Skin prick test with self saliva as a diagnostic test for Behçet’s disease

Aim of the work: To determine the reliability of skin prick test using self-saliva, which mostly contains streptococci, for in vivo diagnosis of Behçet’s disease (BD) in comparison to the usual pathergy test. Patients and methods: Thirty patients diagnosed with BD of matched age and sex to 30 with undiagnosed recurrent aphthous stomatitis (RAS) and 30 healthy controls were enrolled into this study. Skin pathergy test and skin test with self saliva before and after being filtered with a micro filter paper was performed on forearm of all subjects participated in this study. The skin reaction was observed at 48 h after pricking. Results: The mean age of the BD patients was 30.1 ± 7.1 years and were 22 males and 8 females (M:F 2.75:1). The mean disease duration of the BD patients was 10.13 ± 7.47 months. In BD patients, mucocutaneous and ocular manifestations were significantly increased. Positive tests were more frequent in BD patients. SPT-NSS showed a significantly higher accuracy more than pathergy and SPT-FSS in discriminating BD from non BD and from RAS. Diagnostic accuracy of skin prick test with neat self saliva (SPT–NSS) in discriminating BD from non BD was significant with sensitivity 80%, specificity 100% while the ability of the test to discriminate between BD and RAS was 83% sensitivity and 63% Specificity more than pathergy test and skin prick test with filtered saliva respectively. Conclusion: Skin prick test with neat self-saliva could be considered as a simple, cost accessible and accurate diagnostic test for BD.