End-stage renal disease, dialysis or kidney transplantation?

In daily life, most people have a certain understanding of chronic kidney disease and even end-stage kidney disease (ESRD, commonly known as uremia). This is not only because of the frequent episodes of "uremia" and "dialysis" in various TV dramas, but also closely related to China's basic national conditions-the incidence of chronic kidney disease is as high as 10%. As we all know, because the renal function of uremia patients has been completely destroyed, patients are almost inevitably faced with the dilemma of choosing dialysis treatment or kidney transplantation. In fact, these two methods of treating uremia have their own characteristics and have always been in a complementary position in kidney medicine.

Difficult "Road of Dialysis Treatment"

Dialysis therapy, as a long-term treatment for ESRD, enjoys a high reputation in China. This treatment method is to use the semi-permeable membrane of the "artificial kidney" equipment or the patient's own peritoneum to remove the toxic metabolites from the patient's blood and then return them to the circulation, thus alleviating the symptoms of renal failure caused by the accumulation of toxic metabolites and replacing the patient's kidney to some extent. Up to now, hemodialysis has played an important role in the long-term treatment of ESRD patients, and peritoneal dialysis, which has only recently been recognized by people, has also been carried out in major hospitals.

Although HD was criticized by most patients and doctors when it was first introduced as requiring patients to go to the hospital for dialysis 2-4 times a week, with the continuous development of community dialysis treatment, most patients can already regard HD as a way of life (just like many other community treatments for chronic diseases). In addition, HD treatment also has the advantages of low cost (most of the content of HD in China belongs to the scope of medical insurance reimbursement) and can effectively alleviate the symptoms related to ESRD, and it has also been welcomed by a considerable number of patients. Peritoneal dialysis can replace kidney with peritoneum, which makes it possible for patients to do it by themselves under the guidance of doctors, and solves the shortcoming that HD needs frequent medical treatment to some extent.

However, with the extensive development of dialysis treatment in the world, its shortcomings are gradually exposed. The limitation of HD treatment can be summarized in one sentence: "Almost no one can insist on dialysis treatment for more than 10 years". On the one hand, it is because of the compliance problem mentioned above (it is difficult for patients to adhere to regular treatment for a long time because of the complicated procedures), and on the other hand, because dialysis is an alternative measure for kidneys, it is difficult to really complete all the functions of normal kidneys, and those ESRD symptoms that cannot be solved by dialysis will "appear" in the long-term treatment.

Many people know that the kidney has the function of removing toxic products from the body, but in fact this is not the whole work of the kidney. In addition to eliminating toxic metabolites, the kidney also regulates human erythropoiesis by secreting erythropoietin (EPO), which also plays an important role in the balance between mineral salts (calcium, magnesium and phosphate) and electrolytes (sodium and potassium ions). However, HD can't replace the kidney to complete these two functions, which leads to the fact that most dialysis patients are not only prone to mineral salt metabolism and electrolyte disorder, but also seriously reduce their quality of life due to anemia.

Although the anemia (renal anemia) of ESRD patients has been greatly improved by EPO treatment, it is still difficult to perfectly solve the mineral salt metabolism and electrolyte disorder they suffer under the current medical level. For example, many patients with ESRD have much higher phosphate levels than the general population ("hyperphosphatemia"). At the same time, because the activation of vitamin D is impaired (vitamin D needs kidney activation to play a regulatory role), the function of parathyroid gland, an endocrine gland that regulates calcium, will also be greatly affected. Patients often need to take a variety of drugs to regulate mineral metabolism in the body, and the expensive prices of these drugs invisibly increase the cost of dialysis. Compared with the relatively chronic mineral salt metabolism disorder, electrolyte imbalance leads to higher blood potassium ion content ("hyperkalemia"), which can lead to fatal consequences within a few hours, which further increases the difficulty for doctors to manage patients with ESRD.

Kidney transplantation, the gap between ideal and reality

Because dialysis treatment is difficult to completely replace the renal function of patients with ESRD, kidney transplantation, a treatment method of directly implanting normal kidneys into patients, was once considered as a "great savior" to save patients with ESRD. Especially in 1980s, after transplantation medicine made a breakthrough-cyclosporine, an immunosuppressant that can effectively and selectively inhibit immune rejection, kidney transplantation treatment in major hospitals has mushroomed widely.

Compared with dialysis treatment, renal transplantation has obvious advantages: it can make patients have normal renal function for a long time and return to normal life; Completely replace all the work of the sick kidney to avoid complications related to dialysis; Although the short-term cost is high, it is more economical than dialysis from the perspective of long-term treatment. Therefore, with the further research on the complications of dialysis treatment and the continuous progress of kidney transplantation itself, kidney transplantation has become an important treatment for ESRD, and tens of thousands of patients worldwide receive kidney transplantation every year.

However, as the saying goes, "the ideal is full and the reality is very skinny." After the initial construction of kidney transplantation, doctors also found the gap between kidney transplantation and ideal. Because the kidney transplanted into the patient's body is a foreign organ, it will be recognized as "invasion" by the immune system and rejected, so the patient must start immunosuppression treatment before the start of kidney transplantation and continue lifelong immunosuppression. Although the medical community is constantly studying drugs that act more selectively on immune rejection, the current immunosuppressive therapy will still have a great impact on the normal immunity of patients (especially those who receive higher intensity immunosuppression because of the high risk of organ rejection). The effect of this artificial immunosuppression on patients is that many renal transplant patients will die of infection during immunosuppression or develop malignant tumors several years after transplantation.

In addition, because the organs of kidney transplantation need to be obtained from the human body (that is, the "donors" mentioned in organ transplantation), there are still very few people who have died in the world at present, which directly leads to two problems: first, the shortage of donors has greatly affected the development and research of kidney transplantation treatment, and second, the widespread demand for kidney transplantation has directly led to the phenomenon of illegal organ trading and "transplant tourism"

In view of the advantages and disadvantages of dialysis and kidney transplantation, it is very important for most patients with ESRD to choose a treatment plan. Generally speaking, dialysis treatment is suitable for patients and elderly patients who need to improve their symptoms in the short term, and can also be used as a transitional treatment while waiting for kidney transplantation; Kidney transplantation is more suitable for young patients with suitable donors and kidney transplantation conditions, and patients who are difficult to continue dialysis treatment because of dialysis-related complications.