Riu's stain in the diagnosis of pulmonary cryptococcosis. Introduction of a new diagnostic method.

Pulmonary cryptococcosis is thought to be a rare disease. Clinically, it presents no characteristic symptoms, signs or chest x-ray film findings. Most of the reported cases of pulmonary cryptococcosis were not diagnosed either antemortem or before surgical intervention. A simple diagnostic method, Riu's stain, can be used routinely in bronchoscopic brushing smears, or for needle aspiration cytologic studies, making pulmonary cryptococcosis easy to diagnose.