Non-rheumatoid erosive arthritis associated with type I hereditary angioedema

Hereditary angioedema (HAE) is an autosomal dominant disease that causes recurrent attacks of non-pitting edema of soft tissues, without pruritus. This disorder can also affect internal organs. The cause of HAE consists in quantitative or qualitative defective production of C1 inhibitor (C1-INH). Many autoimmune diseases such as systemic lupus erythematosus (SLE) (or SLE-like syndromes), Sjögren's syndrome, scleroderma, thyroiditis, glomerulonephritis, and inflammatory bowel disease have been described in patients suffering from HAE. A concomitance with pure arthritis was previously reported only in two adult patients. Here, we describe for the first time the association between HAE and a non-rheumatoid erosive oligoarthritis involving hips and wrists.