Many people become aware of kidney health issues only when other conditions are diagnosed, and few understand that when kidney damage is detected early, dialysis and transplantation can be avoided. World Kidney Day highlights the importance of kidney function to good health and has the goal of reducing kidney disease and related issues globally. In 2012, World Kidney Day (8 March) focuses on awareness about kidney donation and transplantation.
For the Cochrane Renal Group, assessment of quantitative and qualitative studies investigating aspects of kidney donation, and interventions to prolong transplant life are continuing challenges.
"Improving kidney transplantation outcomes for patients and their families is the goal of transplant physicians," said Dr Angela Webster, a specialist renal and transplant physician and Deputy Co-ordinating Editor of the Cochrane Renal Group. "To reach that goal, we need access to robust, reliable and proven evidence to inform the clinical decision making process."
"We never lose sight of the importance of what we see as the ultimate gift—kidney donation—from both living and deceased donors. It is a life-affirming aspect of our work to witness the impact of successful kidney transplantation," said Dr Webster. "The value of three key aspects in kidney transplantation—organ donation, maximising transplant life, and clinical evidence—cannot be over-emphasised."
As a contribution to World Kidney Day 2012, the Cochrane Renal Group has selected a number of recent Cochrane Reviews that explore the evidence for interventions for both recipients and donors. These reviews were prepared by authors and editors in the Cochrane Renal Group.
Waiting lists for kidney transplantation continue to grow and live organ donation has become more important. The major disincentive to potential kidney donors is the pain and morbidity associated with open surgery. We identified six studies randomising 596 healthy kidney donors to either laparoscopic (keyhole) or open surgery. Keyhole surgery was associated with less pain for the donor but had similar numbers of complications that could require further treatment, surgery, or both. Donor kidneys that were obtained laparoscopically were deprived of nutrients for longer periods of time but this does not appear to have any short-term consequences on transplant function.
Up to 75% of kidney transplant recipients have high blood pressure. This review compared classes of antihypertensive agents. Sixty randomised studies, enrolling 3802 patients were included. Compared with placebo, calcium channel blockers reduced graft loss and improved kidney function. Data comparing angiotensin-converting enzyme (ACE) inhibitors with placebo were inconclusive. In direct comparison with calcium channel blockers, ACE inhibitors decreased glomerular filtration rate (GFR), proteinuria and haemoglobin, and increased hyperkalaemia; there were no comparative data for graft loss. This review suggests that calcium channel blockers may be preferred as first-line agents for hypertensive kidney transplant recipients.
Acute tubular necrosis (ATN) can prevent the immediate functioning of kidney transplant. Calcium channel blockers can improve transplant blood circulation. Thirteen randomised studies, enrolling 724 patients comparing calcium channel blockers to no calcium channel blockers were included. Treatment with calcium channel blockers in the peri-transplant period significantly decreased in the incidence of post-transplant ATN and delayed graft function. There was no difference between the groups for graft loss, mortality, or requirement for haemodialysis. This review suggests that calcium channel blockers given in the peri-operative period may reduce the incidence of ATN post-transplantation.
Cytomegalovirus (CMV) is the most common virus causing disease and death in solid organ transplant recipients (kidney, heart, liver, lung and pancreas) during the first six months after transplantation. Thirty-seven studies (2185 participants) were identified. This review shows that IgG did not reduce the risk of CMV disease or all-cause mortality compared with placebo or no treatment. The combination of immunoglobulin G with antiviral medications (aciclovir or ganciclovir) was not more effective than antiviral medications alone in reducing the risk of CMV disease or all-cause mortality. Anti-CMV vaccines and interferon did not reduce the risk of CMV disease compared with placebo or no treatment. Currently there are no indications for immunoglobulin G in the prevention of CMV disease in recipients of solid organ transplants.
One strategy used to prevent Cytomegalovirus (CMV) disease is pre-emptive treatment of people who develop evidence of early CMV infection during routine screening. Ten studies (476 participants) were identified. Compared with placebo or usual care, pre-emptive treatment significantly reduced the risk of CMV disease but not acute rejection or all-cause mortality. Pre-emptive therapy versus prophylaxis and oral versus intravenous pre-emptive treatment showed no significant difference in the risks of CMV disease or all-cause mortality.
Acute rejection is a major problem in the early period following kidney transplantation. Interleukin-2 receptor (IL-2R) antagonists can be added to a patient's immunosuppression to reduce the risk of rejection. This review identified 71 randomised studies (enrolling 10,520 patients) and found that adding IL-2R antagonists reduced the risk of graft loss or death, acute rejection, and early malignancy, but did not improve patient survival. Compared with antithymocyte globulin, IL-2R antagonist treatment caused less cytomegalovirus disease and malignancy and had fewer side effects. However, although there was no difference in clinically diagnosed acute rejection, IL-2R antagonist treatment resulted in more biopsy-proven rejection at 1 year.
This review investigated the impact of steroid avoidance and steroid withdrawal on short- and long-term transplant outcomes. Thirty studies (enrolling 5949 patients) were identified. Steroid avoidance and steroid withdrawal strategies in kidney transplantation were not associated with increased mortality or graft loss. Acute rejection was more frequent with a steroid-sparing strategy.
Urological complications after kidney transplantation contribute to patient morbidity and can compromise transplant function. We identified seven studies enrolling 1154 patients. The incidence of urological complications was significantly reduced by universal prophylactic stenting and was dependent on whether the same surgeon performed, or was in attendance, during the operations. Urinary tract infections were more common in stented patients unless they were prescribed antibiotic prophylaxis.
Patients with chronic kidney disease are at increased risk of coronary artery disease (CAD). Screening for CAD is therefore an important part of preoperative evaluation for kidney transplant candidates. This diagnostic test accuracy review compared non-invasive screening tests versus coronary angiography to detect CAD. Both dobutamine stress echocardiography (DSE; 13 studies) and myocardial perfusion scintigraphy (MPS; nine studies) had moderate sensitivity and specificity in detecting coronary artery stenosis. When limiting to studies which defined coronary artery stenosis using a reference threshold of ≥70% stenosis on coronary angiography, there was little change in these pooled estimates of accuracy. Current evidence suggests that where feasible DSE should be used as the screening investigation of choice.
Acknowledgements: This collection was created by the Cochrane Renal Group.
Image credit: World Kidney Day Global Operations Center (used with permission)
Date published: 06 March 2012
Contact: Cochrane Editorial Unit (email@example.com)