Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of an ongoing pandemic, with increasing deaths worldwide. To date, documentation of the histopathological features in fatal ...cases of the disease caused by SARS-CoV-2 (COVID-19) has been scarce due to sparse autopsy performance and incomplete organ sampling. We aimed to provide a clinicopathological report of severe COVID-19 cases by documenting histopathological changes and evidence of SARS-CoV-2 tissue tropism.
In this case series, patients with a positive antemortem or post-mortem SARS-CoV-2 result were considered eligible for enrolment. Post-mortem examinations were done on 14 people who died with COVID-19 at the King County Medical Examiner's Office (Seattle, WA, USA) and Snohomish County Medical Examiner's Office (Everett, WA, USA) in negative-pressure isolation suites during February and March, 2020. Clinical and laboratory data were reviewed. Tissue examination was done by light microscopy, immunohistochemistry, electron microscopy, and quantitative RT-PCR.
The median age of our cohort was 73·5 years (range 42–84; IQR 67·5–77·25). All patients had clinically significant comorbidities, the most common being hypertension, chronic kidney disease, obstructive sleep apnoea, and metabolic disease including diabetes and obesity. The major pulmonary finding was diffuse alveolar damage in the acute or organising phases, with five patients showing focal pulmonary microthrombi. Coronavirus-like particles were detected in the respiratory system, kidney, and gastrointestinal tract. Lymphocytic myocarditis was observed in one patient with viral RNA detected in the tissue.
The primary pathology observed in our cohort was diffuse alveolar damage, with virus located in the pneumocytes and tracheal epithelium. Microthrombi, where observed, were scarce and endotheliitis was not identified. Although other non-pulmonary organs showed susceptibility to infection, their contribution to the pathogenesis of SARS-CoV-2 infection requires further examination.
None.
Recent breakthroughs in 3-dimensional (3D) organoid cultures for many organ systems have led to new physiologically complex in vitro models to study human development and disease. Here, we report the ...step-wise differentiation of human pluripotent stem cells (hPSCs) (embryonic and induced) into lung organoids. By manipulating developmental signaling pathways hPSCs generate ventral-anterior foregut spheroids, which are then expanded into human lung organoids (HLOs). HLOs consist of epithelial and mesenchymal compartments of the lung, organized with structural features similar to the native lung. HLOs possess upper airway-like epithelium with basal cells and immature ciliated cells surrounded by smooth muscle and myofibroblasts as well as an alveolar-like domain with appropriate cell types. Using RNA-sequencing, we show that HLOs are remarkably similar to human fetal lung based on global transcriptional profiles, suggesting that HLOs are an excellent model to study human lung development, maturation and disease.
To investigate the characteristics and risk factors of a novel parenchymal lung disease (LD), increasingly detected in systemic juvenile idiopathic arthritis (sJIA).
In a multicentre retrospective ...study, 61 cases were investigated using physician-reported clinical information and centralised analyses of radiological, pathological and genetic data.
LD was associated with distinctive features, including acute erythematous clubbing and a high frequency of anaphylactic reactions to the interleukin (IL)-6 inhibitor, tocilizumab. Serum ferritin elevation and/or significant lymphopaenia preceded LD detection. The most prevalent chest CT pattern was septal thickening, involving the periphery of multiple lobes ± ground-glass opacities. The predominant pathology (23 of 36) was pulmonary alveolar proteinosis and/or endogenous lipoid pneumonia (PAP/ELP), with atypical features including regional involvement and concomitant vascular changes. Apparent severe delayed drug hypersensitivity occurred in some cases. The 5-year survival was 42%. Whole exome sequencing (20 of 61) did not identify a novel monogenic defect or likely causal PAP-related or macrophage activation syndrome (MAS)-related mutations. Trisomy 21 and young sJIA onset increased LD risk. Exposure to IL-1 and IL-6 inhibitors (46 of 61) was associated with multiple LD features. By several indicators, severity of sJIA was comparable in drug-exposed subjects and published sJIA cohorts. MAS at sJIA onset was increased in the drug-exposed, but was not associated with LD features.
A rare, life-threatening lung disease in sJIA is defined by a constellation of unusual clinical characteristics. The pathology, a PAP/ELP variant, suggests macrophage dysfunction. Inhibitor exposure may promote LD, independent of sJIA severity, in a small subset of treated patients. Treatment/prevention strategies are needed.
Pulmonary neuroendocrine cells (PNECs) are rare airway epithelial cells whose function is poorly understood. Here we show that
-mutant mice that have no PNECs exhibit severely blunted mucosal type 2 ...response in models of allergic asthma. PNECs reside in close proximity to group 2 innate lymphoid cells (ILC2s) near airway branch points. PNECs act through calcitonin gene-related peptide (CGRP) to stimulate ILC2s and elicit downstream immune responses. In addition, PNECs act through the neurotransmitter γ-aminobutyric acid (GABA) to induce goblet cell hyperplasia. The instillation of a mixture of CGRP and GABA in
-mutant airways restores both immune and goblet cell responses. In accordance, lungs from human asthmatics show increased PNECs. These findings demonstrate that the PNEC-ILC2 neuroimmunological modules function at airway branch points to amplify allergic asthma responses.
Children's interstitial and diffuse lung disease (chILD) comprises a large number of diverse entities ranging from disorders of lung development, maturation and function unique in infancy to ...immune-mediated, environmental, vascular and other conditions overlapping with adult disease. Pathologic evaluation of the lung has played a central role in characterizing many of these disorders, resulting in revised nomenclature and classifications to help guide clinical management(1-4). Technological advancements are rapidly uncovering genetic and molecular underpinnings of these conditions, as well as widening the phenotypes which bridge adult disease, often reducing the perceived need for diagnostic lung biopsy. As such the decision to get a lung biopsy in chILD is frequently for rapid ascertainment of disease in a critically ill child or when clinical presentation, imaging and laboratory studies fail to provide a cohesive diagnosis needed for treatment. While there have been modifications in surgical procedures for lung biopsy that minimize postoperative morbidity, it remains a high-risk invasive procedure, especially in a medically complex patient(5). Thus, it is essential that the lung biopsy be handled properly to maximize diagnostic yield, including close communication between the clinician, radiologist, surgeon, and pathologist before biopsy to determine best sampling site(s) and prioritization of tissue utilization. This review provides an overview of optimal handling and evaluation of a surgical lung biopsy for suspected chILD, with emphasis on specific conditions in which pathologic features play a critical role in providing an integrated diagnosis and guiding management.
Objective
Recent observations in systemic juvenile idiopathic arthritis (JIA) suggest an increasing incidence of high‐mortality interstitial lung disease often characterized by a variant of pulmonary ...alveolar proteinosis (PAP). Co‐occurrence of macrophage activation syndrome (MAS) and PAP in systemic JIA suggests a shared pathology, but patients with lung disease associated with systemic JIA (designated SJIA‐LD) also commonly experience features of drug reaction such as atypical rashes and eosinophilia. This study was undertaken to investigate immunopathology and identify biomarkers in systemic JIA, MAS, and SJIA‐LD.
Methods
We used SOMAscan to measure ~1,300 analytes in sera from healthy controls and patients with systemic JIA, MAS, SJIA‐LD, or other related diseases. We verified selected findings by enzyme‐linked immunosorbent assay and lung immunostaining. Because the proteome of a sample may reflect multiple states (systemic JIA, MAS, or SJIA‐LD), we used regression modeling to identify subsets of altered proteins associated with each state. We tested key findings in a validation cohort.
Results
Proteome alterations in active systemic JIA and MAS overlapped substantially, including known systemic JIA biomarkers such as serum amyloid A and S100A9, and novel elevations in the levels of heat‐shock proteins and glycolytic enzymes. Interleukin‐18 levels were elevated in all systemic JIA groups, particularly MAS and SJIA‐LD. We also identified an MAS‐independent SJIA‐LD signature notable for elevated levels of intercellular adhesion molecule 5 (ICAM‐5), matrix metalloproteinase 7 (MMP‐7), and allergic/eosinophilic chemokines, which have been previously associated with lung damage. Immunohistochemistry localized ICAM‐5 and MMP‐7 in the lungs of patients with SJIA‐LD. The ability of ICAM‐5 to distinguish SJIA‐LD from systemic JIA/MAS was independently validated.
Conclusion
Serum proteins support a systemic JIA–to‐MAS continuum; help distinguish systemic JIA, systemic JIA/MAS, and SJIA‐LD; and suggest etiologic hypotheses. Select biomarkers, such as ICAM‐5, could aid in early detection and management of SJIA‐LD.
Childhood interstitial lung disease (chILD) comprises a spectrum of rare diffuse lung disorders. chILD is heterogeneous in origin, with different disease manifestations occurring in the context of ...ongoing lung development. The large number of disorders in chILD, in combination with the rarity of each diagnosis, has hampered scientific and clinical progress within the field. Epidemiologic and natural history data are limited. The prognosis varies depending on the etiology, with some forms progressing to lung transplant or death. There are limited treatment options for patients with chILD. Although U.S. Food and Drug Administration-approved treatments are now available for adult patients with idiopathic pulmonary fibrosis, no clinical trials have been conducted in a pediatric population using agents designed to treat lung fibrosis. This review will focus on progressive chILD disorders and on the urgent need for meaningful objective outcome measures to define, detect, and monitor fibrosis in children.
Cystic fibrosis-related diabetes (CFRD) is a common complication of cystic fibrosis (CF), increasing patient morbidity and mortality. Poor understanding of CFRD pathogenesis limits the development of ...targeted therapies to treat and/or prevent the disease. The aim of this study was to evaluate islet pathology, specifically, inflammation, amyloid deposition, and endocrine cell composition in subjects with CF with diabetes and with CF without diabetes.
A retrospective analysis of archived pancreas tissue collected at autopsy was conducted using pancreas tissue from subjects with CF and diabetes (CFRD) (
= 18) and CF without diabetes (CF-no DM) (
= 17). Two cohorts of control non-CF subjects were identified, each matched to CFRD and CF-no DM subjects for age, sex, and BMI (non-CF older,
= 20, and non-CF younger,
= 20), respectively. Immunohistochemistry was performed to assess interleukin-1β (IL-1β) and islet hormone (insulin, glucagon, somatostatin, and pancreatic polypeptide) immunoreactivity; histochemistry was performed to quantify amyloid deposition.
Islet IL-1β immunoreactivity was substantially increased in both CFRD and CF-no DM subjects compared with non-CF subjects and was common in young subjects with CF (≤10 years of age). In contrast, islet amyloid deposition was increased only in CFRD subjects. We also observe abnormal islet hormone immunoreactivity, characterized by increased glucagon immunoreactivity, in CF-no DM and CFRD subjects compared with non-CF subjects.
These findings reveal novel molecular pathways and therapeutic targets underlying islet pathology in CF subjects and may be important in developing new approaches to treat CFRD.
To evaluate the clinical usefulness of rapid exome sequencing (rES) in critically ill children with likely genetic disease using a standardized process at a single institution. To provide evidence ...that rES with should become standard of care for this patient population.
We implemented a process to provide clinical-grade rES to eligible children at a single institution. Eligibility included (a) recommendation of rES by a consulting geneticist, (b) monogenic disorder suspected, (c) rapid diagnosis predicted to affect inpatient management, (d) pretest counseling provided by an appropriate provider, and (e) unanimous approval by a committee of 4 geneticists. Trio exome sequencing was sent to a reference laboratory that provided verbal report within 7-10 days. Clinical outcomes related to rES were prospectively collected. Input from geneticists, genetic counselors, pathologists, neonatologists, and critical care pediatricians was collected to identify changes in management related to rES.
There were 54 patients who were eligible for rES over a 34-month study period. Of these patients, 46 underwent rES, 24 of whom (52%) had at least 1 change in management related to rES. In 20 patients (43%), a molecular diagnosis was achieved, demonstrating that nondiagnostic exomes could change medical management in some cases. Overall, 84% of patients were under 1 month old at rES request and the mean turnaround time was 9 days.
rES testing has a significant impact on the management of critically ill children with suspected monogenic disease and should be considered standard of care for tertiary institutions who can provide coordinated genetics expertise.
PDF
