Pilonidal sinus—also called a pilonidal cyst—is a skin infection that occurs in or around the crease of your buttocks. This condition happens when hair, skin cells, and dirt clog a hair ...

Sometimes nasal discharge can be a sign of a sinus infection caused by bacteria. While the color of the mucus does not distinguish between a viral or a bacterial infection, several other signs ...

In February 1 Journal of Clinical Investigation, Dieter Worlitzsch and colleagues from University of Tübingen, Germany show that airway mucus hypoxia contributes to the early pathogenesis of P.