RESUMO
There is increasing attention for opportunistic pathogens such as Aspergillus fumigatus complicating SARS-CoV-2 infections in the critically ill. For invasive fungal disease, establishing a clear diagnosis can be challenging due to the invasiveness of diagnostic procedures required for a proven case. Here we present one of the first proven cases of COVID-19-associated pulmonary aspergillosis by positive culture of post-mortem lung biopsy.
RESUMO
Complement activation plays an important role in the pathogenesis of pneumonia. We hypothesized that inhibition of the complement system in the lungs by repeated treatment with nebulized plasma-derived human C1-esterase inhibitor reduces pulmonary complement activation and subsequently attenuates lung injury and lung inflammation. This was investigated in a rat model of severe Streptococcus pneumoniae pneumonia. Rats were intra-tracheally challenged with S. pneumoniae to induce pneumonia. Nebulized C1-esterase inhibitor or saline (control animals) was repeatedly administered to rats, 30 min before induction of pneumonia and every 6 h thereafter. Rats were sacrificed 20 or 40 h after inoculation with bacteria. Brochoalveolar lavage fluid and lung tissue were obtained for measuring levels of complement activation (C4b/c), lung injury and inflammation. Induction of pneumonia was associated with pulmonary complement activation (C4b/c at 20 h 1.24 % [0.56-2.59] and at 40 h 2.08 % [0.98-5.12], compared to 0.50 % [0.07-0.59] and 0.03 % [0.03-0.03] in the healthy control animals). The functional fraction of C1-INH was detectable in BALF, but no effect was found on pulmonary complement activation (C4b/c at 20 h 0.73 % [0.16-1.93] and at 40 h 2.38 % [0.54-4.19]). Twenty hours after inoculation, nebulized C1-esterase inhibitor treatment reduced total histology score, but this effect was no longer seen at 40 h. Nebulized C1-esterase inhibitor did not affect other markers of lung injury or lung inflammation. In this negative experimental animal study, severe S. pneumoniae pneumonia in rats is associated with pulmonary complement activation. Repeated treatment with nebulized C1-esterase inhibitor, although successfully delivered to the lungs, does not affect pulmonary complement activation, lung inflammation or lung injury.
Assuntos
Ativação do Complemento/efeitos dos fármacos , Proteína Inibidora do Complemento C1/farmacologia , Pneumonia/patologia , Streptococcus pneumoniae/patogenicidade , Animais , Líquido da Lavagem Broncoalveolar/química , Estudos de Casos e Controles , Complemento C4/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Interleucina-6/análise , Pulmão/metabolismo , Pulmão/patologia , Masculino , Pneumonia/metabolismo , Pneumonia/microbiologia , Ratos , Ratos Sprague-Dawley , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/análiseRESUMO
INTRODUCTION: Much controversy exists on the effect of a fresh frozen plasma (FFP) transfusion on systemic inflammation and endothelial damage. Adverse effects of FFP have been well described, including acute lung injury. However, it is also suggested that a higher amount of FFP decreases mortality in trauma patients requiring a massive transfusion. Furthermore, FFP has an endothelial stabilizing effect in experimental models. We investigated the effect of fresh frozen plasma transfusion on systemic inflammation and endothelial condition. METHODS: A prospective predefined substudy of a randomized trial in coagulopathic non-bleeding critically ill patients receiving a prophylactic transfusion of FFP (12 ml/kg) prior to an invasive procedure. Levels of inflammatory cytokines and markers of endothelial condition were measured in paired samples of 33 patients before and after transfusion. The statistical tests used were paired t test or the Wilcoxon signed-rank test. RESULTS: At baseline, systemic cytokine levels were mildly elevated in critically ill patients. FFP transfusion resulted in a decrease of levels of TNF-α (from 11.3 to 2.3 pg/ml, P = 0.01). Other cytokines were not affected. FFP also resulted in a decrease in systemic syndecan-1 levels (from 675 to 565 pg/ml, P = 0.01) and a decrease in factor VIII levels (from 246 to 246%, P <0.01), suggestive of an improved endothelial condition. This was associated with an increase in ADAMTS13 levels (from 24 to 32%, P <0.01) and a concomitant decrease in von Willebrand factor (vWF) levels (from 474 to 423%, P <0.01). CONCLUSIONS: A fixed dose of FFP transfusion in critically ill patients decreases syndecan-1 and factor VIII levels, suggesting a stabilized endothelial condition, possibly by increasing ADAMTS13, which is capable of cleaving vWF. TRIAL REGISTRATIONS: Trialregister.nl NTR2262, registered 26 March 2010 and Clinicaltrials.gov NCT01143909, registered 14 June 2010.
Assuntos
Estado Terminal/terapia , Células Endoteliais/efeitos dos fármacos , Inflamação/etiologia , Plasma/efeitos dos fármacos , Transfusão de Componentes Sanguíneos/métodos , Células Endoteliais/metabolismo , Humanos , Inflamação/complicações , Unidades de Terapia Intensiva/estatística & dados numéricos , Coeficiente Internacional Normatizado , Plasma/metabolismo , Estudos Prospectivos , Fator de Necrose Tumoral alfaRESUMO
Sepsis is characterized by a generalized inflammatory response and organ failure, associated with mitochondrial dysfunction. Hydrogen sulfide donor NaHS has anti-inflammatory properties, is able to reduce metabolism and can preserve mitochondrial morphology and function. Rats were challenged with live Streptococcus pneumonia or saline and infused with NaHS (36 µmol/kg/h) or vehicle. Lung and kidney injury markers were measured as well as mitochondrial function, viability and biogenesis. Infusion of NaHS reduced heart rate and body temperature, indicative of a hypo-metabolic state. NaHS infusion reduced sepsis-related lung and kidney injury, while host defense remained intact, as reflected by unchanged bacterial outgrowth. The reduction in organ injury was associated with a reversal of a fall in active oxidative phosphorylation with a concomitant decrease in ATP levels and ATP/ADP ratio. Preservation of mitochondrial respiration was associated with increased mitochondrial expression of α-tubulin and protein kinase C-ε, which acts as regulators of respiration. Mitochondrial damage was decreased by NaHS, as suggested by a reduction in mitochondrial DNA leakage in the lung. Also, NaHS treatment was associated with upregulation of peroxisome proliferator-activated receptor-γ coactivator 1α, with a subsequent increase in transcription of mitochondrial respiratory subunits. These findings indicate that NaHS reduces organ injury in pneumosepsis, possibly via preservation of oxidative phosphorylation and thereby ATP synthesis as well as by promoting mitochondrial biogenesis. Further studies on the involvement of mitochondria in sepsis are required.
Assuntos
Anti-Inflamatórios/farmacologia , Metabolismo Energético , Lesão Pulmonar/prevenção & controle , Pneumonia Pneumocócica/tratamento farmacológico , Sulfetos/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Modelos Animais de Doenças , Complexo I de Transporte de Elétrons/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/fisiopatologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Lesão Pulmonar/metabolismo , Lesão Pulmonar/microbiologia , Mitocôndrias/metabolismo , Renovação Mitocondrial/efeitos dos fármacos , Oxirredução , Pneumonia Pneumocócica/metabolismo , Pneumonia Pneumocócica/fisiopatologia , Proteína Quinase C-épsilon/metabolismo , Ratos , Ratos Sprague-Dawley , Sepse , Sulfetos/uso terapêutico , Tubulina (Proteína)/metabolismo , Regulação para CimaRESUMO
OBJECTIVE: To determine the effect of induced hypothermia on bacterial growth, lung injury, and mitochondrial function in a rat model of pneumococcal pneumosepsis. DESIGN: Animal study. SETTING: University research laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Subjects were inoculated intratracheally with Streptococcus pneumoniae and controls received saline. After the development of pneumonia, mechanical ventilation was started with or without induced mild hypothermia (32 °C). Bacterial growth and inflammatory markers were determined in bronchoalveolar lavage fluid, blood, and organs. Oxidative phosphorylation and adenosine triphosphate contents were measured in mitochondria isolated from the liver and soleus muscle. MEASUREMENTS AND MAIN RESULTS: Inoculation with S. pneumoniae resulted in severe pneumonia with bacterial dissemination, distal organ injury, and blunted peripheral oxygen consumption on mechanical ventilation. Hypothermia did not affect bacterial growth in bronchoalveolar lavage fluid and in homogenized lungs compared with normothermic controls but was associated with reduced bacterial dissemination to the spleen with a trend toward reduced bacterial load in blood and liver. Hypothermia reduced lung injury, exemplified by reductions in pulmonary cell influx and bronchoalveolar lavage fluid protein levels compared with controls. Hypothermia reduced bronchoalveolar lavage fluid levels of interleukin-1ß, tended to reduce bronchoalveolar lavage fluid CINC-3 levels, but no effect was observed on bronchoalveolar lavage fluid tumor necrosis factor-α and interleukin-6 levels. Induced hypothermia restored the fall in oxygen consumption and adenosine triphosphate levels in the liver, whereas adenosine triphosphate/adenosine diphosphate ratios remained low. In muscle, induced hypothermia also reversed low oxygen consumption as a result of pneumonia, but with an increase in adenosine triphosphate levels, whereas adenosine triphosphate/adenosine diphosphate ratios were low. CONCLUSION: Hypothermia did not adversely affect bacterial growth, but rather reduced bacterial dissemination in a rat model of pneumococcal pneumosepsis. Furthermore, hypothermia reduced lung injury associated with restored adenosine triphosphate availability and turnover. These findings suggest that hypothermia may reduce organ injury by preventing sepsis-related mitochondrial dysfunction.