[Treatment outcome of patients with cranial base lesions of unknown etiology: focusing on infectious cases with multiple cranial nerve disorders].

Involvement of cranial nerves caused by cranial base lesions manifests diverse symptoms according to the localization of lesions. These localization-related symptoms are classified into syndromes such as orbital apex syndrome, cavernous sinus syndrome, and jugular foramen syndrome. Since the lesions may have various etiologies including infection, inflammation and tumor, etiological diagnosis should be performed simultaneously if possible. However, previous reports have described poor and/or fatal outcome following inappropriate treatment mainly due to difficulties in making a definitive pathological diagnosis. Nineteen patients with multiple cranial nerve involvement caused by skull base lesions were enrolled over the past 12 years. The patients were divided into an "infectious" group (n=11) and a "noninfectious" group (n=8) based on the final diagnosis. Chi-square analysis was conducted to examine the sensitivity and specificity of various factors including patient characteristics, clinical course and treatment response in infectious and noninfectious groups. Consequently, we identified some patients with good outcome irrespective of infectious or noninfectious etiology, even though a pathological diagnosis was not reached before the initial treatment. These patients with good outcome consistently received antifungal therapy in the early stage if infectious etiologies were suspected. We recommend conducting diagnostic therapy with antifungal drugs in patients with skull base lesions of unknown origin although infection cannot be excluded, when a pathological diagnosis is difficult due to various patient conditions.