Publications by authors named "Matthew J Hamilton"

Aims: Little is known about the molecular features of visible polyps with low-grade intestinal-type dysplasia in patients with inflammatory bowel disease (IBD). To better understand their origins and biological potential, we sought to genomically profile these lesions and compare them with invisible low-grade dysplasia and sporadic adenomas from non-IBD patients.

Methods: 22 polyps within areas of colitis, 13 polyps outside areas of colitis, 10 foci of invisible dysplasia from patients with IBD and 6 sporadic tubular adenomas from non-IBD patients were analysed using the OncoPanel assay.

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Mast cell activation syndrome (MCAS) is a term applied to several clinical entities that have gained increased attention from patients and medical providers. Although several descriptive publications about MCAS exist, there are many gaps in knowledge, resulting in confusion about this clinical syndrome. Whether MCAS is a primary syndrome or exists as a constellation of symptoms in the context of known inflammatory, allergic, or clonal disorders associated with systemic mast cell activation is not well understood.

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Purpose Of Review: Mast cell activation syndrome (MCAS) is a clinical disorder that may explain irritable bowel syndrome (IBS) type symptoms as well as other allergic symptoms experienced by an individual. The diagnosis and treatment of MCAS with specific focus on gastrointestinal (GI) manifestations is reviewed.

Recent Findings: Although biomarkers for MCAS remain elusive, testing for baseline serum tryptase will distinguish the type of mast cell disorder and urine tests for mast cell mediator metabolites may support the diagnosis.

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Introduction: The optimal proton pump inhibitor (PPI) regimen for eosinophilic esophagitis (EoE) is unclear. We compared histologic response rates of different dosing combinations.

Methods: A total of 305 patients with newly diagnosed EoE received standard (omeprazole 20 mg daily), once-daily moderate (40 mg daily), twice-daily moderate (20 mg twice daily), or high (40 mg twice daily) dose PPI for ≥8 weeks.

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Autonomic symptom questionnaires are frequently used to assess dysautonomia. It is unknown whether subjective dysautonomia obtained from autonomic questionnaires correlates with objective dysautonomia measured by quantitative autonomic testing. The objective of our study was to determine correlations between subjective and objective measures of dysautonomia.

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Fecal microbiota transplantation (FMT) has emerged as a highly effective therapy for recurrent infection (rCDI) and also a potential therapy for other diseases associated with dysbiotic gut microbiota. Monitoring metabolic changes in biofluids and excreta is a noninvasive approach to identify the biomarkers of microbial recolonization and to understand the metabolic influences of FMT on the host. In this study, the pre-FMT and post FMT urine samples from 11 rCDI patients were compared through metabolomic analyses for FMT-induced metabolic changes.

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Background: Growing evidence from dogs and humans supports the abundance of mutation-based biomarkers in tumors of dogs. Increasing the use of clinical genomic diagnostic testing now provides another powerful data source for biomarker discovery.

Hypothesis: Analyzed clinical outcomes in dogs with cancer profiled using SearchLight DNA, a cancer gene panel for dogs, to identify mutations with prognostic value.

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Gastrointestinal Disease in Mastocytosis.

Immunol Allergy Clin North Am

November 2023

Gastrointestinal symptoms are prevalent in patients with systemic mastocytosis and contribute to morbidity. In indolent disease, the symptoms, which include heartburn, abdominal pain, and diarrhea, are largely due to release of mast cell mediators but may be due to other factors. A thorough evaluation that incorporates abdominal imaging and endoscopy with intestinal biopsy assists with diagnosis and management.

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A subset of patients with eosinophilic esophagitis (EoE) respond to proton-pump inhibitor (PPI) therapy, however they cannot be distinguished prior to PPI trial and the mechanism of PPI response remains unclear. Improved understanding of the distinct patient phenotypes in PPI-responsive EoE (PPI-r-EoE), PPI-non-responsive EoE (PPI-nr-EoE) and erosive esophagitis (EE) may help guide management. The aim of this paper is to compare the clinical and allergy profiles of PPI-r-EoE versus PPI-nr-EoE and EE.

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Introduction: We compared esophageal mucosal gene transcript expression in proton pump inhibitor (PPI) responsive (PPI-R) eosinophilic esophagitis (EoE), PPI nonresponsive (PPI-NR) EoE, and healthy controls.

Methods: Transcript expression in midesophagus biopsies was determined using NanoString and a custom panel of EoE-specific genes. The top upregulated and downregulated genes with ≥2-fold difference in expression and statistically significant ( P < 0.

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Recurrent abdominal pain is a common reason for repeated visits to outpatient clinics and emergency departments, reflecting a substantial unmet need for timely and accurate diagnosis. A lack of awareness of some of the rarer causes of recurrent abdominal pain may impede diagnosis and delay effective management. This article identifies some of the key rare but diagnosable causes that are frequently missed by gastroenterologists and provides expert recommendations to support recognition, diagnosis, and management with the ultimate aim of improving patient outcomes.

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Background: Mast cell disorders including hereditary alpha tryptasemia (HαT) and idiopathic mast cell activation syndrome (MCAS) can be associated with neurologic symptoms such as orthostatic intolerance, pain, and cognitive impairment. The origin of these symptoms is not well understood.

Objective: To characterize neurologic findings in patients with HαT and MCAS through objective measurements.

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Article Synopsis
  • The American Initiative in Mast Cell Diseases (AIM) held its first conference at Stanford in May 2019 to form a Pan-American organization of experts in mast cell diseases.
  • AIM aims to create a collaborative network for researchers to enhance diagnostics, understand mast cell biology, and develop new therapies.
  • The proceedings address topics like hereditary alpha-tryptasemia, mast cell activation syndromes, and the diversity of mastocytosis, while also seeking international cooperation, particularly with the European Competence Network on Mastocytosis.
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Fecal microbiota transplantation (FMT) is a highly effective treatment for recurrent Clostridioides difficile infection (rCDI). However, standardization of FMT products is essential for its broad implementation into clinical practice. We have developed an oral preparation of freeze-dried, encapsulated microbiota, which is ~ 80% clinically effective, but results in delayed engraftment of donor bacteria relative to administration via colonoscopy.

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Background: Inflammatory bowel diseases (IBD) are often treated with anti-tumor necrosis factor alpha (anti-TNFα) medications. Concomitant treatment of IBD with anti-TNFα agents and immunomodulators appears to be associated with an increased risk for lymphoma.

Methods: Patients who developed lymphoma while on monotherapy with an anti-TNFα agent were identified at three centers.

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Patients with inflammatory bowel disease (IBD) develop coronavirus disease 2019 (COVID-19) at similar rates as the general population, and there was initial concern regarding potential for severe illness. Vaccinations were authorized for emergency use in the United States in December 2020 and aim to halt the spread of COVID-19. However, there are concerns that people will be hesitant to receive the vaccine for a variety of reasons including insufficient data in certain populations including those with IBD.

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