What are the fundamental differences between abscesses and cysts?

Many times, because the symptoms of diseases are too similar or the names are too similar, people often cannot tell which is which. For example, many people cannot tell which is which between abscess and cyst. So what are the differences between the two?

Difference between abscess and cyst

Cyst is a benign disease that can grow on the surface of the human body or in the internal organs. A cyst is a benign cystic mass that grows in an organ in the body. The contents are liquid. Generally speaking, common cysts include "kidney cysts", "liver cysts", "simple ovarian cysts" and "chocolate cysts". Kidney cysts are further divided into simple solitary kidney cysts and polycystic kidneys.

Abscess is a localized accumulation of pus in tissues, organs or body cavities due to necrosis and liquefaction of diseased tissues during acute infection, surrounded by a complete pus wall. The common pathogen is Staphylococcus aureus. Abscess can be caused by acute purulent infection or by the transfer of pathogens from distant primary infection sources through the bloodstream and lymphatic vessels. It is often caused by the necrosis and dissolution of inflamed tissues under the action of toxins or enzymes produced by bacteria, forming a purulent cavity. The exudate, necrotic tissue, purulent cells and bacteria in the cavity together constitute purulent fluid.

The fundamental difference between abscesses and cysts

1. What we usually call abscess refers to the infection of purulent bacteria. After being engulfed by inflammatory cells such as neutrophils and macrophages, the inflammatory cells necrotize and become pus cells. The pus cells rupture and release the lysosomes inside, causing themselves and the surrounding tissues to liquefy and form pus.

2. Special names such as amoebic liver abscess are not abscesses in the true sense. They are formed when amoeba destroys liver tissue. It is mainly infiltrated by acidic granulocytes. It is difficult to see pus cells.

3. For example, in acute pancreatitis, if the exudate is localized but not completely absorbed, it will be wrapped by the surrounding fibrous tissue proliferation. At this time, because the cyst wall does not contain epithelial cells, it is called a pseudocyst.

4. The cysts we usually refer to are liver cysts, kidney cysts, pancreatic cysts, etc. seen under B-ultrasound. At this time, the cyst wall contains epithelial cells that can secrete cystic fluid, and the cyst will slowly increase in size.

5. Ovarian chocolate cysts, as described by gynecologists, are caused by ovarian endometriosis, which causes bleeding during each menstrual period and is wrapped by surrounding tissues. The cyst fluid is chocolate-colored due to old blood.