Chronic maintenance immunosuppression in renal transplantation: the unrealized goal of improved long-term outcomes

Major improvements in short-term renal transplant allograft outcomes by reductions in early graft loss due to rejection have been largely achieved with improved induction and maintenance immunosuppression drugs in the last 25 years. The hope that this would translate into improved long-term graft outcomes has not been realized. The rate of graft loss after one year has not appreciably improved over that same period. Graft losses due to immunologic, drug nephrotoxic da-mage, and death with graft function remain the principle causes of graft failure. In this review, first, the risk and benefits of currently available maintenance immunosuppression and the data regarding chronic maintenance immunosuppression strategies and long-term graft and patient outcomes will be assessed. Second, the predictive value of short-term surrogate markers for long-term graft outcomes will be reviewed and critiqued. Third, mitigating trade-offs inherent in chronic immunosuppression that impede improvement in long-term outcomes will be discussed. Finally, future ways of improving long-term graft and patient outcomes will be explored.

Elderly recipients of hepatitis C positive renal allografts can quickly develop liver disease

Our institution explored using allografts from donors with Hepatitis C virus (HCV) for elderly renal transplantation (RT). Thirteen HCV- elderly recipients were transplanted with HCV+ allografts (eD+/R-) between January 2003 and April 2009. Ninety HCV- elderly recipients of HCV- allografts (eD-/R-), eight HCV+ recipients of HCV+ allografts (D+/R+) and thirteen HCV+ recipients of HCV- allografts (D-/R+) were also transplanted. Median follow-up was 1.5 (range 0.8-5) years. Seven eD+/R- developed a positive HCV viral load and six had elevated liver transaminases with evidence of hepatitis on biopsy. Overall, eD+/R- survival was 46% while the eD-/R- survival was 85% (P = 0.003). Seven eD+/R- died during follow-up. Causes included multi-organ failure and sepsis (n = 4), cancer (n = 1), failure-to-thrive (n = 1) and surgical complications (n = 1). One eD+/R- died from causes directly related to HCV infection. In conclusion, multiple eD+/R- quickly developed HCV-related liver disease and infections were a frequent cause of morbidity and mortality.

Kidney and pancreas transplantation in the United States, 1998-2007: access for patients with diabetes and end-stage renal disease

Although the number of candidates on the kidney transplant waiting list at year-end rose from 40 825 to 76 070 (86%) between 1998 and 2007, recent growth principally reflects increases in the number of patients in inactive status. The number of active patients increased by 'only' 4510 between 2002 and 2007, from 44 263 to 48 773. There were 6037 living donor and 10 082 deceased donor kidney transplants in 2007. Patient and allograft survival was best for recipients of living donor kidneys, least for expanded criteria donor (ECD) deceased donor kidneys, and intermediate for non-ECD deceased donor kidneys. The total number of pancreas transplants peaked at 1484 in 2004 and has since declined to 1331. Among pancreas recipients, those with simultaneous pancreas-kidney (SPK) transplants experienced the best pancreas graft survival rates: 86% at 1 year and 53% at 10 years. Between 1998 and 2006, among diabetic patients with end-stage renal disease (ESRD) who were under the age of 50 years, 23% of all and 62% of those waitlisted received a kidney-alone or SPK transplant. In contrast, 6% of diabetic patients aged 50-75 years with ESRD were transplanted, representing 46% of those waitlisted from this cohort. Access to kidney-alone or SPK transplantation varies widely by state.

Cardiovascular events following renal transplantation: role of traditional and transplant-specific risk factors

Cardiovascular mortality is increased in transplant recipients. However, studies including non-fatal events are critical to assess the burden of disease and to identify novel risk factors. We described the incidence of fatal and non-fatal events, and explored associations and interactions among traditional and transplant-specific risk factors and cardiovascular events (CVE) in a cohort of 922 patients transplanted between 1993 and 1998. One hundred and seventy-six patients experienced 201 CVE (111 cardiac, 48 cerebrovascular, 42 peripheral-vascular). Most CVE were non-fatal. Factors associated with cardiac events were (adjusted hazard ratios) tobacco (3.53; P<0.001), obesity (2.92; P<0.001), diabetes (2.63; P<0.001), multiple rejections (2.19; P=0.008), prior CVE (2.0; P=0.004), dialysis >1 year (1.91; P=0.007), and overweight status (1.68; P=0.04); with cerebrovascular events: diabetes and peritoneal dialysis (11.95; P<0.001), age >45 (6.77; P<0.001), diabetes (4.87; P<0.001), prior CVE (3.73; P<0.001), creatinine >141 micromol/l (3.16; P=0.001), peritoneal dialysis (3.06; P=0.027), and obesity (0.32; P=0.046); with peripheral-vascular events: diabetes (8.48; P<0.001), tobacco and cytomegalovirus (3.88; P<0.001), age >45 (2.31; P=0.019), and prior CVE (2.25; P=0.016); with mortality: tobacco and deceased-donor (3.52; P<0.001), age >45 (1.81; P=0.002), diabetes (1.76; P=0.002), pulse pressure (1.64; P=0.029), prior CVE (1.52; P=0.04), and dialysis >1 year (1.47; P=0.04). The majority of CVE post-transplant were non-fatal. Previous CVE was strongly associated with CVE post-transplant. Interactions among transplant-specific and traditional risks impacted significantly the incidence of CVE. Modifiable factors such as duration of dialysis, deceased-donor transplantation, and acute rejection should be viewed as cardiovascular risks.

Effect of sodium chloride, enalapril, and losartan on the development of polycystic kidney disease in Han:SPRD rats

We found that the administration of an angiotensin I-converting enzyme inhibitor and sodium chloride loading lessen the development of renal cystic disease induced by 2-amino-4-5-diphenylthiazole in rats. To determine whether similar effects could be observed in an autosomal dominant model of polycystic kidney disease, heterozygous cystic (Cy/+) and homozygous normal (+/+) Han:SPRD rats were divided into experimental groups at 3 weeks of age. The first study included four groups receiving enalapril (50 mg/L), losartan (400 mg/L), hydralazine (80 mg/L), or no drug in their drinking water. The second study included four groups fed a sodium-deficient diet or the same diet supplemented with 0.25%, 0.6%, or 3.3% sodium chloride. The Cy/+ rats receiving enalapril had lower kidney weights and histologic scores than those in the control group, and lower kidney weights, plasma creatinines, and histologic scores than those in the hydralazine group. The Cy/+ rats receiving losartan had lower plasma creatinines and histologic scores than those in the control and hydralazine treatment groups. A sodium-deficient diet markedly blunted the growth of the animals and the development of cystic disease. Increases in the sodium content of the diet in the other three groups were accompanied by higher relative kidney weights and histology scores, while the levels of plasma creatinine were not significantly different. Regression of the cystic disease was observed between 3 and 4 months of age. These results indicate that the development of autosomal dominant polycystic kidney disease in the rat can be modulated by pharmacologic and nutritional factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal ammonia in autosomal dominant polycystic kidney disease

Recent studies have suggested that defective medullary trapping of ammonia underlies the acidosis associated with renal failure and sets in motion maladaptive compensatory mechanisms that contribute to the progression of renal disease. Since a renal concentrating defect is an early functional abnormality in autosomal dominant polycystic kidney disease (ADPKD), defective medullary trapping and urinary excretion of ammonia may also occur early and have important pathophysiological consequences. The urinary pH and excretions of ammonia, titratable acid, and bicarbonate, were measured during a 24-hour baseline period and following the administration of ammonium chloride (100 mg/kg body wt) in ADPKD patients with normal glomerular filtration rate and in age- and gender-matched healthy control subjects. The distal nephron hydrogen ion secretory capacity was assessed during a bicarbonate infusion. Ammonia, sodium, pH, C3dg, and C5b-9 were measured in cyst fluid samples. The excretion rates of ammonia during the 24-hour baseline period and following the administration of ammonium chloride were significantly lower, and the relationship of ammonia excretion to urinary pH was significantly shifted downward in ADPKD. No difference in the increment of urinary pCO2 (delta pCO2) or the peripheral blood-urine pCO2 gradient (U-B pCO2) between ADPKD patients and control subjects was detected during a sodium bicarbonate infusion. Calculated concentrations of free-base ammonia in cyst fluid samples exceeded those calculated from reported concentrations of ammonia in renal venous blood of normal subjects. C3dg and C5b-9 were detected in some cyst fluids. The urinary excretion of ammonia is reduced in ADPKD patients with normal glomerular filtration rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal cell carcinoma in autosomal dominant polycystic kidney disease

To provide information on the clinical presentation, diagnosis, pathology, and biologic behavior of renal cell carcinoma in patients with autosomal dominant polycystic kidney disease (ADPKD), three cases seen at this institution between 1955 and 1992, as well as the cases reported in the literature, were reviewed in detail. No male predominance was observed (12 men, 13 women) in the 25 patients who met the inclusion criteria. The age of presentation was earlier than that seen in the general population (45 versus 61 yr). Fever, night sweats, and weight loss were prominent at presentation. Fever is a more common presenting symptom of renal cell carcinoma in ADPKD (32%) than in the general population (7%). Twenty percent of the patients had metastatic disease at presentation. Even with computed tomography and magnetic resonance, the diagnosis was difficult and often delayed, and the accumulation of 111In-labeled white blood cells can wrongly suggest a cyst infection. Renal cell carcinoma in ADPKD is more often concurrently bilateral (12 versus 1 to 5%), multicentric (28 versus 6%), and sarcomatoid in type (33 versus 1 to 5%) than in the general population. Because previous studies have failed to demonstrate a higher prevalence of renal cell carcinoma in ADPKD, this information suggests either a malignant potential restricted to a small subset of patients with this disease or an alteration in the biologic behavior of renal cell carcinoma when it develops in the setting of ADPKD.

Idiopathic retroperitoneal fibrosis

Herein is described a case report of urinary tract obstruction due to idiopathic retroperitoneal fibrosis (IRF) in a 43-year-old man. Recent studies suggest that IRF fits into the broader pathologic heading of chronic periaortitis. Although there may be more than one pathophysiologic mechanism, growing evidence suggests that many cases of IRF are due to an autoallergic reaction to lipid material in the atheromatous aorta. Computed tomographic scanning has supplanted excretory and retrograde urography in the diagnosis of this condition. Ureterolysis and steroids remain the mainstays in the treatment of IRF. Even after successful decompression of urinary obstruction, long-term follow-up is required in these patients because of the possibility of other complications such as vena caval or duodenal obstruction.

Heparin therapy for recent transient focal cerebral ischemia

The Mayo Clinic medical records and records linkage system were used to identify stroke-free residents of Rochester, Minnesota, who were examined within 30 days after the first transient cerebral ischemic attack (TIA) during the period 1955 through 1979. The patients were divided into two groups: those given heparin within 30 days after the first attack and those not given heparin. Death, stroke, and either stroke or TIA were separate endpoints in Kaplan-Meier analyses of data from the day of initial examination through the 30th day thereafter. The probabilities of survival, survival free from stroke, and survival free from TIA for the heparin-treated group were not significantly different from those probabilities for the comparison group. The rate of hemorrhagic complications was 3.2 per 100 person-days of heparin therapy. Retroperitoneal hemorrhage, the most serious complication, was the cause of one death and one case of femoral neuropathy.