Preauricular sinus formed due to Mal union of 1st&2nd arch hillocks. They present antenatal or during birth and any age during development. Medical Care Infectious agents identified included Staphylococcus epidermidis (31%), Staphylococcus aureus (31%), Streptococcus viridans (15%), Peptococcus species (15%), and Proteus species (8%). Once a patient acquires infection of the sinus, he or she must receive systemic antibiotics. If an abscess is present, it must be incised and drained, and the exudate should be sent for Gram staining and culturing to ensure proper antibiotic coverage. Surgical Care Once infection occurs, the likelihood of recurrent acute exacerbations is high, and the sinus tract should be surgically removed. Surgery should take place once the infection has been treated with antibiotics and the inflammation has had time to subside. The recurrence rate after surgery is 13-42% in smaller studies and 21% in one large study. Most postoperative recurrences occur because of incomplete removal of the sinus tract. So use antibiotics like amoxicillin clavulinicacid 625 tid, send Pus culture and change antibiotic, if no response go for sinus excision.