Major discrepancy between clinical diagnosis of death and anatomopathological findings in adolescents with chronic diseases during 18-years

Objectives: To evaluate the inconsistency between clinical diagnosis of death and autopsy findings in adolescents with chronic diseases. Methods: A cross-sectional study including a sample of adolescents’ autopsies who died in a pediatric and adolescent tertiary hospital over 18 consecutive years. During this period, there were n = 2912 deaths, and n = 581/2912(20%) occurred in adolescents. Of these, n = 85/581(15%) underwent autopsies and were analyzed. Further results were divided into two groups: Goldman classes I or II (high disagreement between main clinical diagnosis of death and anatomopathological findings, n = 26) and Goldman classes III, IV or V (low or no disagreement between these two parameters, n = 59). Results: Median age at death (13.5 [10‒19] vs. 13 [10‒19] years, p = 0.495) and disease duration (22 [0‒164] vs. 20 [0‒200] months, p = 0.931), and frequencies for males (58% vs. 44%, p = 0.247) were similar between class I/II vs. class III/IV/V. The frequency of pneumonia (73% vs. 48%, p = 0.029), pulmonary abscess (12% vs. 0%, p = 0.026), as well as isolation of yeast (27% vs. 5%, p = 0.008), and virus (15% vs. 2%, p = 0.029) identified in the autopsy, were significantly higher in adolescents with Goldman class I/II compared to those with Goldman class III/IV/V. In contrast, cerebral edema was significantly lower in adolescents of the first group (4% vs. 25%, p = 0.018). Conclusion: This study showed that 30% of the adolescents with chronic diseases had major discrepancies between clinical diagnosis of death and autopsy findings. Pneumonia, pulmonary abscess, as well as isolation of yeast and virus were more frequently identified at autopsy findings in the groups with major discrepancies

Gene Expression Changes Associated with the Airway Wall Response to Injury

Understanding the way in which the airway heals in response to injury is fundamental to dissecting the mechanisms underlying airway disease pathology. As only limited data is available in relation to the in vivo characterisation of the molecular features of repair in the airway we sought to characterise the dynamic changes in gene expression that are associated with the early response to physical injury in the airway wall.We profiled gene expression changes in the airway wall using a large animal model of physical injury comprising bronchial brush biopsy in anaesthetised sheep. The experimental design featured sequential studies in the same animals over the course of a week and yielded data relating to the response at 6 hours, and 1, 3 and 7 days after injury. Notable features of the transcriptional response included the early and sustained preponderance of down-regulated genes associated with angiogenesis and immune cell activation, selection and differentiation. Later features of the response included the up-regulation of cell cycle genes at d1 and d3, and the latter pronounced up-regulation of extracellular matrix-related genes at d3 and d7.It is possible to follow the airway wall response to physical injury in the same animal over the course of time. Transcriptional changes featured coordinate expression of functionally related genes in a reproducible manner both within and between animals. This characterisation will provide a foundation against which to assess the perturbations that accompany airway disease pathologies of comparative relevance

Chronic OVA allergen challenged Siglec-F deficient mice have increased mucus, remodeling, and epithelial Siglec-F ligands which are up-regulated by IL-4 and IL-13

Abstract Background In this study we examined the role of Siglec-F, a receptor highly expressed on eosinophils, in contributing to mucus expression, airway remodeling, and Siglec-F ligand expression utilizing Siglec-F deficient mice exposed to chronic allergen challenge. Methods Wild type (WT) and Siglec-F deficient mice were sensitized and challenged chronically with OVA for one month. Levels of airway inflammation (eosinophils), Siglec-F ligand expresion and remodeling (mucus, fibrosis, smooth muscle thickness, extracellular matrix protein deposition) were assessed in lung sections by image analysis and immunohistology. Airway hyperreactivity to methacholine was assessed in intubated and ventilated mice. Results Siglec-F deficient mice challenged with OVA for one month had significantly increased numbers of BAL and peribronchial eosinophils compared to WT mice which was associated with a significant increase in mucus expression as assessed by the number of periodic acid Schiff positive airway epithelial cells. In addition, OVA challenged Siglec-F deficient mice had significantly increased levels of peribronchial fibrosis (total lung collagen, area of peribronchial trichrome staining), as well as increased numbers of peribronchial TGF-β1+ cells, and increased levels of expression of the extracellular matrix protein fibronectin compared to OVA challenged WT mice. Lung sections immunostained with a Siglec-Fc to detect Siglec-F ligand expression demonstrated higher levels of expression of the Siglec-F ligand in the peribronchial region in OVA challenged Siglec-F deficient mice compared to WT mice. WT and Siglec-F deficient mice challenged intranasally with IL-4 or IL-13 had significantly increased levels of airway epithelial Siglec-F ligand expression, whereas this was not observed in WT or Siglec-F deficient mice challenged with TNF-α. There was a significant increase in the thickness of the peribronchial smooth muscle layer in OVA challenged Siglec-F deficient mice, but this was not associated with significant increased airway hyperreactivity compared to WT mice. Conclusions Overall, this study demonstrates an important role for Siglec-F in modulating levels of chronic eosinophilic airway inflammation, peribronchial fibrosis, thickness of the smooth muscle layer, mucus expression, fibronectin, and levels of peribronchial Siglec-F ligands suggesting that Siglec-F may normally function to limit levels of chronic eosinophilic inflammation and remodeling. In addition, IL-4 and IL-13 are important regulators of Siglec-F ligand expression by airway epithelium

Lumican Expression in Diaphragm Induced by Mechanical Ventilation

Diaphragmatic dysfunction found in the patients with acute lung injury required prolonged mechanical ventilation. Mechanical ventilation can induce production of inflammatory cytokines and excess deposition of extracellular matrix proteins via up-regulation of transforming growth factor (TGF)-β1. Lumican is known to participate in TGF-β1 signaling during wound healing. The mechanisms regulating interactions between mechanical ventilation and diaphragmatic injury are unclear. We hypothesized that diaphragmatic damage by short duration of mechanical stretch caused up-regulation of lumican that modulated TGF-β1 signaling.Male C57BL/6 mice, either wild-type or lumican-null, aged 3 months, weighing between 25 and 30 g, were exposed to normal tidal volume (10 ml/kg) or high tidal volume (30 ml/kg) mechanical ventilation with room air for 2 to 8 hours. Nonventilated mice served as control groups.High tidal volume mechanical ventilation induced interfibrillar disassembly of diaphragmatic collagen fiber, lumican activation, type I and III procollagen, fibronectin, and α-smooth muscle actin (α-SMA) mRNA, production of free radical and TGF-β1 protein, and positive staining of lumican in diaphragmatic fiber. Mechanical ventilation of lumican deficient mice attenuated diaphragmatic injury, type I and III procollagen, fibronectin, and α-SMA mRNA, and production of free radical and TGF-β1 protein. No significant diaphragmatic injury was found in mice subjected to normal tidal volume mechanical ventilation.Our data showed that high tidal volume mechanical ventilation induced TGF-β1 production, TGF-β1-inducible genes, e.g., collagen, and diaphragmatic dysfunction through activation of the lumican

Static and dynamic mechanics of the murine lung after intratracheal bleomycin

<p>Abstract</p> <p>Background</p> <p>Despite its widespread use in pulmonary fibrosis research, the bleomycin mouse model has not been thoroughly validated from a pulmonary functional standpoint using new technologies. Purpose of this study was to systematically assess the functional alterations induced in murine lungs by fibrogenic agent bleomycin and to compare the forced oscillation technique with quasi-static pressure-volume curves in mice following bleomycin exposure.</p> <p>Methods</p> <p>Single intratracheal injections of saline (50 μL) or bleomycin (2 mg/Kg in 50 μL saline) were administered to C57BL/6 (<it>n </it>= 40) and Balb/c (<it>n </it>= 32) mice. Injury/fibrosis score, tissue volume density (TVD), collagen content, airway resistance (<it>R_N</it>), tissue damping (<it>G</it>) and elastance coefficient (<it>H</it>), hysteresivity (<it>η</it>), and area of pressure-volume curve (PV-A) were determined after 7 and 21 days (inflammation and fibrosis stage, respectively). Statistical hypothesis testing was performed using one-way ANOVA with LSD <it>post hoc </it>tests.</p> <p>Results</p> <p>Both C57BL/6 and Balb/c mice developed weight loss and lung inflammation after bleomycin. However, only C57BL/6 mice displayed cachexia and fibrosis, evidenced by increased fibrosis score, TVD, and collagen. At day 7, PV-A increased significantly and <it>G </it>and <it>H </it>non-significantly in bleomycin-exposed C57BL/6 mice compared to saline controls and further increase in all parameters was documented at day 21. <it>G </it>and <it>H</it>, but not PV-A, correlated well with the presence of fibrosis based on histology, TVD and collagen. In Balb/c mice, no change in collagen content, histology score, TVD, <it>H </it>and <it>G </it>was noted following bleomycin exposure, yet PV-A increased significantly compared to saline controls.</p> <p>Conclusions</p> <p>Lung dysfunction in the bleomycin model is more pronounced during the fibrosis stage rather than the inflammation stage. Forced oscillation mechanics are accurate indicators of experimental bleomycin-induced lung fibrosis. Quasi-static PV-curves may be more sensitive than forced oscillations at detecting inflammation and fibrosis.</p

Respiratory functional characteristics of human leptospirosis

Introdução: O comprometimento respiratório da leptospirose humana pode ser sua principal manifestação clínica e comumente está associado a maior morbimortalidade. Métodos: Objetivando descrever aspectos funcionais respiratórios nessa doença, foram analisados 21 pacientes com oximetrias de pulso e espirometrias em dois momentos: em avaliação inicial e após cerca de 28 dias. Resultados: Dois (9,5%) doentes tinham saturação periférica de oxigênio menor que 95%. Padrões espirométricos normais foram observados em 8 (38,1%) casos; distúrbios ventilatórios restritivos foram inferidos em 7 (33,3%), obstrutivos com capacidade vital forçada reduzida em 4 (19%), e inespecíficos em 2 (9,5%). Espirometrias anormais se associaram a pior escore APACHE II (p=0,02) e anormalidades na radiografia de tórax (p=0,05). Após resolução clínica, verificou-se ganho funcional significativo (p<0,05) no grupo de pacientes com espirometria alterada. Conclusões: Alterações espirométricas foram detectadas no curso da enfermidade e estiveram associadas a pior gravidade clínica e maior freqüência de anormalidades radiológicas torácicas. _________________________________________________________________________________________ ABSTRACT: Introduction: Respiratory impairment may be the main clinical manifestation of human leptospirosis. Methods: With the aim of describing the respiratory functional characteristics of this disease, 21 patients were evaluated using pulse oximetry and spirometry at two times: an initial evaluation and after around 28 days. Results: Two (9.5%) patients presented peripheral oxygen saturation of less than 95%. Normal spirometric patterns were observed in eight (38.1%); cases restrictive ventilatory disorders were inferred in seven (33.3%), obstructive disorders with reduced forced vital capacity in four (19%), and nonspecific disorders in two (9.5%). Abnormal spirometry findings were associated with worse APACHE II scores (p = 0.02) and abnormalities on chest x-ray (p = 0.05). After clinical resolution, significant functional gain was observed (p < 0.05) in the group of patients with abnormal spirometry findings. Conclusions: It was concluded that respiratory functional abnormalities were detected during the course of the disease and were associated with greater clinical severity and higher frequency of chest radiographic abnormalities

Morphological changes of carotid bodies in acute respiratory distress syndrome: a morphometric study in humans

Carotid bodies are chemoreceptors sensitive to a fall of partial oxygen pressure in blood (hypoxia). The morphological alterations of these organs in patients with chronic obstructive pulmonary disease (COPD) and in people living at high altitude are well known. However, it is not known whether the histological profile of human carotid bodies is changed in acute clinical conditions such as acute respiratory distress syndrome (ARDS). The objective of the present study was to perform a quantitative analysis of the histology of carotid bodies collected from patients who died of ARDS. A morphometric study of carotid bodies collected during routine autopsies was carried out on three groups: patients that died of non-respiratory diseases (controls, N = 8), patients that presented COPD and died of its complications or associated diseases (N = 7), and patients that died of ARDS (N = 7). Morphometric measurements of the volume fraction of clusters of chief cells were performed in five fields on each slide at 40X magnification. The numerical proportion of the four main histological cell types (light, dark, progenitor and sustentacular cells) was determined analyzing 10 fields on each slide at 400X magnification. The proportion of dark cells was 0.22 in ARDS patients, 0.12 in controls (P<0.001), and 0.08 in the COPD group. The proportion of light cells was 0.33 (ARDS), 0.44 (controls) (P<0.001), and 0.36 (COPD). These findings suggest that chronic and acute hypoxia have different effects on the histology of glomic tissue