BACKGROUND: Multiple evanescent white dot syndrome (MEWDS) is an acquired chorioretinal disorder of unknown etiology. We investigated the possibility that MEWDS might be related to a specific HLA subtyping. METHODS/RESULTS: Blood was obtained from nine patients affected by MEWDS. HLA-B51 was found in four of these nine patients with MEWDS. CONCLUSION: There was a 3.7-fold increased frequency of HLA-B51 in patients affected by MEWDS (relative risk 5.86). MEWDS might then be related to the presence of a specific HLA subtype, HLA-B51. However, due to the small sample size, our results need to be confirmed by further testing.