Identification of amylase crystalloids in cystic lesions of the parotid gland

OBJECTIVE: To identify alpha-amylase crystalloid formations in parotid spec imens obtained by fine needle aspiration. STUDY DESIGN: The study concerned three cases of sialadenitis with crystall oid formation observed between 1993 and 1998. In one of these cases, transm ission electron microscopy, mass spectrometry and measurement of amylase ac tivity were used to characterize the nature of the crystalloids. RESULTS : Light microscopy revealed the same crystalloid structure in all t hree cases. In one case, where the material was saved, a biochemical method made it;possible to reveal high amylase activity, while protein electropho resis and mass spectrometry were used to identify salivary alpha-amylase. CONCLUSION: Crystalloids of salivary alpha-amylase can be identified by May -Grunwald-Giemsa and Papanicolaou stain and can be rapidly confirmed throug h determination of amylase activity.