Systemic Lupus erythematosus (SLE) or simply, Lupus is a chronic inflammatory and autoimmune disease with a wide range of clinical presentations resulting from its effect on multiple organs and systems. Patients with SLE experience a loss of self tolerance. This is because of abnormal immunological function and the production of auto-antibodies; thus, leading to the formation of immune complexes that may have adverse effects on healthy tissues. Most patients also experience periodic flares of varying severity or instances in which no observable signs or symptoms are present.
Abnormal innate immune responses play significant role in the pathogenesis of SLE. They lead to tissue injury through the release of inflammatory cytokines and also to abnormal activation of auto-reactive T and B cells, with the later leading to pathogenic autoantibody production and resultant organ injury.
Due to its complex nature, SLE is sometimes known as the “disease of a thousand faces.”
TYPES OF LUPUS
There are four main types of Lupus; they are
- Neonatal and pediatric Lupus erythematosus (NLE)
- Discoid Lupus erythematosus (DLE)
- Drug-induced Lupus (DIL) and
- System Lupus erythematosus (SLE).
This form of Lupus is rare and is observed in newborns, which is believed to result from maternal auto-antibodies passing through the placenta. The common clinical presentations of neonatal lupus involve the heart, liver and skin.
Discoid Lupus Erythematosus (DLE)
DLE causes chronic skin sores with inflammation and persistent scaly, disc-like plaques on the scalp, face and ears. The cause of DLE is thought to be genetic with the highest prevalence in women, African-Americans, and persons between 20 and 40 years of age. It is diagnosed by biopsy of rash on the scalp, face, neck, or arms.
DLE does not affect the internal organs, but around 10% of people with DLE go on to develop SLE, according to the Lupus Foundation of America. However, it is possible that these people already had SLE and their skin symptoms led to a DLE diagnosis first.
This form of Lupus occurs after a patient has been exposed to a medication that causes autoimmune response. Most organs or systems may be affected, but upon discontinuation of the responsible medication, manifestations usually subside.
Systemic Lupus erythematosus
SLE is the most common types of SLE and is mostly referred to as Lupus. It is however differentiated from other types of Lupus by its multi-organ-system effects. Approximately 20-150 persons per 100,000 are diagnosed with SLE. It is seen mostly in females of child-bearing age. Nevertheless, it may affect both male and female of any age.
SLE can cause cause inflammations in the
Pathophysiology of SLE
SLE develops when a T-lymphocyte to an antigen-presenting cell (APC) is introduced. The T-cell receptor binds to the major histocompatibility complex (MHC) portion of the APC, and leads to cytokine release, inflammation and B-cell stimulation. Stimulation of B-cell division and the production of immunoglobulin G (IgG) auto-antibodies that can cause tissue damage also occur in SLE.
The antigens causing T-cell and B-cell stimulation in patients with SLE can be attributed to the inappropriate disposal of apoptotic cells. During the process of cellular death, pieces of cellular material form on the surface of the dying cell.
Nucleosomes and anionic phospholipids are examples of antigens that have been identified in patients with SLE, and
they have the potential to trigger an immune response. It is believed that the removal of these apoptotic cells is compromised because of the impaired functioning of phagocytic cells, resulting in suboptimal disposal of dying cells and antigen recognition in patients with SLE.
Management of SLE
The treatment of the signs and symptoms of lupus depends on the type of SLE and on the severity of the disease. However, general recommendations for all patients include protection from sun, exercises, proper diet and nutrition, and smoke cessation.
Nonsteroidal anti-inflammatory drugs (NSAIDs)
NSAIDs possess pain-reducing, anti-inflammatory and anticoagulation properties, which are beneficial in treating common SLE-associated manifestations. Potential side effects include gastrointestinal irritation and bleeding, renal toxicity, hepatic toxicity, and hypertension.
Mechanism of action of NSAIDs
NSAIDs function by inhibiting prostaglandin synthesis through the inhibition of cyclooxygenase enzymes, producing anti-inflammatory, analgesic and antipyretic effects.
Corticosteroids decrease the swelling and pain associated with inflammation, which occur in lupus flare. This treatment regimen however, has serious side effects which are:
- Cataracts and glaucoma
- Growth suppression
It is therefore advised that corticosteroids be used at the lowest possible dosage.
Mechanism of action of corticosteroid
Corticosteroids block cytokine activation and inhibit interleukins, ϒ-interferon and tumor necrosis factor-α.
The most used immunosuppressant are Cyclophosphamide and Azathioprine. They are used in severe cases where corticosteroid and antimalaria drugs fail to control the signs and symptoms of the disease.
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