Hair in the wrong place: A rare case of pilonidal sinus in preauricular sinus tract

Introduction: The preauricular sinus is a congenital abnormality which was initially identified by Van Heusinger in 1864. Preauricular sinus development is strongly related to the development of auricle in the sixth week of pregnancy. Preauricular sinus can be inherited or are sporadic. Most cases are sporadic and over half of all cases are unilateral. Bilateral cases are more frequent in inherited cases. Case Report: A 10 year old boy was brought with complaints of discharge from left pre auricular region on and off since birth. History of frequent episodes of discharge from left pre auricular region about 2-3 episodes per year. Local examination showed preauricular sinus tract at the root of helix on both sides. There was no discharge,no warmth, no tenderness. The child underwent necessary investigations and pre aneasthetic fitness was obtained. Pre auricular sinus tract excision on left side under general anasthesia was done. Multiple sinus tracts were excised and sent for histopathological examination which showed evidence of pilonidal sinus. There was presence of sinus tract line by epidermis, lumen filled with keratin and hair shafts. The child was brought for follow up on postoperative day 10, the sutured site was found to be healthy. Suture removal was done and the wound was healing well. The child is on regular follow up and has shown no signs of any recurrence. Discussion: The only definite treatment of recurrent infective sinuses is complete excision of the sinus tract. In our case, supra aural elliptical incision was placed and all visible sinus tracts were cleared and sent for histopathological analysis. When these sinuses get infected, most frequent cause being with gram-positive bacteria, the exudates should be sent for culture, and the appropriate antibiotics should be administered. The temporalis fascia, the cartilage of the helix, and the auditory canal are identified using the supra-auricular approach. An en bloc excision of the sinus is then carried out. Pilonidal sinus is a difficult condition that causes suffering and embarrassment to its victims. Despite it being rare and atypical, pilonidal sinus could also occur in the auricular region. Although pilonidal sinus has been reported in a number of uncommon areas of the body besides the sacrococcygeal region, this is the second case of pilonidal sinus that we are aware of in the preauricular region that is reported in literature. Conclusion: Thus we present a very rare case of pilonidal sinus in pre auricular region. Only two cases have been reported till date in literature and our case is the second one to be reported in the pre auricular region.