Loxoscelism is the clinical picture secondary to the spider bite of the genus Loxosceles laeta, which presents a limited form of hematuria to the skin and a systemic form (loxoscelism, visceral fever).
Necrotic cutaneous loxocelism presents livedoid plaque within the first 24 h, a product of vasculitis secondary to bite and inoculation of the poison.
It is a painful plaque surrounded by an erythematous halo.
It detaches from the formation of a necrotic cyst leaving an ulcer that heals slowly.
Treatment consists of local ice, limb elevation, systemic corticosteroids, analgesia and antihistamines.
Anti-loxoscele serum that should be administered within the first 4 hours of the bite can be used.
