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RATIONALE The Sarcoidosis Diagnostic Score (SDS) has been established to quantitate the clinical features consistent with sarcoidosis in a monocentric study. OBJECTIVES We aimed to confirm the diagnostic value of SDS in a large, multicontinental study and to assess the utility of SDS in differentiating sarcoidosis from alternative diagnosis including infectious and non-infectious granulomatous diseases. METHODS We included patients with biopsy-confirmed sarcoidosis at nine centers across the world. Patients without sarcoidosis seen at the same sites served as control patients. Using a modified World Association of Sarcoidosis and Other Granulomatous Disorders organ assessment instrument, we scored all patients for presence of granuloma on biopsy, highly probable symptoms, and least probable symptoms for each area. Two sarcoidosis scores were generated: SDS Biopsy (with biopsy) and SDS Clinical (without biopsy). SDS Clinical and Biopsy were calculated for all patients. We calculated and compared the Area Under Curve (AUC) for SDS Clinical and Biopsy according to different diagnosis scenarios. RESULTS A total of 1041 patients with sarcoidosis and 1035 without sarcoidosis were included. SDS Clinical (AUC=0.888, 95%CI: 0.874-0.902) and SDS Biopsy (AUC=0.979, 95%CI: 0.973-0.985) according to AUC were good to excellent for differentiating sarcoidosis from alternative diagnosis. SDS Clinical was less discriminatory in male (p=0.01) and in "high tuberculosis prevalence" centers (p<0.001). However, SDS Clinical (AUC=0.684, 95%CI: 0.602-0.766) and SDS Biopsy (AUC=0.754, 95%CI: 0.673-0.835) were not sufficiently discriminative for non-infectious granulomatous diseases, but both SDS could differentiate sarcoidosis from infectious granulomatous diseases. Algorithms were proposed for the SDS Clinical and SDS Biopsy to assist the clinician in the diagnostic process, and proposed cut-off values for the SDS Clinical and SDS Biopsy allowing the diagnosis of sarcoidosis to be safely confirmed or rejected in most cases except non-infectious granulomatous disease. CONCLUSIONS This multicontinental study confirms that both SDS Clinical and SDS Biopsy have good to excellent performance to discriminate sarcoidosis from alternative diagnoses. Differences in the AUC were seen for "high tuberculosis prevalence" versus "low tuberculosis prevalence" centers and males versus females. Both SDSs had good discriminatory function for infectious granulomatous disease but failed in case of non-infectious granulomatous disease such as berylliosis.