title: Skin clues in the diagnosis of life-threatening infections.
abstract: Skin lesions, an important clue to the cause of septicemia, result from five main processes: (1) disseminated intravascular coagulation and coagulopathy; (2) direct vascular invasion and occlusion by bacteria or fungi; (3) immune vasculitis and immune complex formation; (4) emboli from endocarditis; and (5) vascular effects of toxins. Disseminated intravascular coagulation probably plays only a minor role in pathogenesis. Vascular invasion by bacteria may result in a severe inflammatory reaction, as in meningococcemia, or in a minimal reaction, as in ecthyma gangrenosum. Gram-stained smears of scrapings from the base of skin lesions--a frequently neglected procedure--is an important diagnostic adjunct. Skin biopsies are particularly important in the diagnosis of Rocky Mountain spotted fever and infections caused by Candida.
mesh_terms: D000936:Antigen-Antibody Complex / Q000032:analysis; D001427:Bacterial Toxins / Q000494:pharmacology; D002177:Candidiasis / Q000175:diagnosis; D003490:Cyanosis / Q000150:complications; D004211:Disseminated Intravascular Coagulation / Q000150:complications; D004617:Embolism / Q000150:complications; D005260:Female; D005734:Gangrene / Q000150:complications; D006069:Gonorrhea / Q000175:diagnosis; D006801:Humans; D008297:Male; D008585:Meningitis, Meningococcal / Q000175:diagnosis; D011552:Pseudomonas Infections / Q000175:diagnosis; D011693:Purpura / Q000150:complications; D012282:Rickettsia Infections / Q000175:diagnosis; D012480:Salmonella Infections / Q000175:diagnosis; D018805:Sepsis / Q000150:complications / Q000175:diagnosis*; D012867:Skin / Q000187:drug effects; D012871:Skin Diseases / Q000209:etiology*; D014657:Vasculitis / Q000276:immunology
chemical_list: D000936:Antigen-Antibody Complex; D001427:Bacterial Toxins