Lupus: Symptoms, Diagnosis, and Available Diagnostic Tests

Lupus

Lupus is a chronic, autoimmune disease in which the immune system—which normally protects our body—turns against itself and attacks it, causing inflammation and impairing the function of the affected system.

It is not a contagious, infectious, or malignant disease, but as a chronic disease, it has no cure. There may be periods of remission (during which the disease is “dormant” or inactive), allowing treatment to be paused for long periods of time or even for the rest of one’s life, and periods of flare-ups (during which the disease is active).

In some cases, a period of remission may become permanently inactive—that is, total remission—though this is a rare occurrence.

Partial remission (a limited period), on the other hand, is common; almost all patients experience partial remission at some point in their lives, especially when the disease is being treated effectively and appropriate preventive measures are followed. Periods of remission vary in duration and can last weeks, months, or years.

Lupus is a multifactorial disease. These causes or factors are genetic, hormonal, and environmental.

Triggering factors are situations that bring out (or make visible) the symptoms of lupus—that is, they cause the disease to manifest in obvious symptoms and signs—such as emotional stress, infections, pregnancy, sunlight, and fluorescent light, among others.

Who is affected?

Lupus can affect people of all ages, ethnicities, and genders.

However, more than 75% of people with lupus are women, most of whom are young women between the ages of 15 and 44.

Women of color are two to three times more likely to develop lupus than other ethnic groups.

Studies have shown that relatives of patients with autoimmune diseases (lupus, thyroiditis, rheumatoid arthritis, type 1 diabetes, Sjögren’s syndrome, antiphospholipid syndrome, …) are more likely to be affected by these diseases—that is, there is a family predisposition—but lupus is not considered a hereditary disease.

As for the probability that the child of a woman with lupus will also have it, it is 2%, while for other women it is 0.4%.

Generally speaking, “lupus” is used as a broad term, but there are three types of lupus:

Systemic Lupus Erythematosus (SLE) can affect various parts of the body, including the kidneys, the brain or central nervous system, the blood and blood vessels, the skin, the lungs, the heart, and the joints.
Discoid Lupus Erythematosus is a form of lupus that affects only the skin. “Discoid” means “disc-shaped” and describes the skin lesions. This form can progress to SLE.
Drug-induced lupus (drug-induced lupus erythematosus) occurs as a result of using certain drugs or medications. The symptoms are very similar to those of systemic lupus.

Symptoms

Lupus is difficult to diagnose because the symptoms come and go; they are not always present.

To diagnose lupus, the doctor must be able to find physical or laboratory evidence of the disease, such as joint swelling, protein in the urine, fluid around the lungs or heart, or a skin biopsy. The doctor will also review the patient’s medical history and order special tests to rule out other diseases.

Early detection and treatment are essential for improving health and can generally slow the progression and reduce the severity of the disease.

There are several symptoms of lupus, and not all of them may be present at the same time; some people experience only a few of them.

Doctors use the American College of Rheumatology’s “Eleven Criteria for Lupus” to confirm or rule out a diagnosis of lupus.

However, a person is considered to have lupus only if they meet at least four of these criteria:

The Eleven Criteria of the American College of Rheumatology

Malar rash: butterfly-shaped rash on the nose and cheeks
Discoid rash: red patches
Photosensitivity: a skin rash resulting from an unusual reaction to sunlight
Mouth or nose ulcers: usually painless
Arthritis (non-erosive) in two or more joints, along with swelling or effusion. With non-erosive arthritis, the bones surrounding the joints are not destroyed.
Cardiopulmonary involvement: inflammation of the membranes surrounding the heart (pericarditis) and/or lungs (pleuritis)
Nervous system abnormalities: seizures and/or psychosis
Renal (kidney) disorder: excess protein and sediment in the urine
Hematologic abnormalities: hemolytic anemia, low white blood cell count, or low platelet count
Immunological abnormalities
- Anti-ds-DNA, or
- Anti-Sm, or
- Antiphospholipid antibodies (APL) based on:
  - Abnormal levels of IgG or IgM anticardiolipin antibodies
  - Positive lupus anticoagulant by a standardized method
  - Confirmed false-positive serological test for Treponema pallidum for at least 6 months
ANA (antinuclear antibodies) in the absence of drug therapy

The diagnosis of lupus is based on clinical and laboratory findings.

Laboratory tests alone are not sufficient for diagnosis. In other words, a person may test positive for the test most commonly associated with SLE (ANA—antinuclear antibody) and still be perfectly healthy. However, when combined with the symptoms reported by the patient and the signs observed by physicians, these tests are very useful.

In some cases, diagnosis is difficult to establish because, although lupus is strongly suspected, the clinical data at that time are insufficient to make a diagnosis. In these cases, only the progression of the clinical situation will confirm the presence of the disease. On the other hand, lupus presents in many different ways, a fact that can also make diagnosis difficult.

The laboratory findings that suggest lupus are essentially:

Changes in the complete blood count (CBC):
- A decrease in red blood cells, also called erythrocytes, (anemia) due to their destruction (hemolytic anemia) or a decrease in their production (anemia associated with chronic disease),
- Decreased white blood cells, also known as leukocytes (leukopenia), and in particular a specific subtype of leukocytes: lymphocytes (lymphopenia)
- Decreased platelet count (thrombocytopenia)
Changes in inflammation markers:
- Elevated erythrocyte sedimentation rate (ESR)
Immunological changes:
- Presence of autoantibodies (substances that recognize and attack components of our own body):
- antinuclear antibodies (ANA)
- anti-dsDNA and anti-Sm antibodies
- anti-SS-A and anti-SS-B antibodies
- anti-RNP antibodies
- antiphospholipid antibodies (anti-cardiolipin, anti-β2-glycoprotein 1, etc.), often associated with thrombosis,
Decreased levels of certain complement components (substances that attack and destroy substances recognized by antibodies): C3, C4, and CH50.

Although all of these laboratory abnormalities may be present in the same patient, in many cases only some are present at a given stage in the same patient.

The results of these parameters should be interpreted by the patient’s attending physician, taking the clinical context into account.

The following tests should be performed as part of the initial diagnosis:

Complete blood count
Erythrocyte Sedimentation Rate (ESR)
Renal function (urea/creatinine)
ANA
Anti-dsDNA antibodies
Anti-Sm; U1 nRNP; SS-A; SS-B Antibodies
Antiphospholipid Antibodies
Complement factors C3 and C4; if both are normal, CH50
Other antibodies of interest:
- Anti-histone (drug-induced lupus)
- Anti-ribosomal P (neuropsychiatric manifestations)
- Anti-nucleosome

Lupus is generally treated by physicians specializing in Internal Medicine and Rheumatology. Specific manifestations of lupus, such as heart and kidney diseases, may be treated by physicians specializing in those areas.

The goal of lupus treatment is to prevent damage to vital organs and keep the disease in remission, thereby ensuring the best possible quality of life for the patient.

The treatment plan includes medication, appropriate exercise and rest, diet, and avoiding exposure to ultraviolet radiation and stress.

It is up to the patient to take all necessary measures to alleviate the symptoms of the disease and the side effects of medications, always keeping balance in mind in all aspects:

Avoid sun exposure (making the use of sunscreen a daily habit to protect the skin from sunlight is a preventive measure that should not be neglected)
Eat a healthy diet (low in calories to prevent weight gain, and low in salt to prevent water retention in the body, which causes swelling, especially in patients who regularly use corticosteroids)
Alcohol consumption should be occasional, and smoking should be completely avoided to prevent pulmonary complications, to which these patients are more prone
The joints are highly prone to inflammation; therefore, they should not be strained and require periods of rest each day, always with attention to proper body posture.
The areas where patients spend time should be well-ventilated and, as much as possible, free of artificial lighting and ultraviolet (fluorescent) light.
Regular physical exercise can help prevent muscle weakness and fatigue, helping the body eliminate toxins.
Medical prescriptions must be strictly followed
Many patients with lupus require psychological support.

Lupus varies widely in severity and can lead to very serious complications that require urgent attention. However, current treatments allow most patients to enjoy a good quality of life.

During disease monitoring, clinical tests should be performed regularly to determine disease activity parameters in an effort to predict a possible flare-up. These situations may suggest a change in treatment strategy.

To monitor disease activity, the following should be performed:

Complete blood counts
Erythrocyte Sedimentation Rate (ESR)
Renal function (urea/creatinine)
Anti-dsDNA antibodies
Complement factors C3 and C4; if both are normal, CH50
Anti-C1q for Lupus Nephritis

To prevent a lupus flare-up, you should

- Schedule routine checkups (especially during periods of increased stress, pregnancy, miscarriages, surgeries, etc.) to reassess symptoms, the signs observed by the doctor, and any tests and exams performed in the meantime, in order to adjust treatment as needed.
- Avoid stress
- Use sunscreen and appropriate clothing to prevent sun exposure (which can trigger not only skin flare-ups but also flare-ups in other organs such as the kidneys, lungs, etc.) and avoid exposure to fluorescent light, UV rays, etc.
- Get adequate rest (especially during periods of increased stress).
- Avoid excessive physical exertion
- Treat infections as early as possible
- Always seek advice on the best oral contraceptive (“the pill”), avoiding those with high doses of estrogen and hormone replacement therapy, which is often used by menopausal women. However, flare-ups can occur despite all the preventive measures you may take, for no apparent reason.

Pregnancy and the postpartum period can trigger a lupus flare-up.

A woman with lupus who is pregnant should discuss with her treating physician the potential risks she may face during these periods and try to follow the recommendations her doctor provides. Pregnancy should be planned, and a preconception consultation should be scheduled with an obstetrician experienced in caring for these patients.

Some medications used to treat lupus cannot be taken during pregnancy, which makes consulting with the treating physician very important when a woman is planning to become pregnant or as soon as she learns she is pregnant.

Whenever possible, pregnancy should be planned for a period when the disease is in remission.

Some women with lupus, especially those with coexisting antiphospholipid syndrome, may have some difficulty getting pregnant, but nowadays there are ways to mitigate this problem.