Any of several types of cysts in the kidneys. Some are present at birth; others are caused by tubular obstruction. Large cysts can cause backaches and a dragging sensation. Multiple cysts occur as a result of various disorders, including kidney vascular diseases, lymphatic vessel blockage, congenital diseases, and tapeworm infestation. The most serious is medullary cystic disease, which has no warning symptoms but causes anemia, low blood sodium levels, and uremia. The kidneys become shrunken, grainy, and scarred. Cysts should usually be checked surgically to rule out cancer. Seealso urogenital malformation.
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Enclosed sac within body tissues. It has a distinct membrane and generally contains liquid. Most cysts are benign, but several kinds may be malignant or precancerous. Benign cysts often press on nearby organs and require removal. Formed by overproduction of epithelium (surface tissue of anatomical structures), cysts may become detached from surrounding structures and move freely. They can contain natural secretions, abnormal breakdown products, or, in infections, bacteria, larval parasites, and microbial products. Some organs, including the kidney, liver, and breast, can become filled with cysts as a result of cystic diseases that may be dangerous or may hide more serious diseases. Seealso tumour.
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A cyst is a closed sac having a distinct membrane and division on the nearby tissue. It may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, the cyst could go away by itself or will have to be removed using surgery.
A syrinx in the spinal cord or brainstem is sometimes inaccurately referred to as a cyst.