Systemic Lupus Erythematous

• Class I Minimal mesangialglomerulonephritis:Histologically normal on light microscopy but with mesangial deposits on electron microscopy.
• Class II Mesangial proliferative lupus nephritis: responds completely to treatment with corticosteroids.
• Class III Focal proliferative nephritis :Responds to treatment with high doses of corticosteroids.
• Class IV Diffuse proliferative nephritis:Treated with corticosteroids and immunosuppressant drugs.(most common)
• Class V Membranous nephritis :Extreme edema and protein loss.
• Class VI Glomerulosclerosis

• Most common rash is photosensitive, raised erythematousmalar rash. 55-85% develop at some point in disease
• Discoid Lupus Erythematosus (DLE): 15-30% circular, scaly hyperpimented lesions with erythematous rim, atrophic center—can be disfiguring
• Mouth/vaginal/nasal ulcers
• Alopecia: may be diffuse or patchy. Occurs 50%
• Polyarthritis, mild to disabling, occurs most frequently in hands, wrists, knees. Occurs 90%
• Joint deformities occur in only 10%
• Arthritis of SLE tends to be transitory
• Onion skin spleen is seen in SLE
• Spontaneous abortions and prematurity in patient with SLE planning for pregnancy
• If single joint has persistent pain, consider osteonecrosis (prevalence increased in SLE over general population, especially if on steroids.)
• Myositis with elevated CK and weakness rarely occurs

 Serositis

Pulmonary:

• Pleuritis with or without effusion
• If case is mild, tx: NSAIDS
• If case is severe, tx: steroids
• Life-threatening manifestations: interstitial inflammation which can lead to fibrosis and intra-alveolar hemorrhage.
• Also pneumothorax and pulmonary HTN can occur

Cardiac:

• Pericarditis: most common cardiac manifestation and usually responds to NSAIDs.
• Myocarditis (rare) and fibrinous endocarditis (Libman-Sacks) may occur. 
• Steroids plus treatment for CHF/arrhythmia or embolic events. 
• MI due to atherosclerosis 
• Maternal lupus erythmatosus has been associated with a high incidence of congenital heart block in offspring

Neuro:

• Cranial or peripheral neuropathy occurs in 10-15%, it is probably secondary to vasculitis in small arteries supplying nerves.
• Diffuse CNS dysfunction: memory and reasoning difficulty
• Headache: if excruciating, often indicate acute flare
• Seizures of any type
• Psychosis: must distinguish from steroid-induced psychosis (occurs in 1st weeks of tx at doses ≥40mg prednisone and resolves after several days of reducing or stopping tx)
• TIA, Stroke: mostly increased among patients that are APLA positive
• 50-fold increase in risk of vascular events in women under 45 compared to healthy women
• Treatment for clotting event is long-term anticoagulation

Heme:

• Autoimmune Hematolytic Anemia
• Leukopenia: almost always consists of lymphopenia, not granulocytopenia
• Thrombocytopenia 

Renal:

Lupus Nephritis:

• Wire loop lesions represent local Positive thickening of glomerular capillary walls

Immunoglobulins:

• Anti-dsDNA IgG: very specific, may correlate with disease activity
• Anti-Sm: specific, but only present in 25% of cases, does not correlate with activity
• APLA: not specific. Used to identify patients at increased risk for clots, thrombocytopenia and fetal loss
• Anti Ro:subacute cutaneous lupus erythematosus 

DIAGNOSIS:

American College of Rheumatology (ACR) criteria:

(SOAP BRAIN MD)

• Serositis
• Oral ulcers
• Arthritis
• Photosensitivity
• Blood disorders
• Renal involvement
• Antinuclear antibodies
• Immunologic phenomena (eg, dsDNA; anti-Smith [Sm] antibodies)
• Neurologic disorder
• Malar rash
• Discoid rash

Laboratory studies :

• CBC with differential
• Serum creatinine
• Urinalysis with microscopy
• Normal CRP with elevated ESR
• Complement levels
• Liver function tests
• Creatine kinase assay
• Spot protein/spot creatinine ratio
• Autoantibody tests
• Lupus band test

Imaging studies: 

• Joint radiography
• Chest radiography and chest CT scanning
• Echocardiography
• Brain MRI/MRA
• Cardiac MRI 

Procedures 

• Arthrocentesis
• Lumbar puncture
• Renal biopsy

TREATMENT:

 Conservative Management:

• NSAIDs: to control pain, swelling, and fever
• Antimalarials: Generally to treat fatigue joint pain, skin rashes, and inflammation of the lungs
• Commonly used: Hydroxycholorquine
• Corticosteroids (Mainstay of SLE treatment)
• To rapidly suppress inflammation
• Commonly used: prednisone, hydrocortisone, methylprednisolone, and dexamethasone

Immunosuppressives:

• Primarily for CNS/renal involvement
• Mycophenolatemofetil
• Azathioprine
• MTX: for treatment of dermatitis and arthritis, not life-threatening disease
• Cyclosporine: used in steroid-resistant SLE, risk of nephrotoxicity
• Cyclophosphamide: patients with nephritis