What are the implications and management of preauricular pits?

Preauricular Pits: Clinical Implications and Management

Preauricular pits are generally benign congenital anomalies that require no intervention unless they become infected or are associated with other congenital anomalies, particularly in syndromic presentations.

Clinical Presentation and Epidemiology

Preauricular pits (ear pits) are common congenital abnormalities that manifest as small depressions adjacent to the external ear near the anterior margin of the ascending limb of the helix, most frequently on the right side 1. They can be either inherited (showing incomplete autosomal dominant pattern with reduced penetrance) or sporadic, with bilateral presentation in 25-50% of cases increasing the likelihood of inheritance 1.

When to Investigate for Associated Conditions

The critical decision point is whether the preauricular pit is isolated or associated with other anomalies:

Isolated Pits/Tags (No Investigation Needed)

• In healthy children with isolated preauricular pits or tags, routine investigation for renal abnormalities or hearing impairment is NOT necessary 2
• The prevalence of renal abnormalities (2.7%) and hearing impairment (2.7%) in children with isolated preauricular pits is similar to the general population (3.2% and 4.3% respectively) 2

Syndromic Presentations (Investigation Required)

• When other congenital anomalies coexist with preauricular sinuses, auditory testing and renal ultrasound should be performed 1, 3
• Preauricular sinuses are features of other conditions or syndromes in 3-10% of cases, primarily associated with deafness and branchio-oto-renal (BOR) syndrome 1, 3
• In 22q11.2 deletion syndrome, preauricular pits/tags may occur alongside microtia/anotia and other ear anomalies 4

Key red flags requiring workup:

• Family history of hearing loss or renal disease 2
• Presence of other congenital anomalies 1
• Bilateral presentation with dysmorphic features 1

Management of Infected Preauricular Sinuses

Acute Infection Management

• Culture exudates and administer appropriate antibiotics targeting gram-positive bacteria (most common pathogens) 1
• Recognize that infection may erupt away from the sinus opening, potentially affecting preauricular cheek skin 5
• A postauricular infected cyst may indicate the presence of a preauricular sinus - perform detailed physical examination for preauricular pits 6

Surgical Indications

• Recurrent infection is a clear indication for complete excision, which provides the only definitive cure 1, 5
• Single-stage excision can effectively treat infected preauricular sinuses 6
• Complete excision by an experienced head and neck surgeon is essential - recurrence rates after surgery range from 9% to 42%, with meticulous technique minimizing recurrence risk 1

Surgical Technique Considerations

• Use of operating microscope may aid in removing remnants and preventing recurrence 6
• Ensure complete identification of sinus extent - failure to recognize the full tract leads to inadequate treatment and unnecessary repeat procedures 5
• Remove the pit, involved cartilage, and entire sinus tract 6

Common Pitfalls to Avoid

• Do not perform simple incision and drainage alone - this is inadequate treatment that will lead to recurrence and may necessitate multiple unsuccessful procedures 5
• Do not miss the preauricular pit when evaluating postauricular or preauricular cheek infections - lack of awareness results in inadequate management 5, 6
• Do not order routine renal ultrasound and audiometry for isolated, asymptomatic preauricular pits in otherwise healthy children without family history or other anomalies 2