The synthetic TRPML1 agonist ML-SA1 rescues Alzheimer-related alterations of the endosomal-autophagic-lysosomal system.

Abnormalities in the endosomal-autophagic-lysosomal (EAL) system are an early event in Alzheimer's disease (AD) pathogenesis. However, the mechanisms underlying these abnormalities are unclear. The transient receptor potential channel mucolipin 1(TRPML1, also known as MCOLN1), a vital endosomal-lysosomal Ca2+ channel whose loss of function leads to neurodegeneration, has not been investigated with respect to EAL pathogenesis in late-onset AD (LOAD). Here, we identify pathological hallmarks of TRPML1 dysregulation in LOAD neurons, including increased perinuclear clustering and vacuolation of endolysosomes. We reveal that induced pluripotent stem cell (iPSC)-derived human cortical neurons expressing APOE ε4, the strongest genetic risk factor for LOAD, have significantly diminished TRPML1-induced endolysosomal Ca2+ release. Furthermore, we found that blocking TRPML1 function in primary neurons by depleting the TRPML1 agonist PI(3,5)P2 via PIKfyve inhibition, recreated multiple features of EAL neuropathology evident in LOAD. This included increased endolysosomal Ca2+ content, enlargement and perinuclear clustering of endolysosomes, autophagic vesicle accumulation and early endosomal enlargement. Strikingly, these AD-like neuronal EAL defects were rescued by TRPML1 reactivation using its synthetic agonist ML-SA1. These findings implicate defects in TRPML1 in LOAD EAL pathogenesis and present TRPML1 as a potential therapeutic target.

Event-free survival of maralixibat-treated patients with Alagille syndrome compared to a real-world cohort from GALA.

BACKGROUND AND AIMS: Alagille syndrome (ALGS) is characterized by chronic cholestasis with associated pruritus and extrahepatic anomalies. Maralixibat, an ileal bile acid transporter inhibitor, is an approved pharmacologic therapy for cholestatic pruritus in ALGS. Since long-term placebo-controlled studies are not feasible or ethical in children with rare diseases, a novel approach was taken comparing 6-year outcomes from maralixibat trials with an aligned and harmonized natural history cohort from the G lobal AL agille A lliance (GALA) study. APPROACH AND RESULTS: Maralixibat trials comprise 84 patients with ALGS with up to 6 years of treatment. GALA contains retrospective data from 1438 participants. GALA was filtered to align with key maralixibat eligibility criteria, yielding 469 participants. Serum bile acids could not be included in the GALA filtering criteria as these are not routinely performed in clinical practice. Index time was determined through maximum likelihood estimation in an effort to align the disease severity between the two cohorts with the initiation of maralixibat. Event-free survival, defined as the time to first event of manifestations of portal hypertension (variceal bleeding, ascites requiring therapy), surgical biliary diversion, liver transplant, or death, was analyzed by Cox proportional hazards methods. Sensitivity analyses and adjustments for covariates were applied. Age, total bilirubin, gamma-glutamyl transferase, and alanine aminotransferase were balanced between groups with no statistical differences. Event-free survival in the maralixibat cohort was significantly better than the GALA cohort (HR, 0.305; 95% CI, 0.189-0.491; p <0.0001). Multiple sensitivity and subgroup analyses (including serum bile acid availability) showed similar findings. CONCLUSIONS: This study demonstrates a novel application of a robust statistical method to evaluate outcomes in long-term intervention studies where placebo comparisons are not feasible, providing wide application for rare diseases. This comparison with real-world natural history data suggests that maralixibat improves event-free survival in patients with ALGS.

Natural history of liver disease in a large international cohort of children with Alagille syndrome: Results from the GALA study.

BACKGROUND AND AIMS: Alagille syndrome (ALGS) is a multisystem disorder, characterized by cholestasis. Existing outcome data are largely derived from tertiary centers, and real-world data are lacking. This study aimed to elucidate the natural history of liver disease in a contemporary, international cohort of children with ALGS. APPROACH AND RESULTS: This was a multicenter retrospective study of children with a clinically and/or genetically confirmed ALGS diagnosis, born between January 1997 and August 2019. Native liver survival (NLS) and event-free survival rates were assessed. Cox models were constructed to identify early biochemical predictors of clinically evident portal hypertension (CEPH) and NLS. In total, 1433 children (57% male) from 67 centers in 29 countries were included. The 10 and 18-year NLS rates were 54.4% and 40.3%. By 10 and 18 years, 51.5% and 66.0% of children with ALGS experienced ≥1 adverse liver-related event (CEPH, transplant, or death). Children (>6 and ≤12 months) with median total bilirubin (TB) levels between ≥5.0 and <10.0 mg/dl had a 4.1-fold (95% confidence interval [CI], 1.6-10.8), and those ≥10.0 mg/dl had an 8.0-fold (95% CI, 3.4-18.4) increased risk of developing CEPH compared with those <5.0 mg/dl. Median TB levels between ≥5.0 and <10.0 mg/dl and >10.0 mg/dl were associated with a 4.8 (95% CI, 2.4-9.7) and 15.6 (95% CI, 8.7-28.2) increased risk of transplantation relative to <5.0 mg/dl. Median TB <5.0 mg/dl were associated with higher NLS rates relative to ≥5.0 mg/dl, with 79% reaching adulthood with native liver ( p < 0.001). CONCLUSIONS: In this large international cohort of ALGS, only 40.3% of children reach adulthood with their native liver. A TB <5.0 mg/dl between 6 and 12 months of age is associated with better hepatic outcomes. These thresholds provide clinicians with an objective tool to assist with clinical decision-making and in the evaluation of therapies.

Impact of Share 35 liver transplantation allocation in Australia and New Zealand.

Patients with high model for end-stage liver disease (MELD) scores waiting for liver transplantation in Australia and New Zealand (ANZ) have had limited access to deceased donor livers and therefore binational sharing of livers, for patients with a MELD score ≥35 was introduced in February 2016. Waiting list mortality, post-transplant outcomes and intention-to-treat survival were compared between patients whose MELD score reached 35 on the waiting list between October 2013 and April 2015 (Pre-Share 35 group, n = 23) and patients who were Share 35 listed between February 2016 and May 2022 (Share 35 group, n = 112). There was significantly reduced waiting list mortality in share 35 listed patients in comparison to the pre-Share 35 group (11.7% vs. 52.2%, OR .120 95% CI .044-.328, P < .001). Post-transplant patient and graft survival were not significantly different between the groups (5-year patient survival 82% vs. 84%, P = .991, 5-year graft survival 82% vs. 76%, P = .543). Intention-to-treat survival was superior in the Share 35 group (HR .302, 95% CI .149-.614, P < .001). Introduction of Share 35 in ANZ resulted in a 78% risk reduction in waiting list mortality, equivalent post-transplant survival and an improvement in intention-to-treat survival.

Ethnicity and socio-economic deprivation in children with intestinal failure in New Zealand: Disparities in incidence, but not in outcomes.

AIMS: The New Zealand National Intestinal Failure and Rehabilitation Service (NZ-NIFRS) was established in October 2015 to gather longitudinal data on the aetiology, clinical course and outcomes of children with intestinal failure (IF). One main objective is to achieve health equity for patients with IF in NZ. METHODS: Clinical outcomes (enteral autonomy, parenteral nutrition (PN) dependence, death or intestinal transplantation) for IF patients diagnosed from October 2015 to 2018 were analysed; comparisons were made by ethnicity and socio-economic status (SES) using published 'prioritised-ethnicity' health data and the NZ index of deprivation, respectively. The Cox proportional-hazards model was used to assess time to enteral autonomy. RESULTS: Of the 208 patients (55.77% male, 43.75% preterm), 170 (81.73%) achieved enteral autonomy and 14 (6.73%) remained PN dependent. Pacific and Maori children accounted for 12.98% and 27.88% of the patient cohort, respectively, compared to 9.46% and 25.65% of the NZ paediatric population. More significantly, IF patients with a high NZ socio-economic deprivation score were overrepresented, with 35.92% in the highest deprivation quintile and 10.19% in the least deprived quintile, compared to 23.53% and 20.31%, respectively, of the NZ paediatric population. There were no significant differences in primary clinical outcomes for any patients based on ethnicity or SES. CONCLUSION: While disparities in ethnicity and social deprivation do exist in the incidence of IF in NZ children, clinical outcomes are similar for children regardless of ethnicity or SES. NZ-NIFRS has achieved one of its core objectives: to achieve health equity for all patients with IF nationwide.

Late airway complications following pediatric liver transplantation: A case series.

BACKGROUND: Late airway complications, as consequence of immunosuppression following pediatric liver transplantation are uncommonly reported. METHODS: In this retrospective case series, we describe two young children presenting with symptoms of airway obstruction, secondary to differing pathologies in the supraglottic airway, as a result of immunosuppression following liver transplantation. RESULTS: Case 1, a 2-year-old girl who presented with stridor 12-months following liver transplantation, was found to have a proliferative soft tissue mass involving the supraglottic larynx. Biopsies were consistent with infiltrative eosinophilic laryngitis and associated eosinophilic esophagitis. Case 2, a 12-month-old female who presented with stridor 5-months following liver transplantation, was found to have an exophytic soft tissue mass involving the supraglottis and hypopharynx. Biopsies revealed polymorphic Epstein-Barr virus (EBV) driven post-transplant lymphoproliferative disease (PTLD). Case 1 was managed with local resection and high dose oral corticosteroids. Case 2 responded to debulking of the necrotic supraglottic mass, reduction of immunosuppression and rituximab. CONCLUSION: A high index of suspicion needs to be maintained for complications of immunosuppression for appropriate diagnosis of airway presentations following pediatric liver transplantation. Further research is necessary to improve early detection and consolidate management strategies for these airway lesions.

Rising Incidence of Inflammatory Bowel Disease in South Asian Children in New Zealand-A Retrospective Population-Based Study.

OBJECTIVES: High rates of inflammatory bowel disease (IBD) are reported in children of South Asian (SA) descent in some western countries. This population-based study describes the incidence and clinical course of IBD in SA children compared to non-South Asian (NSA) children in New Zealand (NZ). METHODS: Children (≤15 years) with new-onset IBD presenting to a centralized tertiary referral center in Auckland, NZ from 2010 to 2020 were identified. Disease phenotype, clinical characteristics, response to exclusive enteral nutrition, clinical remission rates at 3 and 12 months, biologic use, corticosteroid exposure, and disease complications were compared by ethnicity; IBD incidence was calculated. RESULTS: There were 127 (26 SA; 101 NSA) children with Crohn disease, 41 (10 SA; 31 NSA) with ulcerative colitis, and 10 (3 SA; 7 NSA) with IBD-unclassified. IBD incidence in SA and NSA children was 14.1 per 100,000 and 4.3 per 100,000 respectively ( P < 0.001). IBD incidence increased by 5.6% per year ( P = 0.022), due to a greater rise in incidence in SA (SA 16.8% per year, P = 0.015; NSA 4.5% per year, P = 0.317). At presentation, SA children had worse biochemical parameters, severe colitis, and vitamin D deficiency. SA children had lower rates of remission following exclusive enteral nutrition (28.5% vs 65.0%, P < 0.001) or biologic induction (35.7% vs 70.8%, P = 0.020), at 3-month (35.3% vs 69.8%, P < 0.001) and 12-month follow-up (29.4% vs 55.0%, P = 0.005). No significant differences were found in disease location or corticosteroid burden. CONCLUSIONS: Increasing incidence of IBD was disproportionately represented by SA children with more severe disease and lower remission rates following exclusive enteral nutrition or biologic therapy.

Atopy and allergy following solid organ transplantation: A 15-year experience.

AIM: There are increasing reports of atopy/allergy following solid organ transplantation, especially paediatric liver transplantation (LT) with minimal New Zealand (NZ) data. We describe the prevalence of transplant-acquired atopy and allergy (TAA) in NZ paediatric liver transplant recipients, compared to paediatric kidney and adult liver transplants. METHODS: TAA focussed health questionnaires were sent to patients selected from the NZ transplant registry (transplanted between January 2003 and December 2017). Demographic and clinical data were also obtained from electronic health records and follow-up phone calls. RESULTS: A total of 232 patients (62% male) participated (111 adult liver, 82 paediatric liver, 39 paediatric kidney transplant recipients). Tacrolimus was primary immunosuppression for all LT patients; with combined tacrolimus, mycophenolate and corticosteroids for kidney transplants. The number of patients who developed TAA was significantly higher (P < 0.001) in the paediatric LT group (36/82, 44%) compared to adult liver (12/111, 11%) and paediatric kidney transplants (4/39, 10%). Eczema was most common (73%), then IgE-mediated food allergy (FA, 33%), allergic rhinitis (19%) and asthma (17%). Six paediatric LT recipients developed eosinophilic oesophagitis (EoE). Egg was the most common allergen in the IgE-mediated FA group. TAAs were severe enough to warrant a switch from tacrolimus to another agent in seven paediatric LT patients. For paediatric LT patients, female gender and younger age at transplant were risk factors for developing TAA. CONCLUSIONS: TAA is common in paediatric liver transplant recipients, with female gender and younger age at transplant being risk factors identified. This highlights the need for detailed atopic and allergy history to be incorporated in all pre-transplant assessments.

Waterless bathing for inpatients with neurological issues and complex needs.

Waterless bathing techniques can enhance the care of patients with neurological difficulties. Traditional methods can be uncomfortable and time consuming. Hospital-acquired infections in the NHS are a significant concern because of both financial burdens and antibiotic resistance, and preventing them is paramount. ContiTM waterless bathing products help reduce infection risks, save time and improve the patient experience. Four case studies illustrate the application of these techniques in a specialist hospital for people with complex and serious neurological conditions, demonstrating their practicality and efficacy as well as improvements in patient care and infection control within healthcare facilities.

An international multicenter validation study of the Toronto listing criteria for pediatric intestinal transplantation.

Deciding which patients would benefit from intestinal transplantation (IT) remains an ethical/clinical dilemma. New criteria* were proposed in 2015: ≥2 intensive care unit (ICU) admissions, loss of ≥3 central venous catheter (CVC) sites, and persistently elevated conjugated bilirubin (CB ≥ 75 µmol/L) despite 6 weeks of lipid modification strategies. We performed a retrospective, international, multicenter validation study of 443 children (61% male, median gestational age 34 weeks [IQR 29-37]), diagnosed with IF between 2010 and 2015. Primary outcome measure was death or IT. Sensitivity, specificity, NPV, PPV, and probability of death/transplant (OR, 95% confidence intervals) were calculated for each criterion. Median age at IF diagnosis was 0.1 years (IQR 0.03-0.14) with median follow-up of 3.8 years (IQR 2.3-5.3). Forty of 443 (9%) patients died, 53 of 443 (12%) were transplanted; 11 died posttransplant. The validated criteria had a high predictive value of death/IT; ≥2 ICU admissions (p < .0001, OR 10.2, 95% CI 4.0-25.6), persistent CB ≥ 75 µmol/L (p < .0001, OR 8.2, 95% CI 4.8-13.9). and loss of ≥3 CVC sites (p = .0003, OR 5.7, 95% CI 2.2-14.7). This large, multicenter, international study in a contemporary cohort confirms the validity of the Toronto criteria. These validated criteria should guide listing decisions in pediatric IT.

An Atypical Case of Very Early-onset Familial Adenomatous Polyposis Associated With Focal Cortical Dysplasia.

We describe a female toddler with rectal bleeding from extensive colonic polyposis, and diagnosed with familial adenomatous polyposis. She has epilepsy from infancy attributed to focal cortical dysplasia. Hepatoblastoma was diagnosed at 13 months of age. Germline testing detected a pathogenic APC (adenomatous polyposis coli gene) variant. We discuss the anecdotal management of this case, including the clinical utility of genetic confirmation. We review the genotype-phenotype correlation of the APC mutational spectrum, and the existing evidence supporting the hypothesis that cortical dysplasia is part of the APC-related spectrum.

Australasian paediatric gastroenterologist practices of coeliac disease diagnosis before and during the COVID-19 pandemic.

AIM: To explore the perceptions and practices of Australasian paediatric gastroenterologists in diagnosing coeliac disease (CD) before and during the COVID-19 pandemic. METHODS: Paediatric gastroenterologists in Australasia were invited via email to complete an anonymous online questionnaire over a 2-week period in 2021. RESULTS: The questionnaire was completed by 39 respondents: 33 from Australia and six from New Zealand (NZ) equating to a 66% response rate. Thirty-four (87%) of the 39 respondents reported they currently practised non-biopsy diagnosis of CD in eligible children, while the rest diagnosed CD using biopsy confirmation only. All NZ respondents practised non-biopsy CD diagnosis. A majority of responders (76%) who practised non-biopsy CD diagnosis followed the 2020 European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidelines. Twenty-two (56%) respondents reported that they started using a non-biopsy CD diagnosis protocol before the pandemic and did not change their practice during the pandemic, 10 (26%) started diagnosing non-biopsy CD during the pandemic, 5 (13%) stated their practices of CD were not impacted by the pandemic and 2 (5%) did not respond on whether the pandemic changed their practice. CONCLUSION: The majority of Australasian gastroenterologist respondents reported they routinely utilised the 2020 ESPGHAN diagnostic criteria in eligible children; half of them started prior to the pandemic and another quarter started this approach due to the pandemic. A minority of practitioners routinely rely only on biopsy confirmation to diagnose CD.

Bi-allelic CCDC47 Variants Cause a Disorder Characterized by Woolly Hair, Liver Dysfunction, Dysmorphic Features, and Global Developmental Delay.

Ca2+ signaling is vital for various cellular processes including synaptic vesicle exocytosis, muscle contraction, regulation of secretion, gene transcription, and cellular proliferation. The endoplasmic reticulum (ER) is the largest intracellular Ca2+ store, and dysregulation of ER Ca2+ signaling and homeostasis contributes to the pathogenesis of various complex disorders and Mendelian disease traits. We describe four unrelated individuals with a complex multisystem disorder characterized by woolly hair, liver dysfunction, pruritus, dysmorphic features, hypotonia, and global developmental delay. Through whole-exome sequencing and family-based genomics, we identified bi-allelic variants in CCDC47 that encodes the Ca2+-binding ER transmembrane protein CCDC47. CCDC47, also known as calumin, has been shown to bind Ca2+ with low affinity and high capacity. In mice, loss of Ccdc47 leads to embryonic lethality, suggesting that Ccdc47 is essential for early development. Characterization of cells from individuals with predicted likely damaging alleles showed decreased CCDC47 mRNA expression and protein levels. In vitro cellular experiments showed decreased total ER Ca2+ storage, impaired Ca2+ signaling mediated by the IP3R Ca2+ release channel, and reduced ER Ca2+ refilling via store-operated Ca2+ entry. These results, together with the previously described role of CCDC47 in Ca2+ signaling and development, suggest that bi-allelic loss-of-function variants in CCDC47 underlie the pathogenesis of this multisystem disorder.

Trends in Pediatric Intestinal Failure: A Multicenter, Multinational Study.

OBJECTIVES: To assess the natural history and outcomes of children with intestinal failure in a large, multicenter, geographically diverse contemporary cohort (2010-2015) from 6 pediatric intestinal failure programs. STUDY DESIGN: Retrospective analysis of a multicenter intestinal failure cohort (n = 443). Competing-risk analysis was used to obtain cumulative incidence rates for the primary outcome (enteral autonomy, transplantation, or death). The χ2 test and Cox proportional hazard regression were used for bivariate and multivariable analyses. RESULTS: The study cohort comprised 443 patients (61.2% male). Primary etiologies included short bowel syndrome (SBS), 84.9%; dysmotility disorder, 7.2%; and mucosal enteropathy, 7.9%. Cumulative incidences for enteral autonomy, transplantation, and death at 6 years of follow-up were 53.0%, 16.7%, and 10.5%, respectively. Enteral autonomy was associated with SBS, ≥50% of small bowel length, presence of an ileocecal valve (ICV), absence of portal hypertension, and follow-up in a non-high-volume transplantation center. The composite outcome of transplantation/death was associated with persistent advanced cholestasis and hypoalbuminemia; age <1 year at diagnosis, ICV, and intact colon were protective. CONCLUSIONS: The rates of death and transplantation in children with intestinal failure have decreased; however, the number of children achieving enteral autonomy has not changed significantly, and a larger proportion of patients remain parenteral nutrition dependent. New strategies to achieve enteral autonomy are needed to improve patient outcomes.

The impact of COVID-19 in Dravet syndrome: A UK survey.

OBJECTIVES: To understand the risks, impact and outcome of COVID-19 in people affected by Dravet Syndrome (DS). MATERIALS AND METHODS: An anonymous cross-sectional online survey was conducted between June 17 and July 13, 2020, addressed to families of people with DS. RESULTS: A total of 116 responses were collected, from families of children (n = 86; 74%) and adults (30; 26%) with DS. The majority (106; 91%) were shielded at the family home during lockdown. Symptoms compatible with COVID-19 were reported in 22 (19%) individuals. Only four individuals with symptoms had a PCR swab test, none of which was positive. Only one symptomatic person had antibody testing (but not swab testing), which was positive. One person had repeatedly positive swab tests whilst in hospital for renal failure, but had no typical symptoms of COVID-19. In 50% of people with DS who developed possible or probable COVID-19 symptoms, seizure worsening was reported, in terms of increased seizure frequency or duration or both. Medical attention was required in 9/22 (41%), all of whom were children. CONCLUSIONS: In this cohort of people with DS, we observed an infection rate, determined by compatible symptoms, of 19%, with no deaths and benign outcome in most cases despite the underlying complex epilepsy although children often required medical attention. Early adoption of preventative measures, including testing of symptomatic individuals, regular surveillance for people living in residential care facilities, and shielding of individuals with comorbidities increasing the risk of severe outcome, may limit the impact of COVID-19.

The impact of SARS-CoV-2 vaccination in Dravet syndrome: A UK survey.

BACKGROUND: The COVID-19 pandemic led to the urgent need for accelerated vaccine development. Approved vaccines have proved to be safe and well tolerated across millions of people in the general population. Dravet syndrome (DS) is a severe, early onset, developmental and epileptic encephalopathy. Vaccination is a precipitating factor for seizures. While there is no evidence that vaccine-precipitated seizures lead to adverse outcomes in people with DS, fear surrounding vaccination can remain for caregivers of people with DS, in some cases resulting in rejection of recommended vaccinations, leaving individuals more vulnerable to the relevant infections. A greater understanding of the safety profile of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in this vulnerable group will help provide guidance for caregivers and clinicians when considering vaccination. METHODS: A cross-sectional survey regarding COVID-19 and SARS-CoV-2 vaccine, in people with DS, was conducted by Dravet Syndrome UK (DSUK). Concomitantly, a review of individuals with DS who had recently received the SARS-CoV-2 vaccine, and who are resident at the Chalfont Centre for Epilepsy (CCE), or attend epilepsy clinics at the National Hospital for Neurology and Neurosurgery (NHNN), was undertaken. RESULTS: Thirty-eight people completed the DSUK survey. Thirty-seven percent of caregivers reported being concerned about someone with DS receiving the SARS-CoV-2 vaccine; with some reporting that they would decline a vaccine when offered. Seventy-seven percent had not received any advice from a healthcare professional about the SARS-CoV-2 vaccination. 18/38 were eligible for SARS-CoV-2 vaccination, of whom nine had received their first vaccine dose. Combining the results of the DSUK survey and the review of individuals monitored at CCE or NHNN, fifteen people with DS had received their first dose of the SARS-CoV-2 vaccine. 11/15 (73%) reported at least one side effect, the most common being fatigue (6/15; 40%) and fever (6/15; 40%). Three individuals (20%) reported an increase in seizure frequency after the first vaccine dose. No increase in seizure frequency or duration was reported after the second dose. CONCLUSION: Overall, these results suggest that SARS-CoV-2 vaccines are safe and well tolerated in individuals with DS, as they are in most people without DS. In most people with DS, SARS-CoV-2 vaccine does not appear to be associated with an increase in the frequency or duration of seizures, even in those who develop fever post-vaccination. Many caregivers are concerned about a person with DS receiving a SARS-CoV-2 vaccine, with some reporting that they would decline a SARS-CoV-2 vaccine when offered. It is crucial that healthcare professionals are proactive in providing accurate information regarding the risks and benefits of vaccination in this population, given the potential for serious outcomes from infection.

Diagnostic utility of upper and lower gastrointestinal endoscopy for the diagnosis of acute graft-versus-host disease in children following stem cell transplantation: A 12-year experience.

BACKGROUND: Endoscopically obtained mucosal biopsies are the gold standard for diagnosing acute graft-versus-host disease of the gastrointestinal tract (GI-GVHD). There is no consensus on the ideal endoscopic approach in children. We aimed to ascertain which gastrointestinal sites and endoscopic approaches were most helpful for diagnosing acute GVHD and whether clinical symptoms can guide the endoscopic approach. METHOD: A single-center retrospective review of all pediatric stem cell transplants (SCT) between January 1, 2007, and December 31, 2018. Of those with histologically diagnosed GI-GVHD, sensitivities of individual GI sites for making the diagnosis were calculated. Clinical symptoms were compared with GI site yielding diagnosis. RESULTS: 216 allogeneic SCTs were performed in 199 patients. 37 of 52 suspected GI-GHVD cases underwent endoscopy. There was marked variability in the endoscopic approaches chosen. 82% of these cases had lower gastrointestinal symptoms. 21 cases had histologically proven GI-GVHD. 19 (90%) of these had GVHD of non-gastrointestinal sites; 10 (48%) had concurrent infections. The most-sensitive GI sites were the rectosigmoid and duodenum (86% and 76%, respectively). Overall sensitivity of upper GI endoscopy (UGIE) and lower GI endoscopy (LGIE) was 86% and 90%, respectively. There was no statistically significant association between clinical symptoms and site at which histological diagnosis was obtained. CONCLUSION: We observed variability in the endoscopic approach used by clinicians. UGIE and sigmoidoscopy had high sensitivities for diagnosing GVHD, regardless of symptoms. LGIE had minimal additional diagnostic value. This would support a standardized approach with UGIE and sigmoidoscopy for all children with suspected GI-GVHD.

Paediatric eosinophilic oesophagitis in New Zealand: A 3-year prospective study.

AIM: Eosinophilic oesophagitis (EoE) is a rare, chronic, relapsing immune/antigen-mediated disease characterised by symptoms of oesophageal dysfunction, with a paucity of data among New Zealand (NZ) children. This 3-year prospective study aimed to characterise EoE diagnosed nationally and to describe initial treatment strategies adopted. METHODS: Information on new diagnoses of paediatric EoE was obtained via the New Zealand Paediatric Surveillance Unit, through monthly questionnaires. RESULTS: From February 2014 to January 2017, 73 new cases (74% male) of EoE were reported, including 74% NZ European, 10% Asian, 7% Maori, 5% Middle-Eastern and 3% Pacific peoples. Median age of symptom onset was 4 years; dysphagia (48%) was the most common, followed by vomiting/regurgitation (40%), food impaction (19%) and epigastric pain (16%). A co-morbid history of other allergic conditions was present in 62% of patients, and 41% had a first degree relative with atopy. Seventy-nine percent of patients had abnormal endoscopic findings, most commonly linear furrows and white plaques; none had strictures. Median eosinophil count per high-powered field was 40 and 50 in the mid and distal oesophagus, respectively. Fifty-four percent of patients were initially managed with dietary manipulation alone (four required elemental feeds, five nasogastric tubes). Fifty-four percent of patients were treated with swallowed corticosteroids and 7% with prednisone. One patient was also treated with a leukotriene receptor antagonist. CONCLUSION: This first prospective study on paediatric patients with EoE in NZ finds similar demographics and disease characteristics as in other populations despite our unique ethnic population. Long-term prospective observational data should significantly improve our knowledge of this rare condition.

Phase Ib Study of Combination Therapy with MEK Inhibitor Binimetinib and Phosphatidylinositol 3-Kinase Inhibitor Buparlisib in Patients with Advanced Solid Tumors with RAS/RAF Alterations.

BACKGROUND: This multicenter, open-label, phase Ib study investigated the safety and efficacy of binimetinib (MEK inhibitor) in combination with buparlisib (phosphatidylinositol 3-kinase [PI3K] inhibitor) in patients with advanced solid tumors with RAS/RAF alterations. MATERIALS AND METHODS: Eighty-nine patients were enrolled in the study. Eligible patients had advanced solid tumors with disease progression after standard therapy and/or for which no standard therapy existed. Evaluable disease was mandatory, per RECIST version 1.1 and Eastern Cooperative Oncology Group performance status 0-2. Binimetinib and buparlisib combinations were explored in patients with KRAS-, NRAS-, or BRAF-mutant advanced solid tumors until the maximum tolerated dose and recommended phase II dose (RP2D) were defined. The expansion phase comprised patients with epidermal growth factor receptor (EGFR)-mutant, advanced non-small cell lung cancer, after progression on an EGFR inhibitor; advanced RAS- or BRAF-mutant ovarian cancer; or advanced non-small cell lung cancer with KRAS mutation. RESULTS: At data cutoff, 32/89 patients discontinued treatment because of adverse events. RP2D for continuous dosing was buparlisib 80 mg once daily/binimetinib 45 mg twice daily. The toxicity profile of the combination resulted in a lower dose intensity than anticipated. Six (12.0%) patients with RAS/BRAF-mutant ovarian cancer achieved a partial response. Pharmacokinetics of binimetinib were not altered by buparlisib. Pharmacodynamic analyses revealed downregulation of pERK and pS6 in tumor biopsies. CONCLUSION: Although dual inhibition of MEK and the PI3K pathways showed promising activity in RAS/BRAF ovarian cancer, continuous dosing resulted in intolerable toxicities beyond the dose-limiting toxicity monitoring period. Alternative schedules such as pulsatile dosing may be advantageous when combining therapies. IMPLICATIONS FOR PRACTICE: Because dysregulation of the mitogen-activated protein kinase (MAPK) and the phosphatidylinositol 3-kinase (PI3K) pathways are both frequently involved in resistance to current targeted therapies, dual inhibition of both pathways may be required to overcome resistance mechanisms to single-agent tyrosine kinase inhibitors or to treat cancers with driver mutations that cannot be directly targeted. A study investigating the safety and efficacy of combination binimetinib (MEK inhibitor) and buparlisib (PI3K inhibitor) in patients harboring alterations in the RAS/RAF pathway was conducted. The results may inform the design of future combination therapy trials in patients with tumors harboring mutations in the PI3K and MAPK pathways.

Visualisation of cholesterol and ganglioside GM1 in zebrafish models of Niemann-Pick type C disease and Smith-Lemli-Opitz syndrome using light sheet microscopy.

Lysosomal storage diseases are the most common cause of neurodegeneration in children. They are characterised at the cellular level by the accumulation of storage material within lysosomes. There are very limited therapeutic options, and the search for novel therapies has been hampered as few good small animal models are available. Here, we describe the use of light sheet microscopy to assess lipid storage in drug and morpholino induced zebrafish models of two diseases of cholesterol homeostasis with lysosomal dysfunction: First, Niemann-Pick type C disease (NPC), caused by mutations in the lysosomal transmembrane protein NPC1, characterised by intralysosomal accumulation of cholesterol and several other lipids. Second, Smith-Lemli-Opitz syndrome (SLOS), caused by mutations in 7-dehydrocholesterol reductase, which catalyses the last step of cholesterol biosynthesis and is characterised by intralysosomal accumulation of dietary cholesterol. This is the first description of a zebrafish SLOS model. We find that zebrafish accurately model lysosomal storage and disease-specific phenotypes in both diseases. Increased cholesterol and ganglioside GM1 were observed in sections taken from NPC model fish, and decreased cholesterol in SLOS model fish, but these are of limited value as resolution is poor, and accurate anatomical comparisons difficult. Using light sheet microscopy, we were able to observe lipid changes in much greater detail and identified an unexpected accumulation of ganglioside GM1 in SLOS model fish. Our data demonstrate, for the first time in zebrafish, the immense potential that light sheet microscopy has in aiding the resolution of studies involving lysosomal and lipid disorders.