Bartonella henselae associated uveitis and HLA-B27

Aim-To investigate the frequency of HLA-B27 in patients with presumed Barto nella henselae associated uveitis and to describe the clinical characterist ics of HLA-B27 positive patients with uveitis and presumed ocular bartonell osis (POB). Methods-The diagnosis of POB was considered in 19 patients with unexplained uveitis (except for the HLA-B27 association) and high positive IgG (titre greater than or equal to 1:900) and/or IgM (titre greater than or equal to 1:250) antibodies against B henselae. In addition to B henselae serology an d HLA-B27 typing, all patients underwent an extensive standard diagnostic s creening procedure for uveitis and in all cases the results were within the normal limits. The control group consisted of 25 consecutive patients with panuveitis and negative B henselae serology. Results-HLA-B27 was positive in six of the 19 patients (32%) with POB in co ntrast to the 4% frequency of HLA-B27 in the control group (p=0.03) and 8% prevalence of HLA-B27 in the Dutch population (p=0.003). At the time of pos itive Bartonella serological testing five of six HLA-B27 positive patients with POB had severe posterior segment involvement with papillitis, macular oedema, and vitreitis. The duration of intraocular inflammatory activity wa s more than 6 months in five HLA-B27 positive patients. Although four of th e six HLA-B27 positive patients had previous recurrent attacks of acute ant erior uveitis, the clinical presentation at the time of positive Bartonella serology differed, as illustrated by the involvement of the posterior segm ent and chronic course of the ocular disease. Conclusions-The frequency of HLA-B27 in patients with uveitis and serologic al characteristics of acute infection with B henselae is higher than in the general Dutch population. The findings of this study also suggest a relati on between infection with Bartonella species and HLA-B27.