[Langerhans cell histiocytosis: petrosal remodelling after chemotherapy--case report and review of the literature].

We report the case of a child presented by her parents to the ENT outpatient service for swelling of the right temporal bone. The child had a history of recurrent bilateral inflammation of the middle ear. Tympanometry revealed a reduced compliance. Due to conductive hearing loss it was impossible to measure otoacustic emissions. Otherwise a normal ENT status was found. Imaging (MRI/CT) demonstrated bitemporal soft-tissue changes with extensive osseous destruction, but no typical imaging signs of an inflammatory, dysplastic or expansive process. The tentative diagnosis of Langerhans' cell histiocytosis (LCH) made on the basis of the clinical and imaging findings was confirmed by biopsy. After exclusion of disseminated LCH, chemotherapy was initiated, and the child underwent follow-up imaging after 3 months. CT showed clear signs of bitemporal reossification. The case reported here illustrates the problems encountered in diagnosing LCH which may present with unspecific clinical symptoms despite advanced osseous destruction. ENT specialists should be familiar with this very heterogeneous entity and think of LCH especially in children presenting with therapy-refractory otitis media, otitis externa, or mastoiditis in order to ensure a timely diagnosis and to thus improve the chances of successful therapy. Imaging modalities (CT, MRI) have a role in the early diagnosis and follow-up of this disorder.