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F Oppenheimer

Publications and source records attributed to F Oppenheimer.

At least 73 records · Page 4Linked to original sources
PubMed1999

Losartan decreases plasma levels of TGF-beta1 in transplant patients with chronic allograft nephropathy.

BACKGROUND: Chronic allograft nephropathy represents the principal cause of graft loss after the first year of transplantation. Transforming growth factor-beta1 (TGF-beta1) is a key factor in fibrogenesis and has been involved in the pathogenesis of chronic allograft nephropathy and other chronic nephropathies. Experimental studies have demonstrated that the angiotensin II receptor antagonist (losartan) could decrease the synthesis of TGF-beta1. The aim of this study was to determine the plasma levels of TGF-beta1 in transplant patients with chronic allograft nephropathy, and to evaluate the effect of losartan on TGF-beta1 plasma levels and other vasoactive peptides (angiotensin II, plasma renin activity, aldosterone, endothelin-1, and nitrites and nitrates). Angiotensin-converting enzyme genotypes were also determined in all patients. METHODS: Fourteen transplant patients with chronic allograft nephropathy were included. Treatment with losartan (50 mg) was introduced. Consecutive determinations of TGF-beta1 and other vasoactive peptides were performed during follow-up. RESULTS: Patients with chronic allograft nephropathy presented higher plasma levels of TGF-beta1 than the control groups. The treatment with losartan significantly decreased the plasma levels of TGF-beta1 (P < 0.05) and endothelin (P < 0.05) in all patients. The decrease of TGF-beta1 was statistically correlated with the blockade of the angiotensin II receptor (P < 0.05). No significant correlation could be demonstrated between angiotensin-converting enzyme genotypes and TGF-beta, endothelin-1, and nitrite-nitrate serum levels. CONCLUSIONS: This study demonstrates that losartan significantly decreases the plasma levels of TGF-beta1, the most important fibrogenetic factor. These results could play a decisive role in the treatment and prevention of chronic nephropathies, not only graft nephropathy, because the intrinsic pathogenetic mechanism is very similar in all forms, with a crucial roles for the renal renin-angiotensin system and TGF-beta1.

Adult↗
PubMed1999

[Compression of the sciatic nerve in uremic tumor calcinosis].

Tumoral calcinosis is an uncommon and benign condition characterized by the presence of slow-growing calcified periarticular soft tissue masses of varying size. They are usually asymptomatic and nerve compression is rare. We describe the case of a 54-year-old female patient on long-term hemodialysis for chronic renal failure presenting sciatica in the left lower limb secondary to an extensive uremic tumoral calcinosis that affected the hip and thigh. The pathogenesis of uremic tumoral calcinosis as well as the treatment and clinical outcome are analyzed. The uncommon nerve compression due to tumoral calcinosis are reviewed. In conclusion, uremic tumoral calcinosis is a not previously reported infrequent cause of sciatic nerve compression.

Calcinosis↗
PubMed1999

Uremic tumoral calcinosis in patients receiving longterm hemodialysis therapy.

OBJECTIVE: To analyze a series of uremic tumoral calcinosis (UTC) in patients receiving longterm dialysis therapy. METHODS: Twelve patients receiving longterm hemodialysis affected by tumoral calcinosis were analyzed. Clinical, radiological, and pathological features were evaluated and pathogenic factors were reviewed. RESULTS: The most common sites for UTC were the elbow, hip, hand, and wrist. The lesions were multiple (67%, n = 8), of large size, and symptomatic with joint mobility impairment (75%, n = 9) as well as nerve compression (33%, n = 4). High serum calcium and phosphate concentrations were detected in 50% (n = 6) and 100% of the patients, respectively. An increased calcium-phosphorus product (Ca x P) was observed in all patients, either due to overt secondary hyperparathyroidism (42%, n = 5), or secondary to iatrogenic hypercalcemia and/or severe hyperphosphoremia of multifactorial etiology (i.e., prolonged and excessive administration of calcitriol and calcium carbonate, insufficient dialysis and inadequate phosphorus chelating therapy, etc.) (58%, n = 7). Several treatment strategies were followed (surgical excision, parathyroidectomy, renal transplant) in combination with aggressive medical therapy to decrease Ca x P product, achieving complete remission in 83% of the patients. CONCLUSION: UTC lesions show clinical and pathogenic features that differ from those of idiopathic tumoral calcinosis. The most important pathogenic factor involved in UTC is an increase in Ca x P, not necessarily related to hyperparathyroidism. Combined treatment strategies allow complete remission in a high proportion of patients. A low Ca x P is necessary to prevent development of UTC.

Adult↗
PubMed1998

A case of renal artery stenosis after transplantation: can losartan be more accurate than captopril renography?

Hypertension is a common complication observed after renal transplantation. If the hypertension is of renovascular origin, transluminal angioplasty or surgery of the renal artery stenosis can lead help cure the hypertension. The blood pressure of a 31-year-old man who underwent renal transplantation 2 years earlier gradually increased. Arteriography showed stenosis (>80%) in the two branches of the renal artery. To help confirm the presence of renovascular hypertension, captopril renography was performed but showed no significant changes compared with baseline renography. Renography was performed again after losartan administration and showed impaired renal function. In this case, losartan renography was more useful than captopril in suggesting renovascular hypertension.

Adult↗
PubMed1997

Membranous glomerulonephritis associated with hepatitis C virus infection in renal transplant patients.

BACKGROUND: Hepatitis C virus (HCV) infection has been described in association with various types of glomerular diseases, usually type I membranoproliferative glomerulonephritis and rarely membranous glomerulonephritis (MGN). In this article, we describe the first series of MGN exhibited in renal transplant patients and associated with HCV infection. METHODS: From January 1980 to December 1994, 2045 kidney transplantations were performed in our renal transplant units. A retrospective analysis demonstrated an overall 20% prevalence of HCV virus-positive patients; 409 transplanted patients were HCV positive (ELISA and RIBA). RESULTS: Fifteen patients developed an allograft MGN (3.66%) 24 months after renal transplantation. MGN appeared in the form of significant proteinuria (>1.5 g/24 h) with stable renal function. In all cases, graft biopsy demonstrated a thickening of the capillary wall, subepithelial electron-dense deposits, and IgG and C3 diffuse granular deposits along the basal membrane. Ten cases were considered de novo, two cases were considered recurrent MGN, and three cases were considered undetermined because the primary renal disease was chronic glomerulonephritis. All patients showed negative antinuclear antibodies and cryoglobulins, normal complement, and negative rheumatoid factors. During follow-up (an average of 2 years), 12 patients developed a progressive worsening of renal function, with increased serum creatinine and persistent proteinuria; 8 of the 12 patients returned to dialysis. Of the remaining three cases, two patients showed partial remission of nephrotic syndrome after high doses of steroids, and one patient persisted with stable renal function and proteinuria (<2 g/24 h.). CONCLUSIONS: In summary, HCV is preferentially associated with MGN in renal transplant patients, rather than with membranoproliferative glomerulonephritis as in the normal adult population. MGN associated with HCV infection has a similar clinical picture and outcome to posttransplant idiopathic de novo MGN, with persistent massive proteinuria and progressive deterioration of renal function.

Adult↗
PubMed1996

Study of kidney rejection following simultaneous kidney-pancreas transplantation.

Simultaneous kidney-pancreas (SKP) transplantation is associated with increased risk of kidney rejection (KR) due to an unknown mechanism. The aim of this study is to analyze the characteristics of KR in 44 SKP transplantations under quadruple immunosuppressive therapy and to evaluate the response to treatment and its effect on renal allograft survival and renal function. The mean follow-up was 25 +/- 14 months. Seventy-seven percent of the patients (34 of 44) presented an acute renal allograft rejection. Sixty-six percent (29 of 44) had one rejection episode and 11% (5 of 4) 2 episodes. KR was early (85% in the first month after transplantation), intense (3.7-fold increase in creatinine) and had great clinical features. Twenty-eight percent of the patients had an early relapse during the first month after treatment. KR did not affect the survival of the renal allograft in the short-term (1 and 2 years). Overall, 62% were corticosensitive (CS) and the remaining 38% were corticoresistant (CR). The group with an isolated rejection without relapse was CS in 69% of the cases, achieved complete remission in 73% and renal function was not affected at 1 and 2 years [115 +/- 26 mumol/l (1.3 +/- 0.3 mg/dl) and 150 +/- 53 mumol/l (1.7 +/- 0.6 mg/dl)] in comparison with the group without rejection [97 +/- 18 mumol/l (1.1 +/- 0.2 mg/dl) and 115 +/- 35 mumol/l (1.3 +/- 0.4 mg/dl); p = NS]. On the other hand, the group with an early relapse of the first rejection and the group with two rejections were principally CR (62 and 60%, respectively), had partial remission with treatment (50 and 60%) and had worse renal function at 1 and 2 years [212 +/- 71 mumol/l (2.4 +/- 0.8 mg/dl) and 221 +/- 53 mumol/l (2.5 +/- 0.6 mg/dl)] than in the group with isolated KR (p < 0.05 and p < 0.001). In conclusion, despite intense immunosuppressive treatment, the frequency of rejection of a renal allograft in SKP is high. The response to treatment is satisfactory and does not affect the survival of the allograft in the short-term. However, multiple episodes or early relapse of rejection are associated with higher creatinine levels.

Adult↗