Systemic Lupus Erythematosus

1- Clinic:

A- The dermatologic manifestations (80%):

– They predominate on exposed areas (photosensitivity);

– Erythema in vespertilio (60%) affects the nose and cheekbones.

– The discoid lupus (most readily observed in purely cutaneous chronic forms) is present in 15% of disseminated lupus. It combines three elementary lesions: erythema, dander and sequelae atrophy (scalp -> permanent alopecia)

– Less specific lesions: livedo, urticaria, purpura infiltrated puncture gangrene; alopecia.

B- Musculoskeletal manifestations:

– Inaugural Often, they are almost constant and readily figure prominently in the clinical picture. More often true arthritis (75%). Chronic arthritis is rare.

– The most frequently affected joints are: the metacarpophalangeal, proximal interphalangeal, carpus, knee and ankle.The deformities of the hands are rare and then reducible rheumatism Jaccoud).

– X-rays show no damage. Tenosynovitis can be observed or septic arthritis (more rarely)

C- Renal manifestations:

– They have a major prognostic importance. It is very common. A normal glomerulus in optical microscopy is rare.

– Histologically the most common form (and most serious) is diffuse proliferative glomerulonephritis (class IV).

– When lupus nephritis leads to kidney failure, scalability lupus tends to decrease. Hemodialysis survival rates are satisfactory, nephropathy of recurrence is exceptional after transplantation.

D- Other events:

– Adverse CNS: seizures, hemiplegia, aseptic lymphocytic meningitis

– Vascular Events: Raynaud’s phenomenon (25%), hypertension (40%); vasculitis (frequent); thrombosis (antiphospholipid Ab)

– Cardiac Events: steroid-pericarditis (30%); Libman-Sachs endocarditis

– Respiratory Events: pleurisy; PAH …

– Other Events: ADP are frequent; moderate hepatomegaly is frequently found (search Budd-Chiari): association with sicca syndrome (Sjogren) is often found.

2- Biology:

A- Inflammatory syndrome:

raised ESR, hyperfibrinémie, hyper-α2-glbulinémie. CRP remains low.

hypergammaglobulinaemia

B- Hematological event:

it focuses on the 3 lines:

– Inflammatory anemia, autoimmune hemolytic anemia (10%) sometimes revealing

– Moderate Leukopenia, resulting mainly from the T cell lymphopenia

– Thrombocytopenia device (10 to 20% of cases), linked to anti-platelet Ac

– The hemostasis disorders are dominated by the presence of anti-prothrombinase Ac (circulating anticoagulant lupus), it does not cause bleeding but instead of thrombosis within the scope of antiphospholipid syndrome.

C- Serologic abnormalities:

– Self-Ac varied characteristics are dominated by antinuclear factors (FAN) or antinuclear Ac. They are very sensitive (90%) by IIF on rat liver but poorly specific (best screening method).

– Search for LE cells became obsolete because of its lack of specificity

– The search for anti-double-stranded DNA Ac (native) is more specific but less sensitive (> 50%). Their rate is correlated with the presence of severe renal impairment. They help confirm the diagnosis.

– LES specific Ac Ag ENA (Ac anti-ENA) are detected by immunoprecipitation reaction in agar, several types:

* Anti-Sm Ac: uncommon (20%) and highly specific

* Ac anti-SS-A (anti-Ro)

* Ac anti-ribonucleoprotein (RNP) are found in 30% of 100% of lupus and mixed connective (MCTD)

– Other types of self-Ac: rheumatoid factor (30%); anti-erythrocyte antibody; anti-platelet, anti-lymphocytes;antiphospholipid

– Many autoantibodies are responsible for immune complex formation which are similar to the mixed cryoglobulins (present during flares)

– Hypocomplementemia: common (C3 and C4) by excessive consumption (which is correlated with severe renal impairment)

1- Antiphospholipid syndrome:

– The APS is defined by the combination of thrombosis or abortion and the presence of antiphospholipid Ac

– Two types of antiphospholipid Ac:

* Anti-prothrombinase (circulating lupus anticoagulant)

* Anti-cardiolipin (VDRL +) but negative TPHA

– It is found in other disease except the LED: connective not lupus, malignancies, renal failure, sometimes without any pathological framework.

2- Pregnancy:

The risk of serious outbreaks is important if the disease is progressive.

3- Induced Lupus:

– They are secondary to prolonged administration of some drug D-penicillamine, INH, chlorpromazine, some beta-blockers and anti-convulsants, minocycline.

– Combined pills are a special case because it is often responsible for lupus but do not induce a lupus thrust;

– The kidney and neurological damage are rare

– Particular biological Profile: very high rate of FAN (> 1/2000) contrasts with the usual absence of anti-dsDNA and hypocomplementemia.

– The inducer stop enough to regress lupus.