Abscess
An infected wound containing pus is called an abscess.
Definition and Clinical Terminology
An abscess is the precise medical term for a localized collection of pus within infected tissue. This terminology is clinically crucial because it directly determines treatment approach 1.
Critical Distinction from Cellulitis
It is essential to distinguish abscesses from cellulitis, as the IDSA guidelines explicitly state that the term "cellulitis" should NOT be used for cutaneous inflammation associated with pus collections 1. Key points:
- Cellulitis = diffuse, superficial, spreading skin infection without pus collection
- Abscess = localized purulent collection requiring drainage
- When redness surrounds a pus collection, the correct terminology is describing the purulent focus (e.g., "abscess with surrounding inflammation"), not "cellulitis"
Why This Distinction Matters
The primary treatment of an abscess is incision and drainage, whereas cellulitis requires antimicrobial therapy 1. Misclassifying an abscess as cellulitis leads to inappropriate treatment with antibiotics alone when surgical drainage is actually needed.
Related Terminology
Other terms for specific types of purulent collections include:
- Furuncle (boil) - infected hair follicle with pus
- Septic bursitis - infected bursa with pus
- Carbuncle - cluster of interconnected furuncles
Common Pitfall
The presence of pus is the defining feature that distinguishes purulent infections (abscesses) from non-purulent infections (cellulitis), and this distinction must guide your treatment algorithm: drainage for pus collections, antibiotics for diffuse spreading infection 1.