Simple kidney cysts are usually harmless and do not cause any symptoms to a person affected. That is why most of them go unnoticed for a lifetime. If they are noticeable, it is usually as a chance finding in an ultrasound scan that was made for other reasons.
Pain
In very rare cases, when the cysts are very large (which really means about the size of a fist), they can sometimes cause pain by displacing the normal kidney. This pain then manifests itself as a painful pressure in the flank area. Such large kidney cysts can sometimes also cause symptoms of the gastrointestinal tract, such as abdominal pain or irregularities in the stool.
Infected kidney cysts
From time to time, kidney cysts can become infected. This can cause typical symptoms of a urinary tract infection, including pain, cloudy urine, blood in the urine and even flank pain.
Cystic kidneys
The situation is different with the cystic kidneys. These diverse and sometimes large space requirements in the kidney lead more quickly to pain, functional limitations and complications. Since this is a hereditary disease, cysts can occur in many other organs in addition to the kidney, where they can cause problems.
These organs include above all the spleen, pancreas, lungs, testicles and ovaries, thyroid gland and, more rarely, the liver. If heart valves are affected, they can no longer perform their function adequately and become permeable (insufficient), resulting in cardiac insufficiency. Many patients develop high blood pressure because the kidneys can no longer function properly.
This is because the kidney normally ensures adequate excretion of salt. If it can no longer perform this task, more salt and therefore water is retained in the body, which results in increased pressure. Hernias (inguinal hernias) also occur frequently in patients with cystic kidneys. In the worst case, the kidney may stop working completely; this results in renal insufficiency, which can ultimately be manifested by a reduced amount of urine, water retention (edema), vomiting, bleeding tendencies, headaches, fatigue and muscle twitches.