Introduction:
Generally, our immune system protects us from infections and other diseases. However, in autoimmune disorders, the immune system attacks the healthy cells and tissues of the body. Therefore, it results in various signs and symptoms. One such autoimmune disorder is systemic lupus erythematosus (SLE). This article illustrates the rare manifestation of SLE, the bullous systemic lupus erythematosus.
What Is Bullous Systemic Lupus Erythematosus?
SLE causes inflammation and damages tissues of the skin, joints, brain, kidneys, lungs, and blood vessels. Bullous systemic lupus erythematosus is characterized by skin eruptions that occur during SLE. The most commonly affected sites include the face, neck, extremities, and trunk.
The other names for bullous systemic lupus erythematosus include:
-
Vesiculobullous SLE.
-
Bullous eruption of SLE.
What May Cause Bullous Systemic Lupus Erythematosus?
Bullous systemic lupus erythematosus may arise due to autoantibodies against the type VII collagen. Type VII collagen is responsible for binding the top (epidermis) and middle layer (dermis) of the skin. Thus, the antibodies produced against type VII collagen present in the dermo-epidermal junction result in the eruption of skin blisters.
The other factors that activate the formation of skin blisters in bullous systemic lupus erythematosus include:
-
Exposure to ultraviolet radiation.
-
Severe reactions to medications like Methimazole, Penicillamine, and Hydralazine.
Who Is at Risk for Bullous Systemic Lupus Erythematosus?
Bullous systemic lupus erythematosus may affect both males and females of all ages. However, it more commonly affects women between 20 to 40 years of age. Women of African origin also show a higher risk of developing bullous systemic lupus erythematosus. About one-third of individuals with SLE may present with bullous systemic lupus erythematosus.
What Are the Other Types of Lupus Erythematosus?
SLE is the most common type of lupus erythematosus. However, it also other kinds, as follows:
-
Drug-induced lupus erythematosus - Specific medications may trigger the development of lupus, but it revolves once the medicines are not used.
-
Cutaneous lupus erythematosus - It affects the skin and causes rashes and sensitivity to sunlight.
-
Neonatal lupus erythematosus occurs in newborns and is most likely transmitted from their mothers.
What Are the Clinical Manifestations of Bullous Systemic Lupus Erythematosus?
The various features of bullous systemic lupus erythematosus are as follows:
-
The skin may look erythematosus or normal.
-
Rigid fluid-filled blisters develop on the skin over the trunk, face, neck, upper limbs, and areas above the collar bone (clavicle).
-
The lesions may develop on the mucosa in the oral cavity.
-
Mild or absence of itchy skin.
-
The fluid-filled blisters appear clear or may contain blood.
-
Scarring does not occur when these blisters heal.
-
Lesions primarily develop over the sun-exposed area of the skin.
-
Elevated lesions with central white surrounded by erythematous areas are also observed.
-
Erythema gyratum - Concentric patterns of erythematous patches may rarely occur.
The other associated symptoms of systemic lupus erythematosus include:
-
Photosensitivity.
-
Weight loss.
-
Fatigue.
-
Inflammation and pain in joints.
How to Diagnose Bullous Systemic Lupus Erythematosus?
The main criteria to diagnose bullous SLE, put forward by Camisa and Sharma in 1983, include:
-
Fluid-filled blisters also develop in sun-exposed areas or can occur in other areas.
-
The presence of IgG or IgM antibodies at the basement membrane zone (BMZ) is between the epidermis and dermis; it is detected by a direct immunofluorescence test.
-
Positive or negative results in indirect immunofluorescence for autoantibodies against BMZ.
-
The microscopic (histopathology) examination of bullous SLE should resemble dermatitis herpetiformis.
-
The diagnosis of SLE should be confirmed based on the American College of Rheumatology (ACR) criteria.
What Is the Differential Diagnosis?
The conditions that look similar to bullous systemic lupus erythematosus are listed down:
-
Epidermolysis Bullosa Acquisita is also an autoimmune disorder that occurs as a result of autoantibodies against type VII collagen, similar to that of bullous SLE. It causes blisters that remain localized. The most common site includes the hands, elbows, feet, knees, and buttocks. The primary feature that aids in differentiating epidermolysis bullosa acquisita from bullous SLE is the absence of systemic manifestations of SLE. In addition, it shows a slow response to Dapsone therapy.
-
Dermatitis Herpetiformis produces itchy blisters on the skin. These blisters develop on the knees, elbows, hairline, and buttocks. It mostly resembles bullous SLE in the microscopic findings. Males between 30 to 40 years of age are more commonly affected.
-
Bullous Pemphigoid is considered to be a rare disorder that causes fluid-filled blisters over the skin (upper abdomen, thigh, armpits, etc.). They occur as a result of abnormal immune responses or due to certain medications. The blisters are usually large, reddish, or normal in color. A few mucosal lesions also occur. It is differentiated from bullous SLE through an immunofluorescence test.
Is Bullous Systemic Lupus Erythematosus Serious?
Bullous SLE may lead to the following complications if left untreated:
-
Infection of affected areas of the skin.
-
Mucosal sloughing from the esophagus may occur.
-
In addition, the side effects of certain medications may worsen the bullous SLE.
Is Systemic Lupus Erythematosus Treatable?
The medications used in the treatment of bullous SLE are listed down:
-
Dapsone is the most preferred drug, as it shows promising results. In addition, the side effects of Dapsone are considerably less.
-
Corticosteroids may help in case of intolerance to Dapsone or when the skin is extensively involved and other systemic manifestations.
-
Immunosuppressive medications like Azathioprine, Methotrexate, Cyclophosphamide, etc., may help to some extent.
-
Drugs like Rituximab also provide relief from painful blisters.
Conclusion:
Bullous systemic lupus erythematosus is a rare disorder, and it causes significant stress to the affected individual due to discomfort and unesthetic appearance. The dermatologist and other healthcare specialists need to diagnose the condition at the earliest to educate the patient on skin protection and improve the symptoms. Therefore, it is essential to note the early systemic signs. However, medication like Dapsone has shown tremendous response. Consequently, it is always crucial to visit the dermatologist to clarify skin lesions and their management to prevent further complications.