OBJECTIVE: To assess the value of the parotid biopsy as a diagnostic tool for primary Sjögren's syndrome (pSS), and to compare the parotid biopsy and the labial biopsy with regard to diagnostic value and biopsy-related morbidity.
METHODS: In 15 consecutive patients with pSS and 20 controls, the parotid biopsy was assessed as a diagnostic tool based on the presence of lymphocytic foci, benign lymphoepithelial lesions and lymphoid follicles. These new histological criteria were compared with established diagnostic criteria for the labial biopsy in 35 consecutive patients suspected for pSS who underwent simultaneous biopsies from both sites. In addition, both biopsies were compared for morbidity.
RESULTS: The first analysis revealed a focus score of >or=1 or lymphocytic infiltrates (not fulfilling the criterion of a focus score of 1) combined with benign lymphoepithelial lesions as diagnostic criteria for pSS. When comparing the parotid biopsy with the labial biopsy sensitivity and specificity were comparable (sensitivity 78%, specificity 86%). Level of pain was comparable and no loss of motor function was observed. No permanent sensory loss was observed after parotid biopsy, while labial biopsy led to permanent sensory loss in 6% of the patients. Malignant lymphoma was detected in one parotid biopsy by chance, without involvement of the labial salivary gland.
CONCLUSION: A parotid biopsy has a diagnostic potential comparable with that of a labial biopsy in the diagnosis of pSS, and may be associated with less morbidity.