Late-Onset Langerhans Cell Histiocytosis Presenting with Seizures and Bilateral Temporal Involvement.

Langerhans cell histiocytosis is known as a rare childhood disease. In this case, we wanted to share our patient's experience whose first symptom was an epileptic seizure, which attracted attention at an advanced age and revealed bilateral temporal lobe involvement. Our case was a 51-year-old male, who had been having seizures with focal onset, autonomic characteristics, impaired awareness, and occasionally secondary generalized seizures for 5 years, was admitted due to an increase in the frequency of seizures over the past 6 months. The patient was diagnosed with Langerhans cell histiocytosis as a result of pathological examination of the bronchoalveolar lavage. In cranial magnetic resonance imaging, bilateral temporal regions are hyperintense on T2 and Fluid Attenuated Inversion Recovery (FLAIR)-weighted images and hypointense and partially enhanced contrast on T1-weighted images. Additionally, central involvement of Langerhans cell histiocytosis was supported by hyperintensity in the optic chiasm, pituitary gland, and around the third ventricle on T2 and FLAIR-weighted images. Elect roenc ephal ograp hy showed sharp slow wave activity in the left anterior temporal region. After controlling our patient's seizures, we referred him to the oncology and hematology departments to regulate his treatment for primary disease. It should be noted that in late-onset Langerhans cell histiocytosis, epileptic seizures may occur as the first symptom rarely, due to secondary involvement of the central nervous system. [ABSTRACT FROM AUTHOR]