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L De Pauw

Publications and source records attributed to L De Pauw.

At least 37 records · Page 2Linked to original sources

[Primary hyperoxaluria].

Primary hyperoxaluria is a rare hereditary disease. Two types have been identified. Type 1 is due to the deficiency of the liver-specific peroxisomal enzyme alanine:glyoxylate aminotransferase/serine: pyruvate amino-transferase whereas, in type 2, the deficiency concerns the glyoxylate reductase/D-glycerate dehydrogenase, a cytosolic enzyme present in the leucocytes and hepatocytes. In the elapsed decade, important progress in molecular biology led to the introduction of new strategies in the diagnosis and treatment of type 1 primary hyperoxaluria. However, the greater rarity of type 2 has so far prevented similar development. The present review recalls the normal metabolism of oxalic acid, details its deviations and their clinical consequences, and describes the methods of diagnosis and treatment to be presently recommended in primary hyperoxaluria.

Biopsy↗

Prevention of OKT3 nephrotoxicity after kidney transplantation.

In our experience the use of OKT3 as prophylaxis in renal transplantation has been associated with an increased incidence of both delayed graft function and thromboses of graft vessels. OKT3 nephrotoxicity might have been favored by restriction of perioperative fluid infusion to prevent pulmonary edema and by the use of very high dose (30 mg/kg) of methylprednisolone (mPDS) before the first OKT3 injection to reduce the release of cytokines. This led us to modify our perioperative management in three ways: (1) hydration status was optimalized; (2) the calcium-channel blocker diltiazem, considered beneficial for recovery of graft function, was administered on the day of transplantation; and (3) the dose of mPDS given before the first OKT3 injection was fixed at 8 mg/kg. Comparison of two consecutive series of patients (group 1, control patients, N = 172; group 2, managed as described above, N = 173) showed that: (1) the incidence of delayed graft function fell from 52% in group 1 to 22% in group 2 (P < 0.0001): (2) the incidence of pulmonary edema was not significantly increased in group 2 (3.5% vs. 1.7% in group 1, P = 0.5); and (3) the frequency of intragraft thrombosis fell from 7.6% in group 1 to 1.2% in group 2 (P = 0.0034). Multivariate analysis showed that the volemia/diltiazem program and avoidance of high mPDS dose were the most important factors responsible for the reduced occurrence of delayed graft function and graft vessels thrombosis, respectively. We conclude that a combined strategy of appropriate dosage of steroids before the first OKT3 injection, administration of a calcium-channel blocker and optimalization of volemia is safe and efficiently prevents against OKT3 nephrotoxic effects.

Adult↗

Influence of donor-recipient HLA-DR mismatches and OKT3 prophylaxis on cadaver kidney graft survival.

Previous studies from our center have shown that donor-recipient HLA-DR mismatches (MM), characterized by the presence of the DR antigen in the donor but not in the recipient or vice versa, are associated with differential effects on graft survival (GS): some of them are beneficial (BEN) with results similar to those of HLA-DR identical or compatible pairs (85% 18 months GS) and some are detrimental (DET) (64% 18 months GS), whereas the other MM, neither BEN nor DET (neutral [NEU]) yield intermediate results (78% 18 months GS). The aim of the present study was to update the results at a longer follow-up time and to assess whether they are influenced or not by prophylactic administration of anti-CD3 mAb (OKT3). The analysis of 234 transplantations performed from 1980 to 1994 with only 1 HLA-DR MM confirmed the BEN effects of HLA-DR5 in either the donor or the recipient and the DET effects of HLA-DR1 or -DR2 in the donor and of HLA-DR2 or -DRW6 in the recipient. These effects were independent of those exerted by other, HLA-DR not related, prognostic factors. The transplants with 1 HLA-DR MM were then compared with those with zero HLA-DR MM (n = 378) and 4 groups were formed according to 2 levels of HLA-DR MM (zero or BEN MM vs. NEU or DET MM) and immunosuppression (with vs. without OKT3 prophylaxis). GS at 5 years was 63% in the group with either zero or BEN MM as compared with 41% in the group with either NEU or DET MM in the absence of OKT3 prophylaxis (P < 0.02); in comparison, with OKT3 prophylaxis, GS at 5 years was 73% in the group with either zero or BEN MM as compared with 58% in the group with either NEU or DET MM (P = 0.07). We conclude that the differential effects of HLA-DR MM on GS are still observed under OKT3 prophylaxis, that the effects of HLA-DR and immunosuppression on graft outcome are additive, and that OKT3 induction therapy is superior to therapy without OKT3. These observations could have important implications for the allocation policy and management of renal transplants.

Adult↗

Combined liver-kidney transplantation in primary hyperoxaluria type 1. Bone histopathology and oxalate body content.

In three patients with end-stage renal failure due to primary hyperoxaluria type 1, successful combined liver-kidney transplantation enabled us to assess the insoluble oxalate pool, which was compared with the histopathological changes observed in iliac crest biopsy specimens. Good correlation was observed between the histopathological grade of bone oxalosis and the estimated oxalate content of the body. In the end-stage of oxalate bone disease, hyperparathyroidism does not play a significant role in bone resorption, which appears to be the consequence of the granulomatous reaction induced by oxalate deposition. Combined liver-kidney transplantation should be performed long before this stage. Early hepatorenal grafting in uremia secondary to primary hyperoxaluria type 1 would avoid the deleterious clinical consequences of systemic oxalosis and shorten the duration of postransplant hyperoxaluria, which may compromise the course of kidney graft.

Adolescent↗

Hypercalcaemia complicating systemic oxalosis in primary hyperoxaluria type 1.

Persistent hypercalcaemia was observed in two patients with oxalate osteopathy complicating primary hyperoxaluria type 1; four other cases have been reported in the literature. In none of the six patients could hypercalcaemia be ascribed to hyper-parathyroidism secondary to renal failure. It occurred in the absence of aluminum intoxication, and was associated with normal calcitriol. Hypercalcaemia responded to mithramycin in one patient, and to corticosteroid administration in three; corticosteroid withdrawal was followed by recurrence of hypercalcaemia in the three cases. It is suggested that hypercalcaemia results from the osteoclast-stimulating activity of macrophages constituting the granulomata which invade the bone marrow in response to oxalate deposition. Whatever its pathogenesis, a trial of corticosteroid appears warranted for treating hypercalcaemia complicating oxalosis.

Adrenal Cortex Hormones↗

[Primary hyperoxaluria].

Primary hyperoxalurias are inborn errors of metabolism with recessive autosomal transmission. Type 1 is due to the deficiency of the hepatic-specific peroxisomal enzyme alanine: glyoxylate aminotransferase, and type 2 to that of the glyoxylate reductase/D-glycerate dehydrogenase, present in the cytosol of hepatocytes and leucocytes. Type 3 is due to increased intestinal absorption of oxalate of unknown pathophysiology. In the 3 types, increased oxalate load may lead to systemic oxalosis when glomerular filtration rate decreases below 30 ml/min/1.73 m2, calcium oxalate saturation occurring in plasma when oxalate level approximates 50 mumol/l. High fluid intake and long-term co-administration of pyridoxine and orthophosphate could perhaps efficiently prevent renal failure in a majority of patients. However, combined liver-kidney transplantation presently constitutes the most adequate therapy of end-stage renal failure in type 1 and perhaps in type 2 hyperoxaluria.

Child↗

OKT3 serum levels as a guide for prophylactic therapy: a pilot study in kidney transplant recipients.

The use of OKT3 as prophylaxis in renal transplantation results in a reduced incidence of graft rejection and appears to have beneficial effects on long-term kidney graft survival. However, we and others have observed that patients still experience rejection during the period of OKT3 prophylaxis given at the regular 5 mg/day dose. Many of these patients had no circulating CD3+ cells at the time of rejection, but their OKT3 serum levels were distinctly low (< 500 ng/ml). This led us to adjust OKT3 doses (5 or 10 mg) daily, according to the patients' OKT3 levels, in order to maintain an OKT3 concentration of around 1000 ng/ml. In addition, patients were randomized to receive either 5 mg (group 1, n = 15) or 10 ng (group 2, n = 14) OKT3 as the initial three doses. Concomitant immunosuppression consisted of azathioprine and steroids, with the introduction of cyclosporin A on day 11. Patient survival was 100% after 3 months of follow-up. The intensity of OKT3 first-dose reactions was similar in both groups. Intragraft thrombosis, initially observed in a previous group of patients who received a fixed 10 mg/day OKT3 prophylaxis, occurred in three patients in group 1 and resulted in two graft losses. The cumulative OKT3 dose was similar in both groups (mean +/- SEM 98 +/- 2 mg in group 1 vs 102 +/- 3 mg in group 2) and higher than the 70 mg usually administered. Group 2 patients had higher OKT3 serum levels during the first 4 days of therapy. No correlation could be found between patient weight and cumulative OKT3 dose (r = 0.29).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Tuberculosis presenting as acute hepatitis in a renal transplant recipient.

We observed a kidney transplant recipient in whom acute hepatitis was the initial manifestation of tuberculosis, preceding radiological lung involvement by several weeks. The diagnosis was suspected and treatment initiated based on the finding of a granulomatous hepatitis on liver biopsy. Mycobacterial tuberculosis was grown and identified first in liver samples and only later in sputum and bone marrow. This case illustrates the protean manifestations of tuberculosis in immunosuppressed patients.

Acute Disease↗

High-dose glucocorticosteroids increase the procoagulant effects of OKT3.

The use of OKT3 as prophylaxis in renal transplantation carries an increased risk of intragraft thrombosis, which is related to the systemic activation of the coagulation system that consistently occurs after the first dose of OKT3. As only a few patients develop thrombosis after OKT3 therapy, we searched for possible additional risk factor by comparing the demographic and clinical parameters of the 13 patients who developed thrombosis in our institution to those of 218 patients who did not. Multivariate analysis showed a relationship between the dose of methylprednisolone (mPDS) given before the first OKT3 injection and the risk of thrombosis: 6 out of 42 patients (14%) who received high (30 mg/kg) mPDS experienced a thrombotic event, as compared to 7 out of the 189 patients (3.7%) who received < or = 8 mg/kg of mPDS (P < 0.01). This led us to study the effects of mPDS on the procoagulant activity induced by OKT3 on peripheral blood mononuclear cells (PBMC) in vitro. The procoagulant activity of unstimulated PBMC (mean +/- SEM: 0.6 +/- 0.1 mU/ml) reached 3.0 +/- 0.7 mU/ml after OKT3 stimulation (P = 0.0062) and further increased to 7.4 +/- 2.0 mU/ml when PBMC were first preincubated overnight with mPDS before OKT3 stimulation (P = 0.018 as compared to OKT3 alone). This process involved the tissue factor/factor VII pathway, as shown by increased membrane expression of tissue factor on monocytes as well as by a marked reduction of the induced procoagulant activity when the clotting assay was performed with factor VII-deficient plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Combined pancreatic and kidney transplantation: en bloc retrieval and transplantation--a new surgical technique.

We designed and performed on two patients a new surgical procedure of en bloc kidney and pancreatic transplantation. The liver, pancreas and kidneys were removed en bloc in the donor. On the bench, the liver and the left kidney were separated from the bloc, leaving the pancreas and the right kidney for combined kidney and pancreatic transplantation. The portal vein was divided near to the emergence of the splenic vein. The coeliac axis was taken with an aortic patch. The left renal vein was cut at its entrance to the inferior vena cava (IVC) and the left renal artery was taken with an aortic patch. Reconstruction of the pancreatic vessels was performed with a double anastomosis: the portal vein was anastomosed to the hole in the IVC resulting from the section of the left renal vein and the splenic artery was anastomosed to the hole in the aorta resulting from the section of the left renal artery. The proximal ends of the aorta and IVC were closed with running sutures. In the recipient, the iliac vessels on the right side were dissected. Anastomosis of the distal part of the aorta and the IVC was performed with the right iliac vessels. Duodenocystostomy and reimplantation of the ureter were done according to the usual techniques. This new surgical technique allowed an easy vascular reconstruction of the pancreatic vessels. In the recipient, only one side was used for renal and pancreatic transplantation. Moreover, the length of the transplant procedure was significantly reduced.

Anastomosis, Surgical↗