Summary: Langerhans’ cell histiocytosis (formerly called Histiocytosis X) is a rare hematological disease, that often affects head and neck. Its localized bone form was formerly called the Eosinophilic granuloma. Authors present two cases of Eosinophilic granuloma of the temporal bone and discuss the history, current nomenclature, histopathological and clinical characteristics, diagnosis and therapy of this disease. In case report No. 1 authors present 5.5 years old patient afflicted with Langerhans’ cell histiocytosis, which imitated otitis media acuta protrahens polyposa. Patient was treated for two months with antibiotics and paracentesis, she was afebril, with low level of inflamation markers (Leu 11,7...7,8, CRP 0,1). Because of not improving of local findings, CT was indicated. This showed osteolysis of ventrolateral part of the right temporal bone. With regard to suspition of Langerhans’ cell histiocytosis, atticoantrotomia was done. Histopatologist confirmed the diagnosis of Langerhans’ cell histhocytosis. X-ray of long bones and lungs and scintigraphy of whole skeleton was negative. Patient has no subjective problems; she has normal hearing. Case report No. 2 refer about 3 years old patient with 5 cm soft extuberance of squama of the left temporal bone. He was without pain, with low level of inflammatory markers. CT examination showed 2 cm wide destruction of bone. Tumor was removed, histopatology confirmed the diagnosis of Langerhans’ cell histiocytosis. Additional examinations confirm monoostitic form of disease.

        Key words: Langerhans’ cell histiocytosis, Eosinophilic granuloma, temporal bone.