Systemic Lupus Erythematosus (SLE)

Definition

 

Systemic Connective Tissue Disease

 

Chronic inflammatory disease resulting from abnormal immunoregulation

 

Aetiology

 

Unknown

 

Thought similar to RA

1.  Genetic factors

2.  Environmental factors

 

Epidemiology

 

Young females

 

F:M 9:1

 

Peak 35 years old

 

Geographic variations

- more common in black and asian populations

 

Clinical Features

 

Affects many organ systems

- bones / joints / tendons / skin

- heart / kidney / CNS

 

Systemic

- malaise / fever / anorexia / weight loss

- skin rashes / photosensitive butterfly rash 

- Reynaud's Phenomenon / peripheral vasculitis

- splenomegaly

- largest cause of mortality is CRF

 

Joint involvement

 

Presenting complaint in >90%

- red swollen joints

- usually involves small joints & knees 

- symmetrical involvement

 

Morning stiffness in 50%

 

Longstanding disease may produce RA like deformity

 

AVN

 

Predisposes to bone ischaemia

- aggravated by steroids

- classically in talus

 

DDx RA

 

1. No ankylosis or contractures

2. No erosive changes on xray

3. Less destructive than RA

 

Investigations

 

ANA positive / antinuclear antibodies

- screening tool

- positive in other CT diseases and normal people

 

dsDNA / anti double stranded DNA

- highly specific for SLE

 

C3/C4

- low levels complement secondary to consumption

 

antie-ENA / anti extractable nuclear antigen

 

Elevated ESR

 

Anaemia / Leucopaenia / Thrombocytopaenia

 

Management

 

Medical

 

Avoid sunlight as it exacerbates symptoms

 

Options

 

NSAIDS

Steroids

Cyclophosphamide

DMARDS

Anti-immune as per RA

IV immunoglobulin

        

Arthroplasty

 

Higher risk of deep infection