What is chronic allograft nephropathy (CAN) ?

What is chronic allograft nephropathy (CAN) ?

Chronic allograft nephropathy is the most prevalent cause of renal transplant failure in the first post-transplant decade, but its pathogenesis has remained elusive.

A common feature of chronic allograft nephropathy is that it develops in grafts that have undergone previous damage, but the mechanism responsible for the progressive fibrosis and tissue remodeling has not yet been defined.

Causes of Chronic allograft nephropathy

The quality of the transplanted tissue

There are two aspects of input quality: chronic changes from stresses and injuries in the donor, and the acute peritransplant injuries that arise in donation and transplantation. The use of older and “marginal” donors or expanded criteria for donor acceptability are increasing the importance of acute and chronic input effects. In the past, the donors were usually young male trauma victims, and now are increasingly likely to be older, with strokes, and female. The result is that nonspecific input injury is rivaling rejection as the major process causing CAN and graft failure.

Chronic pretransplant injuries

Donor age is the strongest predictor of poor long-term graft survival, and CAN lesions strongly correlate with older donor age. Kidneys from older donors show an increased frequency of later adverse features: delayed graft function and elevated baseline serum creatinine. The aging kidney develops increasing functional impairment, particularly in men, due to age and age-related diseases such as hypertension and vascular disease.

Acute peritransplant injuries

Delayed graft function (DGF) is a strong correlate of reduced graft survival, reflecting acute injury related to the donation and transplant process, although it is likely that preexisting chronic changes such as FIT also increase DGF.

Immunity

Immunologic parameters (histocompatibility differences, acute rejection episodes, presensitization) have a major effect on graft survival. Acute rejection episodes, especially if severe, recurrent, late, or not responding well to treatment, strongly predict the early development of CAN.

Kidneys from CMV-positive donors are associated with small reductions in graft survival in organ Sharing. CMV may be associated with chronic rejection of liver transplants and heart transplants.

Proteinuria

In grafts with heavy proteinuria, the filtered proteins may be toxic to the tubules. Although this cannot initiate renal injury, it may contribute to progression in some cases.

Hypertension

Hypertension in the recipient is significantly associated with CAN and late graft failure, either as a cause or an effect. Pretransplant hypertension in the recipient, the presence of the native kidneys, history of hypertension in the donor, recurrent rejection episodes, impaired graft function, and immunosuppressive drugs such as CsA and steroids correlate with posttransplant hypertension.

Hyperlipidemia

Hypercholesterolemia and hypertriglyceridemia are risk factors for the development of atherosclerosis and are common in transplant patients and presumably contribute to patient mortality from cardiac disease . The role of hyperlipidemia in the incidence of CAN is separate from the risks of generalized recipient atherosclerosis. Hypertriglyceridemia correlates with CAN, but whether lipid abnormalities cause CAN remains unproven. Increased pretransplant cholesterol levels were associated with higher graft damage scores in renal biopsies. The combination of increased triglycerides and VLDL proteins may correlate with future graft failure in kidney transplants.

Renal allograft failure is one of the most common causes of end-stage renal disease, accounting for 25 to 30 percent of patients awaiting renal transplantation.but the renal transplatation has so many complications, so the experts have invented a new treatment system.

● Hemodialysis (HD), blood perfusion (HP), plasma exchange, etc. but the continuous blood purification (CBP), blood lipid,and artificial liver support system (ALSS) is combined application by multiple technologies above, Though peritoneal dialysis without extracorporeal circulation, only in ascites exchange to achieve the purpose of purifying the blood, but from broadly speaking, also should be included within the blood purification therapy.

● on the basis of blood purification, then we take the following treatment .

Micro-Chinese Medicine Osmotherapy

Micro-Chinese Medicine Osmotherapy is external application of selected Traditional Chinese Medicine, which is applied to treat root causes by repairing renal injuries and restoring renal functions fundamentally. Its significant efficacy brings new hope for patients with Kidney Disease, which draws increasing attention worldwide.

Outspread blood vessel:

The first process aims at well controlling blood vessel, improving microcirculation, eliminating blood stasis and increasing blood and oxygen supply, thus slowing down the progression of deteriorate and providing a clean internal environment for follow-up processes.

Antiinflammatory:

Inflammatory response can be well controlled by antiinflammatory through reducing inflammatory cells invasion, which is able to terminate the process of diseased course in earlier stages.

Anticoagulation:

While anticoagulation plays the role of dissolving thrombus and enhancing renal effective perfusion, thus improving renal blood flow so as to offer a better platform for renal repair.

Degradability:

The key point of degradability is to degrade extracellular matrix with selected Traditional Chinese Medicine so as to awaken self-repairing system of kidney inherent cells, promote the regeneration and differentiation of inherent cells, rebuild the structure of the glomeruli, and recover the glomerular filtration function.

The key point of degradability is to degrade extracellular matrix with selected Traditional Chinese Medicine so as to awaken self-repairing system of kidney inherent cells, promote the regeneration and differentiation of inherent cells, rebuild the structure of the glomeruli, and recover the glomerular filtration function.

After all the process, the patients can get rid of the dialysis and get well step by step.

Through the above treatment , the renal blood flow signal of the patients will increase. The filtration rate will increase by 10 to 30, and the creatinine will decrease by 2 to 5.

Creatinine test

A creatinine test reveals important information about your kidneys. Creatinine is a chemical waste product that's produced by your muscle metabolism and to a smaller extent by eating meat. Healthy kidneys filter creatinine and other waste products from your blood. The filtered waste products leave your body in your urine. If your kidneys aren't functioning properly, an increased level of creatinine may accumulate in your blood. A serum creatinine test measures the level of creatinine in your blood and gives you an estimate of how well your kidneys filter (glomerular filtration rate). A creatinine urine test can measure creatinine in your urine.

Urine test

A urine test checks different components of urine, a waste product made by the kidneys. A regular urine test may be done to help find the cause of symptoms. The test can give information about your health and problems you may have.The kidneys take out waste material, minerals, fluids, and other substances from the blood to be passed in the urine. Urine has hundreds of different body wastes.

Blood test

Blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a needle, or via fingerprick.

Renal biopsy

Kidney biopsy is a medical procedure in which a small piece of kidney is removed from the body for examination, usually under a microscope. Microscopic examination of the tissue can provide information needed to diagnose, monitor or treat problems of the kidney.

Chronic allograft nephropathy it is characterized by a slow but

variable loss of function, often in combination with proteinuria and hypertension. The histopathology is also not specific, but transplant glomerulopathy and multilayering of the peritubular capillaries are highly characteristic. Several risk factors have been identified, such as advanced donor age, delayed graft function, repeated acute rejection episodes, vascular rejection episodes, and rejections that occur late after transplantation.

Prevetion

The most effective option to prevent chronic allograft nephropathy is to avoid graft injury from both immune and nonimmune mechanisms.

There is another option to establish the extent to which rigorous control of hypertension can prevent CAN in controlled prospective trials; this would establish that hypertension contributes to CAN.

Complication

There are 4 main complications which can occur in patients of chronic allograft nephropathy:

● Infections

The anti-rejection drugs patients take put they at greater risk for developing an infection. The most common infections after a kidney transplant are of the lungs, the surgical incision, and the urinary tract or bladder.

● High blood pressure

Some medicines can cause high blood pressure in people, other persons must take meds to control their high blood pressure. The doctor or transplant tea, will work with each person to find the one best for him.

●Rejection

Rejection is when the human body's immune system recognizes something foreign in the body and tries to destroy it. It is the most common complication of a kidney transplant and can happen any time during the life of the kidney. Rejection comes in several forms:

●Diabetes

Medications patients after a transplant can get diabetes complication. They may need to start taking insulin or increase the dose of medicines to help control their blood sugar. Symptoms of diabetes may include: increased thirst, increased frequency of urination, blurred vision, and confusion.

Healthy diet

Do not take too much salt or protein. For the things mentioned above will burden the kidney work. Also the sports drink contains extra electrolyte and salt, so the patients should pay attention. Furthermore, fried and spicy food should be stopped such as garlic, green onion, coriander etc.

No smoking

Smoking is an important risk factor that has been shown to hasten the progression of kidney disease. In addition, smoking increase high blood pressure and cardiovascular risks, two health problems that often occur along with renal disease.

Control blood sugar

High blood sugar can weaken your immune system. So control on blood sugar is very important. Get a flu shot every year, and get a tetanus booster shot every 10 years. Your doctor will likely recommend the pneumonia vaccine, as well.

Regular examination

The patients with chronic allograft nephropathy had better do regular examination in hospital to know their body situation in order to get a prompt treatment. For instance, blood test, urine test, creatinine test are common forms for the kidney patients.