Systemic lupus erythematosus (SLE) is a chronic inflammatory disease which may affect many different organs and tissues in the body. Women of child bearing age are typically affected, but individuals of any age, sex, or race may develop the disease. SLE while uncommon, is not rare, with an estimated disease prevalence of 1 in every 2,000 population. It is a condition which appears to be increasing in prominence especially over the last 15 to 20 years.
This is likely explained by the earlier recognition of milder cases because of increased patient and physician awareness and by the enhanced availability of sensitive laboratory tests helpful in the diagnosis. Although the exact cause is not known, most of the features of the disease seem to be due to a fundamental abnormality of the body’s immune system. The immune system is the body’s defence mechanism against foreign substances entering the body.
It depends on the formation of compounds called antibodies and on hite cells called lymphocytes which rise to the defense of the body in case of invasion by foreign agents such as germs or viruses. This is a normal and desirable process in the healthy individual. In patients with SLE, there seems to be a defect in the body’s immune system whereby antibodies are mistakenly formed against the body’s own tissues. This leads to inflammation and damage in the tissues so affected. Patients with SLE can be identified by the presence of these abnormal antibodies in their blood stream.
It is not clear what triggers this immune abnormality but several factors seem to be contributory in some patients. These include infection, hormonal, genetic, and unidentified environmental factors. Some drugs including those used for the treatment of tuberculosis (isoniazid), high blood pressure (hydralazine), and convulsions (dilantin) have also occasionally been associated with the development of SLE. Clinical Features The majority of patients with SLE have very mild symptoms which can be easily controlled with simple measures.
A small minority have more serious manifestations which may require more aggressive forms of treatment. The seriousness of the disease is frequently related to the type and number of organs affected. The following is a summary of some of the signs and symptoms that may occur in lupus patients grouped according to the organs or tissues affected: General symptoms Fever and unusual fatigue occur in up to 80 or 90% of SLE patients at some time during the course of their illness. Skin rash a very common feature occurring in many patients.
The classic rash is called a butterfly rash because it occurs in a butterfly-like patch over the bridge of the nose and cheeks. This type of rash is in fact quite uncommon with most lupus rashes being far less specific and occurring anywhere on the body but especially over sun exposed areas. Many lupus rashes appear to be provoked or aggravated by direct sun exposure. Sores may also occur in the nose and mouth, and scalp hair loss may occur in some individuals. In a closely related condition called discoid lupus erythematosus (DLE), the rash may arise as distinct scaly and reddish patches which may heal with scarring.
Patients with DLE are frequently otherwise well. They demonstrate few, if any, of the symptoms of SLE and usually have a nearly normal laboratory profile. Joints – stiffness, pain, and swelling may commonly occur. Unlike rheumatoid arthritis however, permanent damage to the joints is almost unheard of. Membranes of the heart and lungs, the linings of the heart and lungs may occasionally become inflamed in SLE patients leading to sharp chest pains and shortness of breath. If it involves the lung, the condition is called pleuritis.
If it affects the heart, the condition is called pericarditis. Blood cells – a number of abnormalities may occur in the blood including anaemia or a fall in the red blood cell count and/or falls in the white cell count or platelet count (particles in the blood that help with clotting) and thus lead to potential problems with bleeding. Kidneys – often a sign of more serious disease, inflammation of the kidney may lead to loss of protein in the urine, increased blood pressure and occasionally kidney failure.
Brain and nerves – fortunately, a relatively rare problem, patients so affected may have trouble with headaches convulsions, emotional disturbances, weakness or numbness of the extremities. Diagnosis The diagnosis of SLE is suspected in any individual who presents with one or more of the clinical features outlined above. A diagnosis is confirmed by laboratory tests which show the presence of one or more abnormal circulating antibodies in the blood stream. These antibodies may be directed against any tissue in the body.
The most important of these however, is an antibody directed against the centre or nucleus of the cells in the body, the so-called anti-nuclear antibody or ANA. ANAs are normally not present or present only in barely detectable quantities in healthy individuals. Thus, this test is very helpful to the doctor if he is suspicious about the possibility of SLE. It is very important however, to stress that the presence of ANAs doesn’t specifically point to a diagnosis of SLE since abnormal antibodies of this type may occur in other conditions such as rheumatoid arthritis, certain infections and inflammation of the liver.
Thus the diagnosis of SLE requires both the presence of abnormal antibodies (especially ANAs) as well as signs and symptoms suggesting inflammation of several organs or tissues in the body. Although, all lupus patients have elevated levels of ANA, not all people with elevated ANA have lupus. Increased levels of ANA generally indicate that the physician should follow up with an anti-DNA antibody test. To assist in the diagnosis of SLE, the American Rheumatism Association (ARA) in 1982 adopted a set of criteria for the classification of this disease.
See Table 1) It should be noted that while a variable number of these features may occur during the course of the disease, they need not occur at the same time. Moreover, it is quite unpredictable as to which patient may develop which particular symptom or grouping of symptoms at any particular time. Management and Treatment The management of patients with SLE has three important components: Education of the patient and family, Medical treatment Follow-up. Education of the Patient and Family Educating the patient and family is essential in the management of SLE.
Patients and family are frequently misinformed about the disease and the time taken to correct and clarify any early misconceptions is greatly rewarding. A great deal of helpful information and support by persons similarly affected is also available through patient self-help groups such as the Lupus Society. It is also important for patients with SLE to realize the importance of good health habits in the control of their illness. This includes a well balanced diet, adequate rest, as well as physical activities tailored to the individual’s tolerance.
Most patients should also reduce direct sun exposure and consider the use of effective sun screen preparations. Preparations with a sun protection factor (SPF) of at least 15 and which block both UVA and UVB rays are recommended. Medical Treatment SLE is typically a disease which shows a fluctuating course characterized by long periods of relative inactivity (remission) punctuated by unpredictable flares of inflammation involving one or more organ systems (exacerbation). Fortunately for a majority of SLE patients, the symptoms are so mild as to require little or no specific treatment.
The choice of therapy will therefore depend both on the nature as well as the severity of the symptoms. The initial treatment of minor joint aches and pains may often consist of simple anti-arthritic medications sometimes known as non-steroidal anti-inflammatory drugs or NSAIDs. Skin rash can frequently be managed by avoidance of sunlight as well as the use of topical steroid creams as directed by the family physician. If the rash or arthritis is more troublesome, your doctor may consider a class of drugs still used for the treatment of malaria such as hydroxychloroquine or Plaquenil.
For patients with more serious symptoms such as severe fever, pleurisy or pericarditis, or falling blood count, it may be necessary to resort to the use of corticosteroids by mouth for a variable length of time. Unfortunately corticosteroids have a variety of side effects and your doctor will endeavour to taper and reduce the dosage as quickly as is medically possible. A relatively new approach called pulse steroid therapy involves the administration of very large doses of corticosteroid either orally or intravenously over a short period such as 1-3 days.
Pulse steroid therapy would seem to have the advantage of being relatively free of immediate and long term side effects. For the rare patient where steroids are inadequate, treatment is available with a number of more potent drugs specifically directed at suppressing the formation of the abnormal antibodies which occur in SLE. These drugs, examples of which include Imuran and Cyclophosphamide, are called cytotoxic or immunosuppressive agents. These drugs are frequently effective but may have serious side effects including the suppression of the body’s normal ability to fight infection.
An alternate non-drug approach to the management of SLE, especially severe kidney disease, may be sometimes considered. This procedure, which is called plasmapheresis, involves an exchange type transfusion whereby the red blood cells are removed from the blood and returned to the body while undesirable antibodies and complexes and the liquid part of the body’s blood (plasma) are discarded. This treatment seems most effective when combined with one of the cytotoxic or immunosuppressive drugs. Follow-up As the course of SLE may be unpredictable, close medical follow-up is essential.
This involves periodic assessment of disease activity by clinical history, physical examination and specific laboratory tests ordered by your doctor. Close follow-up during pregnancy and the immediate postpartum period is especially important as the risk of disease flare is increased during these periods. Inactive disease at the time of conception is associated with the best prognosis for both mother and baby. There is a slight but definite increased risk of miscarriage in mothers with lupus and their babies may have an increased chance of being born premature or with low birth weights.
Babies born to lupus mothers may also be at increased risk of developing lupus (neonatal lupus). This is probably due to the passage of abnormal antibodies through the placenta into the fetal blood stream. Neonatal lupus almost always resolves within 4-6 months of delivery. Babies born to lupus mothers may also be at increased risk of being born with an abnormality to the conduction system of the heart muscle. This may or may not be associated with other signs of neonatal lupus and seems to correlate closely with a very specific type of antibody in the mother’s circulation called the anti-Ro antibody.