Definition

A preauricular fistula (preauricular pit) is a small hole in front of the ear, resembling a puncture mark or piercing hole. This condition occurs in about 5-10 children out of every 1,000 births. According to the American Academy of Family Physicians (AAFP), approximately 1% of babies are born with a preauricular pit, while in Africa, around 10% of babies have this condition.

This small hole, a narrow tract under the skin, is generally not dangerous, though it can sometimes become infected. The size of the hole varies and it usually appears in front of one ear.

Causes

A preauricular fistula forms due to disturbances during ear development in the sixth week of fetal growth. Experts believe an inherited genetic factor causes this condition. When preauricular fistulas appear on both ears, it may indicate an inherited condition within the family.

Though rare, a preauricular fistula can be a sign of certain congenital syndromes and may be associated with genetic conditions, such as:

1. Branchio-oto-renal syndrome (BOR)

This syndrome is associated with ear, kidney, and neck tissue formation disorders and hearing loss caused by mutations in the EYA1, SIX1, or SIX5 genes.

2. Beckwith-Wiedemann syndrome

This syndrome affects various body parts, leading to larger body and organ size. Symptoms include body and tongue enlargement, organs protruding from the navel (omphalocele), and cancers of the kidneys and liver. Patients may also have asymmetrical ear canals.

3. Mandibulofacial dysostosis (Treacher Collins syndrome)

This syndrome involves facial abnormalities, a very small head that doesn't grow proportionately with the rest of the body, developmental disorders, speech and language disorders, and intellectual disabilities. This syndrome is often referred to as Treacher Collins syndrome.

Pediatricians identifying preauricular fistulas in newborns will refer them to an otolaryngologist for further examination. If the pits are infected, the infections are most commonly caused by bacteria called Staphylococcus aureus, followed by Proteus sp., Streptococcus sp., and Peptococcus sp.

Risk factor

One risk factor for preauricular fistula in children is maternal use of hyperthyroid medication, specifically propylthiouracil (PTU), during pregnancy. Early pregnancy use of this medication to treat hyperthyroidism has been linked to congenital facial and neck conditions in newborns, though further research is needed to confirm this association.

Symptoms

Symptoms of a preauricular fistula typically consist of a small hole located in front of the ear. This hole is generally found in front of one ear, but it can also be in front of both ears. Although a preauricular fistula is a congenital disorder and does not pose any harms, it can be a risk if it is associated with a genetic syndrome.

While preauricular fistulas themselves are not dangerous, they can become infected. Symptoms of an infected preauricular fistula include:

• Swelling around the front opening of the ear
• Fluid or pus oozing from the hole
• Redness around the pit
• Fever
• Pain in the area of the pit

Many people are unaware they have a preauricular fistula. Approximately 25% of adults with this condition experience infection symptoms such as fluid discharge from the pit.

Diagnosis

If a preauricular fistula is found in babies or children, the doctor will interview the parents about the child's symptoms, the mother's pregnancy history, and any family history of illness. The doctor will then physically examine the child's head, ears, and neck to determine if the fistula is isolated or part of a genetic syndrome.

Imaging tests such as a CT scan or MRI with contrast may be performed to help identify other conditions, such as cysts or infections. Genetic testing may be recommended for children suspected of having a genetic syndrome. If a genetic syndrome is confirmed, further diagnostic tests will be tailored to that syndrome.

Management

Preauricular fistulas are usually harmless and do not require treatment. While the pit will not close independently, surgery is unnecessary if the fistula does not cause any issues.

Antibiotics

If the fistula infects bacteria, a doctor will prescribe antibiotics to stop bacterial growth. Completing the entire course of prescribed antibiotics is crucial to reducing the risk of antibiotic resistance.

Surgical procedures

If a preauricular fistula repeatedly becomes infected and forms an abscess or pus-filled sac, an incision and drainage procedure may be performed to remove the pus. The doctor might also recommend surgery to close the hole and remove the tract connected to the hole under the skin. 

After surgery, the doctor will provide pain medication and schedule routine checkups. The patient will be instructed on pain management and proper wound care to prevent future infections.

Treatment in children with genetic syndromes

Most children with preauricular fistulas are healthy and lead normal lives. In cases of BOR syndrome, good treatment can prevent kidney failure, allowing patients to live normal lives. 

Although children with Beckwith-Wiedemann syndrome may face a higher risk of death and complications, many can live normal and productive lives. With appropriate treatment, individuals with mandibulofacial dysostosis can have normal intelligence and life expectancy.

Fistula treatment

Preauricular fistulas should be cleaned daily with soap and water, though no specific method exists for cleaning the hole. If an infection occurs, in addition to taking prescribed medication, the following measures can be taken:

• Taking pain relievers
• Applying a warm compress to the ear
• Cleaning the ear area
• Avoiding touching the ears

Complications

Complications of a preauricular fistula include:

Infection

Symptoms of an infection in a preauricular fistula include fever, pain, redness, swelling, and pus discharge. If it is left untreated, this can lead to abscesses and cellulitis.

Cyst

Painless lumps, or cysts, can form in the preauricular pit area, increasing the risk of infection.

Prevention

While this condition cannot be prevented, regular cleaning of the preauricular fistula can help prevent infection. If pus or fluid is discharged from the hole, it is also important to seek medical attention. Delaying treatment could increase the risks of complications such as abscess formation.

When to see a doctor?

A person with two preauricular holes should see an ENT doctor. The doctor can do further tests to check for other conditions related to the preauricular hole. You should also see a doctor for a preauricular fistula if you have recurrent infections, infections that do not respond to antibiotics or medication, and if you have swelling or lumps in your ear.

Looking for more information about other diseases? Click here!