Question
There is a small opening on the earlobe, which often becomes red, swollen, and itchy. Examination reveals the presence of a preauricular sinus tract. What are the causes of preauricular sinus tract?
Answer
Congenital preauricular sinus tract is a common otolaryngological condition. It is caused by improper fusion of the first and second branchial archs’ tubercle-like nodules or incomplete closure of the first branchial cleft during embryogenesis. The sinus tract is a blind tube that can have branches and curves, with its external opening usually located above the antihelix of the earlobe. The lumen is lined with stratified squamous epithelium, containing scale-like particles. Compression around the sinus opening may occasionally result in a small amount of sticky sebaceous material being exuded. Once infected, it becomes red, swollen, painful, and may become purulent, often recurring. This condition is an incomplete dominant genetic disease with an autosomal dominant inheritance pattern. The first branchial cleft is a remnant caused by incomplete fusion during embryogenesis. The sinus opening is usually located on the antihelix of the ear. The sinus tract can branch and its walls are lined with squamous epithelium. The lumen contains desquamated epithelial cells and keratinous material. Infection can lead to smelly secretions, and repeated infections can form cysts or abscesses. Guidelines: If there is no history of infection, there is no need for treatment for this condition. During acute infection, systemic antibiotics should be used to control inflammation. For those who have formed abscesses, incision and drainage should be performed first. For those with a history of infection, sinus tract resection can be performed after infection control. It is recommended to have a light diet, consisting of lean meat or