High Body Mass Index and Response to Anti-Tumor Necrosis Factor Therapy in Pediatric Crohn's Disease

INTRODUCTION

Obesity is common among patients with pediatric Crohn's disease (PCD). Some adult studies suggest obese patients respond less well to anti-tumor necrosis factor (TNF) treatment. This study sought compares anti-TNF response and anti-TNF levels between pediatric patients with normal and high body mass index (BMI).

METHODS

The COMBINE trial compared anti-TNF monotherapy with combination therapy with methotrexate in patients with PCD. In this secondary analysis, a comparison of time-to-treatment failure among patients with normal BMI vs BMI Z -score >1, adjusting for prescribed anti-TNF (infliximab [IFX] or adalimumab [ADA]), trial treatment assignment (combination vs monotherapy), and relevant covariates. Median anti-TNF levels across BMI category was also examined.

RESULTS

Of 224 participants (162 IFX initiators and 62 ADA initiators), 111 (81%) had a normal BMI and 43 (19%) had a high BMI. High BMI was associated with treatment failure among ADA initiators (7/10 [70%] vs 12/52 [23%], hazard ratio 0.29, P = 0.007) but not IFX initiators. In addition, ADA-treated patients with a high BMI had lower ADA levels compared with those with normal BMI (median 5.8 vs 12.8 μg/mL, P = 0.02). IFX trough levels did not differ between BMI groups.

DISCUSSION

Overweight and obese patients with PCD are more likely to experience ADA treatment failure than those with normal BMI. Higher BMI was associated with lower drug trough levels. Standard ADA dosing may be insufficient for overweight children with PCD. Among IFX initiators, there was no observed difference in clinical outcomes or drug levels, perhaps due to weight-based dosing and/or greater use of proactive drug monitoring.

The contributions of clinical disease activity, functional disability, and illness intrusiveness to depressive symptoms in pediatric inflammatory bowel disease

BACKGROUND

Clinical disease activity associated with inflammatory bowel disease (IBD) can place physical limitations on youths' activities of daily living. In turn, functional limitations potentially contribute to youths' heightened experience of IBD-induced intrusions on a wide range of routine and valued activities (i.e., illness intrusiveness), which can increase their risk for depressive symptoms. The present study examined the contributions of clinical disease activity, functional disability, and illness intrusiveness to depressive symptoms in youth with IBD.

METHODS

Youth (N = 180) completed the Functional Disability Inventory (FDI), Illness Intrusiveness Scale-Child (IIS-C), and Children's Depression Inventory-2 (CDI-2). Physicians completed the Physicians Global Assessment of disease activity (PGA).

RESULTS

Results revealed a mediating effect for functional disability in the association between disease activity and depressive symptoms (PGA → FDI → CDI-2); illness intrusiveness mediated the association between functional disability and depressive symptoms (i.e., FDI → IIS-C → CDI-2). Serial mediation revealed that clinical disease activity conferred an indirect effect on youth depressive symptoms through the sequential effects of functional disability and illness intrusiveness (i.e., PGA → FDI → IIS-C → CDI-2).

CONCLUSIONS

Taken together, these findings indicate that youth who encounter more physical limitations as a function of clinical disease activity are more likely to experience an amplified sense of IBD-related intrusions on their ability to participate in meaningful activities. In turn, heightened illness intrusiveness increases the likelihood of depressive symptoms. Clinical interventions that help youth maintain adequate functional ability in the face of IBD disease activity and encourage involvement in positively valued activities could decrease the negative impact of IBD on youths' emotional adjustment.

IBD Camp Oasis: A look at Participants' Social-Emotional Well-Being and Protective Factors During Camp and Beyond

Background

Camp Oasis is an annual week-long camp serving children with inflammatory bowel disease (IBD) and hosted by the Crohn's and Colitis Foundation. Youth with IBD are at increased risk for mental health challenges, with Camp Oasis potentially mitigating these risks. The aim of this study is to measure change in and predictors of social-emotional well-being and protective factors of self-worth as a result of attending Camp Oasis.

Methods

Between 2012 and 2019, a voluntary survey was administered to participants and their caregivers to reflect on their perceptions of social/emotional well-being and protective factors related to chronic disease. T-tests compared change in participants' and caregivers' perceptions before and after camp; path analyses examined the key predictors of social-emotional well-being.

Results

A total of 6011 online surveys were analyzed. Participants and caregivers reported consistently positive perceptions of participants' experiences during and after camp. Significant improvements in confidence, independence, activity, comfort around others, being more open about disease, and taking medication as expected were observed. Being new to Camp Oasis was one of the strongest predictors of both disease-related self-efficacy and social connections after camp.

Conclusions

The uniformly high rates of participants' perceptions during camp suggest camp is a life-changing experience for youth with IBD, reduces disease-related stigma, and enhances confidence and social skills. Participants' positive experiences appear to foster notable benefits after camp in terms of openness, their sense of belonging, connections, and confidence.

Use, Durability, and Risks for Discontinuation of Initial and Subsequent Biologics in a Large Pediatric-Onset IBD Cohort

BACKGROUND

Biologic medications are recommended for treatment of moderately-to-severely active Crohn disease (CD) or ulcerative colitis (UC) in children. However, many patients require sequential biologic treatment because of nonresponse or loss of response to the initial biologic.

METHODS

We analyzed pediatric inflammatory bowel disease (IBD) data from the ImproveCareNow Network registry between May 2006 and September 2016, including time to biologic initiation, choice of first subsequent biologics, biologic durability, and reasons for discontinuation.

RESULTS

Of 17,649 patients with IBD [CD: 12,410 (70%); UC: 5239 (30%)], 7585 (43%) were treated with a biologic agent before age 18 (CD: 50%; UC: 25%). Biologic treatment was more likely for CD than UC (odds ratio, 3.0; 95% CI: 2.8-3.2; P < 0.0001). First biologic agents for all patients were anti-tumor necrosis factor agents (88% infliximab, 12% adalimumab). Probability of remaining on the first biologic was significantly higher in CD than UC ( P < 0.0001). First biologics were discontinued because of loss of response (39%), intolerance (23%), and nonresponse (19%). In univariate analysis, factors associated with discontinuation of first and/or second biologics in CD include colonic-only disease, corticosteroid use, upper gastrointestinal tract involvement, and clinical and biochemical markers of severe disease. Biologic durability improved with later induction date.

CONCLUSIONS

Treatment with biologic medications is common in pediatric IBD. Patients with CD are more likely to receive biologics, receive biologics earlier in disease course, and remain on the first biologic longer than patients with UC. Multiple factors may predict biologic durability in children with IBD.

Comparative Effectiveness of Anti-TNF in Combination with Low Dose Methotrexate vs Anti-TNF Monotherapy in Pediatric Crohn's Disease: a Pragmatic Randomized Trial

BACKGROUND AND AIMS

Tumor Necrosis Factor inhibitors (TNFi), including infliximab and adalimumab, are a mainstay of pediatric Crohn's disease (PCD) therapy; however, non-response and loss of response is common. As combination therapy with methotrexate may improve response, we performed a multi-center, randomized, double-blind, placebo-controlled pragmatic trial to compare TNFi with oral methotrexate to TNFi monotherapy.

METHODS

PCD patients initiating infliximab or adalimumab were randomized in 1:1 allocation to methotrexate or placebo and followed for 12-36 months. The primary outcome was a composite indicator of treatment failure. Secondary outcomes included anti-drug antibodies (ADA) and patient reported outcomes (PROs) of pain interference and fatigue. Adverse events (AEs) and Serious AEs (SAEs) were collected.

RESULTS

Of 297 participants (mean age 13.9 years, 35% female), 156 were assigned to methotrexate (110 infliximab initiators and 46 adalimumab initiators) and 141 to placebo (102 infliximab initiators and 39 adalimumab initiators). In the overall population, time to treatment failure did not differ by study arm (HR 0.69, 95% CI 0.45-1.05). Among infliximab initiators, there were no differences between combination and monotherapy (HR 0.93, 95% CI 0.55-1.56). Among adalimumab initiators, combination therapy was associated with longer time to treatment failure (HR 0.40, 95% CI 0.19-0.81). A trend towards lower ADA development in the combination therapy arm was not significant. [(infliximab OR 0.72 (0.49-1.07); adalimumab OR 0.71 (0.24-2.07)]. No differences in PROs were observed. Combination therapy resulted in more AEs but fewer SAEs.

CONCLUSIONS

Among adalimumab but not infliximab initiators, PCD patients treated with methotrexate combination therapy experienced a 2-fold reduction in treatment failure with a tolerable safety profile.

Factor analysis of the stigma scale-child in pediatric inflammatory bowel disease

OBJECTIVE

Illness stigma, or perceived stigma related to a chronic health condition, is pervasive among youth with inflammatory bowel disease (IBD). However, no studies exist examining the psychometric properties of illness stigma measures in this population. Using a modified version of the Child Stigma Scale originally developed for youth with epilepsy, the current study investigated the factor structure and validity of this adapted measure (i.e., Stigma Scale - Child; SS-C) in youth with IBD.

METHODS

Factor analyses were conducted to determine the most parsimonious factor structure for the adapted 8-item Stigma Scale - Child in a sample of 180 youth with IBD. Correlations were conducted to assess convergent validity, and a multiple regression was conducted to further evaluate the measure's predictive validity of child depressive symptoms.

RESULTS

The most parsimonious model for the SS-C is a one-factor solution with an error covariance between the two items assessing concealment/disclosure of IBD diagnosis.

CONCLUSIONS

The SS-C is a psychometrically sound illness stigma measure in pediatric IBD that demonstrates strong convergent validity with psychosocial adjustment factors such as thwarted belongingness, illness uncertainty, and illness intrusiveness, as well as strong predictive validity with youth depressive symptoms. The SS-C is a viable option for use as a brief screener in youth with IBD across clinical and research settings.

The impact of illness intrusiveness and overparenting on depressive symptoms in parents of youth with inflammatory bowel disease

PURPOSE

Inflammatory bowel disease (IBD) management creates significant caregiver demands that can interfere with parents' ability to engage in a number of role functions (i.e., illness intrusiveness) well into their child's adolescence, potentially resulting in excessive or misdirected parenting (i.e., overparenting). Disruptions and limited access to routine and valued activities (e.g., family, work, and leisure) due to IBD and excessive parenting may result in parents neglecting their own personal and emotional self-care needs, increasing their risk for depressive symptoms. To explore these associations, the present study examined parents' experience of illness intrusiveness and subsequent overparenting as serial mediators in the association between disease severity and parent depressive symptoms.

DESIGN AND METHODS

Participants were 146 caregivers of adolescents with IBD from an outpatient pediatric gastroenterology clinic. During a scheduled outpatient visit, parents completed measures of illness intrusiveness, overparenting, and depressive symptoms. Pediatric gastroenterologists provided ratings of disease severity.

RESULTS

Several direct and indirect associations were observed among the modeled variables. Notably, mediation analysis revealed a significant disease severity → illness intrusiveness → overparenting → depressive symptoms serial indirect effect.

CONCLUSIONS

Parents' experience of greater IBD-induced lifestyle disruptions is associated with increased overparenting and a heightened risk for depressive symptoms.

PRACTICE IMPLICATIONS

Parents should be encouraged to establish and maintain a healthy balance between parenting and self-care/role function activities, especially during adolescence when greater youth autonomy and independence are crucial. These types of clinical efforts may reduce the likelihood of parents experiencing depressive symptoms, and have the added benefit of improving adolescent IBD self-management.

Stigma Moderates the Relation Between Peer Victimization, Thwarted Belongingness, and Depressive Symptoms in Youth with Inflammatory Bowel Disease

PURPOSE

The stigmatizing nature of IBD symptoms may place youth at risk for being targets of peer victimization, potentially resulting in a decreased sense of social belongingness and poorer emotional adjustment. The present study tested a series of mediation and moderated mediation models examining the associations among peer victimization, thwarted social belongingness, and depressive symptoms, as well as the moderating role of IBD stigma in these associations. We hypothesized peer victimization would have an indirect effect on youth depressive symptoms through thwarted belongingness, and this effect would be amplified for youth endorsing greater IBD stigma.

DESIGN AND METHODS

Seventy-five youth (10-18 yrs.) diagnosed with IBD were recruited from a pediatric gastroenterology clinic. Participants completed self-report measures of IBD stigma, peer victimization, thwarted belongingness, and depressive symptoms.

RESULTS

As anticipated, mediation analyses revealed a significant peer victimization → thwarted belongingness → depressive symptoms indirect path. Moderated mediation analyses indicated that this indirect effect was moderated by IBD stigma and was significantly greater among youth reporting higher IBD stigma.

CONCLUSIONS

Youth who experience higher levels of IBD-related stigma are at increased risk for depressive symptoms as a function of the socially isolating effects of peer victimization.

PRACTICE IMPLICATIONS

Our findings highlight the need for routine screening and identification of the socioemotional challenges faced by youth with IBD. Clinical interventions that incorporate coping strategies aimed at minimizing youths' stigmatizing self-perceptions and improving overall social skills and social engagement may lessen the negative impact of peer victimization on youths' social and emotional adjustment.

Stigma by Association: Parent Stigma and Youth Adjustment in Inflammatory Bowel Disease

OBJECTIVE

Examine the indirect association between parents' experience of stigma (i.e., associative stigma) and youth depressive symptoms through the serial effects of associative stigma on parent and youth illness intrusiveness in pediatric inflammatory bowel disease (IBD).

METHODS

During routine clinic visits, 150 youth with well-controlled IBD (ages 10-18 years) completed measures of perceived illness intrusiveness and depressive symptoms. Parents completed measures of associative stigma and illness intrusiveness. Pediatric gastroenterologists provided ratings of IBD disease severity.

RESULTS

Structural equation modeling revealed significant direct associations for associative stigma → parent illness intrusiveness, parent illness intrusiveness → youth illness intrusiveness, and youth illness intrusiveness → youth depressive symptoms. Results also revealed a significant associative stigma → parent illness intrusiveness → youth illness intrusiveness→ youth depressive symptoms serial mediation path, indicating that parents' experience of associative stigma indirectly influenced youth depressive symptoms through its sequential effects on parent and youth perceived illness intrusiveness.

CONCLUSIONS

Parents who face stigma related to their child's IBD (i.e., associative stigma) are more likely to experience IBD-induced lifestyle intrusions (i.e., illness intrusiveness), which in turn is associated with youths' illness intrusiveness and ultimately youth depressive symptoms. These findings provide further evidence for the important role of illness-related stigma in pediatric IBD, particularly the transactional relation between parents' associative stigma and youths' illness appraisals and emotional functioning. The clinical implications of our results for addressing adjustment difficulties in youth with IBD are also discussed.

The Contributions of Illness Stigma, Health Communication Difficulties, and Thwarted Belongingness to Depressive Symptoms in Youth with Inflammatory Bowel Disease

OBJECTIVE

Youth with inflammatory bowel disease (IBD) often experience difficulties communicating about their disease. It is suspected that the stigmatizing nature of IBD symptoms contributes to youths' health communication difficulties, leaving youth feeling disconnected from their social environment and potentially resulting in decreased social belongingness and poorer emotional functioning. In this study, we tested an illness stigma → health communication difficulties → thwarted belongingness → depressive symptoms serial mediation model. It was anticipated that youth illness stigma would confer a serial indirect effect on youth depressive symptoms through the sequential effects of stigma on health communication difficulties and thwarted social belongingness.

METHODS

Seventy-five youth with IBD between the ages of 10 and 18 completed measures of perceived illness stigma, health communication difficulties, thwarted belongingness, and depressive symptoms.

RESULTS

Results indicated a significant illness stigma → thwarted belongingness → depressive symptoms simple mediation path. Importantly, findings also revealed a significant serial mediation path for illness stigma → health communication difficulties → thwarted belongingness → depressive symptoms.

CONCLUSIONS

Youth who perceive greater IBD stigma appear to experience increased difficulty communicating about their IBD with others, which in turn is associated with feelings of thwarted social belongingness and ultimately elevated depressive symptoms. These findings suggest that difficulty communicating about IBD is one potential route by which illness stigma has a negative impact on youth adjustment outcomes. Results could also inform clinical interventions to address IBD stigma and health communication difficulties associated with the social and emotional challenges in youth with IBD.

Continued Statural Growth in Older Adolescents and Young Adults With Crohn's Disease and Ulcerative Colitis Beyond the Time of Expected Growth Plate Closure

BACKGROUND

Cessation of statural growth occurs with radiographic closure of the growth plates, radiographically defined as bone age (BA) 15 years in females and 17 in males.

METHODS

We determined the frequency of continued growth and compared the total height gain beyond the time of expected growth plate closure and the chronological age at achievement of final adult height in Crohn's disease (CD) vs ulcerative colitis (UC) and described height velocity curves in inflammatory bowel disease (IBD) compared with children in the National Health and Nutrition Examination Survey (NHANES). We identified all females older than chronological age (CA) 15 years and males older than CA 17 years with CD or UC in the ImproveCareNow registry who had height documented at ≥3 visits ≥6 months apart.

RESULTS

Three thousand seven patients (48% female; 76% CD) qualified. Of these patients, 80% manifested continued growth, more commonly in CD (81%) than UC (75%; P = 0.0002) and in females with CD (83%) than males with CD (79%; P = 0.012). Median height gain was greater in males with CD (1.6 cm) than in males with UC (1.3 cm; P = 0.0004), and in females with CD (1.8 cm) than in females with UC (1.5 cm; P = 0.025). Height velocity curves were shifted to the right in patients with IBD vs NHANES.

CONCLUSIONS

Pediatric patients with IBD frequently continue to grow beyond the time of expected growth plate closure. Unexpectedly, a high proportion of patients with UC exhibited continued growth, indicating delayed BA is also common in UC. Growth, a dynamic marker of disease status, requires continued monitoring even after patients transition from pediatric to adult care.

Comparing machine learning approaches to identify myocardial scar from the ECG

Background

Detection of myocardial infarction (MI) traditionally requires ECG Q waves, which have poor sensitivity, or imaging, which is time consuming. We hypothesized that machine learning (ML) of the ECG could identify prior MI, but its accuracy may depend highly upon the architecture and parameters chosen.

Purpose

To compare ML architectures that predict prior MI from the ECG.

Methods

We curated ECGs in 608 patients seen in cardiology clinics at 2 centers. We transformed 12-lead ECGs to median beats in Frank (X, Y, Z) planes (fig. A). We tested 3 architectures: a 1D deep neural network (DNN), a 3D neural network, and a support vector machine (SVM). The 1D DNN used only temporal convolutions (fig B) while the 3D DNN uses a spatial convolution (fig C) prior to the fully-connected layer (fig. C). Predictive accuracy for history of MI was compared for all architectures (fig. D).

Results

Patients (61.4±14.5 years, 31.2% female) had a 28.7% (175/608) prevalence of prior MI. Optimized SVM of 6 features provided accuracy of 66.1% for identifying prior MI, similar to ECG Q wave analysis. 1D DDN had accuracy of 63.6% with an area under curve (AUC) of 0.625. 3D DNN outperformed 1D DNN and SVM, providing an accuracy of 71±5% (using k=5-fold cross validation), with an AUC of 0.730.

Conclusion

ECG machine learning can identify prior MI better than Q wave analysis, but is sensitive to technical parameters and specific computational architecture. It is important to develop a framework to enable robust comparisons of different ML studies and future refinements.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institutes of Health - United States

Genetic Consequences of the Transatlantic Slave Trade in the Americas

According to historical records of transatlantic slavery, traders forcibly deported an estimated 12.5 million people from ports along the Atlantic coastline of Africa between the 16th and 19th centuries, with global impacts reaching to the present day, more than a century and a half after slavery's abolition. Such records have fueled a broad understanding of the forced migration from Africa to the Americas yet remain underexplored in concert with genetic data. Here, we analyzed genotype array data from 50,281 research participants, which-combined with historical shipping documents-illustrate that the current genetic landscape of the Americas is largely concordant with expectations derived from documentation of slave voyages. For instance, genetic connections between people in slave trading regions of Africa and disembarkation regions of the Americas generally mirror the proportion of individuals forcibly moved between those regions. While some discordances can be explained by additional records of deportations within the Americas, other discordances yield insights into variable survival rates and timing of arrival of enslaved people from specific regions of Africa. Furthermore, the greater contribution of African women to the gene pool compared to African men varies across the Americas, consistent with literature documenting regional differences in slavery practices. This investigation of the transatlantic slave trade, which is broad in scope in terms of both datasets and analyses, establishes genetic links between individuals in the Americas and populations across Atlantic Africa, yielding a more comprehensive understanding of the African roots of peoples of the Americas.

Distinct Cutoff Values of Adalimumab Trough Levels Are Associated With Different Therapeutic Outcomes in Patients With Inflammatory Bowel Disease

Background and Aims

We aimed to evaluate the relationship of serum adalimumab trough levels (ATL) with disease activity of inflammatory bowel disease (IBD) patients in a large, well-characterized referral center-based cohort.

Methods

We compared serum ATL between those with clinical, biochemical, or endoscopic/radiologic disease activity and those without.

Results

A total of 236 patients with IBD were included. Higher cutoff levels were associated with endoscopic and/or radiologic responses (cutoff value: 5.3 mcg/mL, P = 0.003) compared with improvement in C-reactive protein (cutoff value: 4.3 mcg/mL, P = 0.031).

Conclusions

Higher cutoff ATL was associated with endoscopic and/or radiologic response.

Palliative care for cancer patients near end of life in acute-care hospitals across Canada: a look at the inpatient palliative care code

Hospitals play an important role in the care of patients with advanced cancer: nearly half of all cancer deaths occur in acute-care settings. The need for increasing access to palliative care and related support services for patients with cancer in acute-care hospitals is therefore growing. Here, we examine how often and how early in their illness patients with cancer might be receiving palliative care services in the 2 years before their death in an acute-care hospital in Canada. The palliative care code from inpatient administrative databases was used as a proxy for receiving, or being referred for, palliative care. Currently, the palliative care code is the only data element routinely collected from patient charts that allows for the tracking of palliative care activity at a pan-Canadian level. Our findings suggest that most patients with cancer who die in an acute-care hospital receive a palliative designation; however, many of those patients are identified as palliative only in their final admission before death. Of the patients who received a palliative designation before their final admission, nearly half were identified as palliative less than 2 months before death. Findings signal that delivery of services within and between jurisdictions is not consistent, that the palliative care needs of some patients are being missed by physicians, and that palliative care is still largely seen as end-of-life care and is not recognized as an integral component of cancer care. Measuring the provision of system-wide palliative care remains a challenge because comprehensive national data about palliative care are not currently reported from all sectors. To advance measurement and reporting of palliative care in Canada, attention should be focused on collecting comparable data from regional and provincial palliative care programs that individually capture data about palliative care delivery in all health care sectors.

Acute-Care Hospital Use Patterns Near End-of-Life for Cancer Patients Who Die in Hospital in Canada

Background: Acute-care hospitals have a role in managing the needs of people with cancer when they are at the end-of-life; however, overutilization of hospital care at the end-of-life results in poorer quality of life and can worsen the patient's experience. Early integration of comprehensive palliative care can greatly reduce unplanned visits to the emergency department, reduce avoidable admissions to hospital, shorten hospital stays, and increase the number of home deaths as well as improve the quality of life of patients with advanced cancer. Aim: To describe the current landscape of acute-care hospital utilization near the end-of-life across Canada and indirectly examine access to palliative care in cancer patients who die in hospital. Methods: Data were obtained from the Canadian Institute for Health Information. The analysis was restricted to adults aged 18+ who died in an acute care hospital in 2014/15 and 2015/16 for nine provinces and three territories. The Discharge Abstract Database was used to extract acute-care cancer death abstracts. Data on intensive care unit (ICU) admissions includes only facilities that report ICU data. Results: Acute care utilization at end-of-life remains commonplace. In Canada (excluding Québec), 43% (48,987) of deaths from cancer occurred in acute-care hospitals, with 70% admitted through the emergency department (ED). In the last six months of life, cancer patients dying in hospital had a median cumulative length of stay ranging from 17 to 25 days, depending on the province. Between 18.1% and 32.8% of patients experienced two or more admissions to the hospital in the last month of life. The proportion of cancer patients admitted to the ICU in the last 14 days of life ranged from 6.4% to 15.1%. Patient demographics (age, sex, place of residence) and clinical factors (cancer type) were often predictors of hospital utilization at end-of-life and likely point to inequities in access to palliative and end-of-life care. Conclusion: Despite previous patient surveys indicating that patients would prefer to receive care and spend their finals days at home or in a hospice, there appears to be overuse of and overreliance on acute care hospital services near the end-of-life in Canada. The high rates of hospital deaths and admissions through the ED at the end-of-life for cancer patients may signal a lack of planning for impeding death and inadequate availability of or access to community- and home-based palliative and end-of-life care services. Acute care hospitals may have a role in managing the health care needs of people affected by cancer; however, end-of-life care should be an option in other settings that align with patient preferences. Standards or practice guidelines to identify, assess and refer patients to palliative care services earlier in their cancer journey should be developed and implemented to ensure optimal quality of life.

Geographic Variation in Colorectal Cancer Incidence and the Disparities in the Prevalence of Modifiable Risk Factors Across Canada

Background: Colorectal cancer is the third most common cancer worldwide. There is wide geographic variation in incidence with rates varying ten-fold between high- and low-income countries. This heavy burden can be mitigated given previous research has estimated that nearly half of all colorectal cancer cases could have been prevented through healthier diets and physically active lifestyles. In Canada, there is considerable geographic variation in age-adjusted incidence rates for colorectal cancer between jurisdictions, greater than that seen for many other cancers. These wide variations likely reflect differences in the prevalence of risk factors across provinces and territories. Aim: To describe the extent of the variation in colorectal cancer incidence rates across Canada and the disparities in the prevalence of modifiable risk factors across jurisdictions known to contribute to this burden. Methods: Colorectal cancer incident cases were obtained from the Canadian Cancer Registry; 2014 was used for provinces (except Quebec where 2010 was the most recent year available) and years 2012 to 2014 were combined to achieve more stable rates for the territories, which are much smaller in population. Data on four known modifiable risk factors for colorectal cancer (excess weight, physical inactivity, alcohol intake and low fruit and vegetable consumption) were obtained from the 2015-16 combined Canadian Community Health Survey. Results: Findings suggest that there is a north-south and east-west gradient in colorectal cancer modifiable risk factors in Canada. For instance, the percentage of adults with excess body weight ranged from 56.8% in British Columbia (west) to 73.1% in New Brunswick (east) and the percentage of adults not meeting physical activity guidelines ranged from 31.8% in Yukon (north) to 50.3% in New Brunswick (east). Generally, this pattern also reflects colorectal cancer incidence rates. The highest prevalence of modifiable risk factors and rates of colorectal cancer are typically in the northern (territories) and eastern provinces of Canada. Conclusion: The global burden of colorectal cancer is expected to increase by nearly 60% by 2030; therefore, targeted interventions are needed to ensure there is not a widening gap in colorectal cancer burden worldwide. Based on current knowledge, the most effective approaches to reduce the burden of colorectal cancer include: 1) adopting public policies that make healthy choices easier and create healthier environments where people live, work and play, and 2) continuing emphasis on screening and early detection. Strategic approaches to addressing modifiable risk factors, as well as mechanisms for detecting colorectal cancer before it develops, have the potential to translate into positive effects on population health and less people developing and dying from cancer.

The north-south and east-west gradient in colorectal cancer risk: a look at the distribution of modifiable risk factors and incidence across Canada

Colorectal cancer (crc) is the 2nd most common cancer in Canada and the 2nd leading cause of cancer death. That heavy burden can be mitigated given the preventability of crc through lifestyle changes and screening. Here, we describe the extent of the variation in crc incidence rates across Canada and the disparities, by jurisdiction, in the prevalence of modifiable risk factors known to contribute to the crc burden. Findings suggest that there is a north-south and east-west gradient in crc modifiable risk factors, including excess weight, physical inactivity, excessive alcohol consumption, and low fruit and vegetable consumption, with the highest prevalence of risk factors typically found in the territories and Atlantic provinces. In general, that pattern reflects the crc incidence rates seen across Canada. Given the substantial interjurisdictional variation, more work is needed to increase prevention efforts, including promoting a healthier diet and lifestyle, especially in jurisdictions facing disproportionately higher burdens of crc. Based on current knowledge, the most effective approaches to reduce the burden of crc include adopting public policies that create healthier environments in which people live, work, learn, and play; making healthy choices easier; and continuing to emphasize screening and early detection. Strategic approaches to modifiable risk factors and mechanisms for early cancer detection have the potential to translate into positive effects for population health and fewer Canadians developing and dying from cancer.

Grafting of Ring-Opened Cyclopropylamine Thin Films on Silicon (100) Hydride via UV Photoionization

The grafting of cyclopropylamine onto a silicon (100) hydride (Si-H) surface via a ring-opening mechanism using UV photoionization is described here. In brief, radicals generated from the Si-H surface upon UV irradiation were found to behave in classical hydrogen abstraction theory manner by which the distal amine group was first hydrogen abstracted and the radical propagated down to the cyclopropane moiety. This subsequently liberated the strained bonds of the cyclopropane group and initiated the surface grafting process, producing a thin film approximately 10-15 nm in height. Contact angle measurements also showed that such photoionization irradiation had yielded an extremely hydrophilic surface (∼21.3°) and X-ray photoelectron spectroscopy also confirmed the coupling was through the Si-C linkage. However, when the surface underwent high-temperature hydrosilylation (>160 °C), the reaction proceeded predominantly through the nucleophilic NH₂ group to form a Si-N linkage to the surface. This rendered the surface hydrophobic and hence suggested that the Si-H homolysis model may not be the main process. To the best of our knowledge, this was the first attempt reported in the literature to use photoionization to directly graft cyclopropylamine onto a silicon surface and in due course generate a highly rich NH-terminated surface that was found to be highly bioactive in promoting cell viability on the basis of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide studies.

Psoriasis and Psoriasiform Eruptions in Pediatric Patients with Inflammatory Bowel Disease Treated with Anti-Tumor Necrosis Factor Alpha Agents

BACKGROUND

Anti-tumor necrosis factor alpha (TNF-α) agents are used to treat a variety of autoimmune and inflammatory conditions, including psoriasis. Paradoxically, numerous reports have documented new-onset or exacerbation of psoriasis or psoriasiform skin lesions (PSO) in patients treated with these agents for conditions other than PSO-particularly in adults with inflammatory bowel disease (IBD). Not much is known regarding similar cases in children.

METHODS

A retrospective chart review was performed on children younger than 19 years of age with IBD seen at the Mayo Clinic between 2003 and 2015 who developed new-onset or recurrent PSO while undergoing anti-TNF-α therapy.

RESULTS

Fourteen children developed PSO while undergoing anti-TNF-α therapy for IBD. All three anti-TNF-α agents (infliximab, adalimumab, certolizumab) used to treat IBD in this series led to induction or recurrence of PSO lesions. The median time to development of PSO was 11 months (range 0-48 mos), the median age was 15 years (range 12.5-17.5 yrs), and 57% of patients were male. IBD activity was quiescent in 93% of cases at PSO onset. Seven patients (50%) discontinued their initial anti-TNF-α therapy because of their skin disease. Ultimately, four patients (29%) had to discontinue all anti-TNF-α therapy to induce PSO resolution.

CONCLUSION

TNF-α antagonist-induced PSO in children with IBD is a rarely reported adverse reaction. PSO onset has a variable latency, but usually occurs during IBD remission, with a slight male bias. Nearly half of patients required a change in their initial anti-TNF-α agent despite conventional skin-directed therapies, and one-third of patients discontinued all anti-TNF-α therapy because of PSO.

Joint Hypermobility Syndrome and Anxiety Disorder: Structural Brain Correlates

Introduction

Joint hypermobility syndrome/Ehlers Danlos III (JHS/EDS III) is a common, connective tissue condition. This group is over-represented in panic/anxiety disorders and exhibits autonomic abnormalities and heightened interoceptive sensibility. Previous neuroimaging in healthy volunteers with hypermobility has observed differences in key emotional brain regions, notably amygdala and insula.

Aims and objective To explore, in a clinical population, the structural brain correlates underpinning the association between JHS/EDS III and anxiety.

Method

Seventy participants were divided into four experimental groups: (2 × 2 factor design: presence/absence of hypermobility; presence/absence of anxiety). Hypermobility was assessed using Brighton Criteria. All participants underwent brief tests of autonomic function and interoception. Structural images were obtained using a 1.5 T MRI scanner. Results are reported at whole brain uncorrected significance threshold of P < 0.001.

Results

Comparison of grey matter volume revealed increased insular volume in anxious patients with JHS/EDS-III compared to anxious patients without (Fig. 1A, B), correlating with initial peak heart rate on standing. Additionally, amygdala volume correlated with hypermobility score in anxious patients, but not in non-anxious individuals (Fig. 1C, D). Amygdala volume correlated with interoceptive accuracy.

Conclusions

This data implicates amygdala and insula as likely neural substrates mediating clinical relationships between hypermobility syndrome and anxiety, demonstrating the relevance of autonomic and interoceptive influences on this relationship. Further work hopes to explore functional and structural connectivity between these regions in JHS/EDS-III.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Long-term outcomes of ileal pouch-anal anastomosis for pediatric chronic ulcerative colitis

BACKGROUND

Ileal pouch-anal anastomosis (IPAA) is the surgical treatment of choice for patients with chronic ulcerative colitis (CUC). In the pediatric population, short-term outcomes of IPAA are excellent but long-term data limited. The purpose of this study is to report long-term functional and quality of life outcomes of IPAA in pediatric patients.

METHODS

Functional outcomes and quality of life (QoL) following IPAA in patients ≤ 18 years of age were prospectively assessed by survey over a 30 year period. Preoperative information, chronic pouchitis and pouch loss were retrospectively reviewed.

RESULTS

Over 30 years, 202 children with CUC underwent IPAA. Questionnaires were returned by 87% and median (range) survey follow-up was 181.5 (7.8-378.5) months. Postoperative day and night-time stool frequency did not increase over time though incontinence increased slightly. Quality of life (QoL) was generally excellent and stable over time. Crohn's disease (CD) was diagnosed in 33 (16%) patients during the follow-up period. Chronic pouchitis occurred in 22 patients and pouch failure in 13 patients. Kaplan Meier estimates of pouch survival at 20 years were 61% for patients with CD and 92% for CUC.

CONCLUSIONS

Ileal pouch-anal anastomosis has long-term durability as a cure for pediatric chronic ulcerative colitis, with most patients reporting stable bowel function and QoL. Chronic pouchitis and pouch failure affect a minority of patients and require further study.

Effectiveness of anti-TNFα for Crohn disease: research in a pediatric learning health system

OBJECTIVES

ImproveCareNow (ICN) is the largest pediatric learning health system in the nation and started as a quality improvement collaborative. To test the feasibility and validity of using ICN data for clinical research, we evaluated the effectiveness of anti-tumor necrosis factor-α (anti-TNFα) agents in the management of pediatric Crohn disease (CD).

METHODS

Data were collected in 35 pediatric gastroenterology practices (April 2007 to March 2012) and analyzed as a sequence of nonrandomized trials. Patients who had moderate to severe CD were classified as initiators or non-initiators of anti-TNFα therapy. Among 4130 patients who had pediatric CD, 603 were new users and 1211 were receiving anti-TNFα therapy on entry into ICN.

RESULTS

During a 26-week follow-up period, rate ratios obtained from Cox proportional hazards models, adjusting for patient and disease characteristics and concurrent medications, were 1.53 (95% confidence interval [CI], 1.20-1.96) for clinical remission and 1.74 (95% CI, 1.33-2.29) for corticosteroid-free remission. The rate ratio for corticosteroid-free remission was comparable to the estimate produced by the adult SONIC study, which was a randomized controlled trial on the efficacy of anti-TNFα therapy. The number needed to treat was 5.2 (95% CI, 3.4-11.1) for clinical remission and 5.0 (95% CI, 3.4-10.0) for corticosteroid-free remission.

CONCLUSIONS

In routine pediatric gastroenterology practice settings, anti-TNFα therapy was effective at achieving clinical and corticosteroid-free remission for patients who had Crohn disease. Using data from the ICN learning health system for the purpose of observational research is feasible and produces valuable new knowledge.

Clinical features and treatment responses in pediatric lymphocytic and collagenous colitis

OBJECTIVE

Microscopic colitis (MC) is prevalent in adults investigated for chronic watery diarrhea, yet characterization of pediatric MC is limited.

METHODS

Our pathology database was searched from 1995 to 2011 for pediatric cases of lymphocytic colitis (LC) or collagenous colitis (CC). Those with diarrhea persisting for >2 weeks and visually normal colonoscopy were accepted as cases. Demographics, laboratory results, medication use within 3 months of presentation, medical and family history of autoimmune disease, and response to treatment were abstracted.

RESULTS

A total of 27 cases were histologically consistent with MC on biopsy; 5 with concomitant enteric infection or isolated abdominal pain were excluded. Twenty-two cases of MC (female patients, 59%; median age at diagnosis, 15.3 years) were included (19 LC and 3 CC). Two had type 1 diabetes mellitus, 2 were anti-nuclear antibody positive, and 2 had common variable immunodeficiency. Of 20 patients who underwent an esophagogastroduodenoscopy, 1 had collagenous sprue and 4 had celiac disease. One presented after the clearance of recurrent Clostridium difficile infection. Previous drug exposures included nonsteroidal anti-inflammatory drugs (n = 7), proton pump inhibitors (n = 6), and selective serotonin reuptake inhibitors (n = 3). Common symptoms in addition to diarrhea included abdominal pain (77.3%) and weight loss (27.3%). Of 17 patients with follow-up, all of the 8 treated with steroids had some response: 57.1% (4/7) responded to mesalamine and 42.9% (3/7) responded to bismuth subsalicylate.

CONCLUSIONS

In this cohort of pediatric patients, LC was much more common than CC. As described in adults, we observed associations with celiac disease, type 1 diabetes mellitus, and medications; we additionally saw an association with immunodeficiency. Our patients showed greater response to steroids than mesalamine or bismuth.

Getting under—and through—the skin: ecological genomics of chytridiomycosis infection in frogs

Amphibian species around the world are currently becoming endangered or lost at a rate that outstrips other vertebrates—victims of a combination of habitat loss, climate change and susceptibility to emerging infectious disease (Stuart et al. 2004). One of the most devastating such diseases is caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), which infects hundreds of amphibian species on multiple continents. While Bd itself has been characterized for some time, we still know little about the mechanisms that make it so deadly. In this issue of Molecular Ecology, Rosenblum et al. describe a genomic approach to this question, reporting the results of a genome-wide analysis of the transcriptional response to Bd in the liver, skin and spleen of mountain yellow-legged frogs (Rana mucosa and R. sierrae: Fig. 1) (Rosenblum et al. 2012). Their results indicate that the skin is not only the first, but likely the most important, line of defence in these animals. Strikingly, they describe a surprisingly modest immune response to infection in Rana, a result that may help explain variable Bd susceptibility across populations and species.

Pediatric chronic ulcerative colitis: does infliximab increase post-ileal pouch anal anastomosis complications?

BACKGROUND

Total proctocolectomy with ileal pouch anal anastomosis (IPAA) is a common surgical approach to chronic ulcerative colitis (CUC). Preoperative use of Infliximab (IFX) has raised concern of increased postoperative complications. We sought to compare outcomes of pediatric patients (≤ 18 years) who were treated with IFX before IPAA to those who did not.

METHODS

Patients (≤ 18 years of age) who underwent IPAA from 2003 to 2008 for CUC were included, and their records were retrospectively reviewed for preoperative medications, operative technique, and 1-year postoperative complications (leak, wound infection, small bowel obstruction, pouchitis). Subjects were divided into 2 groups--those who received IFX preoperatively and those who did not.

RESULTS

Eleven patients received IFX preoperatively, and 27 children did not. All complications following IPAA were more frequent in the IFX group compared to controls (55% vs 26%). Small bowel obstruction was significantly higher in the IFX group (55% vs 7%). Long-term complications occurred in 64% of the IFX group and 61% of the controls.

CONCLUSION

Children that were treated with IFX prior to IPAA suffered twice as many postoperative complications. Long-term outcomes are similar. Currently, we recommend colectomy with end ileostomy for patients that receive IFX within 8 weeks of colectomy for CUC.

Single-incision laparoscopic colon and rectal surgery for pediatric inflammatory bowel disease and polyposis syndromes

BACKGROUND

Minimally invasive procedures for inflammatory bowel disease have been shown to improve recovery in children. We report our initial experience with single-incision laparoscopic operations for pediatric intestinal disease.

METHODS

We retrospectively reviewed 12 procedures in 11 patients (4 women) from March 2010 to January 2011. Procedures were conducted by using standard laparoscopic instruments.

RESULTS

Mean age was 15 years (9-17 years). Procedures included three total abdominal colectomies, four two-stage ileal-pouch anal anastomosis (IPAA), two single-stage IPAA, two three-stage IPAA, and one ileocectomy. An accessory umbilical port was used in 6 cases. Mean operating time was 287 minutes. Mean length of stay was 4.1 days (3-9 days). Postoperative complications have occurred in 5 patients (42%). Anastomotic leak occurred in 2 patients with IPAA without protective ileostomy, 1 operative small bowel obstruction, 1 pelvic abscess and portal vein thrombosis, and 1 readmission for dehydration. Both patients who had leaked have recovered well and had their stomas reversed. Mean follow-up is 190 days. Average number of daily bowel movements is 4.5. Pouchitis has occurred in 50% (4/8) of patients.

CONCLUSIONS

Single-incision laparoscopic surgery for pediatric intestinal disease is safe and feasible by using standard laparoscopic instruments. We do not advocate IPAA without a stoma due to the high rate of anastomotic leak. Continued experience will shorten operative times and reduce complications.

Genetic structure in a dynamic baboon hybrid zone corroborates behavioural observations in a hybrid population

Behaviour and genetic structure are intimately related: mating patterns and patterns of movement between groups or populations influence the movement of genetic variation across the landscape and from one generation to the next. In hybrid zones, the behaviour of the hybridizing taxa can also impact the incidence and outcome of hybridization events. Hybridization between yellow baboons and anubis baboons has been well documented in the Amboseli basin of Kenya, where more anubis-like individuals tend to experience maturational and reproductive advantages. However, it is unknown whether these advantages are reflected in the genetic structure of populations surrounding this area. Here, we used microsatellite genotype data to evaluate the structure and composition of baboon populations in southern Kenya. Our results indicate that, unlike for mitochondrial DNA, microsatellite-based measures of genetic structure concord with phenotypically based taxonomic distinctions and that the currently active hybrid zone is relatively narrow. Isolation with migration analysis revealed asymmetric gene flow in this region from anubis populations into yellow populations, in support of the anubis-biased phenotypic advantages observed in Amboseli. Populations that are primarily yellow but that receive anubis gene flow exhibit higher levels of genetic diversity than yellow populations far from the introgression front. Our results support previous work that indicates a long history of hybridization and introgression among East African baboons. Specifically, it suggests that anubis baboons are in the process of gradual range expansion into the range of yellow baboons, a pattern potentially explained by behavioural and life history advantages that correlate with anubis ancestry.

Allele-specific gene expression in a wild nonhuman primate population

Natural populations hold enormous potential for evolutionary genetic studies, especially when phenotypic, genetic and environmental data are all available on the same individuals. However, untangling the genotype-phenotype relationship in natural populations remains a major challenge. Here, we describe results of an investigation of one class of phenotype, allele-specific gene expression (ASGE), in the well-studied natural population of baboons of the Amboseli basin, Kenya. ASGE measurements identify cases in which one allele of a gene is overexpressed relative to the alternative allele of the same gene, within individuals, thus providing a control for background genetic and environmental effects. Here, we characterize the incidence of ASGE in the Amboseli baboon population, focusing on the genetic and environmental contributions to ASGE in a set of eleven genes involved in immunity and defence. Within this set, we identify evidence for common ASGE in four genes. We also present examples of two relationships between cis-regulatory genetic variants and the ASGE phenotype. Finally, we identify one case in which this relationship is influenced by a novel gene-environment interaction. Specifically, the dominance rank of an individual's mother during its early life (an aspect of that individual's social environment) influences the expression of the gene CCL5 via an interaction with cis-regulatory genetic variation. These results illustrate how environmental and ecological data can be integrated into evolutionary genetic studies of functional variation in natural populations. They also highlight the potential importance of early life environmental variation in shaping the genetic architecture of complex traits in wild mammals.

The pathogen recognition receptor NOD2 regulates human FOXP3+ T cell survival

The expression of pathogen recognition receptors in human FOXP3+ T regulatory cells is established, yet the function of these receptors is currently obscure. In the process of studying the function of both peripheral and lamina propria FOXP3+ lymphocytes in patients with the human inflammatory bowel disease Crohn's disease, we observed a clear deficiency in the quantity of FOXP3+ lymphocytes in patients with disease-associated polymorphisms in the pathogen recognition receptor gene NOD2. Subsequently, we determined that the NOD2 ligand, muramyl dipeptide (MDP), activates NF-kappaB in primary human FOXP3+ T cells. This activation is functionally relevant, as MDP-stimulated human FOXP3+ T cells are protected from death receptor Fas-mediated apoptosis. Importantly, apoptosis protection was not evident in MDP-stimulated FOXP3+ T cells isolated from a patient with the disease-associated polymorphism. Thus, we propose that one function of pathogen recognition receptors in human T regulatory cells is the protection against death receptor-mediated apoptosis in a Fas ligand-rich environment, such as that of the inflamed intestinal subepithelial space.

Genetic evidence reveals temporal change in hybridization patterns in a wild baboon population

The process and consequences of hybridization are of interest to evolutionary biologists because of the importance of hybridization in understanding reproductive isolation, speciation, and the influence of introgression on population genetic structure. Recent studies of hybridization have been enhanced by the advent of sensitive, genetic marker-based techniques for inferring the degree of admixture occurring within individuals. Here we present a genetic marker-based analysis of hybridization in a large-bodied, long-lived mammal over multiple generations. We analysed patterns of hybridization between yellow baboons (Papio cynocephalus) and anubis baboons (Papio anubis) in a well-studied natural population in Amboseli National Park, Kenya, using genetic samples from 450 individuals born over the last 36 years. We assigned genetic hybrid scores based on genotypes at 14 microsatellite loci using the clustering algorithm implemented in STRUCTURE 2.0, and assessed the robustness of these scores by comparison to pedigree information and through simulation. The genetic hybrid scores showed generally good agreement with previous morphological assessments of hybridity, but suggest that genetic methods may be more sensitive for identification of low levels of hybridity. The results of our analysis indicate that the proportion of hybrids in the Amboseli population has grown over time, but that the average proportion of anubis ancestry within hybrids is gradually decreasing. We argue that these patterns are probably a result of both selective and nonselective processes, including differences in the timing of life-history events for hybrid males relative to yellow baboon males, and stochasticity in long-distance dispersal from the source anubis population into Amboseli.

Age at maturity in wild baboons: genetic, environmental and demographic influences

The timing of early life-history events, such as sexual maturation and first reproduction, can greatly influence variation in individual fitness. In this study, we analysed possible sources of variation underlying different measures of age at social and physical maturation in wild baboons in the Amboseli basin, Kenya. The Amboseli baboons are a natural population primarily comprised of yellow baboons (Papio cynocephalus) that occasionally hybridize with anubis baboons (Papio anubis) from outside the basin. We found that males and females differed in the extent to which various factors influenced their maturation. Surprisingly, we found that male maturation was most strongly related to the proportion of anubis ancestry revealed by their microsatellite genotypes: hybrid males matured earlier than yellow males. In contrast, although hybrid females reached menarche slightly earlier than yellow females, maternal rank and the presence of maternal relatives had the largest effects on female maturation, followed by more modest effects of group size and rainfall. Our results indicate that a complex combination of demographic, genetic, environmental, and maternal effects contribute to variation in the timing of these life-history milestones.

A population-based study of the frequency of corticosteroid resistance and dependence in pediatric patients with Crohn's disease and ulcerative colitis

BACKGROUND

The goal of this study was to examine the 1-year outcome after the first course of systemic corticosteroids in an inception cohort of pediatric patients with inflammatory bowel disease.

METHODS

All Olmsted County (Minnesota) residents diagnosed with Crohn's disease (n = 50) or ulcerative colitis (n = 36) before 19 years of age from 1940 to 2001 were identified. Outcomes at 30 days and 1 year after the initial course of corticosteroids were recorded.

RESULTS

Twenty-six patients with Crohn's disease (65%) and 14 with ulcerative colitis (44%) were treated with corticosteroids before age 19. Thirty-day outcomes for corticosteroid-treated Crohn's disease were complete remission in 16 (62%), partial remission in 7 (27%), and no response in 3 (12%), with 2 of these patients requiring surgery. Thirty-day outcomes for treated ulcerative colitis were complete remission in 7 (50%), partial remission in 4 (29%), and no response in 3 (21%). One-year outcomes for Crohn's disease were prolonged response in 11 (42%) and corticosteroid dependence in 8 (31%), whereas 7 (27%) were postsurgical. One-year outcomes for ulcerative colitis were prolonged response in 8 (57%) and corticosteroid dependence in 2 (14%), whereas 4 (29%) were postsurgical.

CONCLUSIONS

Most pediatric patients with inflammatory bowel disease initially responded to corticosteroids. However, after 1 year, 58% of pediatric patients with Crohn's disease and 43% of pediatric patients with ulcerative colitis either were steroid dependent or required surgery. This finding emphasizes the need for early steroid-sparing medications in pediatric inflammatory bowel disease.

Bone marrow failure in children with acute liver failure

BACKGROUND

Aplastic anemia is a rare but well-recognized complication of acute hepatitis and acute liver failure. The cause is unknown, and the condition is fatal without bone marrow recovery. Treatment includes immunosuppression regimens or bone marrow transplantation. The purpose of this study was to investigate the incidence, cause, treatment, and outcomes of this disorder in children.

METHODS

Retrospective chart review of 75 patients with acute liver failure in a major pediatric liver center.

RESULTS

Eight patients had evidence of bone marrow failure. Of those, six had aplastic anemia, and two had transient bone marrow suppression. There were five boys, median age 57 months (range, 36-132 months). Two had parvovirus B19, six had non-A, non-B, non-C hepatitis. Five underwent liver transplantation: auxiliary in one, orthotopic in four. The interval between initial symptoms and development of aplastic anemia and/or bone marrow suppression was 21 to 99 days (median, 39 days). Four patients with aplastic anemia received intravenous antithymocyte globulin (ATG) or antilymphocyte globulin (ALG). Median recovery period of granulopoiesis was 62 days (range, 27-115 days). Two made a full recovery, one had myelodysplasia, and one with unresponsive disease died of septic complications. Four did not receive ATG/ALG, two had aplastic anemia, and two had bone marrow suppression. Three underwent liver transplantation, and all four resumed granulopoiesis. One child who underwent liver transplantation died of sepsis with chronic rejection. Median recovery of granulopoiesis was 99 days (range, 20-153 days).

CONCLUSIONS

Bone marrow failure occurs in 10.7% of children with acute liver failure. It sometimes occurs in association with non-A, non-B, non-C hepatitis and parvovirus B19 infection. Treatment with ATG/ALG is successful and is well tolerated in most cases.

Prognosis of alpha-1-antitrypsin deficiency-related liver disease in the era of paediatric liver transplantation

BACKGROUND/AIM

Alpha-1-antitrypsin deficiency (alpha1ATD) is the commonest metabolic disease leading to liver transplantation (LT) in children. Approximately 10-15% of the PiZZ population develops liver disease. Five percent of them will require LT within the first 4 years of life. This study aimed to investigate the prognosis of the liver disease associated with PiZZ alpha1ATD in the era of liver transplantation and to determine predictors of outcome.

METHODS

We reviewed retrospectively the clinical notes of 97 consecutive patients referred from January 1989, when LT became routinely available in our Unit, to July 1998.

RESULTS

Of 26 (27%) patients who developed end-stage liver disease, 24 have been transplanted and two are waiting for LT. Twenty-one (81%) of these patients presented with neonatal hepatitis at a median age of 2.1 months. Of 71 (73%) children who have not required LT, 61 (86%) presented with neonatal hepatitis at a median age of 1.6 months. Among infants with neonatal hepatitis who required LT, 18 out of 21 (86%) had jaundice for more than 6 weeks compared with 34 of 61 (56%) who survived without LT (p<0.01). Children requiring LT had higher aspartate aminotransferase (AST) at presentation (p<0.0001) and both higher AST and gamma-glutamyl transferase (GGT) at 6 months (p<0.001), 1-year (p<0.0003) and 5-year (p<0.01) follow up when compared to those who are well without LT. Furthermore, children who developed end-stage liver disease more frequently had severe bile duct reduplication (p<0.01), severe fibrosis (p<0.03) with bridging septa (p<0.02) and established cirrhosis (p<0.04) in the initial liver biopsy. Ninety-five of the 97 children (98%) are currently alive; two died after LT.

CONCLUSIONS

The advent of liver transplantation has significantly improved the prognosis of liver disease associated with PiZZ alpha1ATD. Duration of jaundice, severity of histological features and biochemical abnormalities predict outcome at an early stage of the disease.

Cutting edge: a role for CD1 in the pathogenesis of lupus in NZB/NZW mice

Since anti-CD1 TCR transgenic T cells can activate syngeneic B cells via CD1 to secrete IgM and IgG and induce lupus in BALB/c mice, we studied the role of CD1 in the pathogenesis of lupus in NZB/NZW mice. Approximately 20% of B cells from the spleens of NZB/NZW mice expressed high levels of CD1 (CD1high B cells). The latter subset spontaneously produced large amounts of IgM anti-dsDNA Abs in vitro that was up to 25-fold higher than that of residual CD1int/low B cells. T cells in the NZB/NZW spleen proliferated vigorously to the CD1-transfected A20 B cell line, but not to the parent line. Treatment of NZB/NZW mice with anti-CD1 mAbs ameliorated the development of lupus. These results suggest that the CD1high B cells and their progeny are a major source of autoantibody production, and activation of B cells via CD1 may play an important role in the pathogenesis of lupus.

Purification and cloning of amyloid precursor protein beta-secretase from human brain

Proteolytic processing of the amyloid precursor protein (APP) generates amyloid beta (Abeta) peptide, which is thought to be causal for the pathology and subsequent cognitive decline in Alzheimer's disease. Cleavage by beta-secretase at the amino terminus of the Abeta peptide sequence, between residues 671 and 672 of APP, leads to the generation and extracellular release of beta-cleaved soluble APP, and a corresponding cell-associated carboxy-terminal fragment. Cleavage of the C-terminal fragment by gamma-secretase(s) leads to the formation of Abeta. The pathogenic mutation K670M671-->N670L671 at the beta-secretase cleavage site in APP, which was discovered in a Swedish family with familial Alzheimer's disease, leads to increased beta-secretase cleavage of the mutant substrate. Here we describe a membrane-bound enzyme activity that cleaves full-length APP at the beta-secretase cleavage site, and find it to be the predominant beta-cleavage activity in human brain. We have purified this enzyme activity to homogeneity from human brain using a new substrate analogue inhibitor of the enzyme activity, and show that the purified enzyme has all the properties predicted for beta-secretase. Cloning and expression of the enzyme reveals that human brain beta-secretase is a new membrane-bound aspartic proteinase.