CHAPTER 31 – Anthrax

Publisher Summary Anthrax is a virulent, contagious, and potentially fatal disease. Depending on the route of exposure, anthrax can cause a different disease, including inhalational, cutaneous, and oral/ingestional forms. Anthrax infection involves a complex set of steps in its pathogenesis from spore uptake by immune cells, germination, transport to local lymph nodes, production of deadly toxins, systemic spread, and ultimately death of the host. Themes common among all anthrax infections are: uptake by macrophages and other immune cells, germination to the vegetative form at or near the site of inoculation prior to transit to target tissues, time course of transport to target organs, organs targeted for toxicity, overwhelming septicemia, and release of soluble factors responsible for death. Two types of B. anthracis have been identified: a spore form and a vegetative form. Some of the most common findings in human inhalational anthrax concern the respiratory tract. Pathological findings from inhalational anthrax patients in a bioterrorism-related outbreak cited hemorrhage and necrosis in mediastinal lymph nodes, hemorrhage, or inflammation of the pleurae and interhilar septae, and prominent intraalveolar macrophages or inflammation in the lung parenchyma. Treatment of any form of anthrax infection is generally the same: aggressive antibiotics and supportive care. Intravenous ciprofloxacin or doxycycline is recommended for treatment of anthrax, usually as part of a cocktail of antibiotics.