The cytologic examination of the nasal discharge is, in my judgment, an important procedure with every patient with a nasal lesion. I should feel that my examination was incomplete if this had not been done. The cytologic examination of the discharge from the ear, while not so important, has a distinct advantage. If on examination of the nasal discharge it is found to be almost all mucus with very few cells, that means one thing; if the fluid contains practically no mucus, as in cerebrospinal rhinorrhea, that would suggest another thing. The presence of many polymorphonuclear neutrophils in the discharge taken from the neighborhood of the ostium of the sinus indicates infection. Even to a layman the presence of pus cells will mean something. When red blood cells are found they have clinical significance. The presence of degenerated epithelial cells without any blood cells is of decided clinical significance.
DEAN LW. LABORATORY INVESTIGATIONS AS AIDS IN OTOLARYNGOLOGIC DIAGNOSES. JAMA. 1932;99(7):542-546. doi:10.1001/jama.1932.02740590022006