Loxoscelism, is caused by the bite of Loxosceles laeta spiders. It has two clinical, forms: cutaneous loxoscelism (CL) and viscerocutaneous loxoscelism (VCL). VCL is characterized by hematuria, hemoglobinuria, jaundice, fever and sensorial involvement. In severes cases there is massive hemolysis and renal failure, with high letality. We report a 77 year-old man, brought to the hospital five clays after suffering a spider bite. The patient was admitted with a severe kidney,failure, hemolysis, metabolic acidosis and clotting disorder. The patient was managed with adrenal steroids and dialisys but died five weeks after hospital admission. This particualr patient consulted late and had multiple factors of poor prognosis. (Rev Med Chile 2005; 133: 219-23).