Impact of villitis of unknown etiology and adverse acute neonatal outcomes in Eastern Ontario.

Introduction: Villitis of unknown etiology (VUE) is a histopathological lesion associated with adverse neonatal outcomes. We seek to define the obscure relationship between the severity and distribution of VUE and adverse neonatal outcomes.

Methods: A retrospective chart review was conducted of pathologic findings from singleton placentas diagnosed with VUE between 2013 and 2019.

Establishing normal ranges for fetal and neonatal small and large intestinal lengths: results from a prospective postmortem study.

Objective: To establish reference intervals (RIs) for fetal and neonatal small and large intestinal lengths.

Methods: Linear measurements on small and large intestines were made upon postmortem examination of 131 preterm and term infants with gestational ages between 13 and 41 weeks. All cases were referred from the Eastern Ontario and Western Québec regions to a tertiary care hospital.

Peri-Operative Liver Fibrosis and Native Liver Survival in Pediatric Patients with Biliary Atresia: A Systematic Review and Meta-Analysis.

No systematic review to date has examined histopathological parameters in relation to native liver survival in children who undergo the Kasai operation for biliary atresia (BA). A systematic review and meta-analysis is presented, comparing the frequency of native liver survival in peri-operative severe vs. non-severe liver fibrosis cases, in addition to other reported histopathology parameters.

Diverticular disease in a pediatric patient with Crohn's disease mimicking a perforated post-appendectomy appendiceal stump.

We present the finding of a diverticulum in the colonic wall of the cecum, arising in the context of ileocecal stricture in a child with Crohn disease mimicking a post-appendectomy perforated appendiceal stump. To our knowledge, a non-Meckel diverticulum in a pediatric patient with Crohn disease has not yet been reported and we examine the mechanics behind it. According to the Laplace Law, the pressure inside a container with curved walls is inversely proportional to its radius.

Evaluating the Prognostic Implication of the Collins Histology Scoring System in a Pediatric Eastern Ontario Population With Eosinophilic Esophagitis.

Introduction: Collins et al developed a histology scoring system (EoE HSS) to assess multiple pathologic features. The aim of this study is to identify if the EoE HSS can better detect endoscopic and symptom improvement vs the Peak Eosinophilic Count (PEC).

Methods: A retrospective chart review was performed for patients during 2014-2016.

Associations between Cellular Energy and Pediatric Inflammatory Bowel Disease Patient Response to Treatment.

Inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis, are chronic diseases of the gastrointestinal tract, with an unknown etiology, that affect over 6.8 million people worldwide. To characterize disease pathogenesis, proteomic and bioinformatic analyses were performed on colon biopsies collected during diagnostic endoscopy from 119 treatment-naïve pediatric patients, including from 78 IBD patients and 41 non-IBD patients who served as controls.

Homozygous WNT9B variants in two families with bilateral renal agenesis/hypoplasia/dysplasia.

WNT9B plays a key role in the development of the mammalian urogenital system. It is essential for the induction of mesonephric and metanephric tubules, the regulation of renal tubule morphogenesis, and the regulation of renal progenitor cell expansion and differentiation. To our knowledge, WNT9B has not been associated with renal defects in humans; however, WNT9B mice have renal agenesis/hypoplasia and reproductive tract abnormalities.

Impact of SARS-CoV-2 on the clinical outcomes and placental pathology of pregnant women and their infants: A systematic review.

Pregnant women are susceptible to viral infections due to physiological changes such as cell-mediated immunity. No severe adverse pregnancy or neonatal outcomes have been consistently reported in 2019 novel coronavirus disease (COVID-19) positive pregnancy cases. There are controversies around the role of COVID-19 in pregnancy.

Risk of Lower Birth Weight and Shorter Gestation in Oocyte Donation Pregnancies Compared With Other Assisted Reproductive Technology Methods: Systematic Review.

Objective: Oocyte donation (OD) is associated with an increased risk of pregnancy-induced hypertension, but the evidence of an association between OD and infant outcomes, including birth weight and gestational age, is conflicting. This study sought to determine the associations between oocyte donation and birth weight or gestational age compared with other forms of autologous oocyte assisted reproductive technology (ART).

Methods: Medline, Embase, and the CENTRAL Trials Registry of the Cochrane Collaboration were searched using a comprehensive search strategy.

Sclerosing Pneumocytoma of the Lungs Arising in a Child With PTEN Mutation.

We report a rare case of sclerosing pneumocytoma occurring in a child with PTEN mutation. A 13-year-old female presented to the emergency department of an adult hospital following 2 to 3 days of upper respiratory tract infection symptoms. A primary lung lesion was discovered during her initial chest X-ray to rule out pneumonia.

Dermal non-neural granular cell tumor in a 3-year-old child.

Dermal non-neural granular cell tumors, also known as primitive polypoid granular cell tumors, are a rare group of distinct cutaneous non-neural granular cell tumors. Pediatric cases are rare, and to the best of our knowledge, we report the youngest patient with dermal non-neural granular cell tumors.

Pediatric Blastic Plasmacytoid Dendritic Cell Neoplasm: A Systematic Literature Review.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare aggressive hematologic malignancy characterized by frequent skin involvement that most commonly affects older patients. BPDCN is known to have a poor prognosis. Our objective was to assess if outcome and disease prognosis were independently influenced by age when evaluated with clinical presentation, sex, and treatment regimens.

Validation of an algorithm to identify children with biopsy-proven celiac disease from within health administrative data: An assessment of health services utilization patterns in Ontario, Canada.

Importance: Celiac disease (CD) is a common pediatric illness, and awareness of gluten-related disorders including CD is growing. Health administrative data represents a unique opportunity to conduct population-based surveillance of this chronic condition and assess the impact of caring for children with CD on the health system.

Objective: The objective of the study was to validate an algorithm based on health administrative data diagnostic codes to accurately identify children with biopsy-proven CD.

Value of upper endoscopic biopsies in predicting medical refractoriness in pediatric patients with ulcerative colitis.

Refractory ulcerative colitis (UC) occurs in patients who experience a severe disease manifestation that is unresponsive to medical therapy. The assessment of upper endoscopic microscopic findings and its correlation with refractory UC has not been fully studied in pediatric patients and is the focus of this study. Medical records of UC patients treated at a tertiary pediatric center between 2000 and 2014 were reviewed.

Review of Current Applications of Immunohistochemistry in Pediatric Nonneoplastic Gastrointestinal, Hepatobiliary, and Pancreatic Lesions.

Immunohistochemical (IHC) stains are widely used by pathologists for a variety of considerations in the diagnostic workup of pediatric nonneoplastic lesions in gastrointestinal (GI), hepatic, biliary, and pancreatic lesions. The pathologic changes cover a wide range and types of presentations, including inflammatory (bacterial and viral), metaplastic, posttransplant lymphoproliferative, autoimmune, metabolic, degenerative, developmental, and genetic conditions, among others. The everyday practical value of IHC stains covers primary identification, confirmation, differential, and/or exclusionary roles in the hands and eyes and minds of the practitioners.

Update on molecular findings in rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is the most common malignant soft tissue tumour in children and adolescents. Histologically RMS resembles developing fetal striated skeletal muscle. RMS is stratified into different histological subtypes which appear to influence management plans and patient outcome.

Value of histopathology for predicting the post-operative complications of ileo-anal anastomosis (J-pouch) procedure in children with refractory ulcerative colitis.

The J-pouch is a surgical procedure offered to children with refractory ulcerative colitis (UC) who have undergone subtotal colectomy to reconstruct a reservoir function with ileo-anal anastomosis. Unfortunately, post-operative complications may occur and can compromise the pouch function. We assessed rectal histopathology to determine whether severity of inflammation in the rectum prior to the creation of the J-Pouch was associated with post-operative complications.

Histologic analysis of eosinophils and mast cells of the gastrointestinal tract in healthy Canadian children.

Many gastrointestinal (GI) disorders, including GI eosinophilia and inflammatory bowel disease, can be characterized by increased mucosal eosinophils (EOs) or mast cells (MCs). Normal mucosal cellular counts along the GI tract in healthy children have not been established for a Canadian pediatric population. To establish a benchmark reference, we quantified EO and MC from 356 mucosal biopsies of the GI tract obtained during upper and lower endoscopic biopsies of 38 pediatric patients in eastern Ontario.

Congenital mesoblastic nephroma: a study of 19 cases using immunohistochemistry and ETV6-NTRK3 fusion gene rearrangement.

Mesoblastic nephroma (MN) is the most common renal tumour in the first 3 months of life and accounts for 3-5% of all paediatric renal neoplasms. To further understand the morphological variants of MN, we identified 19 cases of MN (five classic, eight cellular and six mixed) and examined each case for markers known to be important in urogenital embryological development (PAX8, WT1 and RCC), stem cell associated markers (Oct 4, CD34 and c-kit), muscle/myofibroblastic markers (muscle specific actin, calponin and h-caldesmon), aberrant transcription factors, cell cycle regulation and other oncogenic proteins (p16, cyclin D1 and beta-catenin). Fluorescence in situ hybridisation (FISH) testing for ETV6-NTRK3 gene fusion/rearrangement revealed further differentiation between the subtypes with ETV6-NTRK3 gene fusion detected in 0/5 of the classic MN, 8/8 of the cellular MN and 5/6 of the mixed MN cohorts, respectively.

Oocyte donation pregnancies and the risk of preeclampsia or gestational hypertension: a systematic review and metaanalysis.

The purpose of this study was to determine whether pregnancies that were achieved via oocyte donation, compared with pregnancies achieved via other assisted reproductive technology methods or natural conception, demonstrate increased risk of preeclampsia or gestational hypertension. Comparative studies of pregnancies that were achieved with oocyte donation vs other methods of assisted reproductive technology or natural conception with preeclampsia or gestational hypertension were included as 1 of the measured outcomes. Abstracts and unpublished studies were excluded.

The Placental Distal Villous Hypoplasia Pattern: Interobserver Agreement and Automated Fractal Dimension as an Objective Metric.

The distal villous hypoplasia (DVH) pattern is a placental correlate of fetal growth restriction. Because the pattern seems to involve less complexity than do appropriately developed placental villi, we postulated that it may be associated with lower fractal dimension-a mathematical measure of complexity. Our study objectives were to evaluate interobserver agreement related to the DVH pattern among expert pathologists and to determine whether pathologist classification of DVH correlates with fractal dimension.

Langerhans cell histiocytosis: a comprehensive review.

Langerhans cell histiocytosis (LCH) is currently regarded as a myeloid neoplasm, with remarkably broad clinical spectrum, ranging from isolated skin or bone lesions to a disseminated disease that can involve nearly any organ. LCH is generally regarded as a sporadic disease that occurs predominantly in the paediatric population. The diagnosis of LCH is confirmed by immunohistochemistry (IHC) by demonstrating the presence of dendritic cell markers such as S100 protein, in addition to CD1a and langerin.