Clinical manifestations associated with high titer of anti-streptolysin O in Behcet's disease.

To evaluate the association of chronic infection with clinical features of Behcet's disease (BD), we studied epidemiological and clinical features of 149 patients with only aphthous ulcer and 294 patients with BD. The incidence of chronic infection history was compared between both groups with age- and sex-matching and clinical manifestations of BD associated with high anti-streptolysin O (ASO) titer were investigated. BD patients had more common history of tonsillitis and dental caries than aphthous ulcer patients (P = 0.002 and P = 0.043, respectively). BD patients with persistently high anti-streptolysin O titers had more frequent history of tonsillitis (P = 0.001, odds ratio [OR] = 2.99, 95% confidence interval [CI] 1.53-5.82) and erythema nodosum (EN)-like lesions (P = 0.001, OR = 3.02, 95% CI 1.54-5.93) and fewer history of genital ulcer (P = 0.027, OR = 0.21, 95% CI 0.05-0.84) than BD patients with normal anti-streptolysin O titer. Our results suggest persistently high ASO titers in BD patients could indicate that streptococcal infections such as tonsillitis are related to BD symptoms such as EN-like lesions. In these patients, ASO titer can be used in the evaluation of BD disease activity and antibiotic treatments might be effective to control the symptoms of BD.