Ullman reported the first attempted human kidney transplant in 1902.66 For the next 50 years, sporadic attempts all ended in either technical failure or in graft failure from rejection. Joseph Murray performed the first successful kidney transplant in 1954, an epochal event in the history of organ transplantation. In that first case, the immunologic barrier was circumvented by transplanting a kidney between identical twins.67 For his pivotal contribution, Murray shared the Nobel Prize in Physiology or Medicine in 1990 with E. Donnall Thomas for their discoveries concerning “organ and cell transplantation in the treatment of human disease.”
The introduction of AZA (Imuran) in 1960 marked the beginning of a new era in kidney transplantation. With the combination of steroids and AZA for maintenance immunosuppression, the 1-year graft survival rate with a living related donor kidney approached 80%; with a deceased donor kidney, the rate was 65%.68 In the ensuing years, major milestones included the introduction of more effective immunosuppressive medications with lower toxicity profiles, such as polyclonal antilymphocyte globulin in the 1970s, cyclosporine in the 1980s, tacrolimus in the 1990s, and biologics in the first decade of the twenty-first century, as previously mentioned.
Parallel to the developments in medical science were the transplant community’s concerted efforts to improve use of healthcare resources. In the United States, the Social Security amendments of 1972 provided Medicare coverage for patients with end-stage renal disease (ESRD). The National Organ Transplant Act of 1984 initiated the process of creating what later became UNOS, an umbrella organization to ensure access to organs by patients in need, to enhance organ procurement and allocation, and to improve posttransplant outcomes. This infrastructure later became the blueprint for other countries to follow. As a result, organ transplantation is the most transparent field of medicine. Data such as transplant center performance are readily available on public websites; penalties for violation of regulations and for underperformance often result in transplant programs being shut down.
Today, a kidney transplant remains the most definitive and durable renal replacement therapy for patients with ESRD. It offers better survival and improved quality of life and is considerably more cost-effective than dialysis.69,70 According to the 2010 Scientific Registry of Transplant Recipients (SRTR) annual report, a total of 84,614 adult patients were on the kidney transplant waiting list, including 33,215 added just that year.71 Yet in 2009, only 15,964 adult kidney transplants were performed in the United States (9912 with a deceased donor and 6052 with a living donor). Of note, the number of patients added to the kidney transplant waiting list has increased every year, but the number of kidney transplants performed has been declining since 2006. On the positive side, posttransplant outcomes have continued to improve: in 2009, the 1-year graft survival rate with a living donor kidney was 96.5%; with a deceased donor kidney, the rate was 92.0%.
The advantages of a living donor kidney transplant include better posttransplant outcomes, avoidance of prolonged waiting time and dialysis, and the ability to coordinate the donor and recipient procedures in a timely fashion. Living donor kidney recipients enjoy better long-term outcomes, a low incidence of delayed graft function, and reduced risks of posttransplant complications. Furthermore, the elective nature of living donor kidney transplants provides unique opportunities for recipient desensitization treatment if the donor and recipient are ABO- incompatible or if the HLA cross-match results are positive.
Some of the challenges transplant professionals face today are closing the growing gap between supply and demand and thereby reducing the current prolonged waiting times; refining immunosuppressive medications to achieve better outcomes with reduced toxicity; and caring for patients who develop rejection, especially antibody-mediated rejection.
Active infection or the presence of a malignancy, active substance abuse, and poorly controlled psychiatric illness are the few absolute contraindications to a kidney transplant. Studies have demonstrated the overwhelming benefits of kidney transplants in terms of patient survival, quality of life, and cost-effectiveness, so most patients with ESRD are referred for consideration of a kidney transplant. However, to achieve optimal transplant outcomes, the many risks (such as the surgical stress to the cardiovascular system, the development of infections or malignancies with long-term immunosuppression, and the psychosocial and financial impacts on compliance) must be carefully balanced.
Any problems detected during the evaluation of transplant candidates are communicated to their referring physician and/or to a specialist if advanced evaluation and treatment are needed, ultimately improving overall care. Essentially, the pretransplant evaluation is a multifaceted approach to patient education and disease management.
Before the pretransplant medical evaluation begins, kidney transplant candidates are encouraged to attend a group meeting focused on patient education. The meeting is coordinated by a transplant physician or surgeon. The intent is to familiarize patients with the pretransplant evaluation process and with pertinent medical concepts and terms. In an open forum format, important decisions such as type of donor (living vs. deceased) are discussed. The group meeting empowers patients to fully participate in their care and serves as an impetus for a meaningful dialogue with healthcare professionals.
Diabetes and hypertension are the leading causes of chronic renal disease. Concomitant cardiovascular disease (CVD) is a common finding in this population. An estimated 30% to 42% of deaths with a functioning kidney graft are due to CVD.72,73 Therefore, assessment of the potential kidney transplant candidate’s cardiovascular status is an important part of the pretransplant evaluation.
In fact, the American Heart Association and the American College of Cardiology Foundation recently published their expert consensus on CVD evaluation and management for solid organ transplant candidates.74 The process should focus on careful screening for the presence of significant cardiac conditions (e.g., angina, valvular disease, and arrhythmias) and for a prior history of congestive heart failure, coronary interventions, or valvular surgery. The perioperative risk assessment is based on patient symptoms and exercise tolerance. For all kidney transplant candidates, a resting 12-lead electrocardiogram (ECG) should be obtained. In addition, in this population, the use of echocardiography to analyze left ventricular function and to assess for pulmonary hypertension is useful.
Stress testing may be considered in patients with no active cardiac condition but with risk factors such as diabetes, hemodialysis for more than 1 year, left ventricular hypertrophy, age greater than 60 years, smoking, hypertension, and dyslipidemia. The utility of noninvasive stress testing (as compared with angiographic studies) for evaluating coronary artery disease is controversial; an additional prognostic marker is the troponin T (cTnT) level.
Because of the long-term use of immunosuppressive medications, transplant recipients are at increased risk for development of malignancies. Untreated and/or active malignancies are absolute contraindications to a transplant (with two exceptions: nonmelanocytic skin cancer and incidental renal cell cancer identified at the time of concurrent nephrectomy [i.e., for polycystic kidney disease] and renal transplantation). For most patients who have undergone treatment of low-grade tumors with a low risk of recurrence (e.g., completely locally excised low-grade squamous cell cancer of the skin, colon cancer in a polyp absent stalk invasion), a wait of at least 2 years after successful treatment is recommended before a kidney transplant can be considered. However, for certain types of tumors, especially at advanced stages or those with a high risk of recurrence (e.g., melanoma, lymphoma, renal cell cancer, breast cancer, colon cancer), a delay of at least 5 years is advisable. According to the Israel Penn International Transplant Tumor Registry, tumor recurrence posttransplant is not infrequent: the recurrence rate is 67% in patients with multiple myeloma, 53% in nonmelanocytic skin cancer, 29% in bladder cancer, and 23% in breast cancer.75
A thorough history of infections and immunizations should be obtained from transplant candidates, who need all recommended age-appropriate vaccinations according to the Centers for Disease Control and Prevention (CDC) guidelines. Ideally, vaccinations should be completed at least 4 to 6 weeks before the kidney transplant takes place. Immunosuppressive medications blunt the immune response and reduce the effectiveness of vaccinations; even more important, with attenuated vaccines, vaccine-derived infections could occur. If a splenectomy is anticipated (e.g., in recipients whose donor is ABO-incompatible or whose HLA cross-match results are positive), then they should be immunized against encapsulated organisms (such as Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae) well in advance of the splenectomy.
Transplant candidates should undergo routine tuberculosis (TB) screening. According to the latest CDC report, in 2011, 3929 TB cases were diagnosed in persons born in the United States and 6546 were diagnosed in foreign-born persons.76 Serologic screening combined with a chest roentgenogram for fungal infections such as coccidioidomycosis or histoplasmosis, in patients who either have a history of those infections or are from an endemic area, are recommended. Chronic infections such as osteomyelitis or endocarditis must be fully treated; a suitable waiting period after successful treatment must occur, in order to ensure that relapse does not occur.
Hepatitis can be caused by five different type of viruses, hepatitis virus A, B, C, D, and E, with the first three being the most common. Acute viral hepatitis is a contraindication to a kidney transplant; however, chronic viral hepatitis (most commonly caused by hepatitis B [HBV] or C [HCV]) does not preclude a recipient from undergoing a kidney transplant. In such candidates, obtaining a liver biopsy is essential to assess the disease severity. Recipients infected with HBV should undergo antiviral treatment (e.g., lamivudine) to prevent reactivation and progression of liver disease. Note that HBV is a noncytopathic virus; the liver damage is the result of an immune-mediated process.77 Moreover, the presence of normal liver enzymes in patients with HBV antigenemia does not predict the severity of parenchymal damage.
Transplant candidates with chronic HCV infection often have HCV-related glomerulonephritis. As with HBV infection, the clinical presentation and biochemical findings with HCV infection are often unreliable in predicting liver damage. In patients with evidence of cirrhosis, a combined liver-kidney transplant should be considered. In appropriate candidates, pretransplant antiviral treatment with interferon-α may be considered. However, after a kidney transplant, interferon treatment is not recommended, because it may precipitate graft rejection.
Thanks to the excellent outcomes of highly active antiretroviral therapy (HAART), infection with HIV is no longer considered a contraindication to a kidney transplant. Kidney transplant candidates with HIV must have an undetectable HIV viral load and a CD4 lymphocyte count greater than 200/mm3; in addition, they must not have had any opportunistic infection in the previous year.78
Latent viral infections such as CMV and EBV are of particular interest, given the risks of reactivation posttransplant and the detrimental effects on graft and patient survival. Knowing the serologic status of CMV and EBV infections helps transplant professionals gauge the risk of immunosuppressive regimens and the impact of the donor’s viral status, thereby guiding plans for posttransplant antiviral prophylaxis treatment or, as noted earlier, avoiding transplants between a seropositive donor and a seronaive recipient.
The third most common cause of graft loss in kidney transplant recipients is recurrence of glomerular diseases such as focal segmental glomerulosclerosis (FSGS), immunoglobulin A (IgA) nephropathy, hemolytic uremic syndrome, systemic lupus erythematosus, and membranoproliferative glomerulonephritis. FSGS deserves special mention for its frequent occurrence and dramatic presentation of early graft loss. An estimated 30% to 40% of FSGS patients develop recurrent disease posttransplant; of those, up to half eventually lose their graft.79 In recipients with a history of FSGS, posttransplant nephrotic proteinuria should be promptly investigated; if diagnosis is confirmed by kidney biopsy, rescue plasmapheresis should be instituted at once. Adjuvant therapy with rituximab recently has been proposed.80
Kidney transplant candidates with a history of thrombotic events, repeated miscarriages, or a family history of thrombophilia should be screened for the following coagulopathic disorders: activated protein C resistance ratio, factor V Leiden mutation, factor II 20210 gene mutation, antiphospholipid antibody, lupus anticoagulation, protein C or S deficiency, antithrombin III deficiency, and hyperhomocysteinemia. In recipients at risk for hypercoagulopathy, pediatric kidney grafts should be avoided; so should any kidney allografts with a complex vascular anatomy.81 A perioperative anticoagulation protocol is recommended in this population.
Kidney transplant candidates (pediatric patients, in particular) with chronic kidney disease as a result of congenital or genitourinary abnormalities should undergo a thorough urologic evaluation. A voiding cystourethrogram and a complete lower urinary tract evaluation to rule out outlet obstruction are essential. Indications for a native nephrectomy include chronic pyelonephritis, large polycystic kidneys with loss of intra-abdominal domain, significant vesicoureteral reflux, or uncontrollable renovascular hypertension.
The potential implant sites for a kidney graft include the recipient’s aorta, vena cava, and iliac vessels. Careful physical examination often reveals significant central and/or peripheral vascular disease. Findings such as a pulsatile intra-abdominal mass, diminished or absent peripheral pulse, claudication, rest pain, and tissue loss in lower extremities should be further evaluated by abdominal computed tomography scan or ultrasound, Doppler studies, and/or angiography. With the popularity of endovascular interventions, transplant surgeons should also be familiar with such technology and have detailed anatomic studies of patients with vascular stents.
ABO blood typing and HLA typing (HLA-A, -B, and -DR) are required before a kidney transplant. The method of screening for preformed antibodies against HLA antigens (because of prior transplants, blood transfusions, or pregnancies) is evolving. The panel-reactive antibody (PRA) assay is a screening test that examines the ability of serum from a kidney transplant candidate to lyse lymphocytes from a panel of HLA-typed donors. A numeric value, expressed as a percentage, indicates the likelihood of a positive cross-match with a donor. A higher PRA level identifies patients at high risk for a positive cross-match and therefore serves as a surrogate marker to measure the difficulty of finding a suitable donor and the risk of graft rejection.
The latest development in anti-HLA antibody screening is Luminex technology, using HLA-coated fluorescent microbeads and flow cytometry. In theory, this technology pinpoints donor-specific antibodies (DSAs) in the serum of a kidney transplant candidate with a high PRA level. Since all organ donors must undergo HLA typing, a negative cross-match for recipients with a high PRA level can be ensured by avoiding the selection of donors carrying unacceptable antigens (i.e., a virtual cross-match).82 Kidney transplant candidate data (including ABO blood types, HLA types, and DSAs) are now entered into a nationwide central database to facilitate deceased donor kidney allocation, as described earlier.
Psychiatric disorders have been recognized as important contributing factors to poor outcomes posttransplant. Patients with uncontrolled psychiatric disorders are at high risk for noncompliance with treatment, impaired cognitive function, and the development of substance abuse. The psychosocial evaluation is essential to ensure that transplant candidates understand the risks and benefits of the procedure and that they adhere to the lifetime immunosuppressive medication regimen.
Kidney allografts usually are transplanted heterotopically. The iliac fossa is recognized as the ideal position because of its proximity to the recipient’s bladder and iliac vessels.83,84
Retroperitoneal allograft placement also allows easy access for percutaneous biopsies and interventions for ureteral complications. The right iliac fossa is the preferred site because of its easy access to the recipient’s iliac vessels. However, if a pancreas transplant is anticipated in the future or if now failed kidney grafts have been placed at the right iliac fossa, then the left iliac fossa is used for implantation. The current surgical technique for kidney transplants was developed and popularized in the 1950s and 1960s and has changed little since.85
A large-bore three-lumen urinary catheter is inserted after the recipient is anesthetized, and it is occluded with a clamp beneath the surgical drapes. Recipients whose native kidneys produce urine will naturally fill up the urinary bladder; those individuals whose kidneys do not will require insufflation of saline prior to creation of the ureteral anastomosis.
Exposure of the operative field starts with a curvilinear skin incision, one to two finger widths above the midline pubic bone and the lateral edge of the rectus sheath. Superiorly, the extension of the incision depends on the recipient’s body habitus and the size of the donor kidney. The anterior rectus sheath is incised, medially to laterally, until the lateral edge of the rectus sheath is exposed. The posterior rectus sheath is missing below the arcuate line, thus providing direct access to the extraperitoneal space. The rectus muscle can be easily mobilized medially without being divided. The remainder of the fascial incision is along the lateral edge of the rectus sheath until the desired exposure is achieved (Fig. 11-6).
Incision and exposure for kidney transplant. A. Mark for the skin incision. B. Anterior rectus sheath incised obliquely. The abdominal muscle transected lateral to the rectus muscle. C. External iliac artery and vein dissected.
The retroperitoneal space of the iliac fossa is entered by mobilizing the peritoneum medially. The inferior epigastric vessels, the round ligament (in females), and the spermatic cord and its vasculature (in males) are encountered in this space; the former two structures are divided, while the latter is retracted with a vascular loop. A self-retained retractor is used to expose the surgical field. The iliac vessels should be dissected with great care. To minimize the risk of lymphocele development postoperatively, dissection of the iliac artery should be limited; the intertwining lymphatics around the iliac vessels should be ligated. In general, the donor’s renal artery and vein are anastomosed to the recipient’s external iliac vessels in an end-to-side fashion (Fig. 11-7). In recipients with a severely calcified iliac artery, the internal iliac artery can be used as an alternative, and in select cases, an endarterectomy must be performed.
Vascular anastomoses of kidney transplant. A. Arterial anastomosis: donor renal artery with Carrel patch to recipient external iliac artery, end-to-side. B. Venous anastomosis: donor renal vein with caval extension conduit to recipient external iliac vein, end-to-side.
After restoring the circulation to the donor’s kidney, urinary continuity can be established via several approaches. The approach chosen depends on such factors as the length of the donor ureter and a recipient history of bladder surgery, native nephrectomy, or pelvic radiation. The two most common procedures to restore urinary continuity are the Leadbetter-Politano and a modification of the Lich (e.g., extravesical) ureteroneocystostomy, which actually was designed to avoid ureteral reimplantation.
During the former procedure, a large cystotomy is created in the dome of the bladder, and the donor ureter is brought through a lateral and somewhat inferior 1-cm submucosal tunnel into the bladder, the end of which is spatulated and then sewn in place without tension with interrupted absorbable sutures placed through the mucosa and submucosa on the inside of the bladder.
An extravesical ureteroneocystostomy is performed by careful dissection of a 1-cm portion of the muscular layers on the anterolateral portion of the bladder until a “bubble” of mucosa is exposed. The donor ureter is spatulated in a diamond-shaped fashion, the bladder mucosa is incised, absorbable interrupted sutures are placed in four quadrants, and a mucosa-to-mucosa anastomosis is created using running absorbable sutures with a temporary ureteral stent in place of the first three-quarters of the anastomosis. The muscular layers of the bladder are then carefully approximated over the anastomosis to prevent reflux.
The decision to place a ureteral stent depends on the surgeon, who must try to balance the risk of infectious complications with the possible technical complications of a ureteral anastomosis, but in general, this is not required except during the rarely performed donor ureter to recipient ureter anastomosis or in the case of a pediatric kidney transplant. Fixation of the donor’s kidneys is not necessary, except in the case of small kidneys (usually from a pediatric donor) or en bloc kidneys.
Grafts with Multiple Renal Arteries
In 10% to 30% of donor kidneys, multiple renal arteries are encountered. Unless kidney transplant candidates have hypercoagulopathy, grafts with multiple renal arteries fare as well as those with single vessels.86 Vascular reconstruction options include implanting the donor’s arteries separately, reconstructing the multiple arteries into a common channel, or combining multiple arteries into a common Carrel patch (Fig. 11-8).
Arterial and venous reconstruction. A. Two renal arteries combined into a single Carrel patch (arrow). Right renal vein extension conduit constructed with stapled caval patch. IVC = inferior vena cava; R = right renal vein. B. Three renal arteries anastomosed to external iliac artery separately.
Debate persists about whether to implant kidneys obtained from young donors (<5 years or whose body weight is under 20 kg) as a single en bloc unit into one recipient or separately into two recipients. The underlying issues are the shortage of donor organs, the complexity of the surgical procedure, the risks of graft thrombosis, ureteral complications, and long-term outcomes.
In en bloc kidney transplants, the donor aorta and vena cava are used as the vascular inflow and outflow conduits. Therefore, reconstruction of the en bloc graft pretransplant is key to a successful transplant. The donor’s suprarenal vena cava and aorta are oversewn. The lumbar branches of the cava and aorta are ligated. Dissection around the renal hilum should be avoided. The orientation of the cava and aorta should be clearly marked, in order to avoid torsion of the anastomosis. If the color of the two kidneys looks different after reperfusion, repositioning should be attempted to rule out vascular torsion; fixation of the en bloc kidneys to the retroperitoneum is often necessary. The donor’s ureters are implanted to the recipient’s bladder, either as two separate anastomoses or as a common patch (Fig. 11-9). Only a handful of centers have performed en bloc kidney transplants, but the long-term outcomes are encouraging.87,88
En bloc kidney transplant (3-month-old donor kidneys). A. En bloc kidneys benched. Vascular integrity tested with methylene blue (blue hue look of the kidneys). B. En bloc kidneys transplanted in to a 62-year-old woman. Donor aorta anastomosed to recipient’s external iliac artery; donor cava, to recipient’s external iliac vein.
Preoperatively, a thorough history and physical examination should be performed. Any changes in transplant candidates’ recent medical history should be investigated in great detail. In those recipients with a historically negative PRA level who have recently undergone blood transfusions, a prospective tissue cross-match is necessary to avoid graft rejection. Electrolyte panels should be checked. Emergency dialysis may be necessary for transplant candidates experiencing hyperkalemia or fluid overload.
For dialysis-dependent transplant candidates, the catheter sites should be examined preoperatively to rule out infections. Vascular access for hemodialysis is essential to avoid complications related to posttransplant acute tubular necrosis (ATN). Vascular evaluation is mandatory; any changes in results should be investigated by appropriate imaging studies.
As is routine for other major surgical procedures, transplant candidates should preoperatively undergo a chest x-ray, a 12-lead ECG, blood typing, cross-match tests, and prophylaxis against surgical site infection (by administration of a nonnephrotoxic antibiotic with activity against both common skin microflora and gram-negative pathogens); candidates should receive nothing to eat or drink.
Intraoperatively, transplant recipients should be kept well-hydrated to avoid ATN and should receive heparin prior to vascular occlusion. Before reperfusion of the transplanted kidney, the desired central venous pressure should be maintained at around 10 mmHg, and the systolic blood pressure should be above 120 mmHg. In pediatric recipients of an adult graft, a superphysiologic condition may be necessary to avoid ATN or graft thrombosis. Mannitol often is administered before reperfusion as a radical scavenger and diuretic agent, and a diuretic such as furosemide is administered as well.
Postoperatively, the guiding principles for the care of kidney transplant recipients are the same as for other surgical patients. The crucial elements include hemodynamic stability and fluid and electrolyte balance. To achieve a euvolemic state, the recipient’s urine output is replaced with either an equal or a reduced volume of IV fluid on an hourly basis, depending on the medical status. In recipients undergoing brisk dieresis, aggressive replacement of electrolytes (including calcium, magnesium, and potassium) may be necessary. In recipients experiencing ATN, fluid overload, or hyperkalemia, however, fluid restriction, treatment for hyperkalemia, and even hemodialysis may be necessary.
Hypotension is an unusual event immediately posttransplant. The differential diagnoses include hypovolemia, vasodilation, and myocardial infarction with cardiac failure. Immediate action should be taken to avoid life-threatening complications. Posttransplant hypertension can be mediated by catecholamines, fluid overload, or immunosuppressive agents.
Postoperatively, urine output is used as a surrogate marker to monitor graft function. Among recipients whose native kidneys produce significant amounts of urine, normal or increased urine output can be misleading; for them, serum blood urea nitrogen and creatinine levels are more reliable indicators of kidney graft function.
Suddenly decreased or minimal urine output requires immediate attention. A change in volume status is the most common cause, but other culprits include blockage of the urinary catheter, urinary leak, vascular thrombosis, hypotension, drug-related nephrotoxicity, ATN, and rejection (all of which must be thoroughly investigated). Diagnostic studies such as Doppler ultrasound, nuclear renograms, or biopsies should be considered.
Postoperative bleeding is an uncommon event after a kidney transplant. Recipients on anticoagulation or antiplatelet treatments are at increased risk. Signs and symptoms (such as an expanding hematoma over the surgical site, increased pain over the graft, a falling hemoglobin level, hypotension, and tachycardia) should arouse suspicion of hemorrhage. Doppler ultrasound is useful to establish the underlying cause. Surgical exploration seldom is required, because the accumulated hematoma tamponades the bleed. Indications for surgical exploration include ongoing transfusion requirement, hemodynamic instability, and graft dysfunction from hematoma compression. For recipients on anticoagulation or antiplatelet treatments, the threshold for surgical exploration is lower. Small unligated vessels at the donor’s renal hilum or recipient’s retroperitoneum are likely sources of bleeding.
One of the most devastating postoperative complications in kidney recipients is graft thrombosis. It is rare, occurring in fewer than 1% of recipients. The recipient risk factors include a history of recipient hypercoagulopathy and severe peripheral vascular disease; donor-related risk factors include the use of en bloc or pediatric donor kidneys, procurement damage, technical factors such as intimal dissection or torsion of vessels, and hyperacute rejection. Graft thrombosis usually occurs within the first several days posttransplant. Acute cessation of urine output in recipients with brittle posttransplant diuresis and the sudden onset of hematuria or graft pain should arouse suspicion of graft thrombosis. Doppler ultrasound may help confirm the diagnosis. In cases of graft thrombosis, an urgent thrombectomy is indicated; however, it rarely results in graft salvage.
Urologic complications are seen in up to 5% of recipients. The cause is often related to ureteral ischemia, damage during procurement of the donor’s distal ureter, or technical errors. Symptoms of urine leak include fever, pain, swelling at the graft site, increased creatinine level, decreased urine output, and cutaneous urinary drainage. Diagnosis can be confirmed by a combination of ultrasound, nuclear renography, drainage of perinephric fluid collection, and comparison of serum and fluid creatinine levels. Depending on the location and volume of the urine leak, satisfactory results can be achieved by surgical exploration and repair or by percutaneous placement of a nephrostomy and ureteral stenting.
Early urinary obstruction can be due to edema, blood clots, torsion of the ureter, or compression from a hematoma. Late urinary obstruction is often related to ischemia. The appearance of hydronephrosis on ultrasound is a good initial indicator. Treatment includes percutaneous placement of a nephrostomy and ureteral stenting. If transluminal intervention fails, surgical intervention (such as ureteral reimplantation or a ureteropyelostomy) can be undertaken.
A kidney transplant remains the most common solid organ transplant in the world today. With the introduction of induction immunosuppressive therapy and ever-improving, less toxic immunosuppressive medications, posttransplant outcomes have become better and better. According to a recent analysis of more than 250,000 U.S. adult kidney transplant recipients, the actual half-life (50% graft survival) of a deceased donor kidney was 6.6 years in 1989, 8 years in 1995, and 8.8 years in 2005. Interestingly, during that same period—though with a much better overall outcome—the half-life of a living donor kidney has essentially remained the same: 11.4 years in 1989 and 11.9 years in 2005.89
The biggest improvements have been in the reduction of 1-year graft failure. With a deceased donor kidney, the 1-year graft failure rate dropped from 20% in 1989 to less than 7% in 2009; with a living donor kidney, the rate dropped from 8.5% in 1989 to less than 3% in 2009.89 Furthermore, steroid-free protocols90 and calcineurin-free protocols91 have been validated and implemented in the last two decades, further reducing medication-related side effects and vastly improving the quality of life for tens of thousands of recipients.
Currently, the most common cause of graft loss is recipient death (usually from cardiovascular causes) with a functioning graft. The second most common cause is chronic allograft nephropathy; characterized by a slow, unrelenting deterioration of graft function, it likely has multiple causes (both immunologic and nonimmunologic).92,93 The graft failure rate due to complications related to surgical technique has remained at about 2%.