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E David-Neto

Publications and source records attributed to E David-Neto.

At least 19 recordsLinked to original sources
PubMed2005

Improvement of adynamic bone disease after renal transplantation.

Low bone remodeling and relatively low serum parathyroid hormone (PTH) levels characterize adynamic bone disease (ABD). The impact of renal transplantation (RT) on the course of ABD is unknown. We studied prospectively 13 patients with biopsy-proven ABD after RT. Bone histomorphometry and bone mineral density (BMD) measurements were performed in the 1st and 12th months after RT. Serum PTH, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and osteocalcin were measured regularly throughout the study. Serum PTH levels were slightly elevated at transplantation, normalized at the end of the third month and remained stable thereafter. Bone biopsies performed in the first month after RT revealed low bone turnover in all patients, with positive bone aluminum staining in 5. In the 12th month, second biopsies were performed on 12 patients. Bone histomorphometric dynamic parameters improved in 9 and were completely normalized in 6, whereas no bone mineralization was detected in 3 of these 12 patients. At 12 months post-RT, no bone aluminum was detected in any patient. We also found a decrease in lumbar BMD and an increase in femoral BMD. Patients suffering from ABD, even those with a reduction in PTH levels, may present partial or complete recovery of bone turnover after successful renal transplantation. However, it is not possible to positively identify the mechanisms responsible for the improvement. Identifying these mechanisms should lead to a better understanding of the physiopathology of ABD and to the development of more effective treatments.

Absorptiometry, Photon↗
PubMed2004

Induction versus noninduction therapy in kidney transplantation: considering different PRA levels and different induction therapies.

To evaluate the rate of acute cellular rejection (ACR) and long-term results in different levels of anti-HLA sensitization, using noninduction or different induction therapies, 763 patients who underwent transplantation from January 1995 to December 2001 were evaluated: 213 patients received induction therapy, 71 received Thymoglobulin (Thymo), 66 Simulect, and 44 OKT3. Follow-up time was at least 1 year for all groups. The Simulect group included older recipients and the OKT3 group had more female patients. Simulect and OKT3 groups had more black patients; Thymo and OKT3 groups had more retransplantations. PRA was low in the noninduction group (mean, 7%) and about the same in the Simulect and Thymo groups (mean, 30%). OKT3 was the most sensitized group (mean = 59%). Dialysis during the first posttransplantation week was more frequent among the induction groups (43% vs 65%; P <.005). Fewer patients experienced rejection episodes in the Thymo group (20% vs 50%; P =.02). Patients were classified according to their level of sensitization, and the Thymo group showed the lower rejection rates in all levels (mean, 20%; P =.001). When analyzing PRA >50%, the Thymo group showed lower rejection rates (12% vs 50%; P =.02). At this level of sensitization, there was no significant difference on graft loss and death with a functioning graft. There was a trend to more cytomegalovirus (CMV) disease in the Thymo group (33% vs 23%; P =.08). Two PTLD were diagnosed, both in the noninduction group. Renal function was better in the Thymo group (1.3 mg/dL). In conclusion, Thymo showed lower ACR rates in all PRA groups. No significant differences in CMV infection, tumors, and patient survival were observed.

Adult↗
PubMed2004

Identifying cyclosporine blood levels associated with the prevention of renal transplant rejection: a single-center, randomized prospective study.

Multiple-drug therapy may allow reduced individual drug doses with fewer side effects. Blood levels of cyclosporine (CsA) necessary to avoid rejection may vary with different drug combinations. Fifty-eight kidney transplant patients were randomized into two groups: 25 subjects were assigned to the 4-hour area under the curve (AUC(0-4)) Cohort-the "high arm" (4500 to 5500 ng . h/mL)--1 and 33 to the AUC(0-4) "low arm" (2400 to 3400 ng . h/mL). After CsA introduction, AUC(0-4) was drawn on days 4, 7, 14, 21, 28, 42, 56, 70, 84, 90. We compared the proportion of rejection versus rejection-free patients, according to the CsA exposure. Logistic regression analysis showed that an AUC(0-4) of > or =4000 ng . h/mL or a 2-hour cyclosporine level (C(2)) of > or =1450 ng/mL predicted a rejection-free course among patients not receiving induction therapy. When either basiliximab or thymoglobulin was administered, a C(2) and AUC(0-4) of 1043 +/- 151 ng/mL or 3146 +/- 262 ng . h/mL, respectively, were associated with a rejection-free course. Our findings confirm the need for different CsA levels to prevent rejection according to induction therapy. Induction with either basiliximab or thymoglobulin allows reduced CsA levels during the first 3 months after renal transplantation.

Adult↗
PubMed2001

Introduction of mycophenolate mofetil and cyclosporin reduction in children with chronic transplant nephropathy.

Chronic transplant nephropathy (CTN) is the most important cause of kidney graft dysfunction. Studies in adult populations have reported a beneficial effect of non-nephrotoxic mycophenolate mofetil (MMF) on graft function in this setting. However, few studies were reported in children in this setting. We therefore reviewed the charts/medical records of renal transplanted patients < 18 yr of age at a single center who had switched from azathioprine to MMF as a result of progressive loss in graft function, for which vascular, infectious, and urological causes were excluded. Serum creatinine (SCr) and calculated creatinine clearance were compared prior to and after MMF introduction. Thirteen patients (nine male/four female), followed-up for 59.3 +/- 35.4 months after transplantation, were analyzed. Age at MMF introduction was 14.2 +/- 3.6 yr. In 11 patients a previous biopsy had shown features of CTN and four patients also presented signs of chronic cyclosporin A (CsA) nephrotoxicity. MMF was started at a dose of 1211 +/- 351 mg/day, and the CsA dose was decreased from 6.69 +/- 3.15 mg/kg/day 6 months before MMF to 4.8 +/- 2.3 mg/kg/day at the time of MMF introduction. CsA was withdrawn in four patients. The median (25-75%) SCr value increased from 1.60 mg/dL (range 1.3 to 1.87 mg/dL) 6 months before MMF to 2.2 mg/dL (range 1.87-2.32 mg/dL) when MMF was introduced. Six months after introduction of MMF, the SCr level had decreased to 1.5 mg/dL (range 1.2-1.8 mg/dL) and remained stable until the last follow-up (17.5 +/- 9.2 months after MMF was started). A similar pattern occured with calculated SCr clearance. There were no acute rejections after changes in immunosuppression. The safety of MMF was also analyzed and in only one patient was the drug stopped as a result of intractable diarrhea. These findings suggest that MMF is sufficiently powerful to allow a decrease/withdrawal of CsA without the burden of acute rejection in a pediatric population with CTN.

Creatinine↗
PubMed1999

The impact of azathioprine on chronic viral hepatitis in renal transplantation: a long-term, single-center, prospective study on azathioprine withdrawal.

BACKGROUND: In transplanted patients, viral hepatitis progresses to chronic liver disease and patient's death after many years of transplantation. Also, it is well known that azathioprine (AZA) is harmful to the liver of these patients. However, it is unclear whether a low dose of AZA still represents a threat to the viral liver disease. METHODS: A total of 79 patients with hepatitis C, B, or both, transplanted between 1973 and 1990, were grouped according to whether they had AZA either withdrawn from the immunosuppressive regimen [group (G) I, n=45] or a dosage reduction only (group II, n=34). The decision to remove or to keep AZA was restricted to the patient's doctor. Patients records were reviewed by April 1997. RESULTS: After an equal time of follow-up, after the AZA changing (64+/-26 vs. 58+/-29 months), patients in GI showed a significant decrease in the serum liver parameters when compared to baseline [alanine aminotransferase (ALT): P=0.001; gamma-glutamyl transferase (gamma-GT): P=0.001 and total bilirubin: P=0.002], whereas in GII only ALT decreased (P=0.04) although gamma-GT and total bilirubin did not. Compared to baseline, serum creatinine (SCr) increased only in GI (P=0.001) but, at last follow-up, did not differ from GII. The intention-to-perform liver biopsies was equal in GI and GII (16 vs. 14) but the hystological findings of severe chronic liver disease (either chronic active hepatitis or cirrhosis) were more frequent in GII (P=0.004). Death with a functioning graft was much more frequent in GII than in GI (P=0.001). Infection and cirrhosis were more common as a cause of death in GII than in GI. CONCLUSIONS: The use AZA is harmful to renal transplantation patients with both chronic hepatitis C and B and, therefore, should be avoided. AZA withdrawal, but not dose adjustments, diminishes the serum liver enzymes and the progression rate of the chronic viral liver disease as well as the rate of death secondary to infection and cirrhosis.

Adult↗
PubMed1998

Contribution of the expression of ICAM-1, HLA-DR and IL-2R to the diagnosis of acute rejection in renal allograft aspirative cytology.

Acute rejection is associated with a poor long-term prognosis for renal allografts. Sequential fine-needle aspiration cytology (FNAC) has been used to monitor rejection. However, FNAC diagnoses rejection only when the infiltrating cells are already damaging the graft and, in some borderline cases with a low increment of inflammatory cells in the graft, FNAC lacks the specificity to diagnose rejection. In these cases, the number of inflammatory cells within the graft can decline, stabilize or increase with time. In this study, we sought to determine whether the analysis of the expression of ICAM-I, HLA-DR and IL-2R along with borderline FNAC results increases the specificity to diagnose rejection. Of 117 FNAC samples taken from 24 patients after renal transplantation, 85 (72%) were considered suitable for cytological analysis. Of these patients, 9 (37%) did not suffer an acute cellular rejection (ACR) episode and 15 (63%) had at least one ACR episode. ICAM-1 and IL-2R were studied using an immune-peroxidase technique. The ICAM-1 results are expressed as the percentage of tubular cells in the aspirate stained with this marker and the IL-2R results are expressed as the absolute number of positively stained lymphocytes in the whole cytopreparation. With a total corrected increment (TCI) of > 3 there was a sharp increase in the specificity index for rejection that reached almost 100% at a TCI of > or = 4. Sensitivity for rejection at this level was only 20%. Between a TCI of 2.5 and 2.9 the sensitivity increased to 75%, with specificity for rejection around 75%. There was an upregulation of ICAM-1 and IL-2R when FNAC diagnosed rejection but with a large overlap of the results when compared either to normal graft or acute tubular neurosis. The mean TCI during the week preceding the rejection episode was 2.5 and the TCI reached a mean value of > or = 3 only during rejection. The peak ICAM-1 and IL-2R expression occurred during the week preceding the clinically evident rejection episode. The expression of ICAM-1 by > or = 70% of the tubular cells increased the specificity for rejection of a TCI of > or = 2.5 to 100%. In the same way, the specificity for rejection increased up to 90% when eight to ten IL-2R-positive lymphocytes were seen along with a TCI of > or = 2.5. There was no further increase in specificity after that. A specificity index of 100% for rejection could be obtained for moderate levels of both ICAM-1 (70% or more tubular cells) and IL-2R (eight or more lymphocytes). ICAM-1 expression in 70% or more tubular cells and/or IL-2R expression in eight or more lymphocytes was found in 58% of the FNAC aspirates with a TCI between 2.5 and 2.9. In conclusion, the expression of IL-2R in lymphoid cells and ICAM-1 in tubular cells was upregulated during rejection episodes and the upregulation preceded both the clinical and the routine FNAC diagnosis of rejection by 1 week. The ddition of these markers to the FNAC increased substantially the specificity of the FNAC to diagnose rejection.

Acute Disease↗
PubMed1998

Post-transplant neutrophilic interstitial nephritis--an important cause of graft dysfunction.

Post-transplant neutrophilic interstitial nephritis (NIN) is characterized by an interstitial infiltrate consisting of polymorphonuclear cells that leads frequently to acute graft dysfunction. In 220 graft biopsies performed because of renal dysfunction over 2 years in our unit, 11 (5%) diagnoses of NIN were made. Only two patients had chronic pyelonephritis as original disease. Four patients had urological problems before transplantation. After transplantation, five patients had urinary tract infection, one had urethral stenosis, two had vesicourethral reflux and one patient had a perinephritic abscess. Seven patients had fever (63%). Only in six patients did urine culture lead to microorganism isolation. After 6 months, only two patients had a serum creatinine level < 1.4 mg/dl, five patients had abnormal function, three had lost their grafts, and one patient had died with sepsis. We conclude that 5% of the biopsies performed in our center disclosed NIN, an entity that causes graft dysfunction and progresses frequently to chronic renal failure. In some cases, no infectious etiology could be detected.

Female↗
PubMed1998

Role of the peripheral renin profile in predicting blood pressure control after bilateral nephrectomy in renal-transplanted patients.

BACKGROUND: The unregulated renin release by native kidneys is one of the factors responsible for the high incidence of hypertension after renal transplantation but, even after three decades of transplantation, there is still a lack of a method to identify it as the major cause of hypertension. METHODS: We investigated whether or not peripheral renin activity, before and 90 min after 25 mg of captopril, can play this role. One hundred and five consecutive patients with SCr less than 2 mg/dl were studied 18 +/- 8 months after renal transplantation. Forty-seven of them were considered hypertensive and 58 normotensive. All hypertensive patients were submitted to the captopril test to analyse the peripheral renin activity profile. RESULTS: In the hypertensive group, 17 patients (36%) were considered Renin-pos and 30 (64%) Renin-neg. All Renin-pos (stimulated renin = 19.1 +/- 6.4 ng/ml/h) patients were submitted to bilateral nephrectomy (bNx) and re-evaluated 6 months later. All of them normalized renin activity (4.4 +/- 3.0 ng/ml/h, P = 0.0001) and 10 of 17 (60%) became normotensive and off drugs. The remaining seven (40%) decreased the number of hypotensive drugs from 2.2 +/- 0.5 to 0.5 +/- 0.7/pt/day. There was a correlation between b-Renin and dBP (r = 0.47, P < 0.05) which was lost after bNx. An 'in situ' renal-cell carcinoma was found in two cases. Serum creatinine did not change. CONCLUSIONS: This study shows that the unregulated renin-angiotensin system from the native kidneys plays a major role in the maintenance of hypertension in some patients with normal graft function and that peripheral renin activity can identify those who will benefit from bilateral nephrectomy.

Adult↗
PubMed1993

Reversal of aluminum-related bone disease after renal transplantation.

We evaluated the course of severe aluminum-related bone disease (ARBD) after the first year of a successful renal transplantation (RTx) in 11 adult patients. Bone pain and muscle weakness, presented in all patients previously to RTx, subsided, and all were able to walk, even the ones who were confined to wheelchairs. Bone necrosis developed in 6 patients, but none required surgical repair. Serum alkaline phosphatase activity increased 2.5 times the upper normal level, up to the 5th month and then declined to normal levels up the 12th month (p < 0.05). The inverse profile was observed in both serum calcium and phosphorus levels. In bone biopsies, there was a significant decrease in all of the following histomorphometric static parameters: osteoid volume, thickness and surface and also in aluminum surface. Also, there was a significant increase in all the dynamic parameters of mineralization: mineral apposition rate, mineralization surface, bone formation rate and adjusted apposition rate. In conclusion, ARBD remarkably improves after 1 year of successful RTx.

Adult↗
PubMed1992

CSA/AZA, in the absence of prednisone, improves linear growth in renal transplanted children.

We compared the results of 44 renal transplants in children, of whom 24 were treated with CSA/AZA and 20 with prednisone in combination with AZA and/or CSA. There were no differences in age distribution or mean ages at transplant between the two treatment groups. The CSA/AZA group had a longer follow-up (29 +/- 33 vs 17 +/- 18 months). At the last follow-up, five children in the CSA/AZA and none in the prednisone group had lost their grafts. Serum creatinine increased in both groups from 0.7 +/- 0.1 mg/dl and 0.9 +/- 0.1 mg/dl at the end of the first month to 1.1 +/- 0.2 mg/dl in the 36th month (CSA/AZA group) (P < 0.0001) and to 1.5 +/- 0.6 mg/dl in the 18th month (prednisone group) (P < 0.05), respectively. Total cholesterol level was 189 +/- 52 mg/dl and 178 +/- 60 mg/dl and LDL level was 117 +/- 48 mg/dl and 115 +/- 51 mg/dl for the prednisone and CSA/AZA groups, respectively. HDL was greater in the CSA/AZA group (50 +/- 10 vs 41 +/- 10 mg/dl) (P < 0.03), and VLDL was greater in the prednisone group (31 +/- 13 vs 22 +/- 8 mg/dl) (P < 0.05). Serum triglyceride was greater in the prednisone group (174 +/- 93 vs 112 +/- 50 mg/dl) (P < 0.03). The standard deviation score for height of the children in the prednisone group did not change (-2.4 +/- 1.4 vs -2.1 +/- 1.4 SDS), whereas the SDS height score for the CSA/AZA children increased from -3.1 +/- 1.7 to -2.6 +/- 1.5, -1.9 +/- 1.4 and -1.7 +/- 1.4, at 12, 24 and 36 months, respectively (P < 0.001). CSA/AZA is a good immunosuppressive regime for the first renal transplant in children, but only 75% tolerated AZA/CSA without same damage to their grafts.

Azathioprine↗