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51.
52.
The severe side effects of long-term corticosteroid or cyclosporin A (CsA) therapy complicate the treatment of children with frequently relapsing steroid-sensitive nephrotic syndrome (FR-SSNS). We conducted a randomized, multicenter, open-label, crossover study comparing the efficacy and safety of a 1-year treatment with mycophenolate mofetil (MMF; target plasma mycophenolic acid trough level of 1.5–2.5 µg/ml) or CsA (target trough level of 80–100 ng/ml) in 60 pediatric patients with FR-SSNS. We assessed the frequency of relapse as the primary endpoint and evaluated pharmacokinetic profiles (area under the curve [AUC]) after 3 and 6 months of treatment. More relapses per patient per year occurred with MMF than with CsA during the first year (P=0.03), but not during the second year (P=0.14). No relapses occurred in 85% of patients during CsA therapy and in 64% of patients during MMF therapy (P=0.06). However, the time without relapse was significantly longer with CsA than with MMF during the first year (P<0.05), but not during the second year (P=0.36). In post hoc analysis, patients with low mycophenolic acid exposure (AUC <50 µg⋅h/ml) experienced 1.4 relapses per year compared with 0.27 relapses per year in those with high exposure (AUC>50 µg⋅h/ml; P<0.05). There were no significant differences between groups with respect to BP, growth, lipid levels, or adverse events. However, cystatin clearance, estimated GFR, and hemoglobin levels increased significantly with MMF compared with CsA. These results indicate that MMF is inferior to CsA in preventing relapses in pediatric patients with FR-SSNS, but may be a less nephrotoxic treatment option.Idiopathic nephrotic syndrome, the most common form of childhood nephrotic syndrome, is most often associated with renal biopsy findings of minimal glomerular and tubulointerstitial changes (minimal change disease). Most patients respond to therapy with corticosteroids,1 but about 70% experience a relapsing course.2 Approximately 30% develop frequently relapsing steroid-sensitive nephrotic syndrome (FR-SSNS), defined as ≥4 relapses per year.3Although corticosteroids are the mainstay of therapy in pediatric patients with minimal change disease, their repeated use in FR-SSNS results in severe side effects, and other therapeutic options are needed to prevent steroid toxicity.4 A 2- to 3-month course of cyclophosphamide or chlorambucil has been shown to produce a longer remission period in many patients5; however, these drugs may have serious side effects and their long-term efficacy is limited.6,7 Levamisole has been shown to reduce the risk of relapse in several small studies, but information is limited regarding long-term efficacy and adverse effects, and the drug is currently not available in most countries. Treatment with cyclosporin A (CsA) is highly effective in maintaining remission in patients with FR-SSNS allowing withdrawal of corticosteroids, but most patients relapse after withdrawal of CsA.8 Importantly, prolonged CsA therapy is accompanied by time- and dose-dependent nephrotoxicity.9Mycophenolate mofetil (MMF), the prodrug of mycophenolic acid (MPA), is a non-nephrotoxic immunosuppressive drug with inhibitory effects on T and B lymphocytes, cell-surface markers, and cytokine gene expression10 and has proven efficacy and tolerability in renal allograft recipients. Several small studies with limited statistical power have shown that MMF has steroid-sparing effects and reduces relapse rates in patients with FR-SSNS, albeit with varying efficacy.1118We studied efficacy and safety of MMF in patients with FR-SSNS in comparison with CsA in a prospective randomized multicenter open-label crossover trial.  相似文献   
53.
Little information exists regarding the efficacy, modifiers, and outcomes of anemia management in children with CKD or ESRD. We assessed practices, effectors, and outcomes of anemia management in 1394 pediatric patients undergoing peritoneal dialysis (PD) who were prospectively followed in 30 countries. We noted that 25% of patients had hemoglobin levels below target (<10 g/dl or <9.5 g/dl in children older or younger than 2 years, respectively), with significant regional variation; levels were highest in North America and Europe and lowest in Asia and Turkey. Low hemoglobin levels were associated with low urine output, low serum albumin, high parathyroid hormone, high ferritin, and the use of bioincompatible PD fluid. Erythropoiesis-stimulating agents (ESAs) were prescribed to 92% of patients, and neither the type of ESA nor the dosing interval appeared to affect efficacy. The weekly ESA dose inversely correlated with age when scaled to weight but did not correlate with age when normalized to body surface area. ESA sensitivity was positively associated with residual diuresis and serum albumin and inversely associated with serum parathyroid hormone and ferritin. The prevalence of hypertension and left ventricular hypertrophy increased with the degree of anemia. Patient survival was positively associated with achieved hemoglobin and serum albumin and was inversely associated with ESA dose. In conclusion, control of anemia in children receiving long-term PD varies by region. ESA requirements are independent of age when dose is scaled to body surface area, and ESA resistance is associated with inflammation, fluid retention, and hyperparathyroidism. Anemia and high ESA dose requirements independently predict mortality.Almost three decades after the advent of recombinant erythropoietin, the management of renal anemia has become a recent focus of attention and changing paradigms. Whereas correction of hemoglobin (Hb) levels to near-normal has previously been recommended on the basis of association studies linking more severe anemia to morbidity and mortality with dialysis,13 interventional clinical trials consistently demonstrate that near-normalization of Hb increases the risk of vascular events and mortality in adults receiving maintenance hemodialysis and in those with CKD who are not undergoing dialysis.46 This has prompted ongoing reevaluation and revisions of treatment targets in patients exposed to erythropoiesis-stimulating agents (ESAs).7The appropriateness of applying treatment recommendations established in adult hemodialysis populations at high cardiovascular risk and adults with CKD to children undergoing dialysis is questionable because cardiovascular events are far less common in children with CKD. Furthermore, two thirds of children requiring dialysis initially opt for peritoneal dialysis (PD), and there are no systematic studies in the adult PD population to inform the optimal Hb target range in these patients. The risk profile of patients receiving PD may differ from that of the hemodialysis setting because of the absence of dialysis-induced intermittent hemoconcentration and lack of contact activation of the complement and coagulation systems.Further aspects to consider in pediatric anemia management are the greater physical activity of children and the need for optimal cognitive functioning at school.8,9 The significant physiologic variation of the normal Hb range with age10 and the relative ESA sensitivity that reportedly increases with age during early childhood are also noteworthy.11The registry of the International Pediatric Peritoneal Dialysis Network (IPPN) prospectively collects detailed clinical, biochemical, dialysis, and medication-related information (including ESA types and doses and modalities of iron supplementation) from a substantial number of children undergoing long-term PD around the world. In-depth analysis of this unique database has allowed us to (1) gain insight into the demographic characteristics of renal anemia and its treatment in the pediatric PD population worldwide, (2) explore the relationship between ESA dose requirements and body dimensions, (3) identify factors contributing to ESA resistance in children, and (4) associate anemia control with patient outcomes.  相似文献   
54.
55.
Concerns have been raised that mammalian target of rapamycin inhibitors in pediatric transplant recipients might interfere with longitudinal bone growth by inhibition of growth factor signaling and growth plate chondrocyte proliferation. We therefore undertook a prospective nested, case‐control study on longitudinal growth over 2 years in steroid‐free pediatric renal transplant recipients. Fourteen patients on a steroid‐free maintenance immunosuppressive regimen consisting of low‐dose everolimus (EVR) in conjunction with low‐dose cyclosporine (CsA) were compared to a matched cohort of 14 steroid‐free patients on a standard dose mycophenolate mofetil (MMF) regimen in conjunction with a standard dose calcineurin inhibitor (CNI). The mean change in height standard deviation (SD) score in the first study year was 0.31 ± 0.71 SD score in the EVR group compared to 0.31 ± 0.64 SD score in the MMF group (P = 0.20). For the entire study period of 2 years, the change in height SD score in the EVR group was 0.43 ± 0.81 SDS compared to 0.75 ± 0.85 SDS in the MMF group (P = 0.32). The percentage of prepubertal patients experiencing catch‐up growth, defined as an increase in height SD score ≥0.5 in 2 years, was similar in the EVR group (5/8, 65%) and the MMF group (6/8, 75%; P = 1.00). Longitudinal growth over 2 years in steroid‐free pediatric patients on low‐dose EVR and CsA is not different to that of a matched steroid‐free control group on an immunosuppressive regimen with standard‐dose CNI and MMF. Hence, low‐dose EVR does not appear to negatively impact short‐term growth in pediatric renal transplant recipients.  相似文献   
56.
57.

Background

Thoracic and extremity injuries are common in polytraumatized patients. The clavicle limits the upper thoracic cage and connects the body and upper extremities. It is easy to examine and is visible on standard emergency room radiographs. We hypothesize that clavicular fracture in polytrauma patients indicates the presence of further injuries of the upper extremities, head, neck and thorax.

Material and methods

Retrospective study including patients admitted between 2008 and 2012 to a level-I trauma center. Inclusion criteria: ISS?>?16, two or more injured body regions, clavicular fracture. Control group: patients admitted in 2011, ISS?>?16, two or more injured body regions, no clavicular fracture. Patient information was obtained from the patients’ charts; evaluation of radiographic findings was performed; scoring was based on the Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS) AIS/ISS; data were analyzed using Pearson’s correlation and the Mann–Whitney U-test in SPSS (version 11.5.1); graphs were drawn using EXCEL®.

Results

Thirty-four patients with clavicular fracture (C+) and 40 without (C-) were included; the mean ISS was 25 (range 16–57), m?=?70%, f?=?30%; age 43.3 years (range 9–88); clavicular fractures were positively correlated with severe thoracic (p?=?0.011, OR 4.5: KI 1.3–15.3), external (p?<?0.001, OR 9.2: KI 2.7–30.9) and upper extremity injuries (p?<?0.001, OR 33.2: KI 6.9–16.04 resp. p?=?0.004, OR 12.5: KI 1.5–102.9). C?+?showed a lower head/neck AIS (p?=?0.033), higher thorax AIS (p?=?0.04), arm/shoulder AIS (p?=?0.001) and external AIS (0.003) than C-. Mean hospital stay and ICU treatment time were longer in the C?+?group (p?=?0.001 and p?=?0.025 respectively).

Conclusion

A clavicular fracture can be diagnosed easily and may be used as a pointer for further thoracic and upper extremity injuries in polytrauma patients that might have been otherwise missed. Special attention should be paid on second and tertiary survey.
  相似文献   
58.
The most frequent causes of chronic instability of the pubic symphysis are sports-related continual overload and traumatic symphyseal injuries. Acute injury of the pubic symphysis may be the result of external forces acting on the anterior pelvic ring or the result of internal forces, such as those arising during parturition. The postpartum form of instability following a complication-free birth is reversible and usually returns to normal within a few months through strengthening of the pelvic floor muscles. Residual instability of the pubis symphysis is on the whole a rare complication. Although established therapy options for acute symphyseal separation can be found in the literature, there are only a few case reports on chronic symphyseal instability. There are no guidelines on standardized therapy options. This review article examines the etiology, clinical findings, diagnostic techniques and management options for patients suffering from chronic symphyseal instability.  相似文献   
59.

Background

Febrile urinary tract infections (fUTIs) are common after kidney transplantation (KTx); however, prospective data in a multicenter pediatric cohort are lacking. We designed a prospective registry to record data on fUTI before and after pediatric KTx.

Methods

Ninety-eight children (58 boys and 40 girls)?≤?18 years from 14 mid-European centers received a kidney transplant and completed a 2-year follow-up.

Results

Posttransplant, 38.7 % of patients had at least one fUTI compared with 21.4 % before KTx (p?=?0.002). Before KTx, fUTI was more frequent in patients with congenital anomalies of kidneys and urinary tract (CAKUT) vs. patients without (38 % vs. 12 %; p?=?0.005). After KTx, fUTI were equally frequent in both groups (48.7 % vs. 32.2 %; p?=?0.14). First fUTI posttransplant occurred earlier in boys compared with girls: median range 4 vs. 13.5 years (p?=?0.002). Graft function worsened (p?<?0.001) during fUTI, but no difference was recorded after 2 years. At least one recurrence of fUTI was encountered in 58 %.

Conclusion

This prospective study confirms a high incidence of fUTI after pediatric KTx, which is not restricted to patients with CAKUT; fUTIs have a negative impact on graft function during the infectious episode but not on 2-year graft outcome.
  相似文献   
60.

Background

Recognition of the specific cause of posttraumatic knee stiffness is crucial for determining a suitable therapy.

Therapy

Isolated manipulation under anesthesia often has to be critically viewed. Operative treatment for intra-articular causes ranges from arthroscopic methods to open capsulotomy to endoprosthetic replacement. In cases of bony malposition osteotomy is the method of choice to correct the cause of the restriction of motion.
  相似文献   
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