Serous sputum

Serous sputum is a physiological secretion formed in the upper respiratory tract (nasopharynx, oropharynx) and released from the nasal cavity along with nasal secretions, and occasionally from the larynx. The consistency of serous discharge from the oral cavity is usually less dense than sputum, which is due to the peculiarities of the outflow of fluid from the paranasal sinuses. The sputum contains no signs of inflammation, epithelial cells, erythrocytes, or cellular debris. The density of serous sputum ranges from 0.87-0.95 g/l. The color of serous discharge from the oropharynx is transparent and grayish. Exudates of various origins may also appear in the perineum and vulva. The volume of serous sputum varies from person to person. There are several values ​​for the norm of discharge from the respiratory system: 0.5 ml per day; 20 ml per day; approximately 50 ml in 4 hours. These figures are based on a healthy adult without any disease and not smoking. If the sputum looks sterile