What is the name for a pimple or infection on the external auricle?

Terminology for External Auricular Infections

The specific term for an infected hair follicle or pimple on the external ear canal is "furunculosis" (also called localized otitis externa), while infection of the auricular cartilage itself is termed "auricular perichondritis." 1

Furunculosis (Localized Otitis Externa)

Furunculosis represents an infected hair follicle specifically located on the outer third of the ear canal, presenting as a localized infection rather than diffuse canal inflammation. 1

Clinical Presentation

• Patients present with otalgia, otorrhea, localized tenderness, focal swelling, and pustular lesions confined to the hair-bearing outer third of the canal 1
• The infection remains localized rather than involving the entire canal, distinguishing it from diffuse acute otitis externa 1

Causative Organism and Treatment

• Staphylococcus aureus is the most common causative agent of furunculosis 1
• Treatment includes local heat application, incision and drainage when indicated, or systemic antibiotics targeting S. aureus 1

Auricular Perichondritis

Auricular perichondritis is a more serious bacterial inflammation affecting the perichondrium and cartilage of the external auricle, typically sparing the earlobe which lacks cartilage. 1, 2

Clinical Features

• Presents as painful swelling, warmth, and redness in the cartilaginous portion of the auricle that characteristically spares the earlobe 1
• Acute tenderness on deflecting the auricular cartilage helps distinguish this deeper perichondrial infection from superficial skin infections 1
• Typically occurs within the first month after ear piercing, especially during warm-weather months 1

Microbiology

• Pseudomonas aeruginosa* is the predominant pathogen (69% of isolates), followed by S. aureus and *S. pyogenes 1, 3
• The presence of P. aeruginosa is associated with more advanced clinical presentation and longer hospitalization 3

Treatment Approach

• Fluoroquinolone antibiotics (ciprofloxacin or levofloxacin) are first-line therapy due to excellent coverage against P. aeruginosa 1
• Alternative hospitalization options include clindamycin, ceftazidime, and cefepime depending on the pathogen 1
• If abscess formation occurs, surgical incision and drainage are necessary, though preserving good cosmetic appearance of the auricular cartilage becomes difficult once abscess develops 1
• Minor infections can rapidly progress to perichondritis, abscess formation, and cartilage necrosis with or without systemic symptoms, making prompt recognition and treatment essential 1

Critical Pitfall

• Delayed or inadequate treatment can lead to permanent auricular deformity from cartilage necrosis, as the infection destroys the structural framework of the ear 2, 3