Cutaneous Anthrax and its Mimics
Cutaneous Anthrax
The primary lesion of cutaneous anthrax is a painless, pruritic papule that appears one to seven days after inoculation. Within one to two days, small vesicles or a larger, 1- to 2-cm vesicle forms that is filled with clear or serosanguineous fluid. As the vesicle enlarges, satellite vesicles may form. Fluid within the vesicles may contain numerous, large gram-positive bacilli. As the lesion matures, a prominent, non-pitting edema surrounds it. Eventually, the vesicle ruptures, undergoes necrosis, and enlarges, forming a painless ulcer covered by the characteristic black eschar. Symptoms include low-grade fever and malaise. Regional lymphadenopathy is present early on.

Used with Permission from the
Center for Public Health
and Disasters of California
Mimics
Differential Diagnosis of Ulceroglandular Syndromes
Cutaneous anthrax
Cutaneous leishmaniasis
Cat-scratch disease
Chancroid
Herpes simplex infection
Lymphogranuloma venereum
Melioidosis
Nocardiosis
Plague
Sporotrichosis
Staphylococcal/streptococcal adenitis
Tuberculosis
Tularemia
Differential Diagnosis of an Ulcer and Eschar
Cutaneous anthrax
Antiphospholipid antibody syndrome
Aspergillosis and mucormycosis
Brown recluse spider bite
Coumarin and heparin necrosis
Cutaneous leishmaniasis
Ecthyma and ecthyma grangrenosum
Factitious ulcer
Orf
Plague
Rickettsial pox and typhus
Tularemia
Search PIER® - Decision Support
ACP Members Only. Decision support for over 460 clinical topics.
Quality Improvement Programs: Our Quality Improvement programs strive to bridge the gap between research and practice.
Adult Immunization: Inform, Implement, Immunize: ACP's Immunization Outreach Program
Introducing ACP Summer Session
| The most popular learning formats from the Internal Medicine meeting offered at only $35 for ACP members! Combine CME and leisure time in San Francisco, CA or Orlando, FL | ![]() |


