Definition
A renal abscess is an encapsulated accumulation of pus between the kidney surface and the so-called Gerota fascia. It is a kind of skin that surrounds the kidney. This type of renal abscess is also called perinephritic abscess because it is located around the kidney.
From this perinephritic abscess we distinguish the paranephritic abscess. It usually develops at the bottom of a perinephritic abscess. The pus breaks through the renal capsule and is located in the so-called retroperitoneum, the space behind the kidney.
Causes
There are several causes for the development of a kidney abscess. Particularly at risk for the development of a kidney abscess are people with a weakened immune system, drug addicts, patients in intensive care units or on dialysis, and people with heart valve defects and bacterial infections of the heart valves. All these things increase the risk of bacteria spreading in various organs, including the kidneys.
- An important possible cause of renal abscesses are renal infections. Such an infection is also known as inflammation of the renal pelvis (pyelonephritis). This is a bacterial, purulent infection, often caused by insufficiently treated cystitis.
The pathogens can thus ascend the ureter and co-infect the renal pelvis.
- Urinary stasis, i.e. a reduced outflow of urine, in the renal pelvis can also lead to infections and ultimately to abscesses. Urinary congestion can have many causes, such as obstruction of the flow of urine in the ureters due to tumors, or even paralysis.
- Apart from infections, tumors are in some cases also responsible for the development of a renal abscess. Bacteria can settle in decaying tumor tissue of a kidney tumor and thus also cause a renal abscess.
Symptoms
Typical for a renal abscess is the so-called flank pain. This is a lateral, approximately arch-shaped pain, which is located slightly below the lower edge of the shoulder blades. This flank pain can be extremely severe and is unilateral.
The flank pain may continue to radiate into the abdomen or back. This location may also be accompanied by reddening of the skin as a sign of inflammation. A large abscess can also often be felt as a swelling under the skin.
Typical symptoms are also fever, general fatigue and chills. Urine excretion can be greatly reduced or even completely restricted, for example due to urinary retention. Complications such as urosepsis or a rupture of the abscess can lead to a very acute clinical picture with organ failure and comatose states.
Therefore, a kidney abscess should always be treated. and flank painKidney abscesses are located in close proximity to the spine and back. Depending on their size, they can even cause swelling of the back right next to the spine.
Due to the pressure on surrounding structures, kidney abscesses often lead to radiating pain in the spine. Unlike, for example, herniated discs or similar, kidney abscesses are characterized by other symptoms that are typical of an infection. These include fever, general fatigue or nausea.