"In patients diagnosed with HLA-B27-related anterior uveitis (cohort HLA-B27+1) and with HLA-B27- non related anterior uveitis (cohort HLA-B27-) no significant differences were found regarding clinical characteristics between both cohorts with the exception of a higher frequency of recurrences in cohort HLA-B27+ and a higher frequency of chronic uveitis in cohort HLA-B27-."xsd:string