Charcot-Leyden Crystals: Pathology and Diagnostic Utility

Eosinophilia is associated with several diseases of the upper respiratory tract. The predominance of eosinophils in nasal tissue, secretions, and lavage fluid has been used as an aid in the diagnosis of allergic rhinitis. Charcot-Leyden ctystals, considered to be a morphologic hallmark of eosinophil-related disease, are often also found in inflamed nasal tissue and paranasal sinus contents of patients with allergic rhinitis. These bipyramidal-shaped crystals are composed of the enzyme lysolecithin acylhydrolase, one of several eosinophilic proteins that damage respiratory epithelium and contribute to the pathology of allergy in the upper respiratory tract.