title: Solar urticaria. A case with possible increase of skin mast cells.
abstract: A case of solar urticaria is described showing: (I) Action spectra for late erythema (MED), late swelling and wealing with one peak of sensitivity for erythema and wealing at 405 nm.  (2) No signs of porphyria. (3) Possibly increased skin mast cells. (4) Short-lived post-irradiation fibrin deposition. (5) Haemolysis. (6) Apparent suppression of urticaria with the antihistamine Incidal.
mesh_terms: D002243:Carbolines / Q000627:therapeutic use; D006634:Histamine H1 Antagonists / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008407:Mast Cells; D008875:Middle Aged; D011830:Radiation Effects; D012867:Skin / Q000473:pathology* / Q000528:radiation effects; D013472:Sunlight; D014466:Ultraviolet Rays; D014581:Urticaria / Q000188:drug therapy / Q000473:pathology*
chemical_list: D002243:Carbolines; D006634:Histamine H1 Antagonists