Primary intranasal encephalocele: a rare cause of bacterial meningitis.

In four patients with bacterial meningitis a primary intranasal encephalocele was found as portal of entry. In two of the cases the malformation had been misdiagnosed as a nasal polyp and operated upon. In two patients a cerebrospinal fluid fistula developed spontaneously at the age of 54 years. None of the patients had associated symptoms indicating the presence of a cleft. Encephaloceles can be readily visualized by computed tomography particularly in coronal sections. The treatment of choice is transcranial surgical repair.