Kidney Cyst (Cystic Kidney): Causes, Symptoms & Treatment

A kidney cyst is a fluid-filled cavity in or on the kidney. If several cysts form, it is called a cystic kidney. Isolated kidney cysts form sporadically (by chance), whereas cystic kidney is hereditary.

What is a kidney cyst?

A renal cyst is a sac-like or blister-like growth within or adjacent to the kidney. The outside of the renal cyst consists of smooth skin, and inside is a cavity filled with fluid. If such cysts occur only sporadically, they are harmless and do not cause any symptoms. If, on the other hand, several cysts form inside the kidney, which is called a cystic kidney, the function of the kidney can be impaired. A cystic kidney causes various symptoms and can lead to kidney failure. They usually develop hereditarily and are one of the most common inherited diseases. The single kidney cyst is also a frequently occurring kidney malformation. It rarely affects children, but the likelihood of developing a kidney cyst increases with age.

Causes

Isolated renal cysts often form without an apparent cause. This is called idiopathic development. Cystic kidney, on the other hand, is in most cases hereditary. In this case, a gene mutation is present on chromosome no. 16, and more rarely also on chromosome no. 4. A distinction is made between autosomal dominant and autosomal recessive inheritance. Both occur in cystic kidney. In autosomal dominant inheritance, the disease is transmitted to the child even if only one parent passes on the mutated gene. In autosomal recessive inheritance, cystic kidney develops in the offspring only if both parents are carriers of the defective gene. This means that even if one parent passes on the genetic defect, the disease will not develop in the child because the healthy gene of the other parent can completely take over its task. Cystic kidneys, however, can also result from long-term dialysis. Dialysis is a procedure to clean the blood, which takes over the task of diseased or too weak kidneys.

Symptoms, complaints and signs

When kidney cysts occur one at a time, no symptoms or discomfort usually develop. Often, the growths go unnoticed for many years. Larger cysts manifest as pain in the kidney area. In the further course, swelling and blood in the urine may also occur. Cystic kidneys always cause symptoms in the long term. Damage to the kidney tissue can lead to high blood pressure and urinary tract infections. In such cases, blood is frequently found in the urine or there is severe pain in the flank, which can radiate to the back and abdomen. Rarely, the pain penetrates to the hip and lower back. The symptoms lead to chronic kidney failure already in childhood. This is manifested by acute pain, digestive complaints and an increasing feeling of illness. Many patients suffer from fatigue and a reduction in mental and physical performance. If the disease is medullary sponge kidney, no symptoms appear for a long time. The disease then often only manifests itself after years, when the impaired coagulation leads to the formation of urinary stones. After that, symptoms such as colic and kidney pain appear. The signs of the disease take a gradual course and in extreme cases lead to kidney failure. If the kidney cysts or cystic kidneys are treated early with surgery and medication, the symptoms disappear almost completely.

Diagnosis and course

Single kidney cysts usually cause no symptoms and often go undetected. They are usually discovered only by chance during an ultrasound examination (sonography), during a CT (computed tomography) scan, or by an X-ray examination. In rare cases, it happens that the renal cyst becomes infected. Such an infection can cause various symptoms, such as blood in the urine, pain in the lower lateral back, and inflammation of the renal pelvis and urinary tract may occur. In cystic kidney, the kidney enlarges over time and repeated urinary tract infections with blood in the urine occur. Patients suffer from pain in the kidney area, they feel less able to perform and often have elevated blood pressure. In autosomal dominant cystic kidney disease, cyst formation often spreads to other organs, such as the lungs, spleen or liver.Sometimes heart valve defects occur with this disease. In autosomal recessive inheritance, symptoms appear in early childhood and lead to kidney failure at an early age. If cystic kidneys are suspected based on symptoms, imaging techniques (ultrasound, x-ray, CT scan) are used, as well as blood tests and renoscopy.

Complications

Simple renal cysts usually do not require treatment. They often cause no symptoms and are harmless. However, kidney cysts larger than ten centimeters can cause abdominal and back pain, renal colic, and digestive problems. Cysts can also become inflamed and lead to the formation of abscesses. Furthermore, ruptures or hemorrhages can develop in the cysts. These can cause considerable pain. In such cases, surgery may be required to relieve the pain. Cysts with a thick perfusing cell wall also need to be removed during surgery. Such kidney cysts could have portions of malignant tissue. These degenerated cysts could subsequently develop into malignant kidney tumors. If cysts occur frequently and displace healthy kidney tissue, this can be an indication of congenital and inherited cystic kidneys. This can cause serious complications. Affected patients experience massive flank, back and abdominal pain. In addition, there is often a reddish discoloration of the urine. Increasingly, affected individuals suffer from urinary tract infections such as kidney pelvic and bladder infections. These inflammations are accompanied by painful urination and occasionally fever. The cysts also promote the formation of kidney stones and high blood pressure. In the long term, congenital cystic kidney disease can damage the kidney to such an extent that it can only function to a limited extent. Affected individuals then present with renal insufficiency, which can result in kidney failure.

When should you see a doctor?

Kidney pain, blood in the urine and high blood pressure indicate a kidney cyst. Such a growth must be diagnosed and treated quickly to avoid the development of further cysts. Should other complaints arise, such as recurrent urinary tract infections or intestinal diverticula, the sufferer should talk to their family doctor immediately. People who have an unhealthy lifestyle and regularly consume alcohol or other drugs, for example, are at increased risk of developing a kidney cyst. Taking certain medications and undergoing chemotherapy or radiation treatments can also cause a kidney cyst under certain circumstances. Affected persons should have the above symptoms clarified immediately. This is particularly necessary if the cyst has already caused severe discomfort. A kidney cyst can be diagnosed by a general practitioner. Treatment is provided by various specialists such as nephrologists or gastroenterologists. Large growths must be removed in the hospital. Accompanying symptomatic treatment, patients should see a nutritionist and work out a diet together. Psychological counseling can identify and treat psychological triggers.

Treatment and therapy

A renal cyst usually does not require treatment because it does not cause any symptoms. Only if the cyst is very large is it punctured. This involves piercing the lump with a hollow needle and aspirating the fluid. The substance is then examined in a laboratory for possible pathogens and for its composition. Cystic kidney cannot be treated curatively because the cause lies in the genes. Pain-relieving medications can be given for pain. If the cysts are very large, puncture also provides relief and reduces pain. In the long run, however, the kidney will no longer be able to fulfill its function due to the many cysts, and blood cleansing must take place via dialysis. There are two different procedures, hemodialysis (HD) and peritoneal dialysis (PD). In hemodialysis, which is more commonly used, blood is purified outside the body using an artificial kidney and then returned to the body. In peritoneal dialysis, the blood is filtered inside the body, through the patient’s peritoneum.However, dialysis cannot permanently replace kidney function and, in most cases, is used only as a temporary stopgap until a suitable organ is available for kidney transplantation.

Outlook and prognosis

The prognosis of a renal cyst can vary widely. Normally, no further medical care is needed because there are no symptoms and the cyst is harmless in appearance. It often remains undetected for a long time and detaches on its own as it progresses. It is automatically removed from the body and does not require any further medical activities. In the case of hereditary development of kidney cysts, however, they should be monitored by a doctor and checked regularly. Here, the risk of complications and the development of various complaints increases. Due to genetics, the development of cysts in the area of the kidney occurs repeatedly in the course of life. If they develop unfavorably, they can lead to various complaints and health impairments. If the cyst grows in an unfavorable region, it is removed as quickly as possible by a minor surgical procedure. In some patients, mutation of the existing renal cyst occurs. This usually occurs when the renal cyst remains in the organism for several years. The prognosis is significantly worsened in such a development. If left untreated, the malignant tissue alteration then leads to the development of renal tumors. In an advanced stage of the disease, these can lead to premature death of the affected person. Therefore, they must be surgically removed at an early stage.

Prevention

Kidney cysts cannot be prevented. However, if there are already known cases of cystic kidneys in the family, it is advisable to use genetic testing to determine whether a gene mutation is present.

Follow-up

In the case of a renal cyst, the patient usually has no or only very few and limited measures of direct aftercare available. For this reason, the patient should ideally see a physician at an early stage to avoid other complications or symptoms. Therefore, the main focus in this disease is early detection and treatment. As a rule, self-healing cannot occur, so that affected persons are always dependent on medical treatment. The kidney cyst can be relatively well relieved by surgical intervention. In any case, the affected person should take it easy and rest after such an operation, and refrain from exertion or stressful and physical activities. Regular checks and examinations by a doctor are also necessary after the operation in order to detect further complaints at an early stage. In many cases, a healthy lifestyle with a balanced diet can also have a positive effect on the further course of this disease. Those affected should drink plenty of fluids. Whether the kidney cyst leads to a reduced life expectancy of the affected person, can not be predicted in general.

What you can do yourself

Patients suffering from kidney cysts should independently initiate measures to alleviate their symptoms, in addition to medical and health care. Good and healthy lifestyle habits help in the recovery process and can have a preventive effect in the further course. It is particularly important to avoid alcohol, nicotine and drugs. These harmful and toxic substances have a negative effect on kidney activity and further worsen the general state of health. It is important to drink enough fluids to remove pathogens and dead tissue cells from the body. The minimum recommended amount is normally two liters of fluid per day. The consumption of natural fruit juices or non-carbonated water is advisable. Consumption of fresh fruits and vegetables is also highly recommended for building up the body’s defenses and stabilizing the immune system. Adequate physical exercise and oxygen intake further promote the patient’s health. In terms of food intake, the consumption of raw meat should be completely avoided. Every 2-3 days, a glass of water enriched with a teaspoon of sodium bicarbonate can be drunk after dinner as a supportive measure. Natron is an important everyday companion and has an antibacterial effect on the organism.Therefore, it increases the general well-being and has a health-promoting effect.