Lupus erythematosus is a rare autoimmune disease with unknown causes. The disease is difficult to diagnose, as the symptoms are not always specific to lupus erythematosus and may lead to a different diagnosis. However, a few tests that may reveal the presence of antibodies that cause lupus erythematosus, combined with a few symptoms, will lead to a clear diagnosis.
Symptoms of Lupus Erythematosus
Lupus erythematosus can be manifested through a wide range of symptoms; some of these symptoms may point to lupus erythematosus, while others may be mistaken for other diseases.
Patients with lupus may experience symptoms such as:
- Butterfly shaped rashes on the cheeks (specific to lupus erythematosus)
- Discoid skin rashes that leave scars
- Joint pain or swollen joints; visible deformation of joints
- Lesions (typically ring shaped)
- Photosensitivity, sensitivity to sunlight
- Lack of appetite
- Muscle pain
- Ulcers in the mouth, nose or throat
- Poor circulation, cold limbs and fingers
- Swelling of legs and feet
- Coughing and chest pain, caused by the inflammation of the lung or heart lining
- General state of weakness
- Behavioral changes
- Permanent hair loss where the lesions leave scars
If the disease involves organs, there may be symptoms that are specific to each organ affected.
Tests to Diagnose Lupus Erythematosus
In addition to the symptoms that may point to lupus erythematosus, the doctor may perform a test that will show the presence of antibodies specific to lupus. This test is known as ANA or the antinuclear antibodies test, which is positive if the patient has lupus erythematosus.
Criteria to Diagnose Lupus Erythematosus
Given that the ANA test may not always be positive, even if the patient has lupus erythematosus, there are 11 criteria that are used to diagnose lupus erythematosus. If the patient has 4 or more of these criteria, the diagnosis is clearly lupus erythematosus.
The 11 criteria are:
- The butterfly shaped rash
- Discoid skin rashes
- Sudden occurrence of ulcers on mucous membranes (mouth, nose, throat)
- Joint pain or swollen joints
- Pleuritis or pericaditis (swollen heart or lungs lining, leading to chest pain)
- Protein elimination through urine due to kidney lining inflammation
- Neurological signs such as seizures or psychosis
- Unusual blood count values (low red or white blood cell count)
- Positive ANA test
- Abnormal results to immunologic tests such as anti-DNA, anti Smith antibodies, false positive for syphilis or positive LE prep analysis
The doctor will also perform additional tests, as lupus erythematosus can easily turn into a systemic disease and involve the internal organs. Ideally, the function of all organs should be tested and monitored. Typically, the fist sign that lupus erythematosus turns into a systemic condition is that the kidneys are affected.
The doctor may also perform tissue biopsies (kidney, skin or nerve tissues).