Development of Poland's Central Bone Marrow Donor Registry Affects Donor Searches for Patients With Hematological Diseases.

In the last 10 years, numbers of donors in the case of Polish potential unrelated hematopoietic stem cells (HSC) have increased dynamically, reaching 1,900,000 in 2020 (including donors presented in World Marrow Donor Association as PL6). On the world scale, the share of Polish donors in the global registry increased from 1% in 2010 to about 5% in 2020. The level and range of typing of potential donors has also been improving steadily toward the international "gold standard." At the end of 2020, 92% of Polish resources were at least HLA-A, B, C, DR, DQ high- or intermediate-resolution typed, mostly by way of genomic typing techniques, mostly by way of genomic typing techniques. The Central Bone Marrow Donor Registry (CBMDR) also stands out in terms of the young ages of potential donors. As of 2020, 27.2% of those registered were younger than 30 years of age, and 36.3% were aged between 30 and 40 years. Sixty percent of registered donors were female. The data in question were presented at the World Marrow Donor Association Search & Match Service, ensuring their visibility and accessibility to Polish and international search units and registries. In 2020, donors in Poland were the subject of almost 18,000 search requests from 40 countries, with 271 extended typing requests and more than 7600 confirmatory typing requests. The total number of donations from Polish donors also increased. In 2020, HSC of bone marrow, peripheral blood, or lymphocytes were collected from 1391 donors, as opposed to 94 donors in 2010. The growing number of donors available in the CBMDR means a better chance of a donor being found among Polish resources, without any need to resort to international registers. Although in 2010, just 24% of Polish recipients received HSC from Polish donors, by 2019 the figure was as high as 67%, and reached 63% in 2020. The CBMDR is an example of proper strategy on registry development being implemented in Poland.

Individual and regional factors of access to the renal transplant waiting list in france in a cohort of dialyzed patients.

Several studies have investigated geographical variations in access to renal transplant waiting lists, but none has assessed the impact on these variations of factors at both the patient and geographic levels. The objective of our study was to identify medical and non-medical factors at both these levels associated with these geographical variations in waiting-list placement in France. We included all incident patients aged 18-80 years in 11 French regions who started dialysis between January 1, 2006, and December 31, 2008. Both a multilevel Cox model with shared frailty and a competing risks model were used for the analyses. At the patient level, old age, comorbidities, diabetic nephropathy, non-autonomous first dialysis, and female gender were the major determinants of a lower probability of being waitlisted. At the regional level, the only factor associated with this probability was an increase in the number of patients on the waiting list from 2005 to 2009. This finding supports a slight but significant impact of a regional organ shortage on waitlisting practices. Our findings demonstrate that patients' age has a major impact on waitlisting practices, even for patients with no comorbidity or disability, whose survival would likely be improved by transplantation compared with dialysis.

The random phase approximation applied to ice.

Standard density functionals without van der Waals interactions yield an unsatisfactory description of ice phases, specifically, high density phases occurring under pressure are too unstable compared to the common low density phase Ih observed at ambient conditions. Although the description is improved by using functionals that include van der Waals interactions, the errors in relative volumes remain sizable. Here we assess the random phase approximation (RPA) for the correlation energy and compare our results to experimental data as well as diffusion Monte Carlo data for ice. The RPA yields a very balanced description for all considered phases, approaching the accuracy of diffusion Monte Carlo in relative energies and volumes. This opens a route towards a concise description of molecular water phases on surfaces and in cavities.

[ESRD in children and adolescents]. / Enfants et adolescents en IRCT.

This chapter provides indicators to describe the specificity of End Stage Renal Disease in children in France and to study these patients'outcome and the choices of treatment modalities. In 2011, the incidence and the prevalence of ESRD among patients under 20 years old remained stable at 8 and 53 pmp respectively. The first causes of ESDR remain uropathies and hypodysplasia followed by glomerulonephritis and genetic diseases. Considering the initial treatment, we found a high rate of hemodialysis and a low rate of peritoneal dialysis that is mainly used in younger children. In 2011, 31 preemptive transplantations were performed accounting for 27.7% of new patients. Finally, survival analysis confirm that younger children (under 4 years old) have the highest risk of death (88% survival rate at 2 years vs. 98% in patients over 4 years old) and that the treatment of choice remains the renal transplantation since it increases the expected remaining lifetime of 20 to 40 years depending on the considered age.

Disparities in policies, practices and rates of pediatric kidney transplantation in Europe.

We aimed to provide an overview of kidney allocation policies related to children and pediatric kidney transplantation (KTx) practices and rates in Europe, and to study factors associated with KTx rates. A survey was distributed among renal registry representatives in 38 European countries. Additional data were obtained from the ESPN/ERA-EDTA and ERA-EDTA registries. Thirty-two countries (84%) responded. The median incidence rate of pediatric KTx was 5.7 (range 0-13.5) per million children (pmc). A median proportion of 17% (interquartile range 2-29) of KTx was performed preemptively, while the median proportion of living donor KTx was 43% (interquartile range 10-52). The median percentage of children on renal replacement therapy (RRT) with a functioning graft was 62%. The level of pediatric prioritization was associated with a decreased waiting time for deceased donor KTx, an increased pediatric KTx rate, and a lower proportion of living donor KTx. The rates of pediatric KTx, distribution of donor source and time on waiting list vary considerably between European countries. The lack of harmonization in kidney allocation to children raises medical and ethical issues. Harmonization of pediatric allocation policies should be prioritized.

[Evolution of the access to the kidney transplantation in France of foreign patients and French patients living in overseas territories]. / Évolution de l'accès à la greffe rénale en France des patients étrangers ou résidant outre-mer.

In France, foreign patients, whether resident or not in France, can register on the national waiting list under administrative and financial conditions. We performed a retrospective analysis to evaluate the access to kidney transplantation on a cohort 2004-2008, using the national registry. Among the 14,732 patients registered during this period, 15.3% are of non-French nationality (3.4% other European, 5.9% North African, 3.9% sub-Saharan African, 2.9% other). Among the 84.6% of French nationality, 3.3% are living in French overseas territories. Compared to the 17.6-month median waiting time of the cohort, median waiting time differs significantly between groups, from 15.7 months for mainland French patients to 36 months for sub-Saharan African patients. Despite the regular development of the allocation rules, these disparities in access to transplantation are mainly, but not completely, explained by blood group or HLA matching difficulties. After adjustment for the other factors known to be significantly linked to a difficult access to transplantation, North and sub-Saharan African patients have the worst difficulties. Future research should consider nonmedical factors, such as socio-economic or socio-cultural factors, potentially relevant to avoid disparities in access to transplantation and should aim at developing specific interventions.

Stability of coagulation factors in thawed, solvent/detergent-treated plasma during storage at 4 degrees C for 6 days.

BACKGROUND AND OBJECTIVES: Transfusion of fresh-frozen plasma is still a pillar in emergency medicine for using to prevent dilutional coagulopathy or disseminated intravascular coagulation after severe blood loss, but thawing procedures can delay its availability. On the other hand, the wastage of plasma, once thawed and not transfused within a defined time-period, represents an inefficient handling of economic resources and is contradictory to blood donor intentions. In this study we investigated the stability of coagulation factor activities and plasma protein levels during 6 days of storage of thawed solvent/detergent (S/D)-treated plasma at +4 degrees C. Our results may form the basis for reconsideration of expiry times of thawed S/D-treated plasma. MATERIALS AND METHODS: Five units of S/D-treated plasma (Octaplas) were thawed and warmed to 20 degrees C, then recooled and stored at +4 degrees C for 6 days. The activities of coagulation factors II, V, VII, VIII, IX, X, XI and XII, fibrinogen, antithrombin (AT), protein C, protein S and von Willebrand factor antigen (vWF:Ag) were measured on days 0, 1, 2, 3 and 6. RESULTS: Except for protein S, the activities of all coagulation factors and inhibitors were at least 0.5 U/ml during storage at 4 degrees C for 6 days. The mean levels, during storage, of factors IX, X, XI and XII, vWF:Ag, fibrinogen and protein C were at least 94%, and of factors II, V and VIII, and AT at least 78%, of the levels immediately after thawing; the activity of factor VII decreased to 83% and of protein S to 43% of the baseline values. CONCLUSIONS: Thawed S/D-treated plasma stored at +4 degrees C for up to 6 days still contains sufficient coagulation activities and plasma proteins to be regarded as suitable for transfusion in the established indications.

Fibrin sealant produced by the CryoSeal FS System: product chemistry, material properties and possible preparation in the autologous preoperative setting.

BACKGROUND AND OBJECTIVES: The CryoSeal FS has been introduced as an automated device for the production of fibrin sealant from small volumes of plasma. We tested this device and compared the product with commercially available fibrin sealants and with the requirements of the European Pharmacopoeia. MATERIALS AND METHODS: The CP3 program and disposables required were used to manufacture fibrin sealant. The chemistry and mechanical properties of the product were investigated. RESULTS: The cryoprecipitate generated with CryoSeal contains concentrated fibrinogen and critical clotting factors. The efficiency of the production process is poor, but the production procedure itself is simple and not time-consuming. The volume of plasma required allows application in the preoperative autologous setting. CONCLUSIONS: The CryoSeal FS is an automated device for cryoprecipitation and production of thrombin. It can be implemented easily in the clinical routine, although, owing to product specifications, the efficacy of the CryoSeal fibrin sealant requires further clinical trials.

Laparoscopic retroperitoneal nephrectomy in high risk children.

PURPOSE: Nephrectomy may be indicated in children with end stage renal disease before transplantation. We studied the feasibility and results of nephrectomy performed via a retroperitoneal laparoscopic approach in these high risk children. MATERIALS AND METHODS: We performed 12 nephrectomies in 9 children with end stage renal disease and a mean age of 7 years (range 7 months to 13 years) through a 3 trocar retroperitoneal laparoscopic approach. Cases were classified as American Society of Anesthesiologists grade III and presented with end stage renal disease, hypertension, thrombocytopenia and/or the nephrotic syndrome. The renal artery and vein were ligated separately with endocorporeal knots and clips. Mean size of the kidney was 8 cm. (range 5 to 12). Bilateral nephrectomy was performed simultaneously in 2 patients 7 and 12 months old, respectively. Cardiorespiratory changes related to retroperitoneal gas insufflation were assessed prospectively. To compare laparoscopic versus open nephrectomy we retrospectively analyzed the data of 12 open nephrectomies performed in 9 children with similar nephrological indications. RESULTS: The procedure was feasible in all cases without conversion to open surgery, and no intraoperative incident occurred. Mean operative time of laparoscopic nephrectomy was 2 hours (range 1 hour 20 minutes to 3 hours 10 minutes). After retroperitoneal carbon dioxide insufflation systolic arterial pressure and end-tidal carbon dioxide were significantly increased without the need for specific measure to correct these modifications. Hemodialysis began 1 day postoperatively and feeding began 2 days postoperatively. Mean hospital stay was 5.2 days (range 3 to 7). The comparative study of the open nephrectomy group showed no significant difference in mean operating time (p = 0.07), and hospital stay was significantly shorter for the laparoscopic group (p <0.001). CONCLUSIONS: Retroperitoneal laparoscopic nephrectomy is safe and feasible for high risk children. The relatively long operating time is necessary for hemostasis in these children at risk for hemorrhagic complications.

Outcome of posterior urethral valves: to what extent is it improved by prenatal diagnosis?

PURPOSE: To assess the impact of prenatal diagnosis and evaluation on the outcome of posterior urethral valves we studied all cases of valves detected prenatally, including cases of pregnancy termination due to posterior urethral valves. MATERIALS AND METHODS: Between 1989 and 1996, 30 neonates with prenatally detected posterior urethral valves were treated at our hospital. The prenatal parameters analyzed were age of gestation at diagnosis, ultrasonographic appearance of renal parenchyma and amniotic fluid volume. Fetal urine was analyzed in 9 cases. We reviewed the outcome of 10 neonates treated for posterior urethral valves which were not diagnosed prenatally during the same period. RESULTS: Of the 30 neonatal survivors 6 (20%) had renal failure, including end stage renal disease in 2, after a mean followup of 4 years. Renal failure developed in 2 of 5 cases detected before 24 weeks of gestation, in 1 of 6 with oligohydramnios and in 2 of 5 with abnormal parenchymal renal ultrasound. Normal parenchymal ultrasound and amniotic volume could not predict for good outcome. Renal failure developed in 2 of 7 cases predicted by fetal urinalysis as good prognosis and in 1 of 2 cases predicted as poor prognosis. Pregnancy was terminated for posterior urethral valves in 5 cases based on prenatal criteria of severe renal impairment. Considering these cases as poor outcome, the rate of poor prognosis increased from 20 to 31%. Among the 10 neonates without a prenatal diagnosis of posterior urethral valves renal failure developed in 2 (20%), including end stage renal disease in 1. CONCLUSIONS: When negative parameters were absent and/or fetal urine predicted good outcome there were no cases of end stage renal disease in early infancy, which was a significant help in parent counseling. The predictive value of the currently available prenatal parameters needs to be updated with larger series specifically dealing with posterior urethral valves. According to the current data, the outcome of posterior urethral valves is not yet significantly improved by prenatal diagnosis.

Pharmacokinetics of the S(+) and R(-) enantiomers of vigabatrin during chronic dosing in a patient with renal failure.

AIMS: To study the pharmacokinetics of vigabatrin in a patient affected with tuberous sclerosis who developed major agitation and aggression, while receiving vigabatrin orally (1.5 g every 12 h) and in whom impaired renal function was diagnosed. METHODS: The patient received vigabatrin (0.5 g day(-1)). A pharmacokinetic study of the S(+) and R(-) enantiomers of vigabatrin was performed before and during dialysis. Plasma concentrations were measured at 0, 1, 2, 3, 4, 6, 12, 18 and 24 h by a specific GCMS assay. RESULTS: Before dialysis, the maximum and minimun plasma concentrations of vigabatrin at steady-state were lower for the S(+) than for the R(-) enantiomer, while the apparent oral clearance was higher for the S(+) than for the R(-) enantiomer (2.97 vs 0.48 l h(-1)). In addition, the haemodialysis clearance was similar for the two enantiomers (4.96 vs 5.15 l h(-1)). CONCLUSIONS: Vigabatrin is an irreversible inhibitor of GABA-transaminase, effective in the treatment of drug-resistant epilepsy and reported to be eliminated unchanged by renal excretion. Although vigabatrin is known to have stereoselective kinetics, the difference in plasma dry concentrations and pharmacokinetics of the S(+) and R(-) enantiomers that we observed during long term administration at high doses in a patient with impaired renal function, has not been reported before. The question remains of the potential toxicity of the high levels of the R(-) enantiomer.

Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP).

Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with homologies to endopeptidases, on the X-chromosome), are responsible for X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has raised important questions regarding PEX function at the molecular level. The aim of this study was to analyse 99 HYP families for PEX gene mutations, and to correlate predicted changes in the protein structure with Zn2+ metallopeptidase gene function. Primers flanking 22 characterised exons were used to amplify DNA by PCR, and SSCP was then used to screen for mutations. Deletions, insertions, nonsense mutations, stop codons and splice mutations occurred in 83% of families screened for in all 22 exons, and 51% of a separate set of families screened in 17 PEX gene exons. Missense mutations in four regions of the gene were informative regarding function, with one mutation in the Zn2+-binding site predicted to alter substrate enzyme interaction and catalysis. Computer analysis of the remaining mutations predicted changes in secondary structure, N-glycosylation, protein phosphorylation and catalytic site molecular structure. The wide range of mutations that align with regions required for protease activity in NEP suggests that PEX also functions as a protease, and may act by processing factor(s) involved in bone mineral metabolism.

[Vitamin A poisoning revealed by hypercalcemia in a child with kidney failure]. / Intoxication à la vitamine A révélée par une hypercalcémie chez un enfant insuffisant rénal.

BACKGROUND: Patients with chronic renal failure are at risk of vitamin A intoxication, a risk that must be evoked when unexplained hypercalcemia occurs. CASE REPORT: An 8 year-old boy with Alagille syndrome and chronic renal failure was admitted because of general deterioration, and bone pain. Severe hypercalcemia (3.9 mmol/L) was present. Serum phosphate, parathyroid hormone and 25 OH D3 levels were normal; 1-25 (OH)2 D3 levels were undetectable. Hypercalcemia was attributed to vitamin A intoxication, due to the administration of a mean daily dose of 12000 IU of vitamin A for at least 2 years. The diagnosis was confirmed by high plasma levels of retinol (1475 micrograms/L). Hypercalcemia only partially responded to treatment with bisphosphonates, calcitonin and dialysis with low calcium dialysate. Serum vitamin A levels remained elevated one month after vitamin A withdrawal. The boy died two months after admission from atrioventricular block. CONCLUSION: Vitamin A administration induces a high risk of intoxication in patients with chronic renal failure. Serum vitamin A concentrations are elevated in these patients, because of decreased renal metabolism of retinol, and vitamin A supplements must be avoided.

Pharmacokinetics of ganciclovir in renal transplant children.

Three cytomegalovirus (CMV)-seronegative children received renal transplants from CMV-seropositive donors and developed clinical symptoms of CMV infection between days 20 and 34 post transplantation. Ganciclovir (DHPG) was administered in a 1-h infusion, and the doses and dose intervals were adapted to the degree of renal insufficiency, according to the manufacturer's recommendations for adults. Individual pharmacokinetic parameters of DHPG were determined and were markedly altered. Plasma clearances were 0.4, 1.1 and 2.2 ml/min per kg and were related to individual creatinine clearances (20, 45 and 60 ml/min per 1.73 m2); the corresponding elimination half-lives were 23.7, 9.9 and 3.9 h. In two patients, the doses had to be further reduced in order to maintain plasma levels within the recommended values for peak and trough plasma concentrations. Therefore, monitoring of DHPG appears essential in adjusting dosage for optimal efficacy and minimal toxicity.

[Prognosis of prune belly syndrome]. / Pronostic du syndrome d'aplasie des muscles de la paroi abdominale.

The Prune Belly syndrome (PBS) is unfrequent. Fourteen cases have been followed in our unit during the last 20 years. Four infants (29%) died during the first months of life, because of neonatal sepsis (2 cases) or end-stage renal failure (2 cases). Among the other 10 cases, 6 (43%) had normal glomerular filtration rate at a mean age of 10 years 6 months (6 months to 15 years), 4 had chronic renal failure, including 3 cases who developed end-stage renal failure at 8, 8 years 8 months and 17 years respectively. Resection of an urethral obstruction was performed in 2 cases. This surgical indication remains widely accepted, while the current tendency is to limit ureteral surgery in PBS. Orchidopexy was performed in 4 children, 3 of them less than 6 years 6 months of age. Fertility of these early operated children remains to be established, as all adults reported in the literature remain sterile when orchidopexy was not performed or was performed after age 6.