Anthrax - Symptoms, Causes, Images, and Treatment Options

Diseases

Highlights & Basics

Key Highlights

Anthrax is a notifiable condition. Bacillus anthracis spores are potential agents of biologic warfare as they are easily disseminated and are resistant to heat, light, and radiation.
Cutaneous anthrax is the most common type, accounting for approximately 95% of cases. Inhalation, ingestion, and injection anthrax, as well as anthrax meningitis, are less common.
Microbiology and pathology testing are used to confirm the diagnosis. Chest x-ray and CT scan are useful diagnostic tools in cases of inhalation anthrax.
Initial therapy includes treatment with empiric antimicrobial drugs and appropriate supportive therapy. Once susceptibilities are available, antibiotic treatment may need to be modified. Anthrax antitoxins may be used in some patients.
Postexposure prophylaxis is recommended to prevent infection after known or suspected exposure to aerolized B anthracis spores, and consists of a single antimicrobial drug (or an anthrax antitoxin as an alternative if antimicrobial drugs are not available), plus an anthrax vaccine, if indicated.

Mild cutaneous anthrax

www.cdc.gov

Quick Reference

History & Exam
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Treatment Options
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Definition

Epidemiology

Etiology

Pathophysiology

Images

Gram stain of blood in culture media. Gram-positive bacilli in chains at 20x magnification (panel A) and 100x magnification (panel B)
Mild cutaneous anthrax
Chest x-ray findings of inhalation anthrax
Chest CT reveals perihilar lymphadenopathy, perihilar infiltrates, and a widened mediastinum

Citations

Key Articles

Bower WA, Yu Y, Person MK, et al. CDC guidelines for the prevention and treatment of anthrax, 2023. MMWR Recomm Rep. 2023 Nov 17;72(6):1-47.[Abstract][Full Text]
Bower WA, Schiffer J, Atmar RL, et al; ACIP Anthrax Vaccine Work Group. Use of anthrax vaccine in the United States: recommendations of the Advisory Committee on Immunization Practices, 2019. MMWR Recomm Rep. 2019 Dec 13;68(4):1-14.[Abstract][Full Text]
World Health Organization. Anthrax in humans and animals. 4th ed. 2008 [internet publication].[Full Text]

Other Online Resources

BMJ talk medicine podcast: anthrax
CDC: history of anthrax
CDC: recommended specimens for microbiology and pathology for diagnosis of anthrax
CDC: guidelines for the prevention and treatment of anthrax 2023

Referenced Articles

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