Angioedema: a 24-hour photo diary by a patient posted on Flickr
The patient took pictures of herself and uploaded them to the photo sharing website Flickr under a Creative Commons license. She had the impression her symptoms were due to urticaria but since the process affects the subcutaneous tissues (note the upper lip edema), the more likely diagnosis is angioedema and urticaria.
Dr Heinrich Quincke first described the clinical picture of angioedema in 1882, hence the eponym Quincke's edema. Sir William Osler remarked in 1888 that some cases may have a hereditary basis; he coined the term hereditary angio-neurotic edema.
C1 protein, showing subunits C1r, C1s, and the C1q tails. Image source: Wikipedia. Patients with acquired angioedema have low C1q levels AND low C4/C2 levels. In contrast, in hereditary angioedema (HAE) the C1q level is normal.
Classical and alternative complement pathways. Image source: Wikipedia.
Read more about Angioedema at AllergyCases.org.
Link via AllergyNotes.