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P Niaudet

Publications and source records attributed to P Niaudet.

At least 19 recordsLinked to original sources
PubMed2006

Rituximab therapy for childhood-onset systemic lupus erythematosus.

OBJECTIVE: To describe the safety and efficacy of rituximab in the treatment of childhood-onset systemic lupus erythematosus (SLE). STUDY DESIGN: We conducted a French multicenter retrospective study of childhood-onset SLE treated with rituximab. RESULTS: Eleven girls with severe SLE, including 8 girls with class IV or V lupus nephritis, 2 girls with severe autoimmune cytopenia, and 1 girl with antiprothrombin antibody with severe hemorrhage, were treated with rituximab. The mean age at onset of rituximab treatment was 13.9 years. Patients received 2 to 12 intravenous infusions of rituximab (350-450 mg/m2/infusion), with corticosteroids. Six patients also received different standard immunosuppressive agents, including Cyclophosphamide (2 patients). Remission was achieved in 6 of 8 patients with lupus nephritis and in the 2 patients with autoimmune cytopenia. Steroid therapy was tapered in 5 patients who responded to treatment, and low-dose prednisone treatment was maintained in 1 patient. The mean follow-up period was 13.2 months (range, 6-26 months), and remission lasted in all who patients who responded to treatment, except 1 patient who was successfully retreated with a second course of rituximab. Anti-double-stranded DNA antibody levels decreased in 6 of 11 patients, and anticardiolipin antibody levels decreased in 3 of 4 patients. Severe adverse events developed in 5 patients. Effective depletion of peripheral blood B cells was observed in 7 of 8 patients who were examined, and this paralleled the remission. CONCLUSION: Rituximab may be an effective co-therapy; however, further investigations are required because severe adverse events occurred in 45% of the patients in this study.

Adolescent↗
PubMed2005

Initial presentation of childhood-onset systemic lupus erythematosus: a French multicenter study.

OBJECTIVE: To describe the clinical and laboratory manifestations of childhood-onset systemic lupus erythematosus (SLE) at presentation. STUDY DESIGN: This retrospective French multicenter study involved 155 patients in whom SLE developed before the age of 16 years. Mean patient age at onset was 11.5 +/- 2.5 years (range, 1.5-16 years). The female to male ratio was 4.5. RESULTS: The most common initial manifestations were hematologic (72%), cutaneous (70%), musculoskeletal (64%), renal (50%), and fever (58%). Thirty-two percent of children had atypical symptoms, mainly including abdominal involvement in 26 patients, which lead to negative laparotomy results for presumed appendicitis. Severe renal, neurologic, hematologic, abdominal, cardiac, pulmonary, thrombotic, and/or cutaneous manifestations occurred within the first month after the diagnosis in 40% of patients. The mean erythrocyte sedimentation rate was 72 +/- 29 mm/h, and the mean C-reactive protein value 22 +/- 21 mg/L. Antinuclear antibodies an, anti-double stranded DNA antibodies, and low C3 or C4 level were retrieved in 97%, 93%, and 78 % of patients, respectively. CONCLUSION: Initial manifestations of childhood-onset SLE are diverse and often severe. The diagnosis of SLE should be promptly considered in any febrile adolescent with unexplained organ involvement, especially when associated with an increased erythrocyte sedimentation rate.

Child↗
PubMed2004

[Disseminated lupus erythematosus in children: guidelines about investigations during the initial evaluation and follow-up].

Childhood-onset systemic lupus erythematosus (SLE) is often severe and has a serious long-term morbidity. Pediatric guidelines about its management do not exist. The French study group of childhood-onset SLE proposes recommendations about the investigation which are needed at diagnosis and during follow-up of SLE, in order to adjust the treatment according to the severity of the disease and to avoid unnecessary investigations.

Aftercare↗
PubMed2001

A pharmacokinetic study of Neoral in childhood steroid-dependent nephrotic syndrome.

Seven children with steroid-dependent nephrotic syndrome who were on stable remission under Sandimmun therapy were switched to Neoral at the same dosage. During the 4-month follow-up period, two patients relapsed, due to poor compliance in one of them. Serum creatinine remained stable in all patients. Pharmacokinetic profiles were performed at day 0 while on Sandimmun and 4 weeks after conversion to Neoral. Following conversion to Neoral, the peak concentration occurred earlier (2+/-1.4 h vs 3.9+/-2.4 h), and the maximum concentration (677+/-386 ng/ml vs 488+/-265 ng/ml) and the area under the curve (3,082+/-1,536 ng/ml/h vs 2,201+/889 ng/ml/h) were higher. We conclude that Neoral results in an increased bioavailability of cyclosporine (CsA) as compared to Sandimmun in patients with steroid-dependent nephrotic syndrome in remission.

Adolescent↗
PubMed2001

Long term results of liver-kidney transplantation in children with primary hyperoxaluria.

From 1990 to 2000, we performed eight liver-kidney transplants in eight children, aged 1-16 years, with end-stage renal failure (ESRF) due to primary hyperoxaluria (PH1). The duration of dialysis before transplantation ranged from 2 to 42 months (mean 14 months) and was <1 year in four patients. Only the first patient underwent postoperative hemodialysis; in the other five, we chose to induce maximal diuresis from the first hours with intravenous and intragastric hyperhydration (> or =3 l/m2 per day). High water intake with nocturnal tube hydration was maintained for 6 months to 5 years, as long as oxaluria exceeded 0.5 mmol/day. A quadruple sequential immunosuppressive regimen was used. Two patients died during liver graft surgery. The other six patients are alive and well, with a mean follow-up of 7.4 years (range 5-11 years). Patient and graft survival is 75% at 5 years. At latest follow-up, liver tests were normal in all six patients; creatinine clearance ranged from 55 to 95 ml/min per 1.73 m2 (mean=74). Oxaluria was lower than 0.4 mmol/day in all patients (mean=0.22). The six patients underwent 15 renal biopsies, 1-11 years after transplantation. Chronic transplant nephropathy was present in four patients and mild cyclosporin nephrotoxicity in another. No oxalate crystals were seen and repeat ultrasonography has been consistently normal in all patients. The three patients with bone oxalosis showed progressive complete healing of bone lesions. All six children or adolescents now live a normal life. From this series, we conclude that early combined liver-kidney transplantation is the treatment of choice for children with ESRF due to primary hyperoxaluria.

Adolescent↗
PubMed2001

One-year routine renal transplant biopsies in children.

In our institution, systematic renal graft biopsies are performed 1 year after transplantation before deciding to switch to alternate-day steroid therapy, which has been shown to be beneficial for statural growth. We analyzed the results of systematic graft biopsies in 145 children with a creatinine clearance > or =45 ml/min per 1.73 m2. Biopsies were classified according to Banff diagnostic categories. Normal parenchyma was observed in 19 cases (13%), non-specific lesions in 42 cases (29%), chronic allograft nephropathy grade 1-3 in 68 cases (49%), and acute rejection in 8 cases (5%). Clinicopathological correlations indicated that patients with chronic allograft nephropathy had received kidneys from older donors, with longer cold ischemia time and with a higher incidence of delayed graft function. There was a strong correlation between the donor age and the presence of vascular lesions. There was also a good correlation between the severity of histological lesions and the occurrence of acute rejection episodes during the 1st year after transplantation. Renal function remained stable for up to 10 years in patients with normal parenchyma or non-specific lesions, while serum creatinine levels increased after the 2nd year in patients with chronic allograft nephropathy.

Acute Disease↗
PubMed2001

High serum levels of a non-(1-84) parathyroid hormone (PTH) fragment in pediatric haemodialysis patients.

The measurement of serum intact parathyroid hormone (PTH) is routinely made in haemodialysed (HD) patients to diagnose and monitor secondary hyperparathyroidism. We measured pre- and post-dialysis serum ionized calcium (Ca2+) and PTH in 12 HD children (7 boys) aged 13.8+/-3.6 years. A group of 27 normal short-statured children served as controls. Serum PTH was assessed by a new assay (CAP) recognizing only the (1-84) molecule and an older one (Allegro) recognizing both the 1-84 and a non-(1-84) PTH equally. The concentrations obtained with the CAP assay were lower than those obtained with the Allegro assay both in controls and in HD patients. They were still lower in HD patients when expressed as multiples of the median of the control group. The Allegro/CAP ratio, was highly variable from one subject to another and was lower (P<0.0001) in controls (1.46+/-0.26) than in HD patients, both before (3.06+/-1.60) and after dialysis (2.94+/-0.65). During dialysis, Ca2+ increased significantly (P<0.0001) and PTH decreased significantly (P<0.0001) with both the CAP and the Allegro assays, but was more often normal or low with the CAP than with the Allegro assay. Although the two assays correlate well, they may provide different clinical information in some HD children which could lead to different therapeutic decisions.

Adolescent↗
PubMed2001

[Analgesia with oxygen-nitrous oxide mixture during percutaneous renal biopsy in children].

UNLABELLED: The efficacy of an inhaled equimolar mixture of nitrous oxide and oxygen (Entonox/MEOPA) to prevent procedural pain during renal percutaneous biopsies in children was assessed. PATIENTS AND METHODS: One hundred and seven children who underwent 113 renal biopsies during a 17-month period were included in a prospective uncontrolled pediatric study. Efficacy was evaluated using patients' answers to a questionnaire and nurses' observations. RESULTS: Pain was absent in 86.5% of the cases. Mild adverse events were noted in one-third of the procedures, and were always reversible within a few minutes when the inhalation stopped. Acceptability was good. The use of this gas is easy and safe provided a few precautions are observed. CONCLUSION: Inhaled equimolar mixture of nitrous oxide and oxygen prevents procedural pain during renal percutaneous biopsies.

Administration, Inhalation↗
PubMed2001

A mutant mitochondrial respiratory chain assembly protein causes complex III deficiency in patients with tubulopathy, encephalopathy and liver failure.

Complex III (CIII; ubiquinol cytochrome c reductase of the mitochondrial respiratory chain) catalyzes electron transfer from succinate and nicotinamide adenine dinucleotide-linked dehydrogenases to cytochrome c. CIII is made up of 11 subunits, of which all but one (cytochrome b) are encoded by nuclear DNA. CIII deficiencies are rare and manifest heterogeneous clinical presentations. Although pathogenic mutations in the gene encoding mitochondrial cytochrome b have been described, mutations in the nuclear-DNA-encoded subunits have not been reported. Involvement of various genes has been indicated in assembly of yeast CIII (refs. 8-11). So far only one such gene, BCS1L, has been identified in human. BCS1L represents, therefore, an obvious candidate gene in CIII deficiency. Here, we report BCS1L mutations in six patients, from four unrelated families and presenting neonatal proximal tubulopathy, hepatic involvement and encephalopathy. Complementation study in yeast confirmed the deleterious effect of these mutations. Mutation of BCS1L would seem to be a frequent cause of CIII deficiency, as one-third of our patients have BCS1L mutations.

ATPases Associated with Diverse Cellular Activitie↗
PubMed2001

PAX2 mutations in oligomeganephronia.

BACKGROUND: Oligomeganephronia (OMN) is a rare congenital and usually sporadic anomaly. It is characterized by bilateral renal hypoplasia, with a reduced number of enlarged nephrons. The mechanisms involved in this deficient nephrogenesis are unknown. The paired box transcription factor PAX2 plays a fundamental role in renal development. Heterozygous Pax2 mutants in mice are characterized by renal hypoplasia and retinal defects, and in humans, PAX2 mutations have been described in the renal-coloboma syndrome. METHODS: To assess whether OMN could be related to PAX2, we searched for PAX2 mutations in nine patients presenting with sporadic and apparently isolated OMN. RESULTS: Heterozygous PAX2 mutations were found in three patients. A limited optic nerve coloboma was secondarily detected in two cases and a very mild optic disk dysplasia in one patient. None of these patients had visual impairment. CONCLUSIONS: Ocular anomaly and PAX2 mutations should be sought in all patients with OMN.

Adolescent↗
PubMed2001

Urological complications after renal transplantation using ureteroureteral anastomosis in children.

PURPOSE: Ureterovesical reimplantation is most often performed for renal transplantation in children. We reviewed our experience to evaluate the safety and efficacy of ureteroureteral reimplantation in pediatric renal transplantation. MATERIALS AND METHODS: We retrospectively evaluated the charts of 92 boys and 72 girls who underwent a total of 166 ureteroureteral anastomoses for renal transplantation from January 1990 to December 1999. Spatulated end-to-end anastomosis was performed between recipient and graft ureters without stenting and with a bladder catheter for at least 10 days. RESULTS: Mean patient age at transplantation was 11.2 years (range 1 to 21.5). There were 22 living related donor and 144 cadaveric grafts. Urological anomalies and nephropathy were the cause of end stage renal disease in 146 and 20 patients, respectively. Urological complications were noted in 14 of the 166 transplantations (8.4%) in 10 boys and 4 girls, including 12 initial and 2 repeat grafts from 2 living related and 12 cadaveric donors. Five of these patients had undergone previous urological surgery. The 2 children (1.2%) with acute ureteral obstruction underwent repeat intervention after stent failure. Anastomotic leakage in 7 cases (4.2%) was treated conservatively in 1 and with a Double-J stent (Medical Engineering Corp., New York, New York) only required in 3. Reoperation was required in 3 cases. One patient (0.6%) with late ureteral stenosis underwent repeat anastomosis, 1 (0.6%) required reimplantation for recurrent pyelonephritis due to vesicoureteral reflux in the graft, 1 (0.6%) with a valve bladder required bladder augmentation and ureteral reimplantation, and 1 (0.6%) with lymphocele and 1 (0.6%) with lithiasis were successfully treated conservatively. Complications were associated with acute rejection in 6 cases. Mean followup without graft loss in patients who presented with versus without complications was 58.3 months (range 1 to 112) versus 75 (range 1 to 118). In the former patients with a mean age of 16 years 9 months versus those without urological complications mean serum creatinine was 116 and 108 mol./l., respectively. Two grafts were lost in patients with urological complications, including 1 who died of pulmonary embolism and 1 with refractory chronic rejection. Seven patients were lost to followup after 54 months (range 12 to 113) of adequate graft function. CONCLUSIONS: Ureteroureteral anastomosis is a safe and effective technique for pediatric renal transplantation with a low complication rate, which may be due to better vascularization of the shorter ureteral end of the graft. Our results should encourage the use of this technique in pediatric renal transplantation. Efforts to preserve the recipient ureters should be made at nephrectomy.

Adolescent↗
PubMed2000

[Rheumatoid purpura].

Schönlein-Henoch purpura is a clinical syndrome characterized by the association of skin, joint and gastrointestinal symptoms consisting respectively in purpura, arthralgia and abdominal pain. The incidence of renal symptoms ranges from 33 to 50%. The long term prognosis is related to the renal disease which is characterized by a glomerular involvement, with hematuria and sometimes proteinuria. In more severe cases, a nephrotic syndrome is present with a decrease in renal function. A renal biopsy is performed when proteinuria is in excess of 1 g/day. It shows a mesangial proliferation and in more severe cases extracapillary proliferation while mesangial IgA deposits are seen by immunofluorescence. Severe forms require a treatment with corticosteroids, started with methylprednisolone pulses. Treatment should be started early in the course of the disease before glomerular crescents become fibrous.

Humans↗