Angioedema and systemic lupus erythematosus--a complementary association?

INTRODUCTION We report angioedema as a rare presentation leading to a diagnosis of systemic lupus erythematosus (SLE). CLINICAL PICTURE A diagnosis of angioedema was delayed in a patient presenting with limb and facial swelling until she developed acute upper airway compromise. After excluding allergic and hereditary angioedema, acquired angioedema (AAE) was suspected, possibly precipitated by respiratory tract infection. Associated clinical and laboratory features led to a diagnosis of SLE. TREATMENT Management proved challenging and included high dose steroids and immunosuppressants. OUTCOME The patient responded to treatment and remains in remission without recurrence of the angioedema. CONCLUSION AAE occurs due to the acquired deficiency of inhibitor of C1 component of complement (C1 INH). Lymphoproliferative disorders and anti-C1 INH antibodies are well-described associations. However, one should also consider the possibility of SLE.