recurrent aseptic meningitis

Recurrent aseptic meningitis refers to a meningitis that follows a relapsing course. During episodes, fever, nuchal rigidity, and other meningeal irritation signs occur, while cerebrospinal fluid examination mainly shows lymphocytic pleocytosis and mildly elevated protein, generally resolving spontaneously and rapidly within a few days. During the interictal period, symptoms completely disappear, and cerebrospinal fluid fully returns to normal. The course is benign and may recur for up to several years. This condition was first described by Mollaret (1944). At that time, since Gram staining and bacterial culture of cerebrospinal fluid failed to identify a pathogen, it was termed aseptic meningitis or "Mollaret meningitis." In a 1952 report, Mollaret speculated that it was related to viral infection. In 2000, DeBiasi and Tyler classified the etiologies of recurrent aseptic meningitis into nine categories and recommended that the term Mollaret meningitis be reserved specifically for recurrent aseptic meningitis in which the cause cannot be identified despite appropriate diagnostic measures.