In subgroup A.2 with syringomyelia and otitis, the mean IL-31 level in serum tended to be higher compared to subgroups A.1 with syringomyelia only and A.3 with syringomyelia and other neurological diseases (Table 1), although this difference was not significant (p = .2263, Fig. 2). This evidence concerns the gene IL31 and ear infection.