This is an article about cysts in the body. For the ICAO airport code CYST see St. Theresa Point Airport.

A cyst is a closed sac having a distinct membrane and developing abnormally in a cavity or structure of the body. Cysts may occur as a result of a developmental error in the embryo during pregnancy or they may be caused by infections. However, they sometimes arise spontaneously with no apparent cause. Cysts may often be dangerous as they may have negative effects on the nearby tissue. They may contain air, fluids, or semi-solid material.

Cysts may also be a sack that encloses an organism during a dormant period, such as in the case of certain parasites. They protect the parasite from the churning acid of the stomach and once in the intestines, it breaks out.

Cystic fibrosis is an example of a genetic disorder whereby cysts develop in lung tissue and release mucus into the lungs (see Alveoli) reducing lung capacity and causing persistent coughing.

Locations

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Cysts can occur anywhere in the body; however, some of the more common ones are listed here:

• Ganglion cyst (hand/foot joints and tendons)
• Ovarian cyst (ovaries, functional and pathological)
• Pilonidal cyst (skin infection near tailbone)
• Sebaceous cyst (sac below skin)
• Paratubal cyst
• Vocal fold cyst
• Bronchial cyst
• Renal cyst
• Tarlov cyst
• Clindigerous Cyst

Related structures

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Compare a pseudocyst, which is a collection without a distinct membrane.

External links

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Anatomical pathology

Zyste | Kyste | Kisto | Cisti (medicina) | ציסטה | Ciszta | Cyste | Cyste