Skull base Langerhans cell histiocytosis presenting as persistent ear discharge with granulation-like tissue in the external ear canal.

Langerhans cell histiocytosis (LCH) is a neoplastic disease characterised by the deposition of granulomatous lesions in various tissues in the body. LCH of the lateral skull base commonly presents with scalp lesions, post-auricular lesions, otalgia and persistent ear infections. A toddler was brought to the ENT clinic with persistent left ear canal granulation tissue and bloody and malodorous discharge. After failed medical treatment with antibiotic and steroid topical drops. The ear was examined under general anaesthesia. Large friable granulation tissue was seen obstructing the external auditory canal extending to the tympanic membrane. Histological examination of the surgical specimen revealed CDa-1-positive cells, diagnostic of LCH. There were widespread enhancing tissues throughout the skull base bilaterally on CT. She was diagnosed with multiple bone LCH, enrolled in the LCH-IV trial and started on chemotherapy. This case highlights the importance of histological and radiological diagnosis of granulation tissue after failed medical treatment.