Green pus isn't always a sign of something serious, but it does indicate the presence of certain bacteria or immune responses. The color comes from two primary sources:
1. Myeloperoxidase
- What it is: Myeloperoxidase is an antibacterial protein produced by certain types of white blood cells (specifically neutrophils). It's part of your body's immune response to fight infection.
- Why it makes pus green: This protein has an intensely green color, and its presence in high concentrations within pus can contribute to a greenish hue. Multiple sources, including Wikipedia and University Health News, confirm this.
2. Bacterial Pigments
- Specific Bacteria: Certain bacteria, such as Pseudomonas aeruginosa, produce pigments that are green. Pyocyanin, a pigment produced by Pseudomonas aeruginosa, is a prime example.
- Infections: Infections caused by these bacteria can result in green pus due to the release of these pigments into the infected area.
In short: The green color of pus is often due to the presence of myeloperoxidase, an enzyme released by your immune system, or the pigments produced by specific bacteria like Pseudomonas aeruginosa. The color itself doesn't indicate the severity of the infection, but it does signal the presence of these specific components. The presence of a foul odor alongside the green color, however, can be a further indicator of a bacterial infection.
Examples:
- A wound infected with Pseudomonas aeruginosa might produce green pus due to pyocyanin.
- An infection where the body's immune response is strong may show green pus due to myeloperoxidase.
