American Board of Internal Medicine (ABIM) Certification Practice Exam

Which organisms can cause cellulitis via direct inoculation through skin trauma?

1. Vibrio species

2. Mycobacterium species

3. Aeromonas and Bacillus species

4. All of the above

The correct answer is: Vibrio species

Cellulitis is a common skin infection that can occur when bacteria enter through a break in the skin. Certain organisms are more commonly associated with cellulitis, especially when there is a direct inoculation due to skin trauma. Vibrio species, for instance, are known for causing cellulitis, particularly in individuals who have been exposed to contaminated water or who have wounds that have come into contact with the ocean. This is particularly relevant for those with certain underlying conditions that may predispose them to infection, such as liver disease. While Mycobacterium species can cause a variety of skin infections, they are typically more associated with conditions like leprosy or atypical mycobacterial infections rather than cellulitis specifically from direct inoculation. Aeromonas and Bacillus species can also be involved in skin infections but are less commonly recognized as primary pathogens causing cellulitis through skin trauma when compared to Vibrio. This context indicates that while multiple organisms can lead to skin infections when introduced through skin trauma, Vibrio is distinctly known for its association with cellulitis due to specific environmental exposures, making it the most relevant choice in this scenario. Therefore, the answer focuses appropriately on Vibrio species as the primary causative agent in this context.