Post-auricular teratoma in an HIV-exposed newborn.

Teratomas in the neonatal age group are mostly benign at first, and the common site is the sacrococcygeal region. They are rarely associated with HIV infection. We report a case of an HIV-exposed newborn with a congenital teratoma at the post-auricular site who developed an infection. Early intervention by total surgical resection will prevent complications such as infections and malignant transformation. A term baby was delivered spontaneously by an HIV-positive mother who was on her regular medications. Prenatal ultrasound carried out in the third trimester showed a cyst swelling on the right post-auricular region. Radiological imaging and the histopathological result revealed a congenital teratoma. A wide major excision with preservation of the facial nerve was performed at the age of 8 weeks. Post-auricular teratomas are the rarest anatomical location and the prevalence of malignant transformation from benign is very low. If left untreated, this tumour is associated with high mortality and malignant transformation rates. An early complete surgical excision allows a good result with a low risk of complications and recurrence.