plays a crucial role in the innate defense against common pathogens.
• A broad spectrum of autoantibodies can be found in SLE patients. Presence of antinuclear antibody (ANA) is the most sensitive diagnostic criteria for SLE, as it is observed in virtually all patients with the disease (more than 98% of patients). They are not usually found in healthy individuals.

Sometimes the diagnosis is delayed, because the disease can evolve gradually, and it may resemble other diseases.

The treatment of lupus depends on the symptoms and the clinical course of the disease.

An early and accurate diagnosis, a better knowledge of the disease and the different therapeutic trials have contributed to improve the treatment of lupus.

There is no clear and generally accepted treatment strategy for lupus so periodical checkups and analytical tests are very important to treat the lupus manifestations as they occur.

As with all chronic diseases, the treatment of systemic lupus erythematosus (SLE) must be a balanced consideration of multiple disease-related and patient-specific aspects.

The most common drugs used to treat lupus are:

• Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for non-specific pain and the inflammatory manifestations (arthritis and myalgia).
• Systemic corticosteroids (glucocorticoids), as a result of their potent anti-inflammatory effects, are extensively used to treat lupus under medical surveillance.
• Antimalarial medication such as chloroquine and hydroxychloroquine are effective treatments against various cutaneous lupus manifestations.
• Several conventional immunosuppressive medications, such as cyclophosphamide or azathioprine, are reserved for more serious cases, including renal involvement.

Lupus has a remitting-relapsing course characterized by flares and periods of remission, chronically active disease, and long quiescence where the medication may be reduced or even discontinued.

Rheumatologists and internists are the recommended specialists to treat it because it may affect multiple organs, including the kidneys, lungs and heart.

Drug-Induced lupus has a better prognosis because it usually improves as soon as the responsible drug is discontinued.