Pediatric Biopsies Research Articles

IDENTIFYING CANCER SPECIFIC METABOLIC SIGNATURES USING CONSTRAINT-BASED MODELS.

Cancer metabolism differs remarkably from the metabolism of healthy surrounding tissues, and it is extremely heterogeneous across cancer types. While these metabolic differences provide promising avenues for cancer treatments, much work remains to be done in understanding how metabolism is rewired in malignant tissues. To that end, constraint-based models provide a powerful computational tool for the study of metabolism at the genome scale. To generate meaningful predictions, however, these generalized human models must first be tailored for specific cell or tissue sub-types. Here we first present two improved algorithms for (1) the generation of these context-specific metabolic models based on omics data, and (2) Monte-Carlo sampling of the metabolic model ux space. By applying these methods to generate and analyze context-specific metabolic models of diverse solid cancer cell line data, and primary leukemia pediatric patient biopsies, we demonstrate how the methodology presented in this study can generate insights into the rewiring differences across solid tumors and blood cancers.

A Strategy for Helicobacter Immunohistochemistry Utilization in Pediatric Practice: Insights From Morphologic and Cost-Benefit Analyses.

Recent studies in adults have examined the utility of immunohistochemistry (IHC) in detecting Helicobacter in gastric biopsy specimens and reached differing conclusions. Dedicated cost-benefit analysis of Helicobacter IHC in pediatric gastric biopsy specimens has not been performed. From 1,955 pediatric gastric biopsies in a 1-year period, we identified 63 Helicobacter -positive and 120 Helicobacter -negative biopsy specimens. All cases were scored according to the Updated Sydney System for the severity of inflammation. We observed that pediatric Helicobacter infection was significantly associated with germinal center formation, active inflammation, oxyntic mucosa with moderate to severe chronic inflammation, and antral mucosa with any chronic inflammation, exclusive of mild and superficial chronic inflammation. At least one associated pattern was seen in each Helicobacter -positive biopsy specimen. In comparison with adults, pediatric Helicobacter -positive biopsy specimens are more likely to lack acute inflammation and more likely to show moderate to marked chronic inflammation. We recommend performing Helicobacter IHC on pediatric gastric biopsy specimens with any of the above inflammatory patterns. This approach can sensitively identify pediatric patients with Helicobacter gastritis, limit IHC staining to approximately 30% of all gastric biopsy specimens, and reduce costs by up to $55,306.90 per 1,000 biopsy specimens.

Intraductal Fenestration of Biliary Metal Stents Using Argon Plasma to Facilitate Bilateral Hilar Stenting

Background: When placed across the biliary confluence, uncovered self-expanding metal stents (SEMS) may impede access to the contralateral intrahepatic ducts. In particular it is difficult to place additional plastic or metal stents across multiple adjacent cells of a hilar SEMS. Argon plasma has been used to trim biliary SEMS. However, the use of argon plasma for intraductal fenestration of biliary metal stents has not been described. Case report: A 38-year-old man with hilar cholanogiocarcinoma presented with cholangitis and right lobe liver abscesses. He had been previously treated with placement of multiple closed-cell, uncovered SEMS extending from duodenum to left hepatic duct. A percutaneous transhepatic catheter was placed into an abscess cavity, which communicated with right hepatic ducts. Subsequently a percutaneous transhepatic guidewire was advanced through the hilar SEMS interstices and into the duodenum. During ERCP a temporary plastic stent was placed into the left main duct for venting of argon gas. The percutaneous guidewire was then grasped with a snare and brought out via the mouth. Choledochoscopy was then performed using a pediatric gastroscope which was advanced over the guidewire into the existing SEMS up to the level of the hilum. Metal struts of the embedded SEMS were seen crisscrossing over the right duct orifice. The visible SEMS wires were fenestrated using a pediatric argon plasma coagulation probe at power of 80 W and flow 0.3 L/min, and further unwoven with a pediatric biopsy forceps. Argon gas vented from the percutaneous biliary sheath as well as the left hepatic duct stent. Subsequently plastic stents were placed via a duodenoscope into 4 separate right intrahepatic ducts, each of which was accessed across adjacent interstices of the SEMS. The patient had rapid clinical improvement and a follow-up computed tomography at 4 weeks showed resolution of liver abscesses. Conclusion: Fenestration of hilar biliary SEMS using argon plasma under direct endoscopic visualization can facilitate bilateral hilar stent placement in patients with complex malignant obstruction of the central intrahepatic ducts. Argon plasma has been used to trim biliary and rectal SEMS. The use of argon plasma for endoscopic fenestration of duodenal stents to facilitate ERCP has also been reported. Our case extends the application of this technique by describing intraductal fenestration of an indwelling biliary SEMS to accomplish bilateral hilar stenting.

Hemorrhoidal Energy Treatment: A Single-Center Retrospective Analysis of a Novel Technique for Treating Internal Hemorrhoids

Introduction: Internal hemorrhoids are a common cause of rectal bleeding. Traditional first line therapy for Grade I & II bleeding internal hemorrhoids has been conservative management. Various non-surgical and surgical treatment modalities are available for bleeding hemorrhoids. A novel, non-surgical, bipolar electrotherapy probe, the Hemorrhoid Energy Treatment (HET) System, has shown efficacy in the management of bleeding Grade I & II hemorrhoids. Methods: The study included 42 adults with Grade I or II internal hemorrhoids and rectal bleeding who underwent HET from March 2015 to March 2016. Each patient had at least 3-month post treatment follow up. Our retrospective chart review study was IRB approved. 38 subjects out of 42 responded to a telephonic follow-up questionnaire. The questionnaire inquired about post-HET pain, complete resolution of bleeding, improvement in bleeding, and use of stool softeners post-HET. Descriptive analysis was performed. Results: The cohort included 15 males and 23 females, with a mean age of 50±14.8 years. Patients reported average symptom duration of 10.8±10 months, prior to treatment. 36 patients underwent HET under moderate sedation, 1 under general anesthesia, and 1 without any sedation. In 29 patients (76%), HET was performed during flexible sigmoidoscopy; in 9 patients (24%) HET was performed during colonoscopy. The mean procedure time was 13.7±6.1 minutes. Our “modified” HET technique (use of pediatric biopsy forceps and gastroscope assistance) was utilized in 5 subjects and our “standard” HET technique (use of HET and gastroscope guidance only) was used in 33 subjects. None of the patients reported pain or rectal discomfort during the procedure. 33 patients (87%) reported no pain post procedure (Fig 1). 28 patients (74%) reported complete resolution of rectal bleeding (Fig 2). 10 patients reported continued bleeding with 8/10 patients from this group reporting improvement in bleeding post HET treatment. 2 patients (5%) reported no improvement in bleeding symptoms. 19 patients (50%) were able to discontinue stool softener use (Table 1).Figure 1Figure 2Table 1: Responses to Telephonic QuestionnaireConclusion: HET enabled complete resolution of hemorrhoidal bleeding in the majority (74%) of our patient cohort. In addition, most patients reported post-procedure improvement in bleeding. HET is a well-tolerated, safe and effective outpatient procedure for treating rectal bleeding due to hemorrhoids. Our study represents the largest reported HET experience to date.

Laser acupuncture reduces pain in pediatric kidney biopsies: a randomized controlled trial.

Evaluate laser acupuncture (LA) as an adjuvant therapy in pain management during percutaneous kidney biopsy procedure in children and adolescents. This prospective, double-blinded, randomized controlled trial enrolled patients aged 7 to 26 years admitted to a children's hospital for percutaneous kidney biopsy. Patients received LA to treatment points (acupuncture group) or sham points (control group) before the procedure. The laser delivered a dose of 42 J/cm over 10 acupoints. Patients and parents rated the pain during and after the biopsy, and change in pain scores were calculated for each patient. Anxiety, vital signs, sedation medication, and patient's biopsy experience were secondary outcomes. Sixty-nine treatments (33 in the acupuncture group and 36 in the control group) were eligible for analysis. Patients in the acupuncture group reported a significantly improved change in the pain score after the biopsy compared with the controls (0.8 vs -0.5, P = 0.044). Patients in the acupuncture group had a statistically significant decrease in procedure vital signs including heart rate (-1.8 vs 5.6, P = 0.043) and respiratory rate (-2.4 vs 0.4, P = 0.045) when compared with controls. Parents also perceived a correspondingly greater improvement in their child's pain for those in the acupuncture group compared with the controls (2.3 vs 0.3, P = 0.04). Adjunctive LA significantly improved pain after pediatric percutaneous kidney biopsies.

P.404 - Muscle fibre size revisited: Updated age-stratified normative data in histologically normal/minimal change (HN/MC) paediatric quadriceps biopsies using a high-throughput automated digital script

P.404 - Muscle fibre size revisited: Updated age-stratified normative data in histologically normal/minimal change (HN/MC) paediatric quadriceps biopsies using a high-throughput automated digital script

Importance of the Evaluation of N-Acetyltransferase Enzyme Activity Prior to 5-Aminosalicylic Acid Medication for Ulcerative Colitis.

5-aminosalicylic acid (5-ASA) is a classic anti-inflammatory drug for the treatment of ulcerative colitis. N-acetyltransferase (NAT) enzymes convert 5-ASA to its metabolite N-acetyl-5-ASA, and it is unresolved whether 5-ASA or N-acetyl-5-ASA is the effective therapeutic molecule. We previously demonstrated that colonic production of N-acetyl-5-ASA (NAT activity) is decreased in dextran sulfate sodium-induced colitis. Our hypothesis is that 5-ASA is the therapeutic molecule to improve colitis, with the corollary that altered NAT activity affects drug efficacy. Since varying clinical effectiveness of 5-ASA has been reported, we also ask if NAT activity varies with inflammation in pediatric or adult patients. Acute colonic inflammation was induced in C57BL/6 NAT wild-type (WT) or knockout mice, using 3.5% dextran sulfate sodium (w/v) concurrent with 5-ASA treatment. Adult and pediatric rectosigmoid biopsies were collected from control or patients with ulcerative colitis. Tissue was analyzed for NAT and myeloperoxidase activity. Dextran sulfate sodium-induced colitis was of similar severity in both NAT WT and knockout mice, and NAT activity was significantly decreased in NAT WT mice. In the setting of colitis, 5-ASA significantly restored colon length and decreased myeloperoxidase activity in NAT knockout but not in WT mice. Myeloperoxidase activity negatively correlated with NAT activity in pediatric patients, but correlation was not observed in adult patients. Inflammation decreases NAT activity in the colon of mice and human pediatric patients. Decreased NAT activity enhances the therapeutic effect of 5-ASA in mice. A NAT activity assay could be useful to help predict the efficacy of 5-ASA therapy.

Proteomic analysis of ascending colon biopsies from a paediatric inflammatory bowel disease inception cohort identifies protein biomarkers that differentiate Crohn's disease from UC

ObjectiveAccurate differentiation between Crohn's disease (CD) and UC is important to ensure early and appropriate therapeutic intervention. We sought to identify proteins that enable differentiation between CD and UC in...

Assessing DNA methylation in the developing human intestinal epithelium: potential link to inflammatory bowel disease.

DNA methylation is one of the major epigenetic mechanisms implicated in regulating cellular development and cell-type-specific gene expression. Here we performed simultaneous genome-wide DNA methylation and gene expression analysis on purified intestinal epithelial cells derived from human fetal gut, healthy pediatric biopsies, and children newly diagnosed with inflammatory bowel disease (IBD). Results were validated using pyrosequencing, real-time PCR, and immunostaining. The functional impact of DNA methylation changes on gene expression was assessed by employing in-vitro assays in intestinal cell lines. DNA methylation analyses allowed identification of 214 genes for which expression is regulated via DNA methylation, i.e. regulatory differentially methylated regions (rDMRs). Pathway and functional analysis of rDMRs suggested a critical role for DNA methylation in regulating gene expression and functional development of the human intestinal epithelium. Moreover, analysis performed on intestinal epithelium of children newly diagnosed with IBD revealed alterations in DNA methylation within genomic loci, which were found to overlap significantly with those undergoing methylation changes during intestinal development. Our study provides novel insights into the physiological role of DNA methylation in regulating functional maturation of the human intestinal epithelium. Moreover, we provide data linking developmentally acquired alterations in the DNA methylation profile to changes seen in pediatric IBD.

205 Decreasing pediatric skin biopsy rates of lesions that were pigmented in a large health system

205 Decreasing pediatric skin biopsy rates of lesions that were pigmented in a large health system

Significance of Paneth Cells in Histologically Unremarkable Rectal Mucosa.

Paneth cell metaplasia of the rectal epithelium is a common histologic finding in patients with chronic inflammatory bowel disease. However, the clinical significance of isolated Paneth cells in otherwise unremarkable rectal mucosa has not been extensively examined. This study examined the frequency and clinical correlates of rectal Paneth cells in 245 biopsies obtained from patients between the ages of 2 weeks to 20 years in a pediatric tertiary care facility from 2010 to 2011. The specimens comprised 193 endoscopic pinch biopsies and 52 rectal suction biopsies. All 245 cases were endoscopically and histologically unremarkable with no prominence of eosinophils, no altered mucosal architecture, and no inflammation. Paneth cells were present in 42 cases (17.1%), which is higher than previous reports. Only 1 of 42 patients with rectal Paneth cells was subsequently diagnosed with Crohn disease. In our study population, the finding of Paneth cells was associated with young age, and the incidence of Paneth cell cases decreased with increasing age (χ=13.69, P=0.0002). Constipation was the most common presenting symptom in patients with rectal Paneth cells and was highly associated with the presence of Paneth cells (odds ratio 4.5, 95% confidence interval: 2.2-9.0). Paneth cells in otherwise unremarkable pediatric rectal biopsies are not rare and frequently occur in common conditions such as idiopathic constipation.

Positive trends in paediatric renal biopsy service provision in the UK: a national survey and re-audit of paediatric renal biopsy practice.

Paediatric renal biopsy standards introduced in the UK in 2010 were intended to reduce variation and improve practice. A concurrent national drive was aimed at building robust paediatric nephrology networks to ensure services cater for the needs of the family and minimise time away from home. We aimed to identify current national practice since these changes on behalf of the British Association for Paediatric Nephrology. All UK paediatric nephrology centres were invited to complete a survey of their biopsy practice, including advance preparation. From 1 January to 30 June 2012, a national prospective audit of renal biopsies was undertaken at participating centres comparing practice with the British Association for Paediatric Nephrology (BAPN) standards and audit results from 2005. Survey results from 11 centres demonstrated increased use of pre-procedure information leaflets (63.6% vs 45.5%, P = 0.39) and play preparation (90.9% vs 9.1%, P = 0.0001). Audit of 331 biopsies showed a move towards day-case procedures (49.5% vs 32.9%, P = 0.17) and reduced major complications (4.5% vs 10.4%, P = 0.002). Biopsies with 18-gauge needles had significantly higher mean pass rates (3.2 vs 2.3, P = 0.0008) and major complications (15.3% vs 3.3%, P = 0.0015) compared with 16-gauge needles. Percutaneous renal biopsy remains a safe procedure in children, thus improving family-centered service provision in the UK.

Performing CLOtest on all Pediatric Gastric Biopsies: Does It Add Diagnostic Value?

Helicobacter pylori (HP) was discovered by culture from gastric biopsies in 1982 by Drs. Marshall and Warren. Since then, urease tests have been developed for rapid diagnosis of HP infection. Our goal was to determine whether performing a urease test—CLOtest (Kimberly Clark)—on all gastric biopsies upfront has diagnostic value. All gastric biopsies performed between January 1 …

MMPs‐2 and ‐14 Are Elevated in Eosinophilic Esophagitis and Reduced Following Topical Corticosteroid Therapy

Eosinophilic esophagitis (EoE) is a chronic, antigen-mediated disease in children and adults associated with substantial esophageal remodeling and fibrosis. The expression of the remodeling-associated matrix metalloproteinases (MMPs) has not been previously detailed in EoE. MMP-2 and -14 expression and cellular localization were assessed using real-time quantitative polymerase chain reaction and immunohistochemistry/immunofluorescence in EoE fibroblasts, active and inactive pediatric EoE biopsies, and nondiseased control biopsies. The effect of transforming growth factor (TGF)-β1 treatment on MMP-2 expression in cultured esophageal epithelial (HET1A) cells was analyzed. MMP-2 and -14 mRNA were expressed in EoE fibroblasts and biopsies. Proliferating epithelial cells produced MMP-14 more abundantly in EoE than in controls (P < 0.001) and the degree of epithelial MMP-14 expression correlated positively with basal zone hyperplasia (r = 0.65, P = 0.002). EoE lamina propria had higher numbers of MMP-2- and -14-positive cells (906 ± 167 and 701 ± 93 cells/mm²) as compared with controls (258 ± 93 cells/mm², P < 0.01 and 232 ± 54 cells/mm², P < 0.01), and MMP-14 expression correlated with the severity of fibrosis. Following therapy with topical corticosteroids, MMP-14 and -2 were significantly diminished (P < 0.01). TGF-β1 increased the expression and secretion of MMP-2 from esophageal epithelial HET1A cells. MMP-2 and -14 are elevated in pediatric patients with EoE and significantly decrease following topical corticosteroid therapy. TGF-β1 increases MMP-2 in esophageal epithelial cells. This alludes to previously unappreciated role for MMPs in EoE-associated esophageal remodeling and a potential positive feedback loop via TGF-β1.

Predictors of diagnostic success in image-guided pediatric soft-tissue biopsies.

Image-guided percutaneous core needle biopsy (PCNB) of soft-tissue lesions is a minimally invasive technique that can provide a definitive diagnosis for treatment. Anatomical and age considerations in children require judicious use of safe percutaneous biopsy techniques. There are, however, limited data on the determinants of diagnostic yield in soft-tissue lesions in this population. To assess lesion-related and technical factors that affect diagnostic yield and safety in PCNB of pediatric soft-tissue lesions. This was a retrospective cohort study of 205 PCNB performed from January 2000 to July 2014. Diagnostic yield and its associations with technical and lesion-related factors were evaluated using bivariate analysis. The mean patient age was 11.1 ± 6.9years (interquartile range [IQR]: 4.3-16years). Ultrasound guidance alone was used in 91% of cases. The mean number of passes was 7.5 ± 3.2 (IQR: 5-9 passes) per case. The overall diagnostic yield was 75% and the overall accuracy was 88%. Performing fewer than four passes was associated with a nondiagnostic biopsy (P = 0.001). There were no lesion or other technical factors that predicted a diagnostic biopsy. There were two complications (1%) over 14years. Image-guided PCNB is a safe and effective means for the diagnosis of pediatric soft-tissue abnormalities. Aside from performing at least four passes, our data show no technical or lesion-related factors that increase diagnostic yield in pediatric PCNB of soft-tissue lesions.

Su1583 Pediatric Biopsy Forceps vs Spybite Forceps Comparison At the Diagnosis of Biliary Strictures: a Randomized Study

Su1583 Pediatric Biopsy Forceps vs Spybite Forceps Comparison At the Diagnosis of Biliary Strictures: a Randomized Study

Pediatric nerve biopsy in tertiary referral frequently assists in diagnosis and therapeutic management (P2.001)

Pediatric nerve biopsy in tertiary referral frequently assists in diagnosis and therapeutic management (P2.001)

High-Throughput Screening of Human Leukemia Xenografts to Identify Dexamethasone Sensitizers

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Glucocorticoids (e.g., dexamethasone) form a critical component of chemotherapy regimens for pediatric ALL, and the initial response to glucocorticoid therapy is a major prognostic factor, where resistance is predictive of poor outcome. We have previously established a clinically relevant ALL xenograft model, consisting of primary pediatric ALL biopsies engrafted into immune-deficient mice, in which in vitro and in vivo dexamethasone sensitivity significantly correlated with patient outcome. In this study, we used high-throughput screening (HTS) to identify novel compounds that reverse dexamethasone resistance in a xenograft (ALL-19) derived from a chemoresistant pediatric ALL patient that is representative of the most common pediatric ALL subtype (B-cell precursor [BCP-ALL]). The compound 2-(4-chlorophenoxy)-2-methyl-N-(2-(piperidin-1-yl)phenyl)propanamide showed little cytotoxic activity alone (IC50 = 31 µM), but when combined with dexamethasone, it caused a marked decrease in cell viability. Fixed-ratio combination assays were performed against a broad panel of dexamethasone-resistant and -sensitive xenografts representative of BCP-ALL, T-cell ALL, and Mixed Lineage Leukemia–rearranged ALL, and synergy was observed in six of seven xenografts. We describe here the development of a novel 384-well cell-based high-throughput screening assay for identifying potential dexamethasone sensitizers using a clinically relevant ALL xenograft model.

Usefulness of Trans-Nasal Ultra-Thin Office Endoscopy in High-Risk Pre-Bariatric Patients

Introduction: Esophagogastroduodenoscopy (EGD) is an important tool for evaluating pre-bariatric patients. Obese patients are at high risk for airway complications during conventional sedated endoscopy. It is well known that sedation in obese patients is challenging due to the risks of sleep apnea and airway compromise while performing esophageal intubation. Improvement in technology has led to the use of ultra-thin scopes that can be used trans-nasally with minimal risk, patient discomfort, safety and efficacy. Methods: Thirty-one patients with pre-bariatric screening indications. The variables assessed were the success rate, tolerability and reliability with no use of sedation in the office setting. The endoscope used for all the procedures was the GIF-N180 Olympus 4.9 mm gastroscope. Biopsies were procured with a 2 mm pediatric biopsy forceps. Two percent lidocaine gel was applied to the nasal orifice prior to the procedure. Results: The study looked at 31 patients from June 2011 to June 2014 ( 14 men and 17 women) with an average age of 32 years ( ranging from 21 to 46) and a BMI range of 35 to 55. All 31 patients had successful intubation of the second duodenal portion with no safety concerns or complications. Common pathology was found in all the patients with gastritis (100%), esophagitis (83%), esophageal reflux (50%), hiatial hernia (33%) and gastric ulcer (16%). All of the patients were satisfactorily assessed and cleared for bariatric surgery.After appropriate therapy the pathology specimens were adequately analyzed and satisfactorily in all the patients. Conclusion: Initial data suggests that unsedated ultra-thin endoscopy with 4.9 mm diameter GIFN180 scope is safely feasible in ambulatory office care setting with the majority of pre-bariatric patients tolerating the procedure with no sedation. Alami et al. have done previous studies where they looked at morbidly obese patients in the out patient hospital setting. They showed all 25 patients reported successful endoscopy with no sedation using a 5.9 mm diameter GIF XP 160. Our study was able to show similar efficacy and safety in the ambulatory physician office setting with an even smaller(4.9 mm) scope. In the era of affordable and accountable care, this may prove to be the most effective and appropriate approach in Pre-Bariatric endoscopic screening and assessment of such patients.

Pediatric reference Raman data for material characteristics of iliac trabecular bone

Bone material characteristics are important contributors in the determination of bone strength. Raman spectroscopic analysis provides information on mineral/matrix ratio, mineral maturity/crystallinity, relative pyridinoline (Pyd) collagen cross-link content, relative proteoglycan content and relative lipid content. However, published reference data are available only for adults. The purpose of the present study was to establish reference data of Raman outcomes pertaining to bone quality in trabecular bone for children and young adults. To this end, tissue age defined Raman microspectroscopic analysis was performed on bone samples from 54 individuals between 1.5 and 23years with no metabolic bone disease, which have been previously used to establish histomorphometric and bone mineralization density distribution reference values. Four distinct tissue ages, three well defined by the fluorescent double labels representing early stages of bone formation and tissue maturation (days 3, 12, 20 of tissue mineralization) and a fourth representing old mature tissue at the geometrical center of the trabeculae, were analyzed. In general, significant dependencies of the measured parameters on tissue age were found, while at any given tissue age, sex and subject age were not confounders. Specifically, mineral/matrix ratio, mineral maturity/crystallinity index and relative pyridinoline collagen cross-link content index increased by 485%, 20% and 14%, respectively between days 3 and 20. The relative proteoglycan content index was unchanged between days 3 and 20 but was elevated in the old tissue compared to young tissue by 121%. The relative lipid content decreased within days 3 to 20 by −22%. Thus, the method allows not only the monitoring of material characteristics at a specific tissue age but also the kinetics of tissue maturation as well. The established reference Raman database will serve as sensitive tool to diagnose disturbances in material characteristics of pediatric bone biopsy samples.