Background: Behcet's disease (BD) is known to vary in severity and manifestations in different populations.
Objective: In an attempt to sort out genetic and environmental influences on disease expression, we carried out a study to assess the clinical features of BD in the adult Druze and Arab populations in north Israel, comparing 2 disparate ethnic groups of similar genetic background inhabiting the same geographic region.
Methods: We compared 23 Druze and 30 Arab patients with BD. All patients fulfilled the classification criteria of the International Study Group for BD.
Results: Manifestations were similar in 2 groups. The most frequent BD manifestations among the Druzes were recurrent oral aphthae (100%) and genital aphthae (61%) versus 100% and 53% in Arab patients, followed by inflammatory ocular involvement, 65% versus 53%, respectively. Arthritis was noted in 39% of Druze, with 27% in Arabs. Anterior uveitis occurred in 9 Druze patients (48%) and panuveitis in 4, with no case of blindness when compared with 30% with anterior uveitis, 4 with panuveitis, and 4 cases of blindness (P < 0.04) among the Arabs. One Druze BD patient had deep vein thrombosis versus 8 Arab patients (P < 0.017). No pulmonary embolism, aortic aneurysm, nor valvular involvement was documented in the Druze versus 1 case of each in Arabs. No case of neuro-Behcet was reported in Druzes versus 6 cases of neuro-Behcet among Arabs (P < 0.023). The severity score was 4.0 (SD, 1.2) in Druze and 5.8 (SD, 1.9) in Arabs (P = 0.0004). The prevalence of HLA B51 did not differ significantly between the groups.
Conclusion: Druze BD patients in Israel have a milder disease than do Arabs, similar to observations in familial Mediterranean fever. Druze BD patients had significantly less severe ocular disease and neurologic manifestations. Our results suggest an ethnic influence on expression of BD not related to HLA B 51.