Background: Although papulopustular lesions are one of the diagnostic criteria for Behçet's disease, controversy exists as to the nature of these lesions. Specific vessel-based papulopustular lesions as well as nonspecific follicular lesions may be seen in patients with Behçet's disease. Some authors suggest that papulopustular lesions should be considered a positive criterion only if they exhibit a vessel-based neutrophilic reaction.
Objective: [corrected] To determine whether specific vessel-based papulopustular lesions can be differentiated clinically from nonspecific follicular lesions in patients with Behçet's disease.
Methods: Twenty-three papulopustular lesions in 20 patients with Behçet's disease were initially examined clinically by two dermatologists blind to each other's diagnosis. Biopsies taken from these lesions were examined by a pathologist unaware of the patient data.
Results: Leukocytoclastic vasculitis or perivascular infiltration was observed in 10 lesions, perifollicular and perivascular infiltration was noted in nine lesions, and perifollicular inflammation was seen in four biopsy specimens. Most of the lesions interpreted clinically as specific papulopustular lesions of Behçet's disease had predominantly perivascular infiltration or leukocytoclastic vasculitis; however, three papulopustular lesions evaluated by both observers as specific papulopustular lesions had only perifollicular inflammation, and one lesion diagnosed clinically as a nonspecific follicular eruption revealed perivascular neutrophilic reaction. Interobserver variance was noted in three papulopustular lesions.
Conclusions: Clinical examination may not be sufficient to predict the dermatopathologic pattern in all lesions. Papulopustular lesions with no specific clinical and histopathologic features may create problems in the diagnosis of Behçet's disease.