Genomic testing for suspected monogenic kidney disease in children and adults: A health economic evaluation

PURPOSE

To assess the relative cost-effectiveness of genomic testing compared with standard non-genomic diagnostic investigations in patients with suspected monogenic kidney disease from an Australian health care system perspective.

METHODS

Diagnostic and clinical information was used from a national cohort of 349 participants. Simulation modelling captured diagnostic, health, and economic outcomes during a time horizon from clinical presentation until 3 months post-test results based on the outcome of cost per additional diagnosis and lifetime horizon based on cost per quality-adjusted life-year (QALY) gained.

RESULTS

Genomic testing was Australian dollars (AU$) 1600 more costly per patient and led to an additional 27 diagnoses out of a 100 individuals tested, resulting in an incremental cost-effectiveness ratio of AU$5991 per additional diagnosis. Using a lifetime horizon, genomic testing resulted in an additional cost of AU$438 and 0.04 QALYs gained per individual compared with standard diagnostic investigations, corresponding to an incremental cost-effectiveness ratio of AU$10,823 per QALY gained. Sub-group analyses identified that the results were largely driven by the cost-effectiveness in glomerular diseases.

CONCLUSION

Based on established or expected thresholds of cost-effectiveness, our evidence suggests that genomic testing is very likely to be cost saving for individuals with suspected glomerular diseases, whereas no evidence of cost-effectiveness was found for non-glomerular diseases.

Timing of Kidney Replacement Therapy among Children and Young Adults

BACKGROUND

No randomized trials exist to guide the timing of the initiation of KRT in children. We sought to define trends and predictors of the eGFR at initiation of KRT, center-related clinical practice variation, and any association with patient survival.

METHODS

Children and young adults (1-25 years) commencing KRT (dialysis or kidney transplantation) between 1995 and 2018 were included using data from the Australia and New Zealand Dialysis and Transplant Registry. The associations between eGFR on commencing KRT and covariates were estimated using quantile regression. Cox regression was used to estimate the association between eGFR and patient survival. Logistic regression, categorizing eGFR about a value of 10 ml/min per 1.73 m 2 , was used in conjunction with a random effect by center to quantify clinical practice variation.

RESULTS

Overall, 2274 participants were included. The median eGFR at KRT initiation increased from 7 to 9 ml/min per 1.73 m 2 over the study period and the 90th centile from 11 to 17 ml/min per 1.73 m 2 . The effect of era on median eGFR was modified by modality, with a greater increase among those receiving a preemptive kidney transplant (1.0 ml/min per 1.73 m 2 per 5 years; 95% confidence interval [CI], 0.6 to 1.5) or peritoneal dialysis (0.7 ml/min per 1.73 m 2 per 5 years; 95% CI, 0.4 to 0.9) compared with hemodialysis (0.1 ml/min per 1.73 m 2 per 5 years; 95% CI, -0.1 to 0.3). There were 252 deaths (median follow-up 8.5 years, interquartile range 3.7-14.2) and no association between eGFR and survival (hazard ratio, 1.01 per ml/min per 1.73 m 2 ; 95% CI, 0.98 to 1.04). Center variation explained 6% of the total variance in the odds of initiating KRT earlier. This rose to over 10% when comparing pediatric centers alone.

CONCLUSIONS

Children and young adults progressively commenced KRT earlier. This change was more pronounced for children starting peritoneal dialysis or receiving a preemptive kidney transplant. Earlier initiation of KRT was not associated with any difference in patient survival. A substantial proportion of clinical practice variation was due to center variation alone.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_08_08_CJN0000000000000204.mp3.

Effects of enriching IgG concentration in low- and medium-quality colostrum with colostrum replacer on IgG absorption in newborn Holstein calves

Ingestion and absorption of greater quantities of IgG are required to increase serum IgG levels in newborn calves. This could be achieved by adding colostrum replacer (CR) to maternal colostrum (MC). The objective of this study was to investigate whether low and high-quality MC can be enriched with bovine dried CR to achieve adequate serum IgG levels. Male Holstein calves (n = 80; 16/treatment) with birth body weights (BW) of 40 to 52 kg were randomly enrolled to be fed 3.8 L of the following combinations: 30 g/L IgG MC (C1), 60 g/L IgG MC (C2), 90 g/L IgG MC (C3), C1 enriched with 551 g of CR (60 g/L; 30-60CR), or C2 enriched with 620 g of CR (90 g/L: 60-90CR). A subset of 40 calves (8/treatment) had a jugular catheter placed and were fed colostrum containing acetaminophen at a dose of 150 mg/kg of metabolic body weight, to estimate abomasal emptying rate per hour (kABh). Baseline blood samples were taken (0 h), followed by sequential samples at 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, and 48 h relative to initial colostrum feeding. Results for all measurements are presented in the following order, unless otherwise stated: C1, C2, C3, 30-60CR, and 60-90CR. Serum IgG levels at 24 h were different among calves fed C1, C2, C3, 30-60CR, and 60-90CR: 11.8, 24.3, 35.7, 19.9, and 26.9 mg/mL ± 1.02 (mean ± SEM), respectively. Serum IgG at 24 h increased when enriching C1 to 30-60CR, but not from C2 to 60-90CR. Similarly, apparent efficiency of absorption (AEA) values for calves fed C1, C2, C3, 30-60CR, and 60-90CR were different: 42.4, 45.1, 43.2, 36.3, and 33.4% ± 1.93, respectively. Enriching C2 to 60-90CR reduced AEA, and enriching C1 to 30-60CR tended to decrease AEA. The kABh values for C1, C2, C3, 30-60CR, and 60-90CR were also different: 0.16, 0.13, 0.11, 0.09, and 0.09 ± 0.005, respectively. Enriching C1 to 30-60CR or C2 to 60-90CR reduced kABh. However, 30-60CR and 60-90CR have similar kABh compared with a reference colostrum meal (90 g/L IgG, C3). Even though kABh was reduced for 30-60CR, results indicate that C1 has the potential to be enriched and achieve acceptable serum IgG levels at 24 h without affecting AEA.

A clinical approach to tubulopathies in children and young adults

Kidney tubules are responsible for the preservation of fluid, electrolyte and acid-base homeostasis via passive and active mechanisms. These physiological processes can be disrupted by inherited or acquired aetiologies. The net result is a tubulopathy. It is important to make a prompt and accurate diagnosis of tubulopathies in children and young adults. This allows timely and appropriate management, including disease-specific therapies, and avoids complications such as growth failure. Tubulopathies can present with a variety of non-specific clinical features which can be diagnostically challenging. In this review, we build from this common anatomical and physiological understanding to present a tangible appreciation of tubulopathies as they are likely to be clinically encountered among affected children and young adults.

Membranous nephropathy: Clearer pathology and mechanisms identify potential strategies for treatment

Primary membranous nephropathy (PMN) is one of the common causes of adult-onset nephrotic syndrome and is characterized by autoantibodies against podocyte antigens causing in situ immune complex deposition. Much of our understanding of the disease mechanisms underpinning this kidney-limited autoimmune disease originally came from studies of Heymann nephritis, a rat model of PMN, where autoantibodies against megalin produced a similar disease phenotype though megalin is not implicated in human disease. In PMN, the major target antigen was identified to be M-type phospholipase A2 receptor 1 (PLA2R) in 2009. Further utilization of mass spectrometry on immunoprecipitated glomerular extracts and laser micro dissected glomeruli has allowed the rapid discovery of other antigens (thrombospondin type-1 domain-containing protein 7A, neural epidermal growth factor-like 1 protein, semaphorin 3B, protocadherin 7, high temperature requirement A serine peptidase 1, netrin G1) targeted by autoantibodies in PMN. Despite these major advances in our understanding of the pathophysiology of PMN, treatments remain non-specific, often ineffective, or toxic. In this review, we summarize our current understanding of the immune mechanisms driving PMN from animal models and clinical studies, and the implications on the development of future targeted therapeutic strategies.

Predictive Models for Recurrent Membranous Nephropathy After Kidney Transplantation

Recurrent membranous nephropathy (MN) posttransplantation affects 35% to 50% of kidney transplant recipients (KTRs) and accounts for 50% allograft loss 5 y after diagnosis. Predictive factors for recurrent MN may include HLA-D risk alleles, but other factors have not been explored with certainty.

A mutation affecting laminin alpha 5 polymerisation gives rise to a syndromic developmental disorder

Laminin alpha 5 (LAMA5) is a member of a large family of proteins that trimerise and then polymerise to form a central component of all basement membranes. Consequently, the protein plays an instrumental role in shaping the normal development of the kidney, skin, neural tube, lung and limb, and many other organs and tissues. Pathogenic mutations in some laminins have been shown to cause a range of largely syndromic conditions affecting the competency of the basement membranes to which they contribute. We report the identification of a mutation in the polymerisation domain of LAMA5 in a patient with a complex syndromic disease characterised by defects in kidney, craniofacial and limb development, and by a range of other congenital defects. Using CRISPR-generated mouse models and biochemical assays, we demonstrate the pathogenicity of this variant, showing that the change results in a failure of the polymerisation of α/β/γ laminin trimers. Comparing these in vivo phenotypes with those apparent upon gene deletion in mice provides insights into the specific functional importance of laminin polymerisation during development and tissue homeostasis.

Molecular Analysis of Goodpasture's Disease Following Hematopoietic Stem Cell Transplant in a Pediatric Patient, Recalls the Conformeropathy of Wild-Type Anti-GBM Disease

Background: Goodpasture's disease (GP) is mediated by autoantibodies that bind the glomerular and alveolar basement membrane, causing rapidly progressive glomerulonephritis with or without pulmonary hemorrhage. The autoantibodies bind neoepitopes formed upon disruption of the quaternary structure of α345NC1 hexamer, a critical structural domain of α345 collagen IV scaffolds. Hexamer disruption leads to a conformational changes that transitions α3 and α5NC1 subunits into immunogens, however, the trigger remains unknown. This contrasts with another anti-GBM disease, Alports' post-transplant nephritis (APTN), where the pathogenic alloantibody binds directly to native NC1 hexamer. The current report includes the first study of antigenic specificity and allo-incompatability in anti-GBM disease occurring after allogeneic haematopoietic stem cell transplant (HSCT).

Results: The anti-GBM antibodies were found to be directed predominantly against the E_A epitope of the α3 NC1 monomer of collagen IV and developed rapidly in patient serum reaching peak level within 5 weeks. Autoantibody binding to native α345NC1 hexamer was minimal; however, binding was greatly increased upon dissociation of the native hexamer. There were no polymorphic genetic differences between donor and recipient collagen IV genes which would be predicted to cause a significant NC1 conformational change or to provide a target for antibody binding. Both patient and donor possessed the Goodpasture's susceptibility HLA-allele DRB1^*1501.

Conclusions: The current report includes the first in-depth study of allo-incompatability and antigenic specificity in anti-GBM disease occurring after allogeneic haematopoietic stem cell transplant (HSCT). No polymorphic genetic differences were identified between donor and recipient collagen IV genes which would be predicted to provide a target for antibody binding. Furthermore, autoantibody binding to native α345NC1 hexamer was minimal, increasing greatly upon dissociation of the native hexamer, resembling wild-type GP diseases and marking this as the first example of a post-HSCT conformeropathy.

Comprehensive evaluation of a prospective Australian patient cohort with suspected genetic kidney disease undergoing clinical genomic testing: a study protocol

INTRODUCTION

Recent advances in genomic technology have allowed better delineation of renal conditions, the identification of new kidney disease genes and subsequent targets for therapy. To date, however, the utility of genomic testing in a clinically ascertained, prospectively recruited kidney disease cohort remains unknown. The aim of this study is to explore the clinical utility and cost-effectiveness of genomic testing within a national cohort of patients with suspected genetic kidney disease who attend multidisciplinary renal genetics clinics.

METHODS AND ANALYSIS

This is a prospective observational cohort study performed at 16 centres throughout Australia. Patients will be included if they are referred to one of the multidisciplinary renal genetics clinics and are deemed likely to have a genetic basis to their kidney disease by the multidisciplinary renal genetics team. The expected cohort consists of 360 adult and paediatric patients recruited by December 2018 with ongoing validation cohort of 140 patients who will be recruited until June 2020. The primary outcome will be the proportion of patients who receive a molecular diagnosis via genomic testing (diagnostic rate) compared with usual care. Secondary outcomes will include change in clinical diagnosis following genomic testing, change in clinical management following genomic testing and the cost-effectiveness of genomic testing compared with usual care.

ETHICS AND DISSEMINATION

The project has received ethics approval from the Melbourne Health Human Research Ethics Committee as part of the Australian Genomics Health Alliance protocol: HREC/16/MH/251. All participants will provide written informed consent for data collection and to undergo clinically relevant genetic/genomic testing. The results of this study will be published in peer-reviewed journals and will also be presented at national and international conferences.

NAV-KIDS2 trial: protocol for a multi-centre, staggered randomised controlled trial of a patient navigator intervention in children with chronic kidney disease

Background

Chronic kidney disease (CKD) is a devastating illness associated with increased mortality, reduced quality of life, impaired growth, neurocognitive impairment and psychosocial maladjustment in children. There is growing evidence of socioeconomic disparities in health outcomes among children with CKD. Patient navigators are trained non-medical personnel who assist patients with chronic conditions journey through the continuum of care and transit across different care settings. They help vulnerable and underserved populations to better understand their diagnosis, treatment options, and available resources, guide them through complex medical systems, and help them to overcome barriers to health care access. Given the complexity and chronicity of the disease process and concerns that current models of care may not adequately support the provision of high-level care in children with CKD from socioeconomically disadvantaged backgrounds, a patient navigator program may improve the provision of care and overall health of children with CKD.

Methods

The NAV-KIDS² trial is a multi-centre, staggered entry, waitlisted randomised controlled trial assessing the health benefits and costs of a patient navigator program in children with CKD (stages 3–5, on dialysis, and with kidney transplants), who are of low socioeconomic backgrounds. Across 5 sites, 210 patients aged from 3 to 17 years will be randomised to immediate receipt of a patient navigator intervention for 24 weeks or waitlisting with standard care until receipt of a patient navigator at 24 weeks. The primary outcome is child self-rated health (SRH) 6-months after completion of the intervention. Other outcomes include utility-based quality of life, caregiver SRH, satisfaction with healthcare, progression of kidney dysfunction, other biomarkers, missed school days, hospitalisations and mortality. The trial also includes an economic evaluation and process evaluation, which will assess the cost-effectiveness, fidelity and barriers and enablers of implementing a patient navigator program in this setting.

Discussion

This study will provide clear evidence on the effectiveness and cost-effectiveness of a new intervention aiming to improve overall health and well-being for children with CKD from socioeconomically disadvantaged backgrounds, through a high quality, well-powered clinical trial.

Trial registration

Prospectively registered (12/07/2018) on the Australian New Zealand Clinical Trials Registry (ACTRN12618001152213).

Treatment of recurrent focal segmental glomerulosclerosis post-kidney transplantation in Australian and New Zealand children: A retrospective cohort study

Disease recurrence affects around a third of renal transplants for children with FSGS and is associated with poor graft outcomes. Unfortunately, there are no large trials guiding treatment for recurrent FSGS. We aimed to describe current therapies and treatment response for recurrent FSGS in 4 centres in Australia and New Zealand. Data were collected on children (age <18 years) with recurrent FSGS (1990-2015). We reviewed patient charts to obtain clinical information. Ethics approval was obtained from the relevant boards. Complete records were available on 24 patients (62% female, 54% Caucasian). Median time to first recurrence was 4 days (IQR 2-5 days). There were 14 separate treatment regimens, involving an average of 2 agents. The most common therapies were plasma exchange (20/24 patients, 83%), cyclosporin (15/24, 63%), and methylprednisolone (9/24, 38%). Full remission was achieved in 15 (63%), partial remission in 2 (8%), and no remission in 7 (29%) patients. Of the patients with no remission, 5 lost their graft to recurrent disease and 1 to concurrent acute vascular rejection. The plethora of different treatment regimens reflects the poor evidence guiding management for recurrent FSGS. More research is needed to improve outcomes.

Hospital Resource Utilisation by Patients with Community-Acquired Pneumonia

Little data is available on the resource utilisation of patients admitted with Community-Acquired Pneumonia (CAP) in Ireland. A retrospective review of 50 randomly-selected patients admitted to Beaumont Hospital with CAP was undertaken. The mean length of stay of patients with CAP was 12 days (+/- 16 days). All patients were emergency admissions, all had a chest x-ray, a C-reactive protein blood test, and occupied a public bed at some point during admission. Common antimicrobial therapies were intravenous (IV) amoxicillin/clavulanic acid and oral clarithromycin; 60% received physiotherapy. The estimated mean cost of CAP per patient was €14,802.17. Costs arising from admission to hospital with CAP are substantial, but efforts can be undertaken to ensure that resources are used efficiently to improve patient care such as discharge planning and fewer in-hospital ward transfers.

Longitudinal copy number, whole exome and targeted deep sequencing of 'good risk' IGHV-mutated CLL patients with progressive disease

The biological features of IGHV-M chronic lymphocytic leukemia responsible for disease progression are still poorly understood. We undertook a longitudinal study close to diagnosis, pre-treatment and post relapse in 13 patients presenting with cMBL or Stage A disease and good-risk biomarkers (IGHV-M genes, no del(17p) or del(11q) and low CD38 expression) who nevertheless developed progressive disease, of whom 10 have required therapy. Using cytogenetics, fluorescence in situ hybridisation, genome-wide DNA methylation and copy number analysis together with whole exome, targeted deep- and Sanger sequencing at diagnosis, we identified mutations in established chronic lymphocytic leukemia driver genes in nine patients (69%), non-coding mutations (PAX5 enhancer region) in three patients and genomic complexity in two patients. Branching evolutionary trajectories predominated (n=9/13), revealing intra-tumoural epi- and genetic heterogeneity and sub-clonal competition before therapy. Of the patients subsequently requiring treatment, two had sub-clonal TP53 mutations that would not be detected by standard methodologies, three qualified for the very-low-risk category defined by integrated mutational and cytogenetic analysis and yet had established or putative driver mutations and one patient developed progressive, therapy-refractory disease associated with the emergence of an IGHV-U clone. These data suggest that extended genomic and immunogenetic screening may have clinical utility in patients with apparent good-risk disease.

Genomics in the renal clinic - translating nephrogenetics for clinical practice

Genetic Renal Disease (GRD) presents to mainstream clinicians as a mixture of kidney-specific as well as multi-organ entities, many with highly variable phenotype-genotype relationships. The rapid increase in knowledge and reduced cost of sequencing translate to new and additional approaches to clinical care. Specifically, genomic technologies to test for known genes, the development of pathways to research potential new genes and the collection of registry data on patients with mutations allow better prediction of outcomes. The aim of such approaches is to maximise personal and health-system utility from genomics for those affected by nephrogenetic disorders.

Identifying a consistent pattern of neural function in attention deficit hyperactivity disorder: a meta-analysis

BACKGROUND

The neurobiological underpinnings of attention deficit hyperactivity disorder (ADHD) are inconclusive. Activation abnormalities across brain regions in ADHD compared with healthy controls highlighted in task-based functional magnetic resonance imaging (fMRI) studies are heterogeneous. To identify a consistent pattern of neural dysfunction in ADHD, a meta-analysis of fMRI studies using Go/no-go, Stop and N-back tasks was undertaken.

METHOD

Several databases were searched using the key words: 'ADHD and fMRI' and 'ADHD and fMRI task'. In all, 20 studies met inclusion criteria comprising 334 patients with ADHD and 372 healthy controls and were split into N-back, Stop task and Go/no-go case-control groups. Using Signed Differential Mapping each batch was meta-analysed individually and meta-regression analyses were used to examine the effects of exposure to methylphenidate (MPH), length of MPH wash-out period, ADHD subtype, age and intelligence quotient (IQ) differences upon neural dysfunction in ADHD.

RESULTS

Across all tasks less activity in frontal lobe regions compared with controls was detected. Less exposure to treatment and lengthier wash-out times resulted in less left medial frontal cortex activation in N-back and Go/no-go studies. Higher percentage of combined-type ADHD resulted in less superior and inferior frontal gyrus activation. Different IQ scores between groups were linked to reduced right caudate activity in ADHD.

CONCLUSIONS

Consistent frontal deficits imply homogeneous cognitive strategies involved in ADHD behavioural control. Our findings suggest a link between fMRI results and the potentially normalizing effect of treatment and signify a need for segregated examination and contrast of differences in sample characteristics in future studies.

Impact of electronic chemotherapy order forms on prescribing errors at an urban medical center: results from an interrupted time-series analysis

OBJECTIVE

To evaluate the impact of electronic standardized chemotherapy templates on incidence and types of prescribing errors.

DESIGN

A quasi-experimental interrupted time series with segmented regression.

SETTING

A 700-bed multidisciplinary tertiary care hospital with an ambulatory cancer center.

PARTICIPANTS

A multidisciplinary team including oncology physicians, nurses, pharmacists and information technologists.

INTERVENTION(S)

Standardized, regimen-specific, chemotherapy prescribing forms were developed and implemented over a 32-month period.

MAIN OUTCOME MEASURE(S)

Trend of monthly prevented prescribing errors per 1000 chemotherapy doses during the pre-implementation phase (30 months), immediate change in the error rate from pre-implementation to implementation and trend of errors during the implementation phase. Errors were analyzed according to their types: errors in communication or transcription, errors in dosing calculation and errors in regimen frequency or treatment duration. Relative risk (RR) of errors in the post-implementation phase (28 months) compared with the pre-implementation phase was computed with 95% confidence interval (CI).

RESULTS

Baseline monthly error rate was stable with 16.7 prevented errors per 1000 chemotherapy doses. A 30% reduction in prescribing errors was observed with initiating the intervention. With implementation, a negative change in the slope of prescribing errors was observed (coefficient = -0.338; 95% CI: -0.612 to -0.064). The estimated RR of transcription errors was 0.74; 95% CI (0.59-0.92). The estimated RR of dosing calculation errors was 0.06; 95% CI (0.03-0.10). The estimated RR of chemotherapy frequency/duration errors was 0.51; 95% CI (0.42-0.62).

CONCLUSIONS

Implementing standardized chemotherapy-prescribing templates significantly reduced all types of prescribing errors and improved chemotherapy safety.

Red cell exchange transfusion as a rescue therapy for tacrolimus toxicity in a paediatric renal transplant

Tacrolimus is a widely used macrolide immunosuppressant that has a narrow therapeutic index and potential side effects including neurotoxicity. A 20-month-old boy with kidney disease secondary to prune belly syndrome variant, managed on peritoneal dialysis, received a deceased donor transplant. Standard immunosuppression was used. There was good early graft function. Post-transplant he developed fungal peritonitis associated with a significant reduction in graft function and was treated with caspofungin and fluconazole. Despite tacrolimus dose reduction he developed a rapid rise in tacrolimus concentration to a maximum of 72 ng/ml with an otherwise unexplained reduction in consciousness. He underwent a single volume exchange transfusion with packed red cells and 4.5% albumin (ratio 2:1). This resulted in immediate reduction of his tacrolimus concentration from 61.8 ng/ml to 35.2 ng/ml. The neurological deficit rapidly resolved. The fungal peritonitis was eradicated. Renal function recovered from a nadir of eGFR <10 ml/min/1.73 m² to a baseline of 30 ml/min/1.73 m². At 30 months post-transplant the child has creatinine of 1.4 mg/dl (eGFR of 31 ml/min/1.73 m²), and is developmentally appropriate with no neurological deficit. Red cell exchange transfusion is a potentially safe and effective way of managing severe and symptomatic tacrolimus toxicity.

Is laparoscopic donation safe for paediatric recipients?--a study of 85 paediatric recipients comparing open and laparoscopic donor nephrectomy

INTRODUCTION

The safety of adult laparoscopic donor nephrectomy remains controversial with respect to paediatric recipients with few data existing about its efficacy. Small studies have shown no difference in graft survival when compared with open techniques, but previous data from United Network for Organ Sharing suggests a higher incidence of rejection in laparoscopically procured kidneys.

METHODS

We examined the outcome in a total of 85 consecutive paediatric renal recipients, comparing 46 recipients of laparoscopically procured kidneys (performed over a 3-year period, 2004-07) to a historical control of 39 open donor recipients. Thirty-seven laparoscopic donors were by the hand-assisted technique.

RESULTS

Mean recipient age was 9.8 (SD 5.04) years in the laparoscopic group and 10.4 (SD 4.67) years in the open group (P = 0.617). Two patients had delayed graft function in the laparoscopic group (4.3%) and one (2.5%) in the open group (P = 0.562). At 1 year follow-up, there was 100% graft survival in the laparoscopic group compared to 92% (P = 0.093) in the open group. Incidence of biopsy-proven acute rejection within 1 year of transplant was 26% (16 episodes in 12 patients) in the laparoscopic group compared to 41% (29 episodes in 16 patients) in the open group (P = 0.219). There were no deaths in the laparoscopic group but there were three deaths (7.6%) in the open group (P = 0.093).

CONCLUSIONS

Our experience of laparoscopic kidney donation for paediatric recipients suggests excellent outcome with no difference in rejection rate or graft survival compared to open donation. Laparoscopic donation is the optimal method of kidney procurement for paediatric recipients.

Paediatric non-heart-beating renal transplantation

Expanding donor numbers for paediatric transplantation is an urgent, difficult issue. The use of non-heart-beating donor renal transplants has seen a revival in adult practice, with encouraging results. The authors present the first two cases in the UK of paediatric renal transplant from non-heart-beating donors.

FKBPL Regulates Estrogen Receptor Signalling and Determines Response to Endocrine Therapy

Approximately 40% of patients with ER+ breast cancers do not respond to endocrine therapies; furthermore, most tumours eventually become resistant. We have identified a novel Hsp90 co-chaperone and immunophilin, FKBPL, that binds to Hsp90 and affects the stability and signalling of the estrogen receptor (ER) with implications for breast cancer growth and sensitivity to endocrine therapies.Using co-immunoprecipitations, we have demonstrated that FKBPL interacts within Hsp90 complexes associated with the estrogen receptor in MCF-7 cells. Cells stably overexpressing FKBPL become dependent on estrogen for their growth and even in its presence, FKBPL over-expression slows the rate of proliferation of these cells. More importantly, this dependence on estrogen, rendered FKBPL over-expressing cells dramatically more sensitive (up to 90%) to the anti-estrogens, tamoxifen and fulvestrant. Furthermore, knock-down of FKBPL using a targeted siRNA approach, dramatically increased the resistance of these cells to tamoxifen, supporting a role for FKBPL as a determinant of response to endocrine therapies.We have also identified putative estrogen responsive elements within FKBPL's promoter and show that FKBPL is upregulated in response to estrogen suggesting that FKBPL itself is an estrogen responsive gene. As FKBPL levels increased in response to estrogen, ER levels fell; implicating FKBPL in the stabilisation of ER. This is supported by data demonstrating that FKBPL over-expressing cells exhibit decreased levels of ER and cathepsin D, an estrogen responsive gene, critical to breast cancer growth, survival and invasion. Furthermore, knockdown of FKBPL using an siRNA approach increased ER and cathepsin D levels. The regulation of this ER-responsive gene supports a functional role for FKBPL in physiological ER-mediated signalling. FKBPL is also important for the stabilisation of the cyclin dependent kinase inhibitor, p21 (Jascur et al., 2005). We have seen a dramatic fall in p21 levels when FKBPL is knocked down with a targeted siRNA. Loss of p21 has been associated with a tamoxifen growth inducing phenotype and hyperphosphorylation of ER at S118, and with subsequent increased expression of ER-regulated genes. Here we show that ER phosphorylation is increased in FKBPL knockdown cells and decreased in FKBPL over-expressing cells. Together, these data support a model in which high levels of FKBPL would stabilise p21, reducing ER phosphorylation, abrogating tamoxifen-induced agonist potency and so increase sensitivity to the drug.Finally, having established that FKBPL expression may result in p21-mediated growth arrest and sensitisation to endocrine therapies, we hypothesised that FKBPL may have prognostic value that might impact upon tumour proliferative capacity and improve outcome independent of ER status. This was verified in two publically available breast cancer patient cohorts where we demonstrate that high FKBPL expression was correlated with increased overall survival and distant metastasis-free survival.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5126.

A comparative study of adhesion formation and abdominal wall ingrowth after laparoscopic ventral hernia repair in a porcine model using multiple types of mesh

BACKGROUND

The ideal mesh for laparoscopic ventral hernia repair is not yet identified.

METHODS

We laparoscopically placed polypropylene (PPM), expanded polytetrafluoroethylene (ePTFE), and polyester with antiadhesive collagen layer (PCO) in eight pigs using sutures and tacks for fixation. After 28-day survival, we compared adhesion formation, fibrous ingrowth, and shrinkage among the types of mesh.

RESULTS

Mean area of adhesions to PCO (8.25%) was less than that to ePTFE (57.14%, p < 0.001) or PPM (79.38%, p < 0.001). Adhesions peel strength was less for PCO (2.3 N) than for PPM (16.1 N, p < 0.001) or ePTFE (8.8 N, p = 0.02). Peel strength of mesh from the abdominal wall was less for ePTFE (1.3 N/cm of mesh width) than for PCO (2.8 N/cm, p = 0.001) or PPM (2.1 N/cm, p = 0.05). ePTFE area (94.4 cm(2)) was less than that for PCO (118.6 cm(2), p < 0.001) or PPM (140.7 cm(2), p < 0.02).

CONCLUSION

PCO had fewer and less severe adhesions than ePTFE or PPM while facilitating excellent ingrowth of the adjacent parietal tissue.

Construct validity for the LAPSIM laparoscopic surgical simulator

BACKGROUND

The skills required for laparoscopic surgery are amenable to simulator-based training. Several computerized devices are now available. We hypothesized that the LAPSIM simulator can be shown to distinguish novice from experienced laparoscopic surgeons, thus establishing construct validity.

METHODS

We tested residents of all levels and attending laparoscopic surgeons. The subjects were tested on eight software modules. Pass/fail (P/F), time (T), maximum level achieved (MLA), tissue damage (TD), motion, and error scores were compared using the t-test and analysis of variance.

RESULTS

A total of 54 subjects were tested. The most significant difference was found when we compared the most (seven attending surgeons) and least experienced (10 interns) subjects. Grasping showed significance at P/F and MLA (p < 0.03). Clip applying was significant for P/F, MLA, motion, and errors (p < 0.02). Laparoscopic suturing was significant for P/F, MLA, T, TD, as was knot error (p < 0.05). This finding held for novice, intermediate, and expert subjects (p < 0.05) and for suturing time between attending surgeons and residents (postgraduate year [PGY] 1-4) (p < 0.05).

CONCLUSIONS

LAPSIM has construct validity to distinguish between expert and novice laparoscopists. Suture simulation can be used to discriminate between individuals at different levels of residency and expert surgeons.

Childhood immunisation

There is much debate surrounding the topic of immunisation. Helen McCarthy discusses the immunisation process with an emphasis on risk assessment.

Fatal disseminated fusarium infection in acute lymphoblastic leukaemia in complete remission

Fusarium species are increasingly recognised as serious pathogens in the immunocompromised. The outcome in the context of persistent severe neutropenia has been almost universally fatal. However, there have been several case reports of successful treatment if neutrophil recovery can be achieved. This report presents the case of a fatality that occurred despite neutrophil recovery. A 67 year old man developed disseminated fusariosis during the neutropenic phase of induction chemotherapy for acute lymphoblastic leukaemia. Fusarium dimerum was isolated from blood cultures. This species is highly unusual and very few case reports exist in the literature. An initial response to amphotericin treatment coincided with neutrophil recovery but a subsequent relapse occurred, despite adequate neutrophil counts, which proved fatal. It is postulated that reseeding of the blood from an occult site, namely the right vitreum in this case, led to this secondary relapse despite achieving complete leukaemic remission.

Soil fertility limits carbon sequestration by forest ecosystems in a CO2-enriched atmosphere

Northern mid-latitude forests are a large terrestrial carbon sink. Ignoring nutrient limitations, large increases in carbon sequestration from carbon dioxide (CO2) fertilization are expected in these forests. Yet, forests are usually relegated to sites of moderate to poor fertility, where tree growth is often limited by nutrient supply, in particular nitrogen. Here we present evidence that estimates of increases in carbon sequestration of forests, which is expected to partially compensate for increasing CO2 in the atmosphere, are unduly optimistic. In two forest experiments on maturing pines exposed to elevated atmospheric CO2, the CO2-induced biomass carbon increment without added nutrients was undetectable at a nutritionally poor site, and the stimulation at a nutritionally moderate site was transient, stabilizing at a marginal gain after three years. However, a large synergistic gain from higher CO2 and nutrients was detected with nutrients added. This gain was even larger at the poor site (threefold higher than the expected additive effect) than at the moderate site (twofold higher). Thus, fertility can restrain the response of wood carbon sequestration to increased atmospheric CO2. Assessment of future carbon sequestration should consider the limitations imposed by soil fertility, as well as interactions with nitrogen deposition.

Preschool vision screening: outcome of children referred to the hospital eye service

AIMS

To assess the outcome of children referred to the hospital eye service (HES) from an orthoptist based preschool vision screening programme.

METHODS

A retrospective study was conducted of children referred from screening during a 2 year period. Children were screened by community orthoptists at 3 1/2 years of age. The main outcome measures were (1) HES findings for children referred from screening, and (2) visual outcome for amblyopic children after completion of treatment.

RESULTS

The attendance rate at screening was 79.3% (6794 children): 348 children (5.1% of those screened) were referred to the HES. The HES findings were refractive error (32.9%), amblyopia (29.9%), false positive referral (20.1%), strabismus (13.2%), and other ocular disorders (3.9%). The positive predictive value of screening was 79.9%. Screening detected 48 children with straight eyed amblyopia and 43 children with strabismic amblyopia. A visual acuity of 6/9 or better in the amblyopic eye was achieved by 87.2% of straight eyed amblyopes and 64.3% of strabismic amblyopes (chi 2 = 5.27, p = 0.02). Residual amblyopia of 6/24 or worse occurred in only 5.6% of amblyopic children.

CONCLUSION

Most amblyopic children detected by preschool vision screening achieve a good visual outcome with treatment. While treatment earlier in the sensitive period might be expected to give improved results, it remains to be demonstrated that preschool screening results in a better outcome than screening at school entry. Preschool vision screening also detects a significant number of children without amblyopia who have reduced vision due to refractive errors. This group of children must be included in any analysis of the cost effectiveness of preschool vision screening.

Effects of three male reproductive toxicants on rat cauda epididymal sperm motion

The sensitivity of the CellSoft computer-assisted sperm analysis (CASA) system to detect changes in rat sperm motion was evaluated. CASA motion endpoints were measured in cauda epididymal sperm from Long-Evans rats treated with each of three known male reproductive toxicants reported to affect the epididymis and epididymal sperm motility: alpha-chlorohydrin, ornidazole, and trimethylphosphate. Significant changes in endpoints describing sperm swimming vigor (curvilinear velocity and straight-line velocity) and pattern (linearity and amplitude of lateral head displacement) were observed for rats dosed with each agent when evaluations included mean values and other statistical parameters (i.e., percentiles and distributional shape). alpha-Chlorohydrin (ACH) treatment (10 mg/kg/day; 8 days) resulted in reductions in the mean percentage of motile sperm, curvilinear velocity (VCL), straight-line velocity (VSL), lateral head displacement (ALH), and linearity (LIN). Treatment with ornidazole (ONZ) (200 mg/kg/day/14 days) reduced the percentage of motile sperm. Mean VCL, VSL, and ALH were reduced by 400 mg ONZ/kg/day treatment. Trimethylphosphate (TMP) treatment led to (a) a reduction in the 75th and 90th percentiles for ALH (100 mg TMP/kg/day; 5 days) (P < or = 0.04), (b) a reduction in VCL, VSL, and ALH (250 mg TMP/kg/day), (c) a reduction in the percentage of motile cells and in the 10th and 25th percentiles for VSL (600 mg TMP/kg/day), and (d) increases in the 90th percentile for VSL, in the mean, 75th, and 90th percentiles for VCL, and in the 75th and 90th percentiles for ALH (600 mg TMP/kg/day). The general utility of these analytic approaches in reproductive toxicology studies was demonstrated in the observations of effects at or below dose levels previously reported.