[The blue tests. Current data concerning its indications and interpretation (author's transl)].

The blue test is designed to reveal oedema of total or partial lymphatic origin. It consists of the subcutaneous or intradermal injection in oedematous areas of a very small amount of violet patent blue and study of its resorption. The diagnosis is immediate and although reliability is not absolute it is nevertheless highly constant. Intolerance to the dye injected is rare, though sometimes severe, and users should be aware of the possibility. The Blue test remains of great interest in angeiology.