Use of ultrasound biomicroscopy, indocyanine green angiography and HLA-B51 testing as adjunct methods in the appraisal of Behçet's uveitis.

Abstract

Behçet's uveitis is not common in western Europe and the disease presentation is less obvious than in "endemic" countries such as Turkey and Japan. This makes the diagnosis more difficult. Early diagnosis is important, as the prognosis is better if therapy is started early. New methods such as ultrasound biomicroscopy (UBM) and indocyanine green angiography (ICGA) can improve the characterisation and diagnosis of uveitis. Our purpose was to present our experience with these new methods as well as HLA-B51 testing in the appraisal of patients with Behçet's uveitis. Patients seen by the authors between 1997 and 2001 with Behçet's uveitis or suspected Behçet's uveitis and who underwent ICG angiography or UBM were included. Symptoms and signs, results of laboratory work-up including HLA-B51 antigen testing and the delay to diagnosis, were analysed. Fluorescein and ICG angiography and UBM testing were performed according to standard protocols used for uveitis patients and their contribution towards diagnosis and management were analysed. Uveitis was non granulomatous in all patients. Fluorescein angiography showed moderate to severe diffuse retinal vasculitis compatible with Behçet's uveitis in all cases. HLA-B51 testing was positive in 5 of 7 tested cases, being useful to orient the diagnosis. UBM contributed to the diagnosis in all five tested cases, being the determining element in 3 patients. It allowed redirection of the diagnosis from pars planitis to Behçet's in 2 patients with poorly transparent media because it failed to show the typical pars planitis deposits. In a case originally diagnosed as Behçet's it allowed correction of the diagnosis to pars planitis because of the presence of the typical UBM pars plana depositis. ICG angiography allowed detection of choroidal vasculitis in all five tested cases. In Behçet's patients who did not present with a full-blown clinical picture, as they are often seen in non-endemic areas, UBM examination and HLA-B51 testing were valuable additional diagnostic elements helping to redirect the diagnosis correctly and to reduce the diagnostic delay in these patients. The hitherto unknown choroidal vasculitis shown by ICG angiography in all five investigated patients indicates that choroidal involvement probably occurs in most newly diagnosed Behçet's patients.