Publications by authors named "Meghan Kapp"

Lung injury in preterm infants leads to structural and functional respiratory deficits, with a risk for bronchopulmonary dysplasia (BPD) that in its most severe form is accompanied by pulmonary hypertension (PH). To examine cellular and molecular dynamics driving evolving BPD in humans, we performed single-cell RNA sequencing of preterm infant lungs in early stages of BPD and BPD+PH compared to term infants. Analysis of the endothelium revealed a unique aberrant capillary cell-state primarily in BPD+PH marked by expression.

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Context.—: Autopsies performed on COVID-19 patients have provided critical information about SARS-CoV-2's tropism, mechanisms of tissue injury, and spectrum of disease.

Objective.

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Background: Intramural hematoma during ablation for scar-related ventricular tachycardia (VT) is a rare but life-threatening complication.

Objectives: The goal of this study was to describe the features and outcomes of intramural hematoma during ablation for scar-related VT.

Methods: From 2010 to 2022, >3,514 ablations for ventricular arrhythmias were performed at 2 institutions.

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Objectives: Amyloid light chain (AL)-κ and AL-λ share common histopathologic changes; however, the potential difference in clinical manifestations, histologic findings, and clinical significance between the 2 subtypes remain unclear.

Methods: In a retrospective study, 94 kidney biopsies for AL amyloidosis were evaluated using the composite scarring injury score (CSIS) and amyloid score (AS). Results were then compared between AL-κ and AL-λ.

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Vasopressin has traditionally been thought to be produced by the neurohypophyseal system and then released into the circulation where it regulates water homeostasis. The questions of whether vasopressin could be produced outside of the brain and if the kidney could be a source of vasopressin are raised by the syndrome of inappropriate antidiuretic hormone secretion (vasopressin). We found that mouse and human kidneys expressed vasopressin mRNA.

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Article Synopsis
  • Cytomegalovirus (CMV) pneumonia is a serious condition often seen in patients after allogenic hematopoietic stem cell transplants, typically showing bilateral ground glass opacities on imaging, but it can present in various forms.
  • A case study of a 70-year-old man post-bone marrow transplant illustrated the aggressive progression of pulmonary nodules, leading to his rapid decline and eventual death before any clear infectious cause was determined.
  • Postmortem examinations confirmed the presence of CMV through microscopic analysis, highlighting the challenges in diagnosing and treating CMV pneumonia, especially in immunocompromised patients with rapidly advancing symptoms.
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Hemophagocytic lymphohistiocytosis (HLH) is a rare, aggressive hyperinflammatory syndrome in which an inciting event triggers massive, uninhibited activation of T lymphocytes and macrophages. Although viral infections are the most common trigger of HLH, cases of HSV-1 induced HLH are rare in adults. We present the case and postmortem findings of a 27-year-old woman diagnosed with HLH in the setting of immunosuppression for the treatment of granulomatosis with polyangiitis (GPA).

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Fetal akinesia deformation sequence (FADS), or Pena-Shokeir phenotype is a constellation of deformational changes resulting from decreased or absent fetal movement, and include arthrogryposis, and craniofacial and central nervous system anomalies. We report an autopsy case of a 36-6/7week female neonate with a normal female karyotype and chromosome microarray demonstrating findings consistent with FADS. We provide a detailed examination of the severe and complex central nervous system abnormalities, including marked pontocerebellar hypoplasia and cortical and cerebellar migration and gyration defects.

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Unlabelled: Transplantation of hepatitis C viremic (HCV+) deceased donor kidney transplants (DDKT) into aviremic (HCV-) recipients is a strategy to increase organ utilization. However, there are concerns around inferior recipient outcomes due to delayed initiation of direct-acting antiviral (DAA) therapy and sustained HCV replication when implemented outside of a research setting.

Methods: This was a retrospective single-center matched cohort study of DDKT recipients of HCV+ donors (cases) who were matched 1:1 to recipients of HCV- donors (comparators) by age, gender, race, presence of diabetes, kidney donor profile index, and calculated panel-reactive antibody.

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Article Synopsis
  • * The Banff Working Group introduced a new classification for PyVAN based on viral load and interstitial fibrosis levels to better understand and categorize the condition.
  • * In a study of 124 kidney transplant patients, the new classification did not effectively predict risk for graft failure, with class 3 showing the worst outcomes but no significant differences between classes 1 and 2; additional factors like post-transplant timing and inflammation also played a role in graft failure.
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A patient with a history of heart block and longstanding chloroquine use presented in cardiogenic shock refractory to medical therapy and mechanical circulatory support. Autopsy supported antimalarial-induced cardiomyopathy (AMIC). Progression of AMIC may be halted with early recognition and cessation of antimalarial therapy, highlighting importance of screening and timely diagnosis.

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Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has emerged into a worldwide pandemic of epic proportion. Beyond pulmonary involvement in coronavirus disease 2019 (COVID-19), a significant subset of patients experiences acute kidney injury. Patients who die from severe disease most notably show diffuse acute tubular injury on postmortem examination with a possible contribution of focal macro- and microvascular thrombi.

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The severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) pandemic has had devastating effects on global health and worldwide economy. Despite an initial reluctance to perform autopsies due to concerns for aerosolization of viral particles, a large number of autopsy studies published since May 2020 have shed light on the pathophysiology of Coronavirus disease 2019 (COVID-19). This review summarizes the histopathologic findings and clinicopathologic correlations from autopsies and biopsies performed in patients with COVID-19.

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Background: Renal mass biopsy (RMB) is a safe and accurate method for diagnosis and clinical management of renal masses. However, the non-diagnostic rate is a limiting factor. We tested the hypothesis that imaging characteristics and anatomic complexity of the mass may impact RMB diagnostic outcome using the preoperative aspects and dimensions used for an anatomical (PADUA) classification and radius-exophytic/endophytic-nearness-anterior/posterior-location (RENAL) score.

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Objectives: To study the pathologic spectrum of kidney diseases in patients with hepatitis C virus infection (HCV+).

Methods: Native kidney biopsy specimens in HCV+ patients were reviewed.

Results: A total of 9,836 native kidney biopsy specimens were evaluated from January 2007 to December 2016, of which 273 (2.

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Context.—: This study represents the largest compilation to date of clinical and postmortem data from decedents with coronavirus disease 2019 (COVID-19). It will augment previously published small series of autopsy case reports, refine clinicopathologic considerations, and improve the accuracy of future vital statistical reporting.

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Automatic instance segmentation of glomeruli within kidney whole slide imaging (WSI) is essential for clinical research in renal pathology. In computer vision, the end-to-end instance segmentation methods (e.g.

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Isolated reports of new-onset diabetes in individuals with COVID-19 have led to the hypothesis that SARS-CoV-2 is directly cytotoxic to pancreatic islet β cells. This would require binding and entry of SARS-CoV-2 into β cells via co-expression of its canonical cell entry factors, angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2); however, their expression in human pancreas has not been clearly defined. We analyzed six transcriptional datasets of primary human islet cells and found that ACE2 and TMPRSS2 were not co-expressed in single β cells.

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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) novel coronavirus 2019 (COVID-19) global pandemic has led to millions of cases and hundreds of thousands of deaths. While older adults appear at high risk for severe disease, hospitalizations and deaths due to SARS-CoV-2 among children have been relatively rare. Integrating single-cell RNA sequencing (scRNA-seq) of developing mouse lung with temporally resolved immunofluorescence in mouse and human lung tissue, we found that expression of SARS-CoV-2 Spike protein primer TMPRSS2 was highest in ciliated cells and type I alveolar epithelial cells (AT1), and TMPRSS2 expression increased with aging in mice and humans.

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Abnormal mitochondrial function is a well-recognized feature of acute and chronic kidney diseases. To gain insight into the role of mitochondria in kidney homeostasis and pathogenesis, we targeted mitochondrial transcription factor A (TFAM), a protein required for mitochondrial DNA replication and transcription that plays a critical part in the maintenance of mitochondrial mass and function. To examine the consequences of disrupted mitochondrial function in kidney epithelial cells, we inactivated TFAM in sine oculis-related homeobox 2-expressing kidney progenitor cells.

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