Medical Wikipedia : The Medical Encyclopedia
Systemic Lupus Erythematosus
Systemic Lupus Erythematosus is an autoimmune disease that affects multiple systems of the body.
The presentation of the disease varies from patient to patient and may range from
mild cutaneous involvement to severe damage to the CNS and multiple organs.
Also called as:
- LE syndrome
- Libman-Sacks disease
- Disseminated lupus erythematosus
- Lupus
SYSTEMIC LUPUS ERYTHMATOSUS
It is an autoimmune disease that affects multiple systems of the body. The
presentation of the disease varies from patient to patient and may range from
mild cutaneous involvement to severe damage to the CNS and multiple organs.
The exact etiology of SLE is not known. Several genetic, immunological,
endocrine and environmental factors are believed to play a very important role in
the pathogenesis of SLE.
Etiology
SLE has multifactorial origin with an unknown exact cause. It's presumed
that SLE is caused by genetic susceptibility with an environmental
trigger. That cause defects of the immune system. vitamin D deficiency is associated with SLE.
Genetics
1. Genetics:
Genetics is believed to contribute strongly to SLE development. . More
than 50 genes are identified with association to SLE and most of
them code for proteins implicated in immune system. Mutations in these
genes causes deficiency of components of the immune system like the
complement proteins C1q, C1r, C1s, C4 and C2 together with TREX1 (3’-5’
Exonuclease). Some genes involved in SLE are the genes coding for HLA
class I, class II and class III genes (HLA-DRB1, HLA-DR2, HLA-DR3), IRF5-TNPO3,
ITGAM and BANK1.
Drug Induced
2. Drug Induced:
Drug Induced Lupus Erythmatosus presents similar
symptoms like SLE but is caused by chronic drug use for treatment of long-term
illness. It doesn’t persist for long after the drugs are discontinued. Some of the
most common causes of drug induced SLE is the administration of the following
drugs: hydralazine, procainamide, quinidine, with hydralazine being the most
common cause by far. Hydralazine is useful treating hypertension and
heart failure.
Pathophysiology
SLE is a chronic condition because of type III hypersensitivity response. Reticulate
and stellate acral pigmentation with high titer of anti-cardiolipin
antibodies are an indicator of possible SLE. People with SLE have increased
polyclonal B cell activation, which results in increased B cell count. T cells
regulate the response of B-cells and infiltrate target tissues, have signaling defects ,
adhesion, co-stimulation, gene transcription, and alternative splicing. Low
complement protein C3 levels are seen in SLE.
The pathogenesis of SLE occurs by stimulation of both innate and acquired
immune systems.
In the Innate immune system, activation can either be dependent on Toll-like
receptors (TLR) or be TLR-independent. TLRs are stimulated by exposure to
extracellular DNA and RNA, along with demethylated DNA. This leads to
downstream activation of Interferon Regulatory Family (IRF-3) and further
leads to release of pro-inflammatory mediators. Neutrophils also play a role in
activation of the innate immune system by releasing their granular contents
into the extracellular space.
T cells and B cells are also involved in the pathogenesis of SLE. Expression of
Fas ligand on both cells increases and T cells are programmed to release more
cytokines for activation of B cells.
Signs and Symptoms
Skin lesions
1. Skin lesions are commonly seen. Red scaly patches of skin, rashes, hair
loss and mouth and nasal ulcers are common. Lesions on the skin can be
categorized into chronic cutaneous (discoid) lupus, subacute cutaneous
lupus and acute cutaneous lupus.
Joint
2. Most common symptom is Joint pain and is the main chief complaint
in patients with SLE.
3. Anemia is seen along with low platelet count and low WBC count in
some cases. Autoantibodies to phospholipids and cardiolipins are
detected in blood, along with prolonged partial thromboplastin time
(PTT).
Carditis
4. Any one of Pericarditis, Myocarditis or Endocarditis may be seen in SLE.
The Endocarditis in SLE is non-infectious and is called Libman-Sacks
endocarditis.
Pleuritis
5. Pleuritic pain and Pleurisy are seen in SLE, which results in reduced lung
volume.
Lupus nephritis
6. Lupus nephritis is a well-known and common complication of SLE. The
involvement may be mild subnephrotic proteinuria to severe cases with diffuse
progressive glomerulonephritis causing chronic kidney damage. Lupus
nephritis usually seen early in SLE disease course. New-onset
hypertension, hematuria, proteinuria, lower extremity edema, and
increased creatinine levels suggests lupus nephritis. Renal Biopsy
helps in staging the lupus nephritis and rules out other renal causes.
Neuropsychiatric syndromes
7. Neuropsychiatric syndromes can result when SLE affects the central or
peripheral nervous system. The most common neurological symptom of
SLE is intractable headaches. Other manifestations can be Mood
disorders, Cognitive Dysfunction, Cerebrovascular disease, Seizures,
Polyneuropathy, Anxiety disorder, Psychosis, Depression and so on. Rare
conditions like Guillain-Barre Syndrome and demyelinating syndrome
are also seen in SLE. Neurological disorders contribute to a significant
percentage of morbidity in patients with SLE.
Eye involvement
8. Eye involvement is seen in one-third of SLE patients. Dry eye syndrome
and Secondary Sjogren syndrome are the most common manifestations,
along with Ischemic optic neuropathy, retinopathy and glaucoma.
Abortion
9. SLE is a cause of increased rate of fetal death and spontaneous abortion
in pregnant women.
Muscle pain
10. Fatigue and muscle pain are some other complaints seen in SLE.
Treatment
There is no cure for SLE. The treatment involves preventing flares and reducing
the severity and duration of any flare-up of symptoms that is seen.
Medication for SLE
1. Medication for SLE is given to prevent and treat flares that is commonly observed.
Mainstay of treatment in SLE:
- NSAIDs
- Corticosteroids
- Immunosuppressants
- Hydroxychloroquine
- Methotrexate
DMARDs
Disease-modifying antirheumatic drugs (DMARDs) are given to
preventively reduce the incidence of flares.
Corticosteroids and Hydroxychloroquine
Corticosteroids and Hydroxychloroquine
are used to treat flares. Hydroxychloroquine in particular
is approved for treatment of SLE with other drugs.
Cytotoxic drugs
2. Cytotoxic drugs like cyclophosphamide and mycophenolic acid are used
to treat Lupus Nephritis.
Lifestyle changes
3. Lifestyle changes like avoiding sunlight and avoiding activities that cause
fatigue are important.
Kidney transplantation
4. Kidney transplantation may be required for Lupus patients who have
end stage renal disease.
Pregnancy
5. Proper management of pregnancy in mothers who have SLE is
important, as infants born to such mothers are usually healthy. Women
are also advised against conception while having SLE because it can be harmful
for the baby.
QUESTIONS & ANSWERS
What are the common symptoms of SLE?
Common symptoms of SLE are
Early in the disease course we may notice -
- Extreme tiredness (fatigue)
- Malaise
- Fever
- Loss of Appetite
- Weight Loss
As the disease progress we may notice -
- Joints involvement - pain and swelling of joints
- Chest pain
- Hair loss
- Mouth ulcers
- Swollen lymph nodes
- Red rash
Most common site for rash in SLE?
- Face - is commonest site
- Red and butterfly-shaped rash
- Cheeks and Nose are common to be affected
- Following exposure to sunlight
Why the rash in SLE is called as 'Butter Fly Rash'?
Characteristic feature of the rash in SLE :
- Flat red coloured rash in the cheeks and bridge of the nose.
- Because of its shape it is called as - "butterfly rash"
- Rash is painless. No itching found in the rash area.
- The rash looks more prominent when exposed to sunlight.
In case of identical twins, if one is affected then what is the chance that another child also will be affected?
In identical twins if one is affected then there is 24% chance that the other child will also be affected in SLE.
What are the other names for SLE?
- LE syndrome
- Libman-Sacks disease
- Disseminated lupus erythematosus
- Lupus
Most common cause of death in SLE?
SLE has high risk of cardiovascular disease
Cardiovascular disease is the most common cause of death in SLE patients.
What is the Great
Why SLE is is included in the list of The Gear Imitator as medical conditions?
SLE is mistaken for other illnesses and behaves like other diseases masking the original diagnosis.