1 Answer

Kidney lesions are areas of anomalous tissue in or on the kidneys. Lesions can be a cause for concern in some patients depending on their cause and precise location, along with how fast they grow. Some people have lesions on their kidneys and are unaware of it, while others may develop symptoms such as bloody urine, back pain, and kidney obstruction as a result of impairments in renal function caused by the lesion or lesions.

A number of different things can cause a lesion. Lesions are injuries which are characterized by the presence of tissue which does not belong or which grows abnormally. Cancers can cause lesions as can infections and trauma. Like other lesions, kidney lesions are classified as either benign or malignant. A malignant lesion is cancerous and requires treatment. A benign lesion is not cancerous, but may still cause medical complications which lead to treatment.

One reason to develop kidney lesions is because of kidney cancer, in which case a mass may be visible in the kidneys if a patient is given an ultrasound. Another reason can be chronic infections which lead to scarring and damage. This in turn can obstruct the drainage from the kidneys or interfere with kidney function in other ways. Scarring can also be caused by surgery, inflammation, and other processes which involve the kidneys.

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