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Query: UMLS:C0022116 (
ischemia
)
91,303
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Post-transplant cure tubular necrosis (ATN) represents the most frequent cause of delayed graft function in the immediate post-transplant period. Several causes have been associated with the development of post-transplant ATN such as donor and recipient ages, cold-warm
ischemia
times, HLA mismatches, and postoperative hypotension. In the present study, we retrospectively evaluated the role of secondary hyperparathyroidism and high parathyroid hormone (PTHi) blood levels in the development of post-transplant ATN. One hundred patients submitted to cadaveric renal transplant between January 1992 and March 1993 in our unit were included. Twenty-seven patients (27%) developed post-transplant ATN and seventy-three (73%) did not. Post-transplant ATN was significantly associated with gender (p < 0.01), recipient age (p < 0.01), number of transplantations (p < 0.01), time on hemodialysis (p < 0.001), cold ischemic time (p < 0.05) and PTHi levels (p < 0.001). The bivariate and multivariate statistical analyses demonstrated that the development of post-transplant ATN was significantly more frequent in females; retransplanted patients, patients with a time on dialysis of more than 5 years, recipients over 60 years old, patients with a PTHi blood level higher than 240 pg/ml (4 times normal level) and a cold
ischemia
time of more than 18 h. Based on these results, we conclude that high PTHi blood levels in the renal transplant recipients represent a relevant factor in the development of post-transplant ATN. The administration of intravenous pulsed of 1,25(OH)2D3 and/or a calcium channel blocker in the perioperative period could be useful to decrease the incidence and severity of post-transplant ATN in these patients.
Nephron
1996
PMID:Role of secondary hyperparathyroidism in the development of post-transplant acute tubular necrosis. 874 60
Nonocclusive mesenteric infarction has recently been diagnosed with increasing frequency in dialysis patients. Although most reports have concerned patients on hemodialysis, the condition has also been reported to occur in patients on continuous ambulatory peritoneal dialysis. This report describes such a case developing in a woman whose end-stage renal failure was due to adult polycystic kidney disease. Associated predisposing factors were the presence of orthostatic hypoxemia, postural hypotension and extensive atheromatous changes of the abdominal aorta. In keeping with the known difficulty of establishing the diagnosis of mesenteric
ischemia
, the diagnosis in our patient was also delayed. She was initially thought to suffer from an episode of peritonitis and/or colonic perforation secondary to the performance of a cleansing enema. Only upon showing pneumatosis coli of the right colon on abdominal computerized tomography was the correct diagnosis made. Laparotomy revealed extensive necrosis of the ascending and transverse colon. A total colectomy and ileorectal anastomosis were performed. The patient died on the 17th day following surgery. This case serves to illustrate that mesenteric infarction should be considered in predisposed patients on continuous ambulatory peritoneal dialysis. The presence of peritonitis may mask the underlying pathology and waylay the unwary physician.
Nephron
1996
PMID:Nonocclusive mesenteric infarction in continuous ambulatory peritoneal dialysis. 889 66
Sixteen kidney transplant (KT) patients (10 men, 6 women, aged 49 +/- 10 years) with chronic hepatitis C alpha-interferon (IFN-alpha) therapy (Intron A, Schering Plough) at a dose of 3 x 10(6) units subcutaneously 3 times a week. The treatment was scheduled for 24 consecutive weeks. Each patient had had stable renal function for at least 12 months prior to IFN-alpha therapy (mean serum creatinine, SCr, 121 +/- 38 mmol/l). Fourteen patients were receiving cyclosporin-A (CsA)-based immunosuppression and 2 patients were on conventional therapy. The patients' SCr was checked every 2 weeks while on IFN-alpha, or weekly if it increased more than 15% from baseline. IFN-alpha was withdrawn if SCr increased more than 25% from baseline, in which case a kidney biopsy was performed. Six patients experienced either acute (n = 5) or subacute (n = 1) renal failure within 7-24 weeks after the onset of IFN-alpha therapy. Their mean SCr increased from 105 +/- 31 to 207 +/- 63 mmol/l (p = 0.02) with de novo proteinuria in 1 case (1 g/day) and an increase in preexisting proteinuria in 2. The other 3 patients did not develop proteinuria. In each case, histological study showed diffuse interstitial edema associated with dilation of the peritubular capillaries, whereas mild inflammatory infiltrates were present in only 3 cases and mild glomerular lesions were not always found (glomerular
ischemia
, mesangial hypertrophy). There were no vascular lesions. IFN-alpha was withdrawn in these 6 patients, in association with methylprednisolone pulses in 5 cases. Renal function improved in 2 cases, stabilized in 1 and progressed to end-stage renal failure in 3 within 4-12 months. Four of these patients had iterative renal biopsies which showed diffuse interstitial fibrosis in each case. The patients who developed renal failure did not statistically differ at the start of the study from those who did not, with respect to the following: baseline immunosuppression, HLA matching, total peripheral blood lymphocyte count or peripheral blood lymphocyte subtypes. IFN-alpha therapy was associated with acute or subacute renal failure in 37% of the patients. The most prominent histological finding was diffuse interstitial edema of rapid onset, without signs of cellular or vascular rejection. In conclusion, we do not recommend IFN-alpha therapy for KT patients with chronic hepatitis C, until the mechanisms of the subsequent renal failure are better understood.
Nephron
1996
PMID:Acute renal failure in kidney transplant patients treated with interferon alpha 2b for chronic hepatitis C. 893 73
Contralateral uninephrectomy attenuates unilateral ischemic injury. The present work was performed to elucidate whether the beneficial effect of uninephrectomy was associated with the modification of
ischemia
-induced changes in plasma or renal renin activity. A 60-min left renal artery occlusion was conducted in right nephrectomized (Nx) and sham-nephrectomized (Sham-Nx) rats. The decline in inulin clearance 48 h after
ischemia
was significantly less in Nx rats than in Sham-Nx animals (0.50 +/- 0.10 vs. 0.052 +/- 0.029 ml/min/kidney, p < 0.05). Following
ischemia
, plasma renin activity (PRA) significantly increased in Sham-Nx (from 5.4 +/- 0.9 to 15.5 +/- 1.4 ng AI/ml/min, p < 0.01) but not in Nx (from 3.5 +/- 0.5 to 5.0 +/- 1.0 ng AI/ml/ min) animals. PRA and renal cortical renin content (2,200 +/- 225 vs. 1,257 +/- 187 ng AI/h/mg protein, p < 0.05) were significantly less in Nx rats than in Sham-Nx animals 48 h after renal ischemia. The decrease in body weight was greater in Nx rats than in Sham-Nx animals. Plasma atrial natriuretic peptide (ANP) (195 +/- 30 vs. 302 +/- 40 pg/ml, p < 0.05) and renal dopamine (DA) content (3.2 +/- 0.5 vs. 13.7 +/- 1.3 ng/g tissue, p < 0.01) were rather lower in the Nx group when compared with the Sham-Nx group. No significant difference was found in the intrarenal content of norepinephrine (NE) between two ischemic groups. These findings suggested that uninephrectomy prevents the
ischemia
-induced increase in renin activity. The prevention of the increase in renin activity in Nx rats is not be mediated through the modulation of
ischemia
-induced changes in sodium balance, plasma ANP level and/or intrarenal contents of NE and DA.
Nephron
1997
PMID:Uninephrectomy prevents the ischemia-induced increase in renin activity. 903 Dec 73
Long-term prognosis in kidney transplant recipients depends on multiple factors. To investigate whether mild proteinuria within the first 6 months following transplantation is a determinant of the long-term function and survival of kidney transplants, 357 patients transplanted between 1980 and 1990 were retrospectively examined over a period of 5 years. 25.5% of the patients developed an early proteinuria between 0.25 and 1.0 g/day over 6 or more months. This group was well matched concerning gender, age of recipient, underlying disease, time on hemodialysis, donor age, cold
ischemia
time and HLA mismatches with the group without proteinuria (n = 266). Five-year transplant survival in the group with proteinuria was 58.9% in contrast to 85.6% in recipients without proteinuria. Intermittent proteinuria did not worsen long-term prognosis. Proteinuria of 12 months or longer further reduced 5-year transplant survival to 42.6%. Over the whole observation period, serum creatinine in recipients with proteinuria was about 0.5 mg/dl higher as compared with patients without proteinuria. No correlation between proteinuria and gender, age of recipient, duration of hemodialysis, age of donor, cold
ischemia
time and mismatches could be detected. In conclusion, early proteinuria apparently is not due to established donor or recipient factors. However, there is a strong correlation of proteinuria with worse transplant function and survival.
Nephron
1997
PMID:Influence of proteinuria on long-term transplant survival in kidney transplant recipients. 904 35
This study was undertaken to test the hypothesis that
ischemia
prior to transplantation causes tubular damage without clinical evidence of graft dysfunction. The urinary excretion of fructose-1,6-bisphosphatase (EC 3.1.3.11, FBPase), a cytosolic enzyme located exclusively in the proximal tubules, and the lysosomal enzyme N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30) were measured daily between postoperative days 1 and 4 in 25 renal cadaveric graft recipients who enjoyed an entirely uncomplicated first postoperative month. During the first 4 posttransplant days urinary FBPase excretion was 0.9 +/- 0.5 U/g (0.1 +/- 0.06 U/mmol) urinary creatinine [+/-SD; range 0.2-2.1 U/g (0.02-0.24 U/mmol)]. Cold
ischemia
time was 20.6 +/- 8.4 h (median 22 h, range: 3-32 h). Multiple regression revealed a significant correlation between cold
ischemia
time and posttransplant urinary FBPase excretion (multiple R = 0.65, p < 0.001). There were no confounding effects of recipient's age and gender, number of previous transplants, cyclosporin A levels, warm
ischemia
time, anastomosis time, donor age and gender. Urinary FBPase excretion was significantly lower in grafts stored for a shorter time than the median cold
ischemia
time of 22 hours (0.69 +/- 0.42 U/g, n = 13) as compared to those stored for a longer period of time (1.13 +/- 0.56 U/g; n = 12; p = 0.035). These results indicate that graft injuries occur even in the absence of graft dysfunction and that the duration of cold
ischemia
itself correlates with a degree of tubular cell damage as defined by urinary FBPase excretion.
Nephron
1997
PMID:Graft ischemia correlates with urinary excretion of the proximal marker enzyme fructose-1,6-bisphosphatase in human kidney transplantation. 938 Feb 40
The effect of ginsenoside-Rd in ischemic-reperfused rats was examined. In control rats, blood and renal parameters and the activities of antioxidative enzymes in renal tissue deviated from the normal range, indicating dysfunction of the kidneys. In contrast, when ginsenoside-Rd was given orally for 30 consecutive days prior to
ischemia
and reperfusion, the activities of the antioxidation enzymes superoxide dismutase, catalase and glutathione peroxidase were higher, while malondialdehyde levels in serum and renal tissue were lower in the treated rats than in the controls. Decreased levels of urea nitrogen and creatinine in serum demonstrated a protective action against the renal dysfunction caused by
ischemia
and recirculation. On the other hand, it was demonstrated that ginsenoside-Rd affected cultured proximal tubule cells subjected to hypoxia-reoxygenation, probably by preventing oxygen free radicals from attacking the cell membranes.
Nephron
1998
PMID:A study of ginsenoside-Rd in a renal ischemia-reperfusion model. 949 38
The contributions of nitric oxide (NO) and renal blood flow (RBF) were examined in
ischemia
-reperfusion injury in the rat kidney. The function of both kidneys was assessed by glomerular filtration rate (GFR), and fractional excretion of sodium (FENa), calculated before, during unilateral renal artery clamping (45 min), and following reperfusion (90 min). RBF was measured in the same model by ultrasonic flowmetry. Intrarenal NO levels were modulated by administration of S-nitroso-N-acetylpenicillamine (SNAP), L-arginine, acetylcholine, and the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME). SNAP increased GFR from 0.20 +/- 0.04 ml/min in control ischemic kidney to 0.38 +/- 0.06 ml/min and reduced FENa from 19.3 +/- 3.4 to 9.5 +/- 1.8%. Similar results were observed when L-arginine was administered. Acetylcholine had no effect on GFR or FENa. RBF was fully restored within 60 min following reperfusion, with no change in the rate of recovery by L-arginine. L-NAME aggravated the
ischemia
-reperfusion injury, preventing full restoration of RBF, further reducing GFR and worsening FENa. In conclusion,
ischemia
-reperfusion injury ends in low intrarenal levels of NO. We propose that this low NO level results from damage to the endothelial receptor signal transduction process and is not due to impaired NO synthase activity or to changes in RBF.
Nephron
1998 Dec
PMID:Renal ischemia-reperfusion injury: contribution of nitric oxide and renal blood flow. 983 46
In order to estimate a regenerative response in the early phase after renal ischemia-reperfusion in rat, we examined the time course of the activation of epidermal growth factor receptor (EGFR) as a response of signal transduction pathway after 45 min
ischemia
in kidney. The activation of EGFR was observed 5-30 min after the start of reperfusion. Simultaneously, superoxide anion/hydrogen peroxide generated in the mitochondrial fraction was elevated during the same period. On the other hand, the level of EGF decreased in a time-dependent manner. These results suggested that superoxide anion/hydrogen peroxide generated during the
ischemia
-reperfusion other than EGF could act as an activator for the EGFR. In summary, the activation of EGFR is important as a regenerative response at an early stage after the start of reperfusion in ischemic kidney.
Nephron
1999 Feb
PMID:Activation of epidermal growth factor receptor in the early phase after renal ischemia-reperfusion in rat. 993 60
The pathogenesis of acute renal failure may involve, among other causes,
ischemia
, vascular congestion, arachidonic acid pathways, and reactive oxygen metabolites. The aim of this study is to evaluate the effects of pentoxifylline and vitamin E on the prevention of experimental acute renal failure induced by glycerol. Eighty-five Sprague-Dawley rats weighing 170-230 g were included in the study. The rats were randomly divided into four groups: group 1 was given 1 ml saline; group 2, glycerol; group 3, glycerol plus vitamin E, and group 4, glycerol plus pentoxifylline. Extent of histological renal tubular necrosis and regeneration in each animal were graded. Blood urea nitrogen, serum creatinine, and creatine kinase concentrations were measured. Mean blood urea nitrogen and serum creatinine concentrations and tubular injury scores were significantly lower in group 1 than in groups 2-4 (p < 0.001), but there were no significant differences among groups 2-4. We conclude that postinsult administration of vitamin E and pentoxifylline does not have a beneficial effect on prevention and severity of acute renal failure and that controlled, multicenter studies involving a large number of patients are needed to clarify this subject.
Nephron
2000 Mar
PMID:Effect of vitamin E and pentoxifylline on glycerol-induced acute renal failure. 1072 Aug 95
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