Lupus Vulgaris

L. vulgaris is characterized by the development of tubercles within or projecting to a greater or less degree above the surface of the skin. It rarely appears as an isolated tubercle, but more frequently in groups of six or a dozen tubercles, quite close to, but not touching one another, little bands of apparently healthy skin intervening, thus forming a patch. As the disease progresses, however, the tubercles may unite by mutual extension and the entire patch present a lupous character. There may be one or more of these patches. The tubercles themselves are soft, sometimes almost jelly-like, in appearance and consistence. The extension of the lesions is slow, years intervening before the patches attain any notable size.

Just as in the erythematous variety, the lesions of lupus vulgaris may undergo resolution, leaving a depressed cicatrix, or else they may ulcerate superficially. The ulcera-tive action is exceedingly slow, and appears to involve only the upper portion of the derm - more rarely its entire thickness. The exudation from the surface of the ulcer is exceedingly scanty, and forms a crust adhering somewhat closely to the sore. The scars that result are of a reticulate character, not unlike those produced by a severe burn, and naturally cause more or less disfigurement. Lupus vulgaris, after ulceration takes place, may be succeeded by epithelioma at the margins of the ulcer.