THE INFLUENCE OF PATHERGY TEST ON THE ACCURACY OF DIFFERENT DIAGNOSIS CRITERIA FOR BEHCET’S DISEASE.


Abstract: Introduction: Pathergy test (PAT) is used in the majority of diagnosis criteria set for Behcet’s Disease (BD). The modality of performing it (needle gauge, sharpness of the tip, direction of skin penetration, with or without a product injection), the delay to read the result (24 or 48 hours), and the cut-off line for positive test is not standardized. Therefore the results differ from one center to another, introducing a great bias in the classification. The aim of this study was to analyze the sensitivity, the specificity, and the accuracy of the following criteria without the use of PAT: Dilsen (D), Japan revised (J), International (I), and the Classification Tree (CT). Materials and Methods: The 5 upper-mentioned criteria were tested against 4717 BD patients and 2407 control patients with and without the PAT result. Conclusion: The International criteria lost 11% while the Japan and the Classification Tree lost each 5%. The latter are more suitable for the diagnosis and classification in the absence of PAT. The accuracy was significantly higher for the Classification Tree (92%).