With the popularity of ultrasound, more and more liver and kidney cysts are being readily detected. Most of them are found accidentally and unexpectedly, and it is true that fewer patients with cysts are actually seen specifically for having symptoms. However, for the majority of patients, once they learn that they have liver and kidney cysts, they will be reckoning over and over again in their minds: how did the cysts come about, what adverse effects will they have on my health, and how to eliminate them? I. What are liver and kidney cysts? A cyst is a closed cavernous structure surrounded by intact fibrous tissue, resembling a cystic bag and filled with fluid. This layer of fibrous tissue is usually thin, and in its innermost layer are a number of flattened epithelial cells attached to each other in a membranous structure, like paint adhering to a wall. Between the epithelial cell layer and the fibrous tissue layer there are slender capillaries that are responsible for nourishing the epithelial cells. Epithelial cells have the role of secreting fluid, which accumulates in a closed cystic lumen called cystic fluid. The most characteristic feature of the cyst fluid is that it is richer in albumin and also contains electrolytes such as NaCl, which are similar to those found in blood plasma. In the vast majority of cases, the cyst fluid is colorless and transparent, especially in hepatic cysts. Sometimes it can be yellowish, and is relatively more common in renal cysts. In a few cases, the cyst fluid may be coffee-colored, due to bleeding from the capillaries of the cyst wall over a longer period of time, also known as old bleeding. Occasionally, the liver cyst fluid also has a light dark green color, which may originate from the infiltration of bile in the bile ducts. To date, there is no conclusive information about the exact pathogenesis of hepatic and renal cysts. Therefore, there is no reliable method of prevention. Second, what are the most important hazards of liver and kidney cysts? The first harm of cysts is the occupying effect. The cyst occupies a certain space of the organ in which it is located to form an occupying effect, i.e., it has a direct mechanical compression effect on the surrounding tissue structures. The degree of compression increases with the size of the cyst. After extrusion, the originally normal liver and kidney tissues atrophy and ischemia occur, which can even affect liver and kidney function. Some cysts are superficially located and easily compress the surrounding organs, for example, when the stomach is compressed, it easily makes people feel full and affects eating. Kidney cysts tend to protrude outward or squeeze the renal pelvis inward, which can cause significant lumbar pain and back pain when the cysts are large, and in severe cases, can cause significant restrictions on the patient’s life and living. The accumulation of fluid in the cyst cavity can sometimes lead to purulent infection, resulting in infection symptoms in patients. It is not uncommon for bleeding to occur in the cystic cavity due to increased capillary fragility of the cystic wall and compromised hepatic synthesis of coagulation factors. Stale bleeding can increase the chances of septic infection. Many people are very worried about cyst rupture, which is actually somewhat overwhelming. It is very rare that a cyst actually ruptures clinically, unless it is subjected to external violence, such as impact, fall or compression, when the risk of cyst rupture is much less than the risk of bleeding and infection due to other organ damage. Therefore, we are not worried about cyst rupture and recommend patients to receive treatment. C. What are the common types of liver and kidney cysts? The classification of cysts in pathology is considered more from the morphological and hereditary point of view of the disease, thus giving rise to such titles as simple liver or kidney cysts, polycystic kidney disease or liver disease, which are significantly different in nature. Simple liver and kidney cysts are usually small in number, one or more, and the cysts occupy only one part of the liver and kidneys, which in most cases do not lead to a significant increase in the size of the liver and kidneys, and do not cause abdominal bulging in patients; the damage to the parenchyma of the liver and kidneys is minimal, and they almost do not cause damage to liver and kidney function and hypertension, etc. Even if they are hereditary, the degree of inheritance is not high, and they have a more obvious sporadic character, which means that if one person develops the disease, his family relatives may not develop it, and there is no pattern of development. The popular use of ultrasound and other medical imaging means has significantly increased the rate of accidental detection and diagnosis of liver and kidney cysts. Under the combined influence of many factors, liver and kidney cysts are increasingly becoming common and frequent clinical diseases. In the team of liver and kidney cysts, there is a group of people with cysts called polycystic nephropathy or hepatopathy (commonly known as “polycystic liver” and “polycystic kidney”), which are caused by abnormalities such as gene deletion or translocation at a certain autosomal locus and are highly hereditary and have They are highly hereditary and have a typical familial character, often several generations in a family can have consecutive or multiple cases. It is not uncommon for a parent to develop the disease, and for the parent to develop the disease and the child to develop the disease. In the past, families with a large number of siblings could have several sisters and brothers with the disease at the same time, which could almost destroy a family. As a result, there is a phenomenon that gradually emerges: a more comprehensive ultrasound examination must be done during the premarital physical examination to find out whether you and your future spouse have “polycystic liver” or “polycystic kidney”, because the young parents-to-be are well aware of this disease. “They are afraid of passing this disease to the next generation. In the workplace, we often encounter sad scenes where both parents and children are sick, often for days without relief. Polycystic liver and polycystic kidney often exist together, and sometimes they are combined with polycystic spleen and polycystic pancreas. As the normal liver and kidney structures are replaced by cysts, the blood supply to the liver and kidney vessels is impaired by the compression of cysts, and multiple factors overlap and damage the liver and kidney functions in a vicious circle. The huge volume of liver and kidney, squeezing other organs in the abdominal cavity, make patients suffer from abdominal distension and abdominal pain, and seriously damage patients’ life and working ability. What are the examination and diagnosis means of liver and kidney cysts? If there is no imaging examination but only by the doctor’s naked eye and palpation, it is difficult to determine why and the extent and scope of the disease in the abdominal cavity that causes the patient’s abdominal bulge. Therefore, medical imaging is the most important and necessary examination and diagnostic tool for liver and kidney cysts. These include MRI, X-ray CT imaging, ultrasound imaging and so on. Ultrasound is the most commonly used method because of its simplicity, rapidity, dynamics and accuracy, which is more suitable for small cysts. Through ultrasound and other imaging examinations, it can quickly clarify whether it is a simple liver or kidney cyst or a polycystic liver or polycystic kidney; clarify the number, size, location, combined bleeding, combined septic or combined substantial tumor of the cyst; understand the degree of compression and destruction of the cyst on the liver and kidney itself and the surrounding gastrointestinal, inferior vena cava, diaphragm, etc.