H70.819 Postauricular fistula, unspecified ear

Name of the Condition

• Postauricular fistula, unspecified ear

Summary

Postauricular fistula, unspecified ear, is a congenital or acquired abnormal tract connecting the skin behind the ear to deeper structures, such as the mastoid bone or middle ear. It may present as a small opening, sinus, or cyst and can be associated with chronic discharge or recurrent infections. The condition is typically benign but may require intervention if symptomatic.

Causes

Postauricular fistula is most commonly congenital, resulting from incomplete closure of the branchial cleft during embryonic development. Acquired cases may arise from chronic infections, trauma, or surgical complications. The tract forms a direct pathway between the skin and underlying structures, facilitating drainage or infection.

Risk Factors

• Congenital predisposition (family history)
• Chronic ear infections (otitis media)
• Previous ear surgery or trauma
• Immunocompromised states
• Poor hygiene or recurrent skin infections

Symptoms

• Small opening or pit behind the ear
• Persistent or intermittent discharge
• Swelling or redness around the fistula
• Pain or tenderness
• Recurrent infections or abscess formation
• Possible hearing changes if the fistula connects to the middle ear

Diagnosis

Diagnosis is typically made through physical examination, noting the characteristic opening behind the ear. Imaging studies, such as CT scans, may be used to assess the tract's extent and any associated complications. Clinical history and presentation help differentiate congenital from acquired cases.

Treatment Options

Treatment depends on symptoms and severity. Asymptomatic cases may require no intervention. Symptomatic cases may involve antibiotics for infections, incision and drainage of abscesses, or surgical excision of the fistula tract to prevent recurrence.

Prognosis and Follow-Up

Prognosis is generally good with appropriate treatment. Recurrence is possible if the tract is not fully excised. Follow-up may include monitoring for infection or complications, especially if surgery was performed.

Complications

Potential complications include chronic infections, abscess formation, hearing loss (if the fistula connects to the middle ear), or scarring from recurrent episodes.

Lifestyle & Prevention

Maintaining good ear hygiene and managing chronic ear infections may reduce the risk of acquired fistulas. Congenital cases cannot be prevented, but prompt treatment of infections can minimize complications.

When to Seek Professional Help

Seek medical attention if there is persistent discharge, pain, swelling, or signs of infection (e.g., fever, redness). Recurrent infections or abscesses also warrant evaluation.

Tips for Medical Coders

Use H70.819 for postauricular fistula when the ear is unspecified. Document the location (unspecified) and whether the condition is congenital or acquired, as this may impact coding and billing. Ensure clinical documentation supports the diagnosis and any associated symptoms or complications.