Beyond the typical: a postauricular variant of preauricular sinus in a child

The preauricular sinus, a congenital anomaly commonly situated anterior to the tragus, can present in a posterior location, mimicking other postauricular pathologies. This report describes a 5-year-old girl with a two-year history of recurrent left postauricular swelling, initially treated as a postauricular abscess. Examination revealed a sinus pit over the antitragus and a healed scar in the posterior auricular sulcus. Surgical excision was performed under general anaesthesia using a unidirectional approach, revealing a posteriorly directed sinus tract towards the postauricular region. Complete removal of the sinus tract and sac, including a segment of the auricular cartilage. Histopathological examination confirmed the diagnosis of a preauricular sinus. This case highlights the need to include variant-type preauricular sinuses in the differential diagnosis of recurrent postauricular swelling, with surgical excision as the definitive therapeutic approach. An accurate diagnosis with a detailed history and clinical examination is critical for effective management.