Necrotizing pneumonia due to Pseudomonas aeruginosa secondary to severe COVID-19 pneumonia.

Necrotizing pneumonia (NP) can occur as a secondary infection even if the clinical course of COVID-19 pneumonia is favorable, particularly in patients on mechanical ventilation and under immunosuppression.

Clostridium butyricum-induced ω-3 fatty acid 18-HEPE elicits anti-influenza virus pneumonia effects through interferon-λ upregulation.

The precise mechanism by which butyrate-producing bacteria in the gut contribute to resistance to respiratory viral infections remains to be elucidated. Here, we describe a gut-lung axis mechanism and report that orally administered Clostridium butyricum (CB) enhances influenza virus infection resistance through upregulation of interferon (IFN)-λ in lung epithelial cells. Gut microbiome-induced ω-3 fatty acid 18-hydroxy eicosapentaenoic acid (18-HEPE) promotes IFN-λ production through the G protein-coupled receptor (GPR)120 and IFN regulatory factor (IRF)-1/-7 activations. CB promotes 18-HEPE production in the gut and enhances ω-3 fatty acid sensitivity in the lungs by promoting GPR120 expression. This study finds a gut-lung axis mechanism and provides insights into the treatments and prophylaxis for viral respiratory infections.

The pathophysiological mechanisms of COVID-19 and host immunity, with emphasis on the dysbiosis of the lung and gut microbiomes and pregnancy.

The coronavirus 2019 (COVID-19) pandemic is a health and economic crisis. It has also highlighted human relational problems, such as racism and conflicts between nations. Although vaccination programs against the severe respiratory syndrome coronavirus 2 (SARS-CoV-2) have started worldwide, the pandemic is ongoing, and people are struggling. The mechanism of disease severity in COVID-19 is multifactorial, complicated, and affected by viral pathogenesis. For example, monocyte dysfunction due to aging and respiratory and gut dysbiosis influence the host's immunity against SARS-CoV-2 including helper T-cell imbalance and viral clearance reduction, leading to accelerated disease progression in older patients or those with underlying diseases. The different immune responses against SARS-CoV-2 also contribute to various radiological findings, including that of acute respiratory distress syndrome, which is associated with high mortality, especially in patients susceptible to disease progression. We aimed to review the pathophysiological mechanisms involved in COVID-19, with emphasis on the altered microbiome in the lung and gut, and the different radiological findings in different patient groups, such as younger adults and pregnant women.

COVID-19 Modulates Inflammatory and Renal Markers That May Predict Hospital Outcomes among African American Males.

BACKGROUND AND OBJECTIVES: African Americans and males have elevated risks of infection, hospitalization, and death from SARS-CoV-2 in comparison with other populations. We report immune responses and renal injury markers in African American male patients hospitalized for COVID-19. METHODS: This was a single-center, retrospective study of 56 COVID-19 infected hospitalized African American males 50+ years of age selected from among non-intensive care unit (ICU) and ICU status patients. Demographics, hospitalization-related variables, and medical history were collected from electronic medical records. Plasma samples collected close to admission (≤2 days) were evaluated for cytokines and renal markers; results were compared to a control group (n = 31) and related to COVID-19 in-hospital mortality. RESULTS: Among COVID-19 patients, eight (14.2%) suffered in-hospital mortality; seven (23.3%) in the ICU and one (3.8%) among non-ICU patients. Interleukin (IL)-18 and IL-33 were elevated at admission in COVID-19 patients in comparison with controls. IL-6, IL-18, MCP-1/CCL2, MIP-1α/CCL3, IL-33, GST, and osteopontin were upregulated at admission in ICU patients in comparison with controls. In addition to clinical factors, MCP-1 and GST may provide incremental value for risk prediction of COVID-19 in-hospital mortality. CONCLUSIONS: Qualitatively similar inflammatory responses were observed in comparison to other populations reported in the literature, suggesting non-immunologic factors may account for outcome differences. Further, we provide initial evidence for cytokine and renal toxicity markers as prognostic factors for COVID-19 in-hospital mortality among African American males.

Comparative study of SmartAmp assay and reverse transcription-polymerase chain reaction by saliva specimen for the diagnosing COVID-19.

INTRODUCTION: The pandemic of a novel coronavirus disease 2019 (COVID-19) caused by a severe acute respiratory coronavirus 2 (SARS-CoV-2) infection has been problematic worldwide. A new SARS-CoV-2 diagnostic test (SmartAmp) was licensed in Japan in July 2021. This method, which enables us to diagnose COVID-19 as well as a gene mutation on the virus, is promising to reduce medical costs and staff labor. PATIENTS AND METHODS: To analyze the diagnostic accuracy of the SmartAmp assay for diagnosing COVID-19, we performed this retrospective study at our institute during April and May 2021. We compared the results of the SmartAmp assay and real-time reverse transcription-polymerase chain reaction (rRT-PCR) using a saliva sample from individuals suspected as having COVID-19. RESULTS: Out of 70 samples tested, the SmartAmp assay had 50 (71%) positive and 20 (29%) negative results. Using rRT-PCR as a reference, the diagnostic accuracy displayed a sensitivity of 84%, a specificity of 95%, a positive predictive value of 97.7%, and a negative predictive value of 70.4%. On the other hand, false-negative cases were found in 7 (10%), and there was no significant difference of Ct-value between true positive and false negative cases (Mean Ct-value 25.2 vs. 27.5 cycles, p = 0.226 by Mann-Whitney U test). CONCLUSION: The SmartAmp assay is a valuable method to diagnose COVID-19 rapidly. However, the negative predictive value is not high enough to diagnose the disease, so that negative results should be considered for rRT-PCR testing if patients are suspected of having COVID-19.

Efficacy and validity of automated quantitative chemiluminescent enzyme immunoassay for SARS-CoV-2 antigen test from saliva specimen in the diagnosis of COVID-19.

INTRODUCTION: The pandemic of a novel coronavirus disease 2019 (COVID-19) caused by a severe acute respiratory coronavirus 2 (SARS-CoV-2) infection has been problematic worldwide. A new SARS-CoV-2 antigen test (LUMIPULSEⓇ) was licensed and widely used in Japan since May 2020. We conducted this study intending to whether the automated quantitative CLEIA antigen test using a saliva sample is effective and valid for the diagnosis of COVID-19. PATIENTS AND METHODS: We analyzed and compared the diagnostic accuracy of both the automated quantitative CLEIA antigen test and real-time RT-PCR (rRT-PCR) using a saliva sample from individuals suspected as having COVID-19. RESULTS: A total of 305 samples were collected and tested in Aichi Medical University Hospital and affiliated facilities from December 2020 until January 2021 at our institute. Using reverse-transcription PCR as a reference, the AUROC of the automated quantitative CLEIA antigen test was 0.903 (95% confidential interval 0.845-0.962, p < 0.001). The appropriate cut-off antigen level was 4.0 pg/mL and had a sensitivity of 77.8%, a specificity of 99.6%, a positive predictive value of 98%, and a negative predictive value of 94.5%. On the other hand, the diagnostic accuracy of the antigen test decreased among patients among patients with COVID-19 with threshold cycle (Ct-value)≥27, which shows the AUROC was 0.795 (95%CI 0.687-0.907, p < 0.001). CONCLUSION: While the automated quantitative CLEIA antigen test from saliva specimen could be one of the most useful diagnostic tests for the diagnosis of COVID-19 in general practice, clinicians should know the limitations of the antigen test.

Comparative evaluation of nasopharyngeal swab and saliva specimens for the molecular detection of SARS-CoV-2 RNA in Japanese patients with COVID-19.

Considering the issues of shortage of medical resources and the invasiveness and infection risk involved in the collection of nasopharyngeal swab specimens, there is a need for an effective alternative test specimen for SARS-CoV-2 RNA detection. Here, we investigated suitability of saliva as a non-invasively obtained specimen for molecular detection of SARS-CoV-2 RNA in Japanese patients with COVID-19. In total, 28 paired clinical specimens of saliva and nasopharyngeal swabs were collected from 12 patients at various time points after symptom onset. Each specimen was assayed using reverse transcription real-time polymerase chain reaction (rRT-PCR) on the BD MAX open system using primers and probes targeting the N-gene. The saliva and nasopharyngeal swab specimens showed 19 and 15 positive results, respectively. No invalid (PCR inhibition) result was observed for any specimen. The qualitative results of each specimen obtained in the period immediately after symptom onset were similar. Three convalescent patients presented saliva-positive results, whereas their nasopharyngeal swabs were negative at four different time points, suggesting that saliva may be superior to nasopharyngeal swabs in terms of obtaining stable assay result of SARS-CoV-2. In conclusion, our results suggest that saliva can potentially serve as an alternative to nasopharyngeal swabs as a specimen for SARS-CoV-2 rRT-PCR. As saliva can be collected by patients themselves, it may be an effective way to overcome the shortage of personal protective equipment and specimen sampling tools.

Clinical manifestations and radiological features by chest computed tomographic findings of a novel coronavirus disease-19 pneumonia among 92 patients in Japan.

INTRODUCTION: The novel coronavirus disease (COVID-19) could cause a severe acute respiratory infectious disease, showing a high mortality rate of 12-45% among cases who required intensive care unit admission. COVID-19 pneumonia PATIENTS AND METHODS: For the purpose of identifying clinical manifestations and radiological findings of COVID-19 pneumonia, we reviewed all cases of COVID-19 pneumonia which were published by the homepage of the Japanese Association for Infectious Diseases from Feb 5 2020 until April 30 2020, including our cases. All patients were diagnosed based on positive results of the novel coronavirus-real-time RT-PCR with chest computed tomography (CT) findings. RESULTS: A total of 92 patients were enrolled in this study. The median age was 66 years (range 16-92 years). For all, 50 (54%) were males. The most common underlying disease was hypertension in 32 (36%). Any comorbidity was seen in 60 (67%). The mortality rate was 4 (6%). In terms of clinical symptoms on an initial visit, fever and cough were confirmed in 66 (72%) and 37 (40%). Forty-three (47%) had no respiratory symptoms. As for radiological findings by chest CT scan, ground-glass opacities (GGO)s, peripheral distribution, bilateral lung involvements were seen in 88 (96%), 76 (83%) and 78 (85%), respectively. CONCLUSION: It is difficult to diagnose as COVID-19 pneumonia due to poor respiratory symptoms. Chest CT findings typically show GGO, peripheral and bilateral shadows. Patients should have chest CT performed if suspected for early diagnosis and therapeutic intervention, resulting in a favorable outcome and prevention of secondary nosocomial transmitted infection.

Could threshold cycle value correctly reflect the severity of novel coronavirus disease 2019 (COVID-19)?

The novel coronavirus disease 2019 (COVID-19) is diagnosed by positive result of reverse transcription polymerase chain reaction (RT-PCR) for the novel coronavirus. We concluded that cycle threshold value (Ct-value) of real-time RT-PCR (rRT-PCR) assay could decrease as patients recover. Results of rRT-PCR assay could remain positive among asymptomatic patients for longer than 2 weeks. The discharge criteria of COVID-19 patients using a negative result of rRT-PCR should be reconsidered.