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DictionarySeetransplantationEncyclopediaSeeTransplantationKidney Transplantation
Kidney Transplantation DefinitionKidney transplantation is a surgical procedure to remove a healthy, functioning kidney from a living or brain-dead donor and implant it into a patient with non-functioning kidneys.National Transplant Waiting List By Organ Type (June 2000) |
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Organ Needed | Number Waiting |
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Kidney | 48,349 |
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Liver | 15,987 |
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Heart | 4,139 |
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Lung | 3,695 |
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Kidney-Pancreas | 2,437 |
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Pancreas | 942 |
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Heart-Lung | 212 |
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Intestine | 137 |
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PurposeKidney transplantation is performed on patients with chronic kidney failure, or end-stage renal disease (ESRD). ESRD occurs when a disease or disorder damages the kidneys so that they are no longer capable of adequately removing fluids and wastes from the body or of maintaining the proper level of certain kidney-regulated chemicals in the bloodstream. Without long-term dialysis or a kidney transplant, ESRD is fatal.PrecautionsPatients with a history of heart disease, lung disease, cancer, or hepatitis may not be suitable candidates for receiving a kidney transplant.DescriptionKidney transplantation involves surgically attaching a functioning kidney, or graft, from a brain-dead organ donor (a cadaver transplant) or from a living donor, to a patient with ESRD. Living donors may be related or unrelated to the patient, but a related donor has a better chance of having a kidney that is a stronger biological "match" for the patient.The surgical procedure to remove a kidney from a living donor is called a nephrectomy. The kidney donor is administered general anesthesia and an incision is made on the side or front of the abdomen. The blood vessels connecting the kidney to the donor are cut and clamped, and the ureter is also cut between the bladder and kidney and clamped. The kidney and an attached section of ureter is removed from the donor. The vessels and ureter in the donor are then tied off and the incision is sutured together again. A similar procedure is used to harvest cadaver kidneys, although both kidneys are typically removed at once, and blood and cell samples for tissue typing are also taken.Laparoscopic nephrectomy is a form of minimally-invasive surgery using instruments on long, narrow rods to view, cut, and remove the donor kidney. The surgeon views the kidney and surrounding tissue with a flexible videoscope. The videoscope and surgical instruments are maneuvered through four small incisions in the abdomen. Once the kidney is freed, it is secured in a bag and pulled through a fifth incision, approximately 3 in (7.6 cm) wide, in the front of the abdominal wall below the navel. Although this surgical technique takes slightly longer than a traditional nephrectomy, preliminary studies have shown that it promotes a faster recovery time, shorter hospital stays, and less post-operative pain for kidney donors.Once removed, kidneys from live donors and cadavers are placed on ice and flushed with a cold preservative solution. The kidney can be preserved in this solution for 24-48 hours until the transplant takes place. The sooner the transplant takes place after harvesting the kidney, the better the chances are for proper functioning.During the transplant operation, the kidney recipient patient is typically under general anesthesia and administered antibiotics to prevent possible infection. A catheter is placed in the bladder before surgery begins. An incision is made in the flank of the patient and the surgeon implants the kidney above the pelvic bone and below the existing, non-functioning kidney by suturing the kidney artery and vein to the patient's iliac artery and vein. The ureter of the new kidney is attached directly to the bladder of the kidney recipient. Once the new kidney is attached, the patient's existing, diseased kidneys may or may not be removed, depending on the circumstances surrounding the kidney failure.Since 1973, Medicare has picked up 80% of ESRD treatment costs, including the costs of transplantation for both the kidney donor and recipient. Medicare also covers 80% of immunosuppressive medication costs for up to three years, although federal legislation was under consideration in early 1998 that may remove the time limit on these benefits. To qualify for Medicare ESRD benefits, a patient must be insured or eligible for benefits under Social Security, or be a spouse or child of an eligible American. Private insurance and state Medicaid programs often cover the remaining 20% of treatment costs.Kidney transplantation involves the surgical attachment of a functioning kidney, or graft, from a donor to a patient with end-stage renal disease (ESRD). During the procedure, the surgeon makes an incision in the patient's flank and implants the new kidney above the pelvic bone and below the non-functioning kidney by suturing the kidney artery and vein to the patient's iliac artery and vein. The ureter of the new kidney is then attached directly to the bladder of the patient. (Illustration by Electronic Illustrators Group.)PreparationPatients with chronic renal disease who need a transplant and do not have a living donor register with United Network for Organ Sharing (UNOS) will be placed on a waiting list for a cadaver kidney transplant. UNOS is a non-profit organization that is under contract with the federal government to administer the Organ Procurement and Transplant Network (OPTN) and the national Scientific Registry of Transplant Recipients (SR). Kidney availability is based on the patient's health status. The most important factor is that the kidney be compatible to the patient's body. A human kidney has a set of six antigens, substances that stimulate the production of antibodies. (Antibodies then attach to cells they recognize as foreign and attack them.) Donors are tissue-matched for 0 to 6 of the antigens, and compatibility is determined by the number and strength of those matched pairs. Patients with a living donor who is a close relative have the best chance of a close match.Potential kidney donors undergo a complete medical history and physical examination to evaluate their suitability for donation. Extensive blood tests are performed on both donor and recipient. The blood samples are used to tissue type for antigen matches, and confirm that blood types are compatible. A panel of reactive antibody (PRA) is performed by mixing white blood cells from the donor and serum from the recipient to ensure that the recipient antibodies will not have a negative reaction to the donor antigens. A urine test is performed on the donor to evaluate his kidney function. In some cases, a special dye that shows up on x rays is injected into an artery, and x rays are taken to show the blood supply of the donor kidney (a procedure called an arteriogram).Once compatibility is confirmed and the physical preparations for kidney transplantation are complete, both donor and recipient may undergo a psychological or psychiatric evaluation to ensure that they are emotionally prepared for the transplant procedure and aftercare regimen.AftercareKidney donors and recipients will experience some discomfort in the area of the incision. Pain relievers are administered following the transplant operation. Patients may also experience numbness, caused by severed nerves, near or on the incision.A regimen of immunosuppressive, or anti-rejection, medication is prescribed to prevent the body's immune system from rejecting the new kidney. Common immunosuppressants include cyclosporine, prednisone, and azathioprine. The kidney recipient will be required to take immunosuppressants for the life span of the new kidney. Intravenous antibodies may also be administered after transplant surgery. Daclizumab, a monoclonal antibody, is a promising new therapy that can be used in conjunction with standard immunosuppressive medications to reduce the incidence of organ rejection.Transplant recipients may need to adjust their dietary habits. Certain immunosuppressive medications cause increased appetite or sodium and protein retention, and the patient may have to adjust his or her intake of calories, salt, and protein to compensate.RisksAs with any surgical procedure, the kidney transplantation procedure carries some risk for both a living donor and a graft recipient. Possible complications include infection and bleeding (hemorrhage). The most common complication for kidney recipients is a urine leak. In approximately 5% of kidney transplants, the ureter suffers some damage, which results in the leak. This problem is usually correctable with follow-up surgery.The biggest risk to the recovering transplant recipient is not from the operation or the kidney itself, but from the immunosuppressive medication he or she must take. Because these drugs suppress the immune system, the patient is susceptible to infections such as cytomegalovirus (CMV) and varicella (chickenpox). The immunosuppressants can also cause a host of possible side effects, from high blood pressure to osteoporosis. Prescription and dosage adjustments can lessen side effects for some patients.Normal resultsThe new kidney may start functioning immediately, or may take several weeks to begin producing urine. Living donor kidneys are more likely to begin functioning earlier than cadaver kidneys, which frequently suffer some reversible damage during the kidney transplant and storage procedure. Patients may have to undergo dialysis for several weeks while their new kidney establishes an acceptable level of functioning.The success of a kidney transplant graft depends on the strength of the match between donor and recipient and the source of the kidney. Cadaver kidneys have a four-year survival rate of 66%, compared to an 80.9% survival rate for living donor kidneys. However, there have been cases of cadaver and living, related donor kidneys functioning well for over 25 years.Studies have shown that after they recover from surgery, kidney donors typically have no long-term complications from the loss of one kidney, and their remaining kidney will increase its functioning to compensate for the loss of the other.Abnormal resultsA transplanted kidney may be rejected by the patient. Rejection occurs when the patient's immune system recognizes the new kidney as a foreign body and attacks the kidney. It may occur soon after transplantation, or several months or years after the procedure has taken place. Rejection episodes are not uncommon in the first weeks after transplantation surgery, and are treated with high-dose injections of immunosuppressant drugs. If a rejection episode cannot be reversed and kidney failure continues, the patient will typically go back on dialysis. Another transplant procedure can be attempted at a later date if another kidney becomes available.ResourcesOrganizationsAmerican Association of Kidney Patients. 100 S. Ashley Drive, #280, Tampa, FL 33602. (800) 749-2257. http://www.aakp.org.American Kidney Fund (AKF). Suite 1010, 6110 Executive Boulevard, Rockville, MD 20852. (800) 638-8299. 〈http://www.arbon.com/kidney〉.National Kidney Foundation. 30 East 33rd St., New York, NY 10016. (800) 622-9010. http://www.kidney.org.United Network for Organ Sharing (UNOS). 1100 Boulders Parkway, Suite 500, P.O. Box 13770, Richmond, VA 23225-8770. (804) 330-8500. http://www.unos.org.United States Renal Data System (USRDS). The University of Michigan, 315 W. Huron, Suite 240, Ann Arbor, MI 48103. (734) 998-6611. 〈http://www.med.umich.edu/usrds〉.OtherTransweb. http://www.transweb.org.Key termsArteriogram — A diagnostic test that involves viewing the arteries and/or attached organs by injecting a contrast medium, or dye, into the artery and taking an x ray.Dialysis — A blood filtration therapy that replaces the function of the kidneys, filtering fluids and waste products out of the bloodstream. There are two types of dialysis treatment—hemodialysis, which uses an artificial kidney, or dialyzer, as a blood filter; and peritoneal dialysis, which uses the patient's abdominal cavity (peritoneum) as a blood filter.Iliac artery — Large blood vessel in the pelvis that leads into the leg.Immunosuppressive medication — Drugs given to a transplant recipient to prevent his or her immune system from attacking the transplanted organ.Rejection — The process in which the immune system attacks tissue it sees as foreign to the body.Videoscope — A surgical camera.transplantation (trans?plan'ta'shon) 1. The grafting of living tissue from its normal position to another site or the transferring of an organ or tissue from one person to another. Organs and tissues successfully transplanted include the heart, lung, kidney, liver, pancreas, cornea, large blood vessels, tendon, cartilage, skin, bone, and bone marrow. Brain tissue has been implanted experimentally to treat patients with Parkinson's disease. The matching of histocompatibility antigens that differentiate one person's cells from another's helps prevent rejection of donated tissues. Cyclosporine, tacrolimus, corticosteroids, monoclonal antibodies, and other immunosuppressive agents have been approx. 80% effective in preventing rejection of transplanted organs for 2 or more years. See: autotransplantation; graft; heart transplantation; organ donation; renal transplantation; replantationCAUTION!Patients who have received organ transplants and who are maintained on immunosuppressant drugs should generally avoid vaccination with live, attenuated organisms unless these vaccinations are specifically approved by their health care providers. Inactive vaccines are usually preferable for these patients.2. In dentistry, the transfer of a tooth from one alveolus to another.allogeneic transplantationTransplantation of material from a donor to another person.autologous chondrocyte transplantationAutologous chondrocyte implantation.autologous transplantationTransplantation of tissue or cells from one location in the body to another site.autologous bone marrow transplantation Abbreviation: ABMT The harvesting and preservation of a patient's own blood-forming cells, followed by their eventual reintroduction into a patient. The procedure may be used to treat a variety of cancers and blood disorders. Current practice is to mobilize stem cells into the blood stream with growth factors and then to collect and filter the blood by leukapheresis. In leukapheresis stem cells are identified by a cell surface antigen called CD34. After desirable blood-forming cells with this antigen are removed from the patient's blood, high-dose chemotherapy, monoclonal antibody therapy, or radiation may be used to purge the marrow of diseased cells. Healthy CD34+ cells capable of rebuilding the bone marrow are then returned to the patient and stimulated to reproduce. Synonym: autologous hematopoietic stem cell transplantationautologous hematopoietic stem cell transplantationAutologous bone marrow transplantation.autoplastic transplantationTransplantation of tissue from one part to another part of the same body. bone marrow transplantation Abbreviation: BMT Transplantation of blood-forming stem cells from the bone marrow from one person to another (allogeneic transplantation), or from a person to him or herself (autologous transplantation). It is used in treating aplastic anemia, thalassemia and sickle cell anemia, immunodeficiency disorders, acute leukemia, chronic myelogenous leukemia, non-Hodgkin's lymphoma, Hodgkin's disease, and testicular cancer, and after radiation therapy, as indicated. chain transplantationThe pairing of living organ donors who want to give an organ to someone with whom they are antigenically mismatched with other pairs of donors and recipients who share appropriate antigens, antibodies, and blood types.double transplantationTandem transplantation.fat transplantationIn cosmetic surgery, the movement of adipose tissue from one body site to another to augment structure, change body contours, or reduce skin wrinkling.hair transplantationA surgical procedure for placing plugs of skin containing hair follicles from one body site to another. This time-consuming technique is used to treat baldness. heart transplantationSurgical transplantation of the heart from a patient who died of trauma or a disease that left the heart intact and capable of functioning in the recipient. The only absolute contraindications are uncontrollable cancer or infection, irreversible pulmonary vascular disease, or a separate life-threatening disease; in general, however, patients over 65 years, those with severe renal or liver disease, and those with a history of noncompliance with medical regimens do not receive heart transplants. The major barrier to heart transplantation is the lack of donors; the number of potential recipients is approx. 10 times the number of donors each year. After receiving a heart transplant, continuous immunosuppression with cyclosporine, corticosteroids, or related drugs is required to prevent rejection of the donated organ. Acute episodes of rejection are treated with monoclonal antibodies (OKT3) or antilymphocyte immune globulin. Clinical signs of rejection (fatigue, dyspnea, hypotension, and extra heart sounds) are nonspecific; therefore biopsies are performed frequently during the first 2 years after surgery. Average patient survival is greater than 75% 1 year after the surgery, and greater than 50% after 10 years. See: rejection (2)hematopoietic cell transplantation Abbreviation: HCT Removal of blood-forming cells from one person and their infusion into another. It is used primarily but not exclusively to treat leukemias and lymphomas. heteroplastic transplantationTransplantation of a part from one individual to another individual of an unrelated species.heterotopic transplantationTransplantation in which the transplant is placed in a different location in the host than it had been in the donor.homoplastic transplantationhomotopic transplantationTransplantation in which the transplant occupies the same location in the host as it had in the donor.kidney transplantationRenal transplantation.liver transplantationSurgical implantation of a donor liver into a patient with end-stage liver disease. The disease may be caused by alcoholic cirrhosis, chronic cholestatic diseases, chronic or fulminant hepatitis, or toxic liver destruction. Immunosuppressive drugs (such as cyclosporine) must be taken after the procedure to prevent rejection of the grafted organ. With optimal care, about 75% of grafted livers remain functional after 1 yr. Patients with HIV or uncontrolled systemic infections, metastatic cancer, active alcoholism, or other severe cardiac, pulmonary, or neurological illnesses are not candidates for the procedure. In the U.S. about 4000 liver transplants are performed annually. lung transplantationGrafting of a donor lung into a recipient with end-stage lung disease, usually caused by pulmonary fibrosis, chronic obstructive lung disease, or pulmonary hypertension. Lung transplantation may be performed as a single-organ operation or as part of a combined heart-lung transplantation, e.g., in congenital heart disease. Immunosuppressive therapy with cyclosporine or tacrolimus, azathioprine, and corticosteroids is necessary to minimize the risk of rejection, which is caused by T lymphocyte activity against the donor tissue. Rejection is diagnosed through the use of bronchial biopsies and pulmonary function tests. Acute rejection, characterized by dyspnea, fever, hypoxemia, rales, and tachypnea, must be differentiated from infection. Chronic rejection, a problem in 25% to 50% of cases, presents as bronchiolitis obliterans and occurs 6 to 14 months after the transplant. Flow rates progressively decrease, with few additional symptoms; bronchodilator therapy is not effective, and giving higher doses of immunosuppressives has mixed success. Sixty percent of lung transplant recipients live 2 years. renal transplantationGrafting of a kidney from a living donor or from a cadaver to someone with renal failure. It is used as the definitive form of renal replacement for patients with kidney failure. Tissue typing for human leukocyte antigens (HLAs) as well as ABO blood groups is used to decrease the likelihood of acute or chronic rejection. Family members are often the best-matched donors. In patients with diabetes mellitus, combined renal and pancreatic transplants are sometimes performed with a very high likelihood of success. The high success rate of kidney transplants (85% to 95% at 2 years) is primarily due to immunosuppressive drugs such as corticosteroids, cyclosporine, mycophenolate, and tacrolimus. Because cyclosporine is nephrotoxic, careful monitoring of serum drug levels after transplantation is required. Synonym: kidney transplantationmajor histocompatibility complex; suppressive immunotherapy; small intestine transplantationA semi-experimental procedure in which the small intestine is replaced with a donor organ.split-liver transplantation Abbreviation: SLT Surgical division of a donor liver into two parts, each of which is implanted into a different recipient.syngeneic transplantationA specific type of allogeneic transplantation of material between identical twins.tandem transplantationThe use of sequential bone marrow transplants to treat cancer. An initial autologous transplant is followed by a second, e.g., if remission is not achieved after the first transplant. Synonym: double transplantationtransplantation of the pancreasThe implantation of a part of the pancreas (such as cells of the islets of Langerhans) or the entire gland from a donor into a patient whose own pancreas is no longer functioning. In the diabetic patient, pancreas transplantation provides an endogenous source of insulin and may be combined with kidney transplantation. The risks of the surgery and the immunosuppression associated with transplantation must be weighed against the kidney, nerve, and retinal damage associated with uncontrolled diabetes mellitus. Some potential complications of the procedure include infections, blood clotting in the vessels that supply the graft, hypoglycemia, bladder injury, and organ rejection. To prevent rejection, immunosuppressive drugs, such as tacrolimus, mycophenolate mofetil, cyclosporine, and corticosteroids, may be used. Episodes of rejection are treated with the monoclonal antibody OKT3. The 1-year survival rate of combined pancreas-kidney transplants is about 80%, when performed at institutions where the procedure is done frequently. See: diabetes mellitus; rejectionSee KLA-Tencor Corporation See KT |