Immunosuppressive drugs in pregnancy

Successful pregnancies are now common in female organ transplant recipients. Despite high rates of success, pregnancy in an organ transplant recipient should be managed as a high-risk condition with emphasis on prevention and prompt treatment of rejection episodes. The number of immunosuppressive drugs and drug combinations has increased in recent years. Data accrued by a national registry indicate that pregnancy is generally successful in patients maintained on some combination of cyclosporine, azathioprine, and steroids. Relatively little information is available regarding the safety of some of the newer immunosuppressive agents in pregnancy. Until additional information is collected, transplant physicians and obstetricians must balance the efficacy of immunosuppressants in preventing allograft rejection in the mother against possible adverse drug reactions in both the mother and fetus.

Long-term renal function in type I diabetics after kidney or kidney-pancreas transplantation: influence of number, timing, and treatment of acute rejection episodes

BACKGROUND

Previous studies comparing renal function in diabetic subjects receiving either a kidney or kidney-pancreas transplant generally have indicated no differences; however, these studies have been limited by inclusion of either a small number of patients or selected patients followed for relatively short periods of time.

METHODS

To compare long-term renal function and factors affecting renal function in type I diabetic patients receiving either kidney or kidney-pancreas transplants, the slopes of regression lines generated by plotting the reciprocal of serum creatinine (1/Cr) versus time were measured in 109 consecutive patients followed for at least 12 and up to 102 months after transplantation. Multivariate analyses included linear regression using the slope of 1/Cr versus time as the dependent variable and logistic regression using a positive or negative slope as the dependent variable.

RESULTS

Significant differences between kidney-pancreas (n=64) and kidney recipients (n=45) included a smaller proportion of African-Americans, lower rates of HLA matching, lower levels of panel-reactive antibodies, shorter cold ischemia times, a lower incidence of delayed graft function, and a higher incidence of acute renal allograft rejection episodes in the kidney-pancreas group. Trough cyclosporine blood levels were significantly higher in the kidney-pancreas group for the first 12 posttransplant months. The slopes of 1/Cr versus time were negative in each group with a trend toward a more negative slope in the kidney-pancreas group. Multivariate analyses indicated that a concomitant pancreas allograft did not influence long-term renal function. The total number of renal rejection episodes was the best independent predictor of a negative slope of 1/Cr versus time. However, use of OKT3 for the treatment of rejection within the first 3 months of transplantation exerted a surprisingly beneficial effect on long-term renal function, a phenomenon that was most apparent in the kidney-alone group.

CONCLUSIONS

The frequency and timing of acute rejection episodes are more important than the influence of a simultaneously transplanted pancreatic allograft in determining long-term function of the transplanted kidney. A concerning trend toward late deterioration of renal function in kidney-pancreas recipients suggests that the benefits of sustained euglycemia, shorter cold ischemia times, lower rates of sensitization, and early use of OKT3 ultimately may be outweighed by the negative effects of more frequent renal rejection episodes.

Influence of steroid withdrawal on proteinuria in renal allograft recipients

The ratio of urine protein/urine creatinine in spot urine specimens was measured to determine the influence of steroid withdrawal and other clinical variables on urinary protein excretion in 135 primary renal transplant recipients, including 73 patients in whom steroid withdrawal was never attempted and 62 patients in whom steroid withdrawal was attempted at various times following transplantation. Both univariate and multivariate analyses showed that steroid withdrawal per se did not directly influence proteinuria. However, patients who renewed steroid therapy because of acute allograft rejection following attempted steroid withdrawal exhibited significantly more proteinuria than was encountered either in patients who remained steroid-free or in those for whom steroid withdrawal was never attempted. This study suggests that steroid withdrawal itself does not lead to proteinuria, however, acute rejection following steroid withdrawal clearly accelerates urinary protein excretion that may be the harbinger of chronic allograft rejection.

Optimizing end-stage renal disease therapy for the patient with diabetes mellitus

Patients with diabetes represent the fastest growing segment of the end-stage renal disease (ESRD) population, which itself is growing at a rate of approximately 10% per year. The most recent report of the United States Renal Data System (USRDS) shows a prevalence of diabetes among patients with ESRD of 27.3% (59,403 of 217,479) and an incidence of 33.6% (19,013 of the 56,610). The majority of patients with ESRD secondary to diabetes (67.7%) are treated by hemodialysis, 13.2% by peritoneal dialysis, and 19.1% have functioning renal transplants. The number of patients over 60 years of age has increased steadily. Parallel with this increase, the percentage of patients with one or more comorbid conditions increased from 66% to 85% in patients with diabetes and from 57% to 66% in patients without diabetes. The relative risk of death in patients with diabetes is markedly increased and is further exacerbated in patients with poor nutritional status. Although diabetes is the most common primary disease associated with death in the ESRD population, the mortality for patients with ESRD secondary to diabetes has decreased from 46% in 1982 to 29% in 1993. Patients with ESRD from diabetes challenge the nephrologist because they have the greatest number of comorbid conditions, the highest levels of physical dysfunction, and the greatest dependency in activities of daily living. The goal of therapy is to improve quality of life, as well as reduce mortality. Patients with diabetes experience improved survival after either kidney transplant or enhanced Kt/V on dialysis. Therefore, the most important therapeutic intervention is to maximize renal replacement therapy (either by transplantation or by providing levels of dialysis adequacy higher than previously recommended). In addition, attention to several basic principles helps to guide therapy; control of hypertension, control of hyperglycemia, control of lipid abnormalities, treatment of malnutrition, and attention to the effects of erythropoietin. Advanced glycation and products (AGEs) have been proposed as new "uremic toxins", because of their pathogenetic association with a variety of vascular and morbid complications. There is sound experimental evidence to suggest that reducing the accumulation of these products to normal levels may prevent diabetic complications. Better understanding of the nature of the relationship between formation and removal is needed to direct therapeutic interventions towards adequate control of the accumulation of AGEs in patients with renal failure, with or without diabetes.

Renal function following conversion from Sandimmune to Neoral in stable renal transplant recipients

Conversion of stable renal transplant patients from Sandimmune to Neoral may pose a risk of short-term nephrotoxicity. Serial serum creatinine concentrations were measured in 141 kidney and simultaneous kidney-pancreas transplant recipients converted from Sandimmune to Neoral on a 1:1 dosing basis and followed for up to 11 months. Following conversion, cyclosporine dose was reduced in 74% of patients with a mean dose reduction of 22.6% for the entire cohort. Serum creatinine concentrations transiently increased to more than 30% above baseline in 48% of patients and remained more than 30% above baseline in 16% of patients. Multivariate analyses suggested that acute rejection, maintenance steroid therapy, young age, Sandimmune dose prior to conversion, and an increment in trough cyclosporine levels after conversion were positive predictors of renal insufficiency following conversion. Lower doses of Neoral should be considered at the time of conversion to minimize nephrotoxicity.

Acute intermittent porphyria: clinicopathologic correlation. Report of a case and review of the literature

Acute intermittent porphyria (AIP), an autosomal dominant disorder, results from a deficiency of the enzyme hydroxymethylbilane synthase. Despite important advances in the characterization of AIP, the pathophysiology of the neurologic manifestations is not clearly understood. We present a patient with AIP followed for 31 years with multiple episodes of hyponatremia during AIP exacerbations. We discuss the clinicopathologic correlation and possible explanations for the morphologic findings, including discrete hypothalamic changes.

Renal transplantation using a kidney with a large benign cyst

We report a case in which a living donor kidney that contained a large benign cyst was successfully transplanted between a mother and her daughter. The donor, a 53-year-old woman, had good renal function, but her right kidney contained a large 4-cm cyst that had a benign appearance on computed tomography. At operation the cyst was proven to be benign by frozen-section histological examination and the transplant was performed. Both donor and recipient continue to enjoy satisfactory renal function 3 years after transplantation. A review of the literature regarding renal cysts and management strategies for use of cystic kidneys in transplantation are presented.

Safety and tolerability of cyclosporine microemulsion versus cyclosporine: two-year data in primary renal allograft recipients: a report of the Neoral Study Group

BACKGROUND

The new microemulsion formulation of cyclosporine (CsA-ME) is more bioavailable than cyclosporine (CsA) in de novo renal transplant patients. Therefore, it was of interest to compare the safety profile of each formulation in such patients.

METHODS

In a multicenter, double-blind, parallel-group study, 101 renal transplant recipients were randomized after transplantation to receive either CsA (n=50) or CsA-ME (n=51) capsules twice daily for 2 years. Of these patients, 54 (CsA, n=26; CsA-ME, n=28) completed 1 year of the study and entered the second-year, double-blind extension. Initial dose at the time of transplantation was 5 mg/kg b.i.d.; doses were titrated to target trough levels.

METHODS

The mean (+/- SD) doses at the end of 2 years were 4.6 +/- 1.8 and 3.8 +/- 1.1 mg/kg per day for CsA- and CsA-ME-treated patients, respectively. The mean (+/- SD) CsA trough levels at end point were 187 +/- 63 and 210 +/- 95 ng/ml for CsA- and CsA-ME-treated patients, respectively. At least one adverse event was reported by 25/26 (96%) of CsA- and 27/28 (96%) of CsA-ME-treated patients. No patient discontinued the study because of adverse events. No deaths occurred during the study. Renal function, as measured by serum creatinine levels, and blood pressure were comparable over time in both treatment groups.

CONCLUSIONS

There was no significant difference in safety and tolerability between CsA- and CsA-ME-treated kidney recipients for 2 years after transplantation.

Effects of fluvastatin on hyperlipidemia after renal transplantation: influence of steroid therapy

OBJECTIVE

To assess the efficacy and safety of fluvastatin in hypercholesterolemic, cyclosporine-treated, renal transplant recipients, and to determine whether concomitant steroid therapy in such patients alters the lipid-lowering effects of fluvastatin.

DESIGN

An open-label, prospective, parallel study was performed in 20 cyclosporine-treated renal transplant recipients with hypercholesterolemia defined by a low-density lipoprotein (LDL) concentration greater than 160 mg/dL or a total cholesterol/high-density lipoprotein (HDL) concentration ratio greater than 5.0. Lipid profiles were measured before and 1 month after treatment with fluvastatin 20 mg/d. Lipid profiles in a group of patients receiving concomitant therapy with prednisone (n = 12) were compared with those of patients who had not received steroids for at least 6 months (n = 8).

SETTING

The Renal Transplant Clinic at University Hospitals of Cleveland.

MAIN OUTCOME MEASURES

The main outcome measures were serum concentrations of total cholesterol, LDL, HDL, and triglycerides. Treatment failure was defined by LDL concentrations persistently above 160 mg/dL after 1 month of fluvastatin therapy. Safety was assessed clinically and by serial measurements of liver enzymes and creatine phosphokinase.

RESULTS

LDL concentrations decreased significantly in both the steroid-treated and steroid-free groups after 1 month of fluvastatin therapy. There was no significant change in HDL concentrations or serum triglycerides in either group. Treatment failure was more common in patients receiving steroids (4/12 patients) than in steroid-free patients (1/8 patients). After 1 month of therapy, LDL cholesterol was significantly lower in the steroid-free group (126 +/- 18 mg/dL) than in the steroid-treated group (147 +/- 23 mg/dL) (p < 0.05). There was no clinical or laboratory evidence of myonecrosis in either group.

CONCLUSIONS

Low dosages of fluvastatin appear to be safe in cyclosporine-treated renal transplant recipients. Steroid-free patients exhibit a response to fluvastatin that is qualitatively similar to that of steroid-treated patients, consisting of a significant decrease in LDL concentrations and no change in HDL or serum triglyceride concentrations.

Disparate changes in plasma and tissue pentosidine levels after kidney and kidney-pancreas transplantation

The advanced glycation end-product, pentosidine, was measured in plasma proteins and skin collagen before and after kidney and kidney-pancreas transplantation in order to determine the relationship between plasma and tissue levels and to characterize the pattern of change in pentosidine levels after correction of hyperglycemia and/or renal failure. The content of pentosidine in skin collagen was higher than that in plasma proteins both before and after transplantation. However, there was no correlation between plasma and skin pentosidine levels. Prior to transplantation, the content of pentosidine in skin collagen was related to the duration of dialytic therapy, presence of diabetes mellitus, age, and female gender. Following transplantation, plasma pentosidine levels were inversely correlated with glomerular filtration rate (r = 0.64; p < 0.01). While plasma pentosidine levels consistently decreased after transplantation, levels in skin collagen increased in 10 of 13 patients, including 5 of 6 recipients of kidney-pancreas transplants. Our results indicate that tissue levels of pentosidine persist for long periods of time after kidney or kidney-pancreas transplantation, despite consistent decreases in levels measured in plasma proteins. The observed increase in tissue pentosidine levels in a majority of patients suggests that formation of advanced glycation end-products may continue after otherwise successful kidney or kidney-pancreas transplantation.

Evaluation of enalapril/diltiazem ER in hypertensive patients with coexisting renal dysfunction. Enalapril/Diltiazem ER in Hypertensive Renal Disease Group

Both enalapril and long-acting diltiazem have been shown to effectively lower blood pressure (BP) in hypertensive patients. Furthermore, in clinical studies, these two agents provided beneficial renal effects in these patients when administered on a long-term basis. A combination of enalapril/diltiazem ER was evaluated in 62 patients with Stage 1-3 hypertension and coexisting renal disease. This trial used a multicenter, randomized, double-blind, parallel group design. The study consisted of a 12-week double-blind phase followed by a 6-month open-label extension phase. The combination of enalapril/diltiazem ER was shown to reduce BP following both short-term and long-term treatment phases. Patients in Renal Group I (creatinine clearance CrCl): 30-59 ml/min/1.73 m2) had decreases of -18/-16 and -25/-20 mm Hg after 12 weeks and 9 months of therapy, respectively. Those in Renal Group II (CrCl: 10-29 ml/min/1.73 m2) had similar decreases of -23/-18 and -23/-19 mm Hg at these time points. The adverse events, in both phases, were those associated with the respective monotherapies. A reduction in CrCl with a coincident decrease in proteinuria was noted for both renal groups. The combination of enalapril/diltiazem ER lowered BP and was generally well tolerated by the patients. The combination of these two agents should improve the management of hypertensive patients.

The safety and tolerability of cyclosporine emulsion versus cyclosporine in a randomized, double-blind comparison in primary renal allograft recipients. The Neoral Study Group

A 12-week, randomized, double-blind, multicenter pharmacokinetics study was conducted to compare the clinical safety and tolerability of cyclosporine capsules and oral solution for microemulsion and cyclosporine in 101 primary renal transplant recipients Cyclosporine emulsion has more complete absorption and improved bioavailability compared with cyclosporine, and dosing of both cyclosporine formulations was adjusted to achieve comparable whole-blood trough levels. Mean serum creatinine values were higher in the cyclosporine emulsion group at baseline, 8, and 12 weeks (P<0.05). The incidence of acute rejection was similar in both treatment groups although fewer patients required monoclonal antibody therapy in the cyclosporine group (31% vs. 82%, respectively). Despite the increased bioavailability of cyclosporine emulsion, no significant differences in the incidence of adverse events were observed; the safety, tolerability, and efficacy of cyclosporine emulsion and cyclosporine were comparable.

Pancreas transplantation for diabetes mellitus

Pancreas transplantation has become a viable option for the patient wi th insulin-dependent diabetes mellitus with progressive renal failure. The most common type of pancreas transplantation is a simultaneous pancreas and kidney transplantation performed from a single cadaver donor (SPK). The next most common is pancreas transplantation after successful kidney transplantation (PAK). A few centers are performing pancreas transplantation alone (PTA) in diabetic recipients without renal disease but who have significant complications from their diabetes. Pancreas transplantation is associated with a higher morbidity than kidney transplantation alone. Most pancreas transplantation centers report a significant increase in acute rejection, which can lead to increased hospitalization and risk of opportunistic infection. In addition, the early era of pancreas transplantation was associated with significant surgical complications. However, with bladder drainage of the pancreas exocrine secretions, the surgical complication rate has decreased significantly. Despite medical and surgical complications, the overall results for pancreas transplantation are excellent, with 1 -year graft survival of 75% for SPK transplantations and 48% for PAK and PTA transplant recipients. The effects of a pancreas transplantation on the secondary complications of diabetes have been studied extensively. Most studies have shown a modest improvement in secondary complications with the exception of diabetic retinopathy. The major benefit of pancreas transplantation appears to be enhanced quality of life for patients successfully transplanted. For these reasons, the Kidney-Pancreas Committee of the American Society of Transplant Physicians believes the current results of pancreas-kidney transplantation justify its use as a valid option for insulin-dependent diabetic transplant recipients.

Determinants of long-term allograft function following steroid withdrawal in renal transplant recipients

We retrospectively measured changes in serum creatinine concentration as estimates of changes in renal function in 96 renal transplant recipients who were withdrawn from steroid therapy, maintained on cyclosporine and azathioprine, and followed for 1 to 5 years. Multivariate analyses were used to assess the influence of cyclosporine dose and blood levels, azathioprine dose, age, sex, race, diabetes, HLA match and mismatch, PRA, and history of rejection following steroid withdrawal on long-term allograft function. Results indicate that acute rejection and cyclosporine dose are the major factors influencing long-term renal function after steroid withdrawal. In this setting, there is an inverse relationship between cyclosporine dose and serum creatinine concentration for up to 5 years. Optimal renal function is achieved in patients receiving more than 5.5 mg/kg of cyclosporine per day at the time of steroid withdrawal.

Influence of dialysis modality on plasma and tissue concentrations of pentosidine in patients with end-stage renal disease

Plasma and tissue concentrations of pentose-derived glycation end-products ("pentosidine") are elevated in diabetic patients with normal renal function and in both diabetic and nondiabetic patients with end-stage renal disease. To determine the influence of dialysis modality and other clinical variables on the accumulation of pentosidine, we used high-performance liquid chromatography to measure this advanced glycation end-product in plasma, skin, and peritoneal samples obtained from 65 hemodialysis and 45 peritoneal dialysis patients. Plasma pentosidine levels were significantly lower in peritoneal dialysis patients. Concentrations of pentosidine in skin were similar in the two groups. In contrast, peritoneal concentrations of pentosidine were significantly higher in the patients maintained on peritoneal dialysis. Our results demonstrate that dialysis modality influences the plasma and tissue distribution of pentosidine. Compared with hemodialysis, peritoneal dialysis is associated with lower levels of this glycation end-product in plasma, but with higher levels in the peritoneum. The mechanisms accounting for lower circulating levels of pentosidine in peritoneal dialysis patients remain to be determined. Higher levels in peritoneal tissues may reflect chronic exposure to the high concentrations of glucose in peritoneal dialysate.

Factors influencing vertebral bone density after renal transplantation

In an effort to determine the influence of immunosuppressive therapy and other clinical variables on posttransplant osteopenia, vertebral bone density was measured at least 6 months after transplantation in 65 adult primary renal transplant recipients receiving a variety of immunosuppressive regimens. Fifteen of the 65 patients (23%) had vertebral bone densities below a fracture threshold of 1.0 g hydroxyapatite/cm2. Multivariate analyses indicated that cumulative steroid dose and female gender were the major independent predictors of low vertebral bone density. In women, postmenopausal status also was associated with osteopenia. There was no correlation between cumulative cyclosporine dose and bone density. Results of this study indicate that posttransplant osteopenia is common in renal transplant recipients, including those treated with CsA. Although CsA has allowed the use of lower cumulative doses of steroids, concomitant steroid therapy remains the preeminent factor accounting for loss of bone density.

Metastatic calcification of the true vocal cords as a cause of hoarseness

Visceral soft tissue calcification is common in patients with end-stage renal disease. However, metastatic calcification of the true vocal cords has not been described. We present a patient with chronic renal failure and hoarseness in whom an exophytic true vocal cord mass was diagnosed as a metastatic calcification.

Posttransplant hyperlipidemia: the treatment dilemma

Hyperlipidemia occurs in the majority of renal transplant recipients and may play an important role in the development of posttransplant cardiovascular disease. Although many clinical factors are associated with posttransplant hyperlipidemia, corticosteroids and cyclosporine clearly play key pathogenetic roles. Aside from cautious reduction of immunosuppression and appropriate dietary restrictions, therapeutic strategies for the management of posttransplant hyperlipidemia are limited, in part, due to special pharmacologic considerations in transplant recipients receiving cyclosporine. Based on recent studies suggesting that low doses of 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase inhibitors are safe and effective, these agents have emerged as the drugs of first choice in the pharmacologic treatment of posttransplant hypercholesterolemia. Considering the increasing importance of cardiovascular disorders as major causes of posttransplant morbidity and mortality, additional studies are warranted to delineate the relationship between posttransplant hyperlipidemia and posttransplant cardiovascular disease, and to find safe and effective strategies for reducing lipid levels after renal transplantation.

Steroid withdrawal after renal transplantation

Corticosteroid therapy following renal transplantation has been a mainstay in immunosuppression for three decades despite the numerous side effects associated with its use. Because of these, steroid-free immunosuppression has been a persisting goal in clinical transplantation. We have demonstrated that early (within the 1st week of transplantation) steroid withdrawal in renal transplantation, although safe a measured by ultimate graft survival, is associated with an increased rate of severe rejection episodes. Late steroid withdrawal (6 months or later), however, could be successfully achieved in the majority of patients when maintenance therapy consisted of azathioprine and cyclosporine. Immunologic and hematologic consequences included rejection episodes (25%), decreased cyclosporine requirement (higher levels with lower doses), and leukopenia that required azathioprine dosage reduction. More importantly, metabolic consequences included reduced incidence of hypertension, improved glycemic control, and reduced total levels of serum lipids. In regard to the latter, however, nondiabetic patients experienced a rise in their total/HDL cholesterol ratios because of a selective decrease in HDL cholesterol while diabetic patients experienced significant lowering of all lipid levels. All patients looked and felt better after elimination of chronic steroid therapy. The long-term consequences of steroid-free cyclosporine-based immunosuppression on graft survival in renal transplantation are not yet clear.