Etiologic characteristics revealed by mNGS-mediated ultra-early and early microbiological identification in airway secretions from lung transplant recipients.

Background: Post-operative etiological studies are critical for infection prevention in lung transplant recipients within the first year. In this study, mNGS combined with microbial culture was applied to reveal the etiological characteristics within one week (ultra-early) and one month (early) in lung transplant recipients, and the epidemiology of infection occurred within one month. Methods: In 38 lung transplant recipients, deep airway secretions were collected through bronchofiberscope within two hours after the operation and were subjected to microbial identification by mNGS and microbial culture. The etiologic characteristics of lung transplant recipients were explored. Within one month, the infection status of recipients was monitored. The microbial species detected by mNGS were compared with the etiological agents causing infection within one month. Results: The detection rate of mNGS in the 38 airway secretions specimens was significantly higher than that of the microbial culture (P<0.0001). MNGS identified 143 kinds of pathogenic microorganisms; bacterial pathogens account for more than half (72.73%), with gram-positive and -negative bacteria occupying large proportions. Fungi such as Candida are also frequently detected. 5 (50%) microbial species identified by microbial culture had multiple drug resistance (MDR). Within one month, 26 (68.42%) recipients got infected (with a median time of 9 days), among which 10 (38.46%) cases were infected within one week. In the infected recipients, causative agents were detected in advance by mNGS in 9 (34.62%) cases, and most of them (6, 66.67%) were infected within one week (ultra-early). In the infection that occurred after one week, the consistency between mNGS results and the etiological agents was decreased. Conclusion: Based on the mNGS-reported pathogens in airway secretions samples collected within two hours, the initial empirical anti-infection regimes covering the bacteria and fungi are reasonable. The existence of bacteria with MDR forecasts the high risk of infection within 48 hours after transplant, reminding us of the necessity to adjust the antimicrobial strategy. The predictive role of mNGS performed within two hours in etiological agents is time-limited, suggesting continuous pathogenic identification is needed after lung transplant.

The diagnostic value of metagenomic next-generation sequencing for identifying Pneumocystis jirovecii infection in non-HIV immunocompromised patients.

Background: Pneumocystis jirovecii pneumonia (PJP) remains an important cause of morbidity and mortality in non-HIV immunocompromised patients especially in transplant recipients. But its diagnosis remains challenging due to the insuffificient performance of conventional methods for diagnosing Pneumocystis jirovecii(P. jirovecii) infection. Therefore, the auxiliary diagnostic function of metagenomics next-generation sequencing (mNGS) in clinical practice is worth of exploring. Method: 34 non-HIV immunocompromised patients who were diagnosed as PJP by clinical manifestations, imaging findings, immune status of the host, and Methenamine silver staining were tested by mNGS from October 2018 to December 2020 in Sichuan Provincial People's Hospital. The clinical performances of mNGS for P. jirovecii infection diagnosis were also evaluated with genome reads abundance and comparing with other traditional diagnostic methods. Results: We diagnosed a total of 34 non-HIV PJP patients by the clinical composite diagnosis. Our data shows that, compared with the clinical microbiological test, the detection rate of mNGS for P. jirovecii in non-HIV infected PJP patients is significantly higher than that of Methenamine silver staining and serum 1-3-ß-D-glucan. mNGS can be used as an auxiliary diagnostic tool to help diagnosis. The number of reads mapped to the genome of P. jirovecii and the duration of patients from onset to sampling collection were statistically significant between the two groups (Reads>100 and Reads ≤ 100) (8days vs. 23days, p=0.020). In addition, univariate analysis showed that C-reactive protein (15.8mg/L vs.79.56mg/L, p=0.016), lactate dehydrogenase (696U/l vs. 494U/l, p=0.030) and procalcitonin (0.09ng/ml vs. 0.59ng/ml, p=0.028) was also statistically significant between the two groups. Conclusions: An effective detection rate was achieved in PJP patients using mNGS testing of bronchoalveolar lavage fluid (BALF) or blood. The study also confirmed that the abundance of reads of P. jirovecii is related to the interval between the onset and sample collection. And the inflammation status during simultaneous mNGS detection might determine the abundance of pathogens. Hence, we conclude that the mNGS strategy could benefit disease diagnosis as well as treatment when complicated clinical infections appeared.

Sarco/endoplasmic reticulum Ca2+ ATPase (SERCA)-mediated ER stress crosstalk with autophagy is involved in tris(2-chloroethyl) phosphate stress-induced cardiac fibrosis.

Excessive organophosphate flame retardant (OPFR) use in consumer products has been reported to increase human disease susceptibility. However, the adverse effects of tris(2-chloroethyl) phosphate (TCEP) (a chlorinated alkyl OPFR) on the heart remain unknown. In this study, we tested whether cardiac fibrosis occurred in animal models of TCEP (10 mg/kg b.w./day) administered continuously by gavage for 30 days and evaluated the specific role of sarco/endoplasmic reticulum Ca2+ ATPase (SERCA). First, we confirmed that TCEP could trigger cardiac fibrosis by histopathological observation and cardiac fibrosis markers. We further verified that cardiac fibrosis occurred in animal models of TCEP exposure accompanied by SERCA2a, SERCA2b and SERCA2c downregulation. Notably, inductively coupled plasma-mass spectrometry (ICP-MS) analysis revealed that the cardiac concentrations of Ca2+ increased by 45.3% after TCEP exposure. Using 4-Isopropoxy-N-(2-methylquinolin-8-yl)benzamide (CDN1163, a small molecule SERCA activator), we observed that Ca2+ overload and subsequent cardiac fibrosis caused by TCEP were both alleviated. Simultaneously, the protein levels of endoplasmic reticulum (ER) markers (protein kinase R-like endoplasmic reticulum kinase (PERK), inositol requiring protein 1α (IRE1α), eukaryotic initiation factor 2 α (eIF2α)) were upregulated by TCEP, which could be abrogated by CDN1163 pretreatment. Furthermore, we observed that CDN1163 supplementation prevented overactive autophagy induced by TCEP in the heart. Mechanistically, TCEP could lead to Ca2+ overload by inhibiting the expression of SERCA, thereby triggering ER stress and overactive autophagy, eventually resulting in cardiac fibrosis. Together, our results suggest that the Ca2+ overload/ER stress/autophagy axis can act as a driver of cardiotoxicity induced by TCEP.

Optimization of Early Antimicrobial Strategies for Lung Transplant Recipients Based on Metagenomic Next-Generation Sequencing.

The management of perioperative antibiotic options after lung transplantation varies widely around the world, but there is a common trend to limit antibiotic use duration. Metagenomic next-generation sequencing (mNGS) has become a hot spot in clinical pathogen detection due to its precise, rapid, and wide detection spectrum of pathogens. Thus, we defined a new antibiotic regimen adjustment strategy in the very early stage (within 7 days) after lung transplantation mainly depending on mNGS reports combined with clinical conditions to reduce the use of antibiotics. To verify the clinical effect of the strategy, we carried out this research. Thirty patients who underwent lung transplantation were finally included, whose information including etiology, antibiotic adjustment, and the effect of our strategy was recorded. Lung transplant recipients in this study were prescribed with initial antibiotic regimen immediately after surgery; their antibiotic regimens were adjusted according to the strategy. According to our study, the entire effectiveness of the strategy was 90.0% (27/30). Besides, a total of 86 samples containing donor lung tissue, recipient lung tissue, and bronchoalveolar lavage fluid (BALF) were obtained in this study; they were all sent to mNGS test, while BALF was also sent to pathogen culture. Their results showed that the positive rate of BALF samples was higher (86.67%) than that of donor's lung tissue (20.0%) or recipient's lung tissue (13.33%) by mNGS test, indicating BALF samples are more valuable than other clinical samples from early postoperative period to guide the early adjustment of antibiotics after lung transplantation. It is effective for mNGS combined with traditional methods and clinical situations to optimize antibiotic regimens in lung transplantation recipients within 7 days after surgery.

Whole Genome Profiling of Lung Microbiome in Solid Organ Transplant Recipients Reveals Virus Involved Microecology May Worsen Prognosis.

Solid organ transplantation (SOT) is the final therapeutic option for recipients with end-stage organ failure, and its long-term success is limited by infections and chronic allograft dysfunction. Viral infection in SOT recipients is considered an important factor affecting prognosis. In this study, we retrospectively analyzed 43 cases of respiratory infections in SOT recipients using metagenomic next-generation sequencing (mNGS) for bronchoalveolar lavage fluid (BALF). At least one virus was detected in 26 (60.5%) recipients, while 17 (39.5%) were virus-negative. Among virus-positive recipients, cytomegalovirus (CMV) was detected in 14 (32.6%), Torque teno virus (TTV) was detected in 9 (20.9%), and other viruses were detected in 6 (14.0%). Prognostic analysis showed that the mortality of the virus-positive group was higher than that of the virus-negative group regardless whether it is the main cause of infection. Analysis of different types of viruses showed that the mortality of the CMV-positive group was significantly higher than that of the CMV-negative group, but no significant difference was observed in other type of virus groups. The diversity analysis of the lung microbiome showed that there was a significant difference between the virus-positive group and the negative group, in particular, the significant differences in microorganisms such as Pneumocystis jirovecii (PJP) and Moraxella osloensiswere detected. Moreover, in the presence of CMV, Pneumocystis jirovecii, Veillonella parvula, and other species showed dramatic changes in the lung of SOT patients, implying that high degree of co-infection between CMV and Pneumocystis jirovecii may occur. Taken together, our study shows that the presence of virus is associated with worse prognosis and dramatically altered lung microbiota in SOT recipients.

Elevated lncRNA-UCA1 upregulates EZH2 to promote inflammatory response in sepsis-induced pneumonia via inhibiting HOXA1.

Sepsis is characterized by a dysregulated inflammatory response. We aimed to explore the role of the long noncoding RNA urothelial carcinoma associated 1 (lncRNA UCA1)/enhancer of zeste homolog 2 (EZH2)/homeobox A1 (HOXA1) axis in sepsis-induced pneumonia. The sepsis rat models and RLE-6TN cellular sepsis-induced pneumonia models were established using ligation and puncture (CLP) and lipopolysaccharide (LPS). The expression of UCA1, EZH2, and HOXA1 in rat lung tissues and RLE-6TN cells was detected. Then, the CLP rats were respectively treated with lentivirus to upregulate or downregulate the expression of UCA1 and EZH2 to measure their roles in the pathology, apoptosis, inflammation and phosphorylated NF-κB p65(p-p65) levels in CLP rat lung tissues. UCA1 and EZH2 expression was upregulated or downregulated in LPS-induced RLE-6TN cells to explore their effects on cell viability, apoptosis, inflammation and p-p65 levels. The interactions among UCA1, EZH2, and HOXA1 were identified. UCA1 and EZH2 were upregulated whereas HOXA1 was downregulated in CLP rat lung tissues and LPS-induced RLE-6TN cells. Elevated UCA1 or increased EZH2 aggravated pathology and promoted apoptosis, inflammation and phosphorylated NF-κB p-65 levels in CLP rat lung tissues, and inhibited viability while facilitated apoptosis, inflammation and phosphorylated NF-κB p-65 levels in LPS-induced RLE-6TN cells. Silenced EZH2 reversed the effects of UCA1 elevation on sepsis-induced pneumonia. UCA1 suppressed HOXA1 expression through physically interacting with EZH2. UCA1 overexpression upregulates EZH2 to repress HOXA1 expression, thus aggravating the progression of sepsis-induced pneumonia, which could be alleviated by EZH2 inhibition.

Quantitative CT imaging features for COVID-19 evaluation: The ability to differentiate COVID-19 from non- COVID-19 (highly suspected) pneumonia patients during the epidemic period.

OBJECTIVES: COVID-19 and Non-Covid-19 (NC) Pneumonia encountered high CT imaging overlaps during pandemic. The study aims to evaluate the effectiveness of image-based quantitative CT features in discriminating COVID-19 from NC Pneumonia. MATERIALS AND METHODS: 145 patients with highly suspected COVID-19 were retrospectively enrolled from four centers in Sichuan Province during January 23 to March 23, 2020. 88 cases were confirmed as COVID-19, and 57 patients were NC. The dataset was randomly divided by 3:2 into training and testing sets. The quantitative CT radiomics features were extracted and screened sequentially by correlation analysis, Mann-Whitney U test, the least absolute shrinkage and selection operator (LASSO) logistic regression (LR) and backward stepwise LR with minimum AIC methods. The selected features were used to construct the LR model for differentiating COVID-19 from NC. Meanwhile, the differentiation performance of traditional quantitative CT features such as lesion volume ratio, ground glass opacity (GGO) or consolidation volume ratio were also considered and compared with Radiomics-based method. The receiver operating characteristic curve (ROC) analysis were conducted to evaluate the predicting performance. RESULTS: Compared with traditional CT quantitative features, radiomics features performed best with the highest Area Under Curve (AUC), sensitivity, specificity and accuracy in the training (0.994, 0.942, 1.0 and 0.965) and testing sets (0.977, 0.944, 0.870, 0.915) (Delong test, P < 0.001). Among CT volume-ratio based models using lesion or GGO component ratio, the model combining CT lesion score and component ratio performed better than others, with the AUC, sensitivity, specificity and accuracy of 0.84, 0.692, 0.853, 0.756 in the training set and 0.779, 0.667, 0.826, 0.729 in the testing set. The significant difference of the most selected wavelet transformed radiomics features between COVID-19 and NC might well reflect the CT signs. CONCLUSIONS: The differentiation between COVID-19 and NC could be well improved by using radiomics features, compared with traditional CT quantitative values.

Hemoglobin-Based Oxygen Carriers: Potential Applications in Solid Organ Preservation.

Ameliorating graft injury induced by ischemia and hypoxia, expanding the donor pool, and improving graft quality and recipient prognosis are still goals pursued by the transplant community. The preservation of organs during this process from donor to recipient is critical to the prognosis of both the graft and the recipient. At present, static cold storage, which is most widely used in clinical practice, not only reduces cell metabolism and oxygen demand through low temperature but also prevents cell edema and resists apoptosis through the application of traditional preservation solutions, but these do not improve hypoxia and increase oxygenation of the donor organ. In recent years, improving the ischemia and hypoxia of grafts during preservation and repairing the quality of marginal donor organs have been of great concern. Hemoglobin-based oxygen carriers (HBOCs) are "made of" natural hemoglobins that were originally developed as blood substitutes but have been extended to a variety of hypoxic clinical situations due to their ability to release oxygen. Compared with traditional preservation protocols, the addition of HBOCs to traditional preservation protocols provides more oxygen to organs to meet their energy metabolic needs, prolong preservation time, reduce ischemia-reperfusion injury to grafts, improve graft quality, and even increase the number of transplantable donors. The focus of the present study was to review the potential applications of HBOCs in solid organ preservation and provide new approaches to understanding the mechanism of the promising strategies for organ preservation.

New Applications of HBOC-201: A 25-Year Review of the Literature.

If not cured promptly, tissue ischemia and hypoxia can cause serious consequences or even threaten the life of the patient. Hemoglobin-based oxygen carrier-201 (HBOC-201), bovine hemoglobin polymerized by glutaraldehyde and stored in a modified Ringer's lactic acid solution, has been investigated as a blood substitute for clinical use. HBOC-201 was approved in South Africa in 2001 to treat patients with low hemoglobin (Hb) levels when red blood cells (RBCs) are contraindicated, rejected, or unavailable. By promoting oxygen diffusion and convective oxygen delivery, HBOC-201 may act as a direct oxygen donor and increase oxygen transfer between RBCs and between RBCs and tissues. Therefore, HBOC-201 is gradually finding applications in treating various ischemic and hypoxic diseases including traumatic hemorrhagic shock, hemolysis, myocardial infarction, cardiopulmonary bypass, perioperative period, organ transplantation, etc. However, side effects such as vasoconstriction and elevated methemoglobin caused by HBOC-201 are major concerns in clinical applications because Hbs are not encapsulated by cell membranes. This study summarizes preclinical and clinical studies of HBOC-201 applied in various clinical scenarios, outlines the relevant mechanisms, highlights potential side effects and solutions, and discusses the application prospects. Randomized trials with large samples need to be further studied to better validate the efficacy, safety, and tolerability of HBOC-201 to the extent where patient-specific treatment strategies would be developed for various clinical scenarios to improve clinical outcomes.

The effects of the 45° semi-recumbent position on the clinical outcomes of mechanically ventilated patients: a systematic review and meta-analysis study.

BACKGROUND: A meta-analysis was conducted to investigate the effects of the 45° semi-recumbent position on the clinical outcomes of mechanically ventilated patients. METHODS: The PubMed, Embase, and Cochrane medical databases were searched using the keywords "45°", "head-of-bed elevation", and "semi-recumbent". All relevant randomized controlled trials (RCTs) published between 2005 and 2021 were obtained. The Cochrane system for randomized intervention was adopted and the RevMan 5.3.5 software was used to construct forest plots and funnel plots to assess the risk of bias for the included studies. RESULTS: A total of 128 literatures were initially screened for this meta-analysis, and 7 studies were finally included, with a total of 740 patients. Meta-analysis revealed that the incidence of ventilator-associated pneumonia (VAP) was significantly lower in patients in the 45° semi-recumbent position compared to patients in the 30° semi-recumbent position [odds ratio (OR) =0.48; 95% confidence interval (CI): 0.28 to 0.84; Z=2.59; P=0.009]. Furthermore, the incidence of gastric reflux was significantly lower in patients in the 45° semi-recumbent position compared to patients in the 30° semi-recumbent position (OR =0.50; 95% CI: 0.27 to 0.96; Z=2.09; P=0.04). Meta-analysis demonstrated that the incidence of pressure sores was significantly higher in patients in the 45° semi-recumbent position compared to patients in the 30° semi-recumbent position (OR =1.88; 95% CI: 1.05 to 3.36; Z=2.11; P=0.03). DISCUSSION: The 45° semi-recumbent position can reduce the incidence of VAP and gastric reflux in patients undergoing mechanical ventilation (MV), but it may also increase the risk of pressure sores. Thus, consideration should be made based on a comprehensive understanding of the patient's condition and physical state.

A Retrospective Paired Comparison Between Untargeted Next Generation Sequencing and Conventional Microbiology Tests With Wisely Chosen Metagenomic Sequencing Positive Criteria.

Objectives: To evaluate the performance of metagenomic next generation sequencing (mNGS) using adequate criteria for the detection of pathogens in lower respiratory tract (LRT) samples with a paired comparison to conventional microbiology tests (CMT). Methods: One hundred sixty-seven patients were reviewed from four different intensive care units (ICUs) in mainland China during 2018 with both mNGS and CMT results of LRT samples available. The reads per million ratio (RPMsample/RPMnon-template-control ratio) and standardized strictly mapped reads number (SDSMRN) were the two criteria chosen for identifying positive pathogens reported from mNGS. A McNemar test was used for a paired comparison analysis between mNGS and CMT. Results: One hundred forty-nine cases were counted into the final analysis. The RPMsample/RPMNTC ratio criterion performed better with a higher accuracy for bacteria, fungi, and virus than SDSMRN criterion [bacteria (RPMsample/RPMNTC ratio vs. SDSMRN), 65.1 vs. 55.7%; fungi, 75.8 vs. 71.1%; DNA virus, 86.3 vs. 74.5%; RNA virus, 90.9 vs. 81.8%]. The mNGS was also superior in bacteria detection only if an SDSMRN ≥3 was used as a positive criterion with a paired comparison to culture [SDSMRN positive, 92/149 (61.7%); culture positive, 54/149 (36.2%); p < 0.001]; however, it was outperformed with significantly more fungi and DNA virus identification when choosing both criteria for positive outliers [fungi (RPMsample/RPMNTC ratio vs. SDSMRN vs. culture), 23.5 vs. 29.5 vs. 8.7%, p < 0.001; DNA virus (RPMsample/RPMNTC ratio vs. SDSMRN vs. PCR), 14.1 vs. 20.8 vs. 11.8%, p < 0.05]. Conclusions: Metagenomic next generation sequencing may contribute to revealing the LRT infection etiology in hospitalized groups of potential fungal infections and in situations with less access to the multiplex PCR of LRT samples from the laboratory by choosing a wise criterion like the RPMsample/RPMNTC ratio.

[Prognostic value of transthoracic lung ultrasound comet-tail and extravascular lung water index in septic patients].

OBJECTIVE: To evaluate the prognostic value of transthoracic lung ultrasound comet-tail and extravascular lung water index (EVLWI) in septic patients. METHODS: A prospective cohort study was conducted. Sixty septic patients admitted to department of intensive care unit (ICU) of Sichuan Provincial People's Hospital from November 2016 to October 2019 were enrolled. The EVLWI and pulmonary vascular permeability index (PVPI) were determined by pulse-indicated continuous cardiac output (PiCCO) system at 0, 24, 48 and 72 hours. At the same time, the numbers of comet tail signs in both lungs (parasternal, midclavicular, axillary to midaxillary) were collected by chest ultrasound. Moreover, arterial blood gas analysis, such as pH value, central venous-to-arterial carbon dioxide difference (Pcv-aCO2), central venous oxygen saturation (ScvO2), blood lactic acid (Lac), PaO2/FiO2 were measured. Pearson correlation analysis was performed between the number of comet-tail sign and EVLWI. Multivariate Logistic regression model was used to analyze the relationship between the number of comet-tail sign, EVLWI and prognosis. Receiver operator characteristic curve (ROC curve) was drawn to predict the prognosis. RESULTS: There were 43 males and 17 females in 60 septic patients. The average age was (64.3±15.5) years old (range: 31-83 years old). There were 35 cases with pulmonary infection, 10 cases with abdominal infection, 6 cases with urinary tract infection, 3 cases with skin and soft tissue infection, 3 cases with intestinal infection, 1 case with meningitis, 1 case with cellulitis and 1 case with multiple injury. Acute respiratory distress syndrome (ARDS) occurred with 8 patients; 40 patients (66.7%) survived and 20 patients (33.3%) died on day 28. Pearson correlation analysis showed that the number of comet-tail sign was positively correlated with EVLWI (r = 0.944, P < 0.001). There was significant difference in the number of comet-tail signs among sepsis patients with different primary infection sites (H = 17.714, P < 0.001). The number of comet-tail signs in sepsis patients with pulmonary infection [19 (13, 27)] was significantly higher than that with other infections. The number of comet-tail sign in patients with ARDS was significantly higher than that in patients without ARDS [27 (19, 30) vs. 15 (9, 24), H = 25.387, P < 0.001]. Multivariate Logistic regression analysis showed that EVLWI, the number of comet-tail signs and PVPI were independent risk factors for death in septic patients [odds ratio (OR) and 95% confidence interval (95%CI) were 10.772 (1.161-99.851), 2.360 (1.070-5.202), 2.042 (1.152-3.622), all P < 0.05]. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value of Logistic regression model based on comet-tail sign and EVLWI were 90.0%, 90.0%, 90.0%, 81.8%, 94.7%, respectively, and area under curve (AUC) were 0.926±0.018, 95%CI was 0.912-0.975, P < 0.001. CONCLUSIONS: The transthoracic lung ultrasound comet-tail in septic patients is significantly correlated with EVLWI monitored by PiCCO. The transthoracic lung ultrasound comet-tail combined with EVLWI can better improve the sensitivity, specificity and accuracy of 28-day prognosis in septic patients.

Early Detection of Legionella pneumophila and Aspergillus by mNGS in a Critically Ill Patient With Legionella Pneumonia After Extracorporeal Membrane Oxygenation Treatment: Case Report and Literature Review.

Legionella pneumophila can cause pneumonia, leading to severe acute respiratory distress syndrome (ARDS). Because of its harsh growth requirements, limited detection methods, and non-specific clinical manifestations, diagnosing Legionella pneumonia remains still challenging. Metagenomic next-generation sequencing (mNGS) technology has increased the rate of detection of Legionella. This study describes a patient who rapidly progressed to severe ARDS during the early stage of infection and was treated with extracorporeal membrane oxygenation (ECMO). Although his bronchoalveolar lavage fluid (BALF) was negative for infection and his serum was negative for anti-Legionella antibody, mNGS of his BALF and blood showed only the presence of Legionella pneumophila (blood mNGS reads 229, BALF reads 656). After antibiotic treatment and weaning from ECMO, however, he developed a secondary Aspergillus and Klebsiella pneumoniae infection as shown by mNGS. Mechanical ventilation and antibiotic treatment were effective. A search of PubMed showed few reports of secondary Aspergillus infections after Legionella infection. Severe pneumonia caused by any type of pathogenic bacteria may be followed by Aspergillus infection, sometimes during extremely early stages of infection. Patients with severe pneumonia caused by Legionella infection should undergo early screening for secondary infections using methods such as mNGS, enabling early and precise treatment, thereby simplifying the use of antibiotics and improving patient prognosis.

How to optimize the Radiology protocol during the global COVID-19 epidemic: Keypoints from Sichuan Provincial People's Hospital.

Currently, the COVID-19 pneumonia epidemic is spreading worldwide. Pulmonary imaging plays an important role. The pulmonary imaging (chest computed tomography and Digital radiography) are indispensable for definitive diagnosis and reexamination. It should be noted that nosocomial infection is not uncommon. Many cases including health workers are infected. This is the experience of our radiology department's protocols during the outbreak, we used this protocol to cope with the COVID-19 in Sichuan Province， besides，there is zero infection for health workers during the whole epidemic. So, we would like to share our experience to other radiologists to avoid the nosocomial infection as low as possible. We have six key points for updating the protocol in the epidemic period of COVID-19: 1. Triage system: three-level triage, 2. Maximum Protection Principle, 3. Technical operation principle: careful, fast and stable, 4. Radiologist's Responsibility and Notice, 5. Disinfection measures of machine room, 6. Hospital information construction, network office, accelerate the sharing of imaging, and carry out MDT consultation.