MusculoskeletalPending review

Systemic Lupus Erythematosus

A multisystem autoimmune disease in which loss of tolerance to nuclear antigens generates immune complexes that deposit wherever they lodge, igniting complement-driven inflammation in the skin, joints, kidneys, serosa and brain alike.

In a nutshell

Failure to clear nuclear debris leads to autoantibodies against nuclear antigens, which form immune complexes that deposit wherever they lodge and trigger complement-driven inflammation. This single mechanism explains the multisystem pattern of skin, joint, renal, serosal and neuropsychiatric disease, and anti-dsDNA/complement levels track how active it is.

Classic presentation

A woman of reproductive age with fatigue, symmetrical small joint pains, a photosensitive malar rash, oral ulcers and unexplained cytopenia, with a positive ANA.

Key points

ANA is the most sensitive screening test; a negative ANA makes SLE very unlikely, though a positive ANA alone is not diagnostic.

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Educational content pending clinical review. Not medical advice.