Asthma: cytologic examination of sputum after an asthmatic attack shows eosinophils, Charcot-Leyden crystals (orange, elongated, rhomboid crystals formed by degranulation of eosinophils) and Curshmann's spirals (dark staining core surrounded by lighter mucous). Biopsy is rarely done. In patients dying of status asthmatics the lungs are over-expanded and small airways are occluded by mucoid secretions. There is a variable amount of bronchiolar inflammation, including eosinophilic infiltrates. Mucus glands are hyperplastic with hyperplasia of bronchial and bronchiolar smooth muscle

Charcot leyden crystals