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M Hourmant

Publications and source records attributed to M Hourmant.

At least 55 records · Page 3Linked to original sources

Evidence that early acute renal failure may be mediated by CD3- CD16+ cells in a kidney graft recipient with large granular lymphocyte proliferation.

We report here on a patient with a large granular lymphocyte proliferative disease who received a third kidney allograft. This patient presented a lymphocytosis (culminating at approximately 30,000/mm3) with a large proportion (approximately 70%) of CD3- WT31- CD2+ CD16+ lymphocytes. Five days after a kidney graft and during prophylactic treatment by Ortho pan OKT3, he presented an acute graft failure with an apparent interruption of graft blood flow as assessed by the Tc99 scan pattern and an arteriogram. The biopsy showed an abnormal accumulation of intravascular CD3- CD16+ cells bound to endothelial cells with thrombilike patterns in small and middle-sized arteries, whereas CD3+ mononucleated cells infiltrate was restricted to interstitium as observed in his previous graft, performed before the appearance of the lymphoproliferative disorder. The syndrome resolved spontaneously. The role of OKT3-mediated release of cytokines able to upregulate endothelial cell adhesion molecules in triggering this phenomenon is discussed.

Acute Kidney Injury↗

[Early failure in kidney transplantation].

Parameters of early failure in kidney transplantation have been analyzed from 507 transplantations with transplant loss in the first month, selected among the 7541 cadaveric kidney transplantations performed in France between 1985 and 1989. These failures represent 6.7 percent of the population transplanted over this period of time, 68.6 percent of the failures that occurred in the first 3 months post-grafting, and 47 percent of the total number of the first year failures. Comparing patients with and without transplant failure in the first month, sex of the donor and the recipient, ABO group of the donor and the recipient, origin of the kidney, cold ischemia time, HLA compatibility, dialysis duration, number of previous transplantations, showed no influence on the occurrence of early failure. Three parameters appeared to be significant risk factors: donor's age less than 5 years, P = 0.00001; recipient's age less than 5 years, P = 0.05; pregraft immunization, P = 0.002. Furthermore, multifactorial analysis showed that the absence of HLA compatibilities between donor and recipient in hyperimmunized patients also has a significant influence on early graft loss. However, comparison of these same parameters in patients with transplant failure within the first month and between 2 and 12 months post-grafting revealed that the influence of these 4 significant parameters is longstanding and that none of them is specific of the precocity of graft loss.

Adolescent↗

Effect of the number of pregraft blood transfusions in kidney graft recipients treated with bioreagents and cyclosporin A.

The impact of a systematic, nondonor-specific, pregraft blood transfusion (BT) protocol was evaluated retrospectively in 446 consecutive, first renal transplant recipients with regard to graft survival rate, rejection, and incidence of infectious episodes. Cyclosporin A was the maintenance immunosuppressive treatment in all patients after a 2-week course of antithymocyte globulin or anti-IL-2 monoclonal antibody. Recipients were assigned to three groups according to the number of pregraft BT (one or two, three or four, or more than four). When nonimmunological failures were excluded from the study, patients receiving three or four BT had statistically better graft survival (P less than 0.02) and a lower incidence of rejection episodes (P less than 0.05) than those in the other groups. There were no significant differences between the three groups in the distribution of HLA mismatching (A, B and DR), time interval between the last BT and transplantation, DR6 recipient phenotype, or nonimmunological failures. Our results show that the number of pregraft BT is an important factor in transplantation.

ABO Blood-Group System↗

Effect of anti-LFA1 (CD11a) monoclonal antibodies in acute rejection in human kidney transplantation.

A murine IgG1 monoclonal antibody, 25-3 (Immunotech, France), directed against the alpha chain (CD11a) of the human LFA1 molecule was used in the treatment of 7 histologically documented first acute rejection in first kidney transplantations under cyclosporine. Four patients (group I) received 20 mg/day for 2 days and 10 mg/day for 8 days of 25-3 MoAb. One developed Quincke's edema after the first injection of 25-3 and was immediately withdrawn from the study. In 2 patients, whose serum creatinine continued to increase, 25-3 MoAb was replaced by steroids, followed by ALG after 3 and 4 days of treatment, respectively. In the last case, rejection was reversed by 25-3 MoAb alone. As the clinical response of rejection to 25-3 was poor, another group of 3 patients (group II) was treated with 25-3 at a dose of 40 mg/day for 2 days, 20 mg/day for 2 days, and 10 mg/day for 6 days, but 25-3 was still unsuccessful in reversing acute rejection, and rescue treatment was initiated between days 5 and 8 in all cases. MoAb tolerance was excellent in 3 patients. With the exception of the one case of Quincke's edema, only minor side effects were noted in the last 3 recipients. 25-3 MoAb serum trough levels peaked between 1.5-3.5 micrograms/ml at day 3 in group I and between 2-9 micrograms/L at day 2 in group II. Surprisingly, only one patient, in group I, exhibited a borderline IgG immune response against 25-3. These findings suggest that the 25-3 anti-CD11a MoAb is ineffective in controlling the course of acute rejection in kidney transplantation. However as already reported for another anti-LFA1 or with an anti-CD4 MoAb in mouse, 25-3 would be the first example in humans of a MoAb that does not elicit a strong immune response against its own determinants. This property might have important applications if 25-3 can prevent rejection in a prophylactic protocol or block the immune response against other MoAbs.

Adult↗

Recurrent nephrotic syndrome following renal transplantation in patients with focal glomerulosclerosis. A one-center study of plasma exchange effects.

Forty seven renal allografts performed over a period of 12 years in 43 recipients with chronic renal failure due to biopsy-proved focal glomerulosclerosis (FGS, 5.34% from 888 cadaveric renal transplantations) were reviewed. Recurrence of the disease was suspected in 14 grafts (29.8%) on the basis of immediate proteinuria, but recurrence of FGS lesions was demonstrated in only 7 patients. The remaining 7 patients had minimal-change nephropathy or mesangial hyperplasia. The duration of renal disease before transplantation was a clear predictive risk factor of FGS recurrence, and mesangial hyperplasia in the native kidneys was associated with 50% risk of FGS recurrence. Some reports have suggested that plasma exchange may be beneficial in the treatment of FGS recurrence. Our experience, in 9 patients, indicates that plasma exchange initiated early in the course of recurrent proteinuria leads to transient but significant disappearance (2 cases) or decrease (5 cases) of proteinuria, with a return to pre-plasma exchange levels within 2 weeks after the end of treatment. In 2 cases, there was no beneficial effect on proteinuria. Plasma exchange efficacy was correlated with proteinuria levels relative to disease severity. Although plasma exchange does not seem to improve the outcome of FGS recurrence, it demonstrates the possible presence of circulating factor(s) and argues for the characterization of humoral mediator(s).

Complement C1q↗

Vesicoureteral reflux in the renal transplantation candidate.

The incidence and severity of urinary tract infection episodes were evaluated in two groups of renal transplantation patients. Group 1 consisted of 11 patients transplanted following successful surgical correction of a noninfected vesicoureteral reflux in native kidneys, and group 2 of 28 patients transplanted with a noninfected vesicoureteral reflux. An increased incidence of acute urinary tract infection episodes was noted in group 2 as compared to group 1 (42.8 vs. 18%), with a mean of 2.6 +/- 1.4 episodes per patient in group 2 and 0.5 +/- 0.32 in group 1. Asymptomatic bacteriuria was not statistically different in the two groups (36.4 vs. 25%). In group 2, the incidence of urinary tract infection episodes increased in patients presenting high-grade (3 and 4) reflux in native kidneys. Despite the relatively low number of patients involved, our observations indicate that high-grade vesicoureteral reflux in native kidneys must be operated before transplantation, even when there is no history of urinary tract infections and urine cultures are sterile.

Acute Disease↗

Randomized controlled trial of a monoclonal antibody against the interleukin-2 receptor (33B3.1) as compared with rabbit antithymocyte globulin for prophylaxis against rejection of renal allografts.

Interleukin-2 is a major growth factor for activated T lymphocytes, and antibodies reacting with the Tac-chain component of the interleukin-2 receptor can prevent allograft rejection in animals. Because Tac chains are expressed only on a small fraction of activated lymphocytes, monoclonal antibodies against the interleukin-2 receptor may offer a more specific means of immunosuppression than polyclonal antilymphocyte globulin in prophylaxis against graft rejection. Therefore, we compared the immunosuppressive effect of 33B3.1, a rat monoclonal antibody against the human Tac chain, with the effect of a rabbit polyclonal antithymocyte globulin in a randomized study of 100 recipients of first renal transplants. Injections of 33B3.1 (10 mg per day) were tolerated well, whereas major side effects in 15 of 47 patients (32 percent) receiving antithymocyte globulin required discontinuation of treatment before day 14. The incidence of rejection episodes was not statistically different in the two groups at days 14, 30, 60, and 90 after transplantation. Patient and graft survival was also equal in the two groups at one year (96 and 85 percent, respectively, in both groups), and graft function was similar. The total number of infectious episodes within the first three months was lower in the 33B3.1 group than in the antithymocyte group (47 vs. 72). The drop in peripheral-blood lymphocyte concentrations was significantly larger in the patients treated with antithymocyte globulin. The level of circulating Tac-chain-bearing lymphocytes remained below 1 percent during 33B3.1 treatment, as compared with 4 to 5 percent during antithymocyte-globulin treatment (P not significant). We conclude that 33B3.1 is as effective as antithymocyte globulin in the prevention of renal-transplant rejection, and its use results in fewer infections and side effects.

Adolescent↗