Standardized thionin-eosin stain in bronchial cytology. A substitute for hematoxylin-eosin Y staining.

A standardized thionin-eosinic acid stain was developed as a quick and highly reproducible staining method for bronchial cytology. Bronchial smears and paraffin-embedded sputum samples were stained with thionin-eosin and with the conventional hematoxylin-eosin Y. Spectral absorption characteristics and staining intensity of thionin-eosin-stained cells were investigated by means of cytophotometry. The staining pattern of thionin-eosin is very close to that of the hematoxylin-eosin stain; the contrast between nucleus and cytoplasm is significantly higher for thionin-eosin. Thionin-eosin can be used for "dye-fixation" of cytologic smears and tissue imprints. Blueing and differentiation (as for hematoxylin-eosin) is not required for thionin-eosin; thus, fixation and staining can be performed within two minutes. The spectral absorption characteristics of thionin-eosin allow reliable automated cytophotometric discrimination of cell nuclei and cytoplasm. The standardized thionin-eosin stain is recommended as a substitute for the hematoxylin and eosin stain in bronchial cytology.