Evaluation of living renal donors. The current practice of US transplant centers

To examine practice patterns regarding how living donors are evaluated and selected in the U.S., a survey was sent to all 231 United Network of Organ Sharing (UNOS)-approved transplant centers. Respondents from 75% of centers completed the questionnaire, all of whom utilize living donors for renal transplantation. Although the use of living-unrelated donors is also widely accepted (in 92% of centers), only 31% of responding centers performed such transplants in 1992, indicating a discrepancy between acceptance and actual practice. Morbidity (0.23%) and mortality (0.03%) of kidney donation continue to be low. The long-term risk of renal insufficiency in kidney donors appears to be similar to, or lower than, that in the general population. There is substantial variability in how potential donors are evaluated and what they are told regarding the risk involved in renal donation. There is also variability in exclusion criteria such as the acceptance of older donors (> 55 years old); those with borderline-to-mild hypertension, and those with borderline low glomerular filtration rate. Larger centers tended to be less rigid in their exclusion criteria compared with smaller centers. While our results indicate widespread acceptance and use of living donors, they also highlight the need for future studies to examine the efficacy of tests used in the evaluation process and to determine the long-term risks of renal donation.

Human mesangial cell production of monocyte chemoattractant protein-1: modulation by lovastatin

Macrophages play a critical role in the progression of clinical and experimental glomerular injury. Serum-stimulated human fetal mesangial cells in culture produce a chemotactic factor that is monocyte-selective. This chemotactic factor is most likely monocyte chemoattractant protein-1 (MCP-1) as a monoclonal antibody directed against MCP-1, but not an irrelevant antibody, suppressed the mesangial cell-derived chemotactic activity. Inhibition of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase by lovastatin resulted in a reduction of the mesangial cell-derived chemotactic activity as well as MCP-1 mRNA expression. The inhibitory effects of lovastatin in the presence of exogenous cholesterol were reversed by mevalonate, suggesting a role for isoprenoid intermediates of the mevalonate pathway and/or isoprenylated proteins in mesangial cell MCP-1 regulation. These findings suggest an additional mechanism by which HMG-CoA reductase inhibition in vivo may reduce glomerular injury.

The evaluation and selection of living kidney donors

As the number of living kidney donations in the United States increases, it is important to continue to assess the manner in which potential living donors are evaluated and selected. Ethical issues can be framed using principles that are understandable to patients and physicians. Existing evidence suggests that, for most suitable donors, the short- and long-term risks of kidney donation are small enough to be outweighed by the potential benefits to the donor and recipient. A thorough but efficient evaluation of potential living donors, as outlined in this review, can effectively minimize the risks. However, mechanisms to provide long-term follow-up of all living donors are still needed. Appropriate surveillance mechanisms not only will minimize any long-term risks to individuals who have already donated a kidney but will also provide the data needed to accurately assess the risk, however small, for future donors. With or without these data, living donations will likely continue to play an increasingly important role in renal transplantation.

Lipid-lowering therapy in patients with renal disease

A growing number of clinical trials have examined the effects of different lipid lowering strategies in patients with renal disease. We carried out a meta-analysis to compare and contrast the relative efficacy of various antilipemic therapies in different renal disease settings. Studies that investigated one or more therapies designed to lower serum lipids were combined using weighted multiple linear regression. The analysis adjusted treatment effects for differences in baseline lipid levels and possible placebo effects. The results showed that antilipemic therapies generally had similar effects on lipids in different renal disease settings. In nephrotic syndrome the greatest and most consistent reductions in low density lipoprotein cholesterol (LDL) were seen with 3-hydroxy-3-methylglutaryl co-enzyme A (HMG-CoA) reductase inhibitors (regression coefficient with 95% confidence interval in mg/dl = -63, -79 to -46). Similar results were seen for LDL in renal transplant (-51, -57 to -45), renal insufficiency (-62, -82 to -42), hemodialysis (-65, -80 to -50) and continuous ambulatory peritoneal dialysis (CAPD) patients (-84, -104 to -64). Fibric acid analogues had less effect on LDL, but caused greater reductions in triglycerides: -132, -178 to -87, in nephrotic syndrome; -69, -93 to -45 in transplant: -107, -169 to -45 in renal insufficiency; -72, -120 to -24 in hemodialysis; and -96, -162 to -30 in CAPD. In general, the effects of diet and other therapies were less consistent. Despite possible limitations of this meta-analysis, the results provide a useful framework for choosing antilipemic therapy, and point to areas for future long-term studies examining the safety and efficacy of lipid lowering strategies in patients with renal disease.

Early glomerular changes in rats with dietary-induced hypercholesterolemia

Increasing evidence suggests that lipids may be important modulators of progressive glomerular injury. We previously reported the long-term glomerular changes in rats with dietary-induced hypercholesterolemia. In this work, we evaluated the early glomerular changes induced by hypercholesterolemia that precede the development of glomerulosclerosis. In cholesterol-fed rats, an early macrophage influx was observed. This was associated with an increase in glomerular size, mesangial matrix expansion, lipid deposits, and foam cell formation. Immunohistochemical techniques showed that type IV collagen, fibronectin, and laminin were increased in cholesterol-fed rats. The mRNA expression for the alpha 1 chain of type IV collagen and an inhibitor of type IV collagenase were increased, suggesting that both increased synthesis and reduced degradation may be involved in cholesterol-induced mesangial matrix accumulation. The glomerular mRNA expression of transforming growth factor-beta 1 was also upregulated, suggesting that transforming growth factor-beta 1 could be an important mediator for mesangial matrix accumulation in hypercholesterolemic states. The early cholesterol-induced changes in the glomerulus are reminiscent in many respects to the process leading to glomerulosclerosis in the vessel wall.

Long-term effects of antihypertensive agents on proteinuria and renal function

BACKGROUND

Although many studies have examined the effects of antihypertensive agents on proteinuria and glomerular filtration rate in patients with kidney disease, many questions remain unresolved. These questions include whether the effects of agents differ, whether their effects are similar in diabetic and nondiabetic patients with renal disease, and whether the effects of any agents are independent of blood pressure reductions.

METHODS

We conducted a meta-analysis of studies obtained with MEDLINE and bibliographies from comprehensive reviews but included only investigations with follow-up times of at least 6 months. We combined data (1) in an analysis of randomized controlled trials, (2) in a separate univariate analysis of controlled and uncontrolled trials, and (3) using weighted multiple linear regression.

RESULTS

In 14 randomized controlled trials, angiotensin-converting enzyme inhibitors caused a greater decrease in proteinuria (pooled mean [95% confidence intervals], -0.51[-0.68 to -0.35], ln [treatment/control]), improvement in glomerular filtration rate (0.13 mL/min per month [0.10 to 0.16 mL/min per month]), and decline in mean arterial pressure (-4.0 mm Hg [-4.9 to -3.0 mm Hg]) compared with controls. In a multivariate analysis of controlled and uncontrolled trials, each 10-mm Hg reduction in blood pressure decreased proteinuria (regression coefficient [95% confidence interval] -0.14 [-0.22 to -0.06] ln [after/before]), but angiotensin-converting enzyme inhibitors (-0.45 [-0.58 to -0.32]) and nondihydropyridine calcium antagonists (-0.38 [-0.70 to -0.06]) were associated with additional declines in proteinuria that were independent of blood pressure changes and diabetes. Each 10-mm Hg reduction in blood pressure caused a relative improvement in glomerular filtration rate (0.18 mL/min per month [0.04 to 0.31 mL/min per month]), but among diabetic patients there was a tendency for dihydropyridine calcium antagonists to cause a relative reduction in glomerular filtration rate (-0.68 mL/min per month [-1.31 to -0.04 mL/min per month]).

CONCLUSIONS

Long-term beneficial effects of antihypertensive agents on proteinuria and glomerular filtration rate are proportional to blood pressure reductions and are similar in diabetic and nondiabetic patients with renal disease. In addition, angiotensin-converting enzyme inhibitors, and possibly nondihydropyridine calcium antagonists, have additional beneficial effects on proteinuria that are independent of blood pressure reductions.

Effects of antihypertensive therapy on serum lipids

PURPOSE

To compare and contrast the effects of antihypertensive agents on serum lipids and blood pressure in different patient populations.

DATA SOURCES

A MEDLINE search and bibliographies from recent comprehensive reviews were used to identify trials that provided sufficient data to calculate the change in one or more serum lipid values measured before and after antihypertensive therapy.

STUDY SELECTION

474 controlled and uncontrolled clinical trials investigated the effects of 85 antihypertensive agents on lipids and blood pressure in more than 65,000 patients.

DATA EXTRACTION

Data on triglyceride and total, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol levels; blood pressure; patient characteristics; and study design.

DATA SYNTHESIS

Differences in the effects of agents, adjusted for differences in patient populations and study design, were examined using multiple linear regression analysis that was weighted by study quality and inverse variance. Diuretics caused relative increases in cholesterol levels (regression coefficient = 0.13 mmol/L; 95% CI, 0.09 to 0.18 mmol/L) that were greater with higher doses (additional effect of high dose, 0.12 mmol/L; CI, 0.04 to 0.20 mmol/L) and were worse in blacks than in nonblacks (additional effect in blacks, 0.13 mmol/L; CI, 0.01 to 0.26 mmol/L). Beta-blockers caused increases in triglyceride levels (0.35 mmol/L; CI, 0.31 to 0.39 mmol/L) that were substantially smaller for agents with intrinsic sympathomimetic activity (amelioration of beta-blocker increase, -0.21 mmol/L; CI, -0.27 to -0.16 mmol/L). When combined with cardioselectivity, beta-blockers with intrinsic sympathomimetic activity favorably affected lipids and reduced both total (-0.14 mmol/L; CI, -0.24 to -0.04 mmol/L) and LDL cholesterol levels (-0.17 mmol/L; CI, -0.28 to -0.07 mmol/L). alpha-Blockers beneficially affected total cholesterol (-0.23 mmol/L; CI, -0.28 to -0.18 mmol/L), LDL cholesterol (-0.20 mmol/L; CI, -0.25 to 0.15 mmol/L), triglycerides (-0.07 mmol/L; CI, -0.11 to -0.03 mmol/L), and, in younger persons, HDL cholesterol (0.02 mmol/L; 0.01 to 0.04 mmol/L). Converting enzyme inhibitors reduced triglycerides (-0.07 mmol/L; CI, -0.12 to -0.02 mmol/L), and, in patients with diabetes, total cholesterol (-0.22 mmol/L; CI, -0.34 to -0.10 mmol/L). Vasodilators reduced total (-0.22 mmol/l; CI, -0.30 to -0.10 mmol/L) and LDL cholesterol (-0.22 mmol/L; CI, -0.29 to -0.11 mmol/L) and increased HDL cholesterol (0.06 mmol/L; CI, 0.02 to 0.09 mmol/L).

CONCLUSION

With the exception of calcium antagonists, nearly all antihypertensive agents affect serum lipids. These effects differ among patient populations.

Screening and management of microalbuminuria in patients with diabetes mellitus: recommendations to the Scientific Advisory Board of the National Kidney Foundation from an ad hoc committee of the Council on Diabetes Mellitus of the National Kidney Foundation

All individuals with diabetes mellitus should be screened yearly with a spot urine albumin:creatinine ratio to identify those who are at increased risk for the development of complications of diabetes mellitus, including nephropathy, retinopathy, and cardiovascular disease. Once these high-risk individuals are appropriately identified, it is recommended that therapy with an angiotensin-converting enzyme (ACE) inhibitor be initiated. In addition, cardiovascular risk factors should be investigated, and when appropriate, therapeutic interventions should be initiated according to existing recommendations.

Elective cyclosporine withdrawal 1 year after renal transplantation

Whether the risks of acute rejection after elective cyclosporine (CsA) withdrawal in renal transplantation outweigh the potential benefits is unclear. We examined results for 236 patients who underwent transplantation between January 1986 and June 1991. Patients were treated with prophylactic CsA, prednisone, and azathioprine, and had grafts that functioned at least 1 year. We elected to withdraw CsA after 1 year in 192 patients who were rejection free for 12 months. Thirty-four patients elected to continue CsA. In 1988 a protocol that tapered CsA over 6 weeks was abandoned when eight (29.6%) of the first 27 patients developed acute rejection within 6 months. We then adopted a 12-week CsA taper preceded by 1 month of increased azathioprine (2.5 mg/d as tolerated) and followed by increased prednisone (30 mg/d for 1 week, 20 mg/d for 1 week, 15 mg/day for 6 months, then 15 mg/d on alternate days). With this protocol the incidence of postwithdrawal acute rejection within 6 months was reduced to 9.1% among 165 patients (P < 0.01 v 6-week taper). Actuarial 5-year graft survival (patients living with a functioning graft) was 81.7% for patients left on CsA, 88.9% for patients tapered over 6 weeks, and 81.5% for patients tapered over 12 weeks (P > 0.05). We also examined risk factors for acute rejection after CsA withdrawal using a Cox proportional hazards model and found that the relative risk of acute rejection within 6 months of taper was approximately two times greater for each DR mismatch (P < 0.001). We conclude that CsA withdrawal has not affected renal allograft survival at our center.(ABSTRACT TRUNCATED AT 250 WORDS)

The evaluation of candidates for renal transplantation. The current practice of U.S. transplant centers

The criteria for acceptance of candidates for renal transplantation varies throughout the United States. The Patient Care and Education Committee of the American Society of Transplant Physicians conducted a survey of all U.S. centers that participate in the United Network for Organ Sharing (UNOS) concerning their evaluation of adult candidates for kidney transplantation. The response to each question was examined according to the specialty of the individual who filled out the questionnaire, as well as the type of transplant center (university or private) and the size of the center. The response rate to the survey was 81% (147/182). We found the following: (1) university-based and larger centers accepted more medically complicated patients; (2) 83% noted that attendance to dialysis was an important indicator of compliance after transplantation; (3) 79% did not require preoperative blood transfusions for cadaver kidney recipients; (4) 66% set no specific upper age limit for transplantation; (5) 56% excluded patients with chronic active hepatitis in the setting of hepatitis B antigenemia; (6) 50% had no specific policy for evaluating hepatitis C antibody-positive patients, while 54% excluded the use of hepatitis C antibody-positive donors, and (7) 15% obtained coronary angiography on all diabetic patients. U.S. transplant centers have a heterogeneous approach to the evaluation of patients for renal transplantation, particularly in the areas of viral hepatitis, cardiovascular disease, and noncompliance. University-based centers and centers that perform a larger number of transplants accept more medically complicated patients.

Cholesterol synthesis inhibitors inhibit more than cholesterol synthesis

The beneficial effects of HMG-CoA reductase inhibition in models of progressive glomerular injury may not all be due to reductions in circulating lipoproteins and decreases in glomerular lipoprotein deposition. Indeed, HMG-CoA reductase inhibitors may have direct effects on glomerular mesangial cells that could explain the amelioration of renal injury. Specifically, HMG-CoA reductase inhibitors block the synthesis of isoprenoids that are necessary for mesangial cell proliferation and other important cell functions. Thus, protein isoprenylation may play a critical role in the pathogenesis and treatment of lipid-induced glomerular injury.

The renin-angiotensin system in the type II diabetic obese Zucker rat

Recently, the obese Zucker rat (OZR), an animal model of non-insulin-dependent (type II) diabetes, was shown to respond to converting enzyme inhibition with decreased albuminuria and a marked attenuation of glomerular injury. It was hypothesized that the OZR would possess low plasma renin values and an increased vascular responsiveness to angiotensin II, and therefore, the renin-angiotensin system (PRA, active renin, inactive renin, renal renin content, and plasma angiotensinogen) and vascular reactivity in OZR at 10 and 24 wk of age were investigated. PRA and renin concentration, inactive plasma renin, and renal renin content were all significantly (P < 0.05) reduced in OZR when compared with age-matched lean controls. The ratio of inactive to total renin was significantly increased in the OZR. OZR aortic ring vascular reactivity to KCl, norepinephrine, and angiotensin II was assessed. Despite essentially equal or increased contractile responses to KCl and norepinephrine at both 10 and 24 wk of age, the OZR was not more sensitive to angiotensin II and displayed a significantly reduced contractile response to angiotensin II at 24 wk of age, when compared with lean age-matched controls. It was concluded that the renal protective effect of converting enzyme inhibition in OZR, despite significantly reduced PRA and concentration, inactive plasma renin, and renal renin content, may not be due to a diabetes-induced increased vascular reactivity to angiotensin II.

Oxidative modification of low-density lipoproteins by mesangial cells

Because hypercholesterolemia and mesangial cell proliferation may be important in the pathogenesis of glomerulosclerosis, the effects of low-density lipoprotein (LDL) on human mesangial cell proliferation were evaluated. Native LDL (20 to 200 micrograms/mL) caused a dose-dependent increase in (3H)thymidine incorporation and increased mesangial cell numbers over 96 h. The mitogenic effect of LDL was partially blocked by the inhibition of cytochrome P-450, but not by the inhibition of cyclooxygenase or lipoxygenase pathways. Higher LDL concentrations (1,000 to 2,000 micrograms/mL) inhibited (3H)thymidine incorporation and reduced cell numbers, possibly as a result of the oxidative modification of LDL, indicated by an increase in thiobarbituric reactive substances. This peroxidation of LDL involved superoxide, because superoxide dismutase and butylated hydroxytoluene prevented it, whereas hydroxyl radical scavengers were without effect. Native LDL subjected to chemical oxidation by copper sulfate also inhibited mesangial cell proliferation. These results suggest that low concentrations of LDL may stimulate human mesangial cell proliferation, which may, in turn, cause the production of reactive oxygen molecules. Moreover, the oxidative modification of LDL may mediate the toxic effects of high LDL concentrations on human mesangial cells.

Lovastatin retards the progression of established glomerular disease in obese Zucker rats

Considerable experimental evidence indicates that hyperlipidemia can induce glomerular injury. The importance of lipids in the progression of established glomerular disease has not been established and is of clinical relevance because of the frequent association of lipid abnormalities with human renal disease. In the present study, 26-week-old hyperlipidemic obese Zucker rats (OZRs) with established nephropathy were treated for a period of 18 weeks with daily injections of the cholesterol synthesis inhibitor lovastatin (4 mg/kg). Compared with control OZRs treated with vehicle, lovastatin-treated OZRs had significantly (P < 0.05) lower serum cholesterol and triglyceride levels throughout the treatment period. Blood pressure and urine albumin excretion in lovastatin-treated OZRs were reduced over the first 12 weeks of therapy, but increased toward the levels in the control OZRs at the end of the protocol. After 18 weeks of therapy, the incidence of glomerulosclerosis in lovastatin-treated OZRs (23.2% +/- 5.8%) was approximately half of that in vehicle-treated OZRs (44.6% +/- 7.7%) (P < 0.05). The reduction in glomerular injury in lovastatin-treated OZRs was not associated with changes in either glomerular area or glomerular macrophage content. In separate experiments, mesangial cells were cultured from glomeruli isolated from 26-week-old proteinuric OZRs. Lovastatin (5 to 40 mumol/L) caused a significant dose-dependent inhibition of serum-stimulated mesangial cell DNA synthesis. The inhibitory effects of lovastatin were completely prevented in the presence of exogenous mevalonate (100 mumol/L). Thus, lovastatin retarded the progression of established glomerular disease in OZRs.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of hyperlipidemia in chronic progressive renal disease

Experiments in animal models suggest that correcting abnormalities in lipid metabolism could help slow the rate of functional decline in patients with chronic progressive renal disease. Circumstantial evidence in humans also suggests that lipids may play a role in the pathogenesis of glomerulosclerosis. Nevertheless, large controlled clinical trials examining the effect of lipid-lowering strategies on renal disease progression have not been carried out. However, the recent development of antilipemic agents that appear to be safe and effective in patients with renal disease should make it possible to determine whether treating hyperlipidemia will reduce the rate of renal disease progression.

Hypertension, hyperlipidemia, and renal damage

Experimental studies have demonstrated that a number of factors participate in the progression of renal disease. Systemic and glomerular hypertension have been shown to be critical factors in renal injury. Hyperlipidemia that frequently coexists with renal disease also has been suggested as an important participatory factor in nephron damage. Interestingly, both hypertension and hyperlipidemia seem to evoke glomerular growth, a factor that has also been postulated to be involved in glomerular and tubular destruction. Recently, experimental and clinical data suggest that an important interaction occurs between hyperlipidemia and hypertension. Not only do they frequently coexist, but hypertension dramatically exaggerates hyperlipidemic injury, and hyperlipidemia alters systemic and glomerular vascular production of vasoactive substances which maintain basal vascular tone. Thus, these recent observations underscore the interactive potential of the various risk factors that participate in progression of renal disease. They also suggest that multiple interventional strategies may be needed to optimally prevent progressive nephron loss.

Alterations in glomerular proteoglycan metabolism in experimental non-insulin dependent diabetes mellitus

Glomerular proteoglycans (PG) are important in modulating extracellular matrix assembly and glomerular permselectivity. In the obese Zucker rat, an experimental model of non-insulin dependent diabetes mellitus, expansion of the mesangial matrix, and microalbuminuria occur before the development of overt renal disease. The in vivo incorporation of (35S)sulfate into glomerular PG in 12-wk-old obese Zucker rats at the onset of microalbuminuria was compared with that of 12-wk-old lean Zucker rats. Specific (35S)sulfate incorporation into glomerular PG over 8 h was increased by 57% in obese rats compared with lean rats, suggesting increased PG synthesis. However, at variance with the observation in experimental models of insulin-dependent diabetes mellitus, the proportion of total glomerular (35S)PG released by heparin treatment was unchanged. Heparan sulfate (HS)-PG constituted over 60% of radiolabeled de novo synthesized glomerular PG. Similar proportions of HS-PG were extracted from the glomeruli of obese and lean rats. Isolated glomeruli spontaneously released two HS-PG, which constituted approximately 30% of total glomerular (35S)PG. On the basis of their chromatographic and electrophoretic patterns, these PG were similar in obese and lean rats. Heparin treatment of isolated glomeruli released an additional HS-PG, which appeared to be derived primarily from the glomerular extracellular matrix compartment and not from the detergent soluble cell fraction. Heparin-releasable HS-PG from both the lean and obese Zucker rats eluted at a KAV of 0.31 from Sepharose CL-6B chromatographic columns, indicating a hydrodynamic size similar to that reported for glomerular basement membrane HS-PG. However, gel electrophoresis demonstrated faster migration of the HS-PG released by heparin from the glomeruli of obese Zucker rats, suggesting increased electronegativity. Thus, early in the course of nephropathy in the obese Zucker rat, there is increased glomerular PG synthesis with no change in the proportions of the constitutively releasable and heparin-releasable HS-PG. Whether electrophoretic abnormalities of the heparin-releasable HS-PG observed in the obese rats contribute to the development of albuminuria and/or mesangial matrix expansion remains to be established.

Value of liver biopsy in the evaluation and management of chronic liver disease in renal transplant recipients

PURPOSE

Liver disease is a frequent complication in renal transplant recipients. To understand the nature and progression of hepatic disease in these patients, we performed percutaneous biopsies in 77 subjects who had chronic liver dysfunction in the posttransplant period. The purpose of the present investigation is to delineate the morphologic spectrum of chronic liver disease in the renal allograft recipients and to characterize the clinical and histologic progression of each of the different morphologic forms.

PATIENTS AND METHODS

Between 1971 and 1990, 915 patients received renal transplants at the Hennepin County Medical Center, Minneapolis, Minnesota. One hundred nineteen (13%) of them had abnormal liver function that persisted for longer than 6 months. Percutaneous liver biopsies were performed in 77 of these patients, but adequate tissue for histologic evaluation was available in only 72. After the biopsy, the clinical and histologic course of each subject was monitored in relation to the baseline hepatic morphology. To assess the predictive value of serum enzymes in diagnosing the histologic lesions, the level of serum enzymes at the time of the biopsy was correlated with the morphologic diagnosis. In addition, several clinical, biochemical, etiologic, and histologic variables were screened for their association with histologic progression to liver cirrhosis.

RESULTS

The morphologic diagnosis in the 72 specimens evaluated at baseline was as follows: fat metamorphosis in 8 (11%), chronic persistent hepatitis in 20 (28%), early chronic active hepatitis in 20 (28%), advanced chronic active hepatitis in 15 (21%), and hemosiderosis in 9 (12%). There was no statistical correlation between the serum enzyme levels and the histologic diagnosis. During a mean follow-up of 5.7 +/- 3.9 years, clinical progression to hepatic failure and death occurred in 35% of patients with early chronic active hepatitis, 55% with hemosiderosis, and 60% with advanced chronic active hepatitis. None of the patients with the morphologic diagnosis of fat metamorphosis or chronic persistent hepatitis died as a consequence of hepatic failure. Follow-up liver specimens were obtained in 34 (47%) of the original 72 subjects after a mean interval of 4.5 +/- 4.3 years. Of the 15 patients with the initial diagnosis of early chronic active hepatitis, 9 (60%) showed morphologic transition to advanced chronic active hepatitis, and in 1 of the 5 patients with hemosiderosis (20%), the lesion had resolved after successive phlebotomies. During the follow-up, 60% with early chronic active hepatitis (9 of 14), 66% with hemosiderosis (2 of 3), and 100% with advanced chronic active hepatitis (4 of 4) showed histologic progression to liver cirrhosis. On the contrary, no morphologic alterations were observed in the follow-up specimens of patients with fat metamorphosis or chronic persistent hepatitis. Of the different variables screened for their association with histologic progression, older age at transplant, female sex, and morphologic diagnosis of advanced chronic active hepatitis were found to be significant.

CONCLUSION

Histologic diagnosis can be a useful marker in predicting the course of chronic liver disease after renal transplantation. Liver biopsy should be incorporated into the evaluation and management of chronic liver disease in renal transplant recipients.

Elective cyclosporine withdrawal after renal transplantation. A meta-analysis

OBJECTIVE

To determine whether it is safe to electively discontinue cyclosporine therapy after renal transplantation.

DATA SOURCES

MEDLINE and bibliographies from recent publications.

STUDY SELECTION

Controlled trials assessing the rate of acute rejection, graft loss, and mortality after elective cyclosporine withdrawal.

DATA EXTRACTION

We compared outcomes in patients who underwent withdrawal from cyclosporine treatment with patients who were not withdrawn (part 1), and in a separate analysis (part 2), with patients who never received cyclosporine.

DATA SYNTHESIS

In part 1 of the meta-analysis, consisting of 10 randomized and seven nonrandomized trials, there was a greater combined rate of acute rejection among patients in whom cyclosporine was withdrawn compared with control patients who continued to receive cyclosporine (weighted difference in episodes per patient, 126; 95% confidence interval [CI], 0.085 to 0.167; P < .001). However, there were no differences in graft loss (weighted difference in grafts lost per patient per year, -0.009; 95% CI, -0.022 to 0.004; P = 0.19) or mortality (weighted difference in deaths per patient per year, -0.005; 95% CI, -0.016 to 0.006; P = .40) attributable to cyclosporine withdrawal. In part 2 of the meta-analysis, consisting of three randomized and three nonrandomized trials, the combined rate of graft loss for patients who were withdrawn from cyclosporine was not significantly different vs control patients who never received cyclosporine (weighted difference in grafts lost per patient per year, -0.020; 95% CI, -0.043 to 0.003; P = .08). However, when the three randomized trials were analyzed separately, graft survival was better in patients who were withdrawn from cyclosporine (weighted difference in grafts lost per patient per year, 0.0382; 95% CI, 0.0002 to 0.0762; P = .049). None of the outcomes was affected by the timing or manner of the cyclosporine withdrawal.

CONCLUSIONS

The increased incidence of acute rejection following elective cyclosporine withdrawal does not affect short-term graft or patient survival after renal transplantation. Whether long-term consequences will outweigh the benefits of elective withdrawal remains to be determined.

Elective cyclosporine withdrawal after renal transplantation. A meta-analysis

OBJECTIVE

To determine whether it is safe to electively discontinue cyclosporine therapy after renal transplantation.

DATA SOURCES

MEDLINE and bibliographies from recent publications.

STUDY SELECTION

Controlled trials assessing the rate of acute rejection, graft loss, and mortality after elective cyclosporine withdrawal.

DATA EXTRACTION

We compared outcomes in patients who underwent withdrawal from cyclosporine treatment with patients who were not withdrawn (part 1), and in a separate analysis (part 2), with patients who never received cyclosporine.

DATA SYNTHESIS

In part 1 of the meta-analysis, consisting of 10 randomized and seven nonrandomized trials, there was a greater combined rate of acute rejection among patients in whom cyclosporine was withdrawn compared with control patients who continued to receive cyclosporine (weighted difference in episodes per patient, 126; 95% confidence interval [CI], 0.085 to 0.167; P < .001). However, there were no differences in graft loss (weighted difference in grafts lost per patient per year, -0.009; 95% CI, -0.022 to 0.004; P = 0.19) or mortality (weighted difference in deaths per patient per year, -0.005; 95% CI, -0.016 to 0.006; P = .40) attributable to cyclosporine withdrawal. In part 2 of the meta-analysis, consisting of three randomized and three nonrandomized trials, the combined rate of graft loss for patients who were withdrawn from cyclosporine was not significantly different vs control patients who never received cyclosporine (weighted difference in grafts lost per patient per year, -0.020; 95% CI, -0.043 to 0.003; P = .08). However, when the three randomized trials were analyzed separately, graft survival was better in patients who were withdrawn from cyclosporine (weighted difference in grafts lost per patient per year, 0.0382; 95% CI, 0.0002 to 0.0762; P = .049). None of the outcomes was affected by the timing or manner of the cyclosporine withdrawal.

CONCLUSIONS

The increased incidence of acute rejection following elective cyclosporine withdrawal does not affect short-term graft or patient survival after renal transplantation. Whether long-term consequences will outweigh the benefits of elective withdrawal remains to be determined.

Effect of antihypertensive therapy on the kidney in patients with diabetes: a meta-regression analysis

OBJECTIVE

To assess the relative effect of different antihypertensive agents on proteinuria and renal function in patients with diabetes.

DATA SOURCES

We used MEDLINE and bibliographies in recent articles to identify studies of the effects of antihypertensive agents on renal function in patients with diabetes.

STUDY SELECTION

We selected 100 controlled and uncontrolled studies that provided data on renal function, proteinuria, or both, before and after treatment with an antihypertensive agent.

DATA EXTRACTION

Data on blood pressure, renal function, proteinuria, patient characteristics (for example, age, sex, and type of diabetes), and study design (for example, random allocation and the use of a placebo) were extracted from selected studies.

DATA SYNTHESIS

Multiple linear regression analysis indicated that angiotensin-converting enzyme (ACE) inhibitors decreased proteinuria independent of changes in blood pressure, treatment duration, and the type of diabetes or stage of nephropathy, as well as study design (P < 0.0001). Reductions in proteinuria from other antihypertensive agents could be entirely explained by changes in blood pressure. Blood pressure reduction in itself was associated with a relative increase in glomerular filtration rate (regression coefficient [+/- SE], 3.70 +/- .92 mL/min for each reduction of 10 mm Hg in mean arterial pressure; P = 0.0002); however, compared with other agents, ACE inhibitors had an additional favorable effect on glomerular filtration rate that was independent of blood pressure changes (3.41 +/- 1.71 mL/min; P = 0.05).

CONCLUSION

Angiotensin-converting enzyme inhibitors can decrease proteinuria and preserve glomerular filtration rate in patients with diabetes. These effects occur independent of changes in systemic blood pressure.