Rapid antigen tests (RATs) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have advantages over viral culture in terms of cost and rapidity of testing, but they have low sensitivity. ...In addition, RATs tend to be negative from approximately 11 days after symptom onset. To determine whether the antigen-negative state indicates a lack of infectiousness, we assessed the association between viral culture and RAT results. Viral culture, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and rapid antigen testing were performed on stored nasopharyngeal samples with threshold cycle values < 30, based on previous RT-qPCR testing. SARS-CoV-2 was isolated by viral culture from nine samples (45%) and one sample (17%) with positive and negative RAT results, respectively. The RAT and viral culture results were both associated with the viral load level and their cutoffs were similar, but the associations were not statistically significant. RAT might be a useful indicator of infectiousness, which can be helpful to control infection. However, further studies with larger sample size are warranted to confirm this observation.
During an earlier multicenter, open-label, randomized controlled trial designed to evaluate the effectiveness of high-dose inhaled ciclesonide in patients with asymptomatic or mild coronavirus ...disease 2019 (COVID-19), we observed that worsening of shadows on CT without worsening of clinical symptoms was more common with ciclesonide. The present study sought to determine if an association exists between worsening CT shadows and impaired antibody production in patients treated with inhaled ciclesonide. Eighty-nine of the 90 patients in the original study were prospectively enrolled. After exclusions, there were 36 patients each in the ciclesonide and control groups. We analyzed antibody titers against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein at various time points. Changes in viral load during treatment were compared. There was no significant difference in age, sex, body mass index, background clinical characteristics, or symptoms between the two groups. Although evaluation on day 8 suggested a greater tendency for worsening shadows on CT in the ciclesonide group (p = 0.072), there was no significant difference between them in the ability to produce antibodies (p = 0.379) or the maximum antibody titer during the clinical course. In both groups, worsening CT shadows and higher viral loads were observed on days 1-8, suggesting ciclesonide does not affect clearance of the virus (p = 0.134). High-dose inhaled ciclesonide did not impair production of antibodies against SARS-CoV-2 or affect elimination of the virus, suggesting that this treatment can be used safely in patients with COVID-19 patients who use inhaled steroids for asthma and other diseases.
The detection of other pathogens in patients with hospitalized coronavirus disease (COVID-19) are not frequent. Considering that data from Japan are limited, we conducted an observational study ...including patients with hospitalized COVID-19 at the National Center for Global Health and Medicine from January to September 2020. In total, 247 patients with COVID-19 were included in the study. Rapid diagnostic tests, such as immunochromatography, were performed in 31 patients (12.6%). The Film Array Respiratory Panel was performed in 18 (7.3%) patients, and none of the tests were positive for pathogens other than severe acute respiratory syndrome coronavirus 2. Respiratory bacterial culture was performed in 66 (26.7%) patients, with gram-positive bacteria, gram-negative bacteria and normal flora being detected in eight (12.1%), seven (10.6%), and 63 (95.5%) patients, respectively. Patients for whom cultures were performed were older, more severely ill, and more likely to have radiological evidence of pneumonia on admission. Culture was performed more frequently in the early than in the later period of the epidemic, without any differences being observed in bacterial detection rates. The proportion of viral and bacterial detection among hospitalized patients with COVID-19 in tertiary care hospitals in Japan was low. A larger cohort study is necessary to evaluate the effect of each pathogen on the clinical course of COVID-19.
High-flow nasal cannula (HFNC) can be effective in treating type 1 respiratory failure by reducing the severity of coronavirus disease 2019 (COVID-19). The purpose of this study was to assess the ...reduction of disease severity and safety of HFNC treatment in patients with severe COVID-19. We retrospectively observed 513 consecutive patients with COVID-19 admitted to our hospital from January 2020 to January 2021. We included patients with severe COVID-19 who received HFNC for their deteriorating respiratory status. HFNC success was defined as improvement in respiratory status after HFNC and transfer to conventional oxygen therapy, while HFNC failure was defined as transfer to non‐invasive positive pressure ventilation or ventilator, or death after HFNC. Predictive factors associated with failure to prevent severe disease were identified. Thirty-eight patients received HFNC. Twenty-five (65.8%) patients were classified in the HFNC success group. In the univariate analysis, age, history of chronic kidney disease (CKD), non-respiratory sequential organ failure assessment (SOFA) ≥ 1, oxygen saturation to fraction of inspired oxygen ratio (SpO2/FiO2) before HFNC ≤ 169.2, were significant predictors of HFNC failure. Multivariate analysis revealed that SpO2/FiO2 value before HFNC ≤ 169.2 was an independent predictor of HFNC failure. No apparent nosocomial infection occurred during the study period. Appropriate use of HFNC for acute respiratory failure caused by COVID-19 can reduce the severity of severe disease without causing nosocomial infection. Age, history of CKD, non-respiratory SOFA before HFNC ≤ 1, and SpO2/FiO2 before HFNC ≤ 169.2 were associated with HFNC failure.
Seasonal influenza virus causes acute respiratory tract infections, which can be severe in children and the elderly. At present, rapid influenza diagnostic tests (RIDTs) are popular at clinical sites ...because they enable early diagnosis and avoid unnecessary use of antibiotics; in addition, high risk patients with underlying disease can be given antiviral drugs. However, the sensitivity and specificity of some of those tests are relatively poor. To overcome these problems, nucleic acid-based molecular point-of-care tests have been developed; however, they are significantly more expensive than RIDTs. Previously, the authors developed real-time reverse transcription loop-mediated isothermal amplification (rRT-LAMP) assays using a quenching primer to detect influenza viruses. However, the assay is limited to laboratory use because it requires a nucleic acid purification step and preparation of reaction mixtures on ice. Therefore, the authors developed and validated direct rRT-LAMP assays that require no nucleic acid purification steps using commercial RNA isolation kits, and no storage and handling of reagents on ice. These assays can be performed within 10–30 min and require only mixing a clinical specimen with extraction reagent followed by addition of a lyophilized detection reagent. The established assay showed high sensitivity and specificity when validated using 310 clinical specimens. Thus, the assay is a powerful tool for molecular diagnosis of seasonal influenza virus infection in the clinic.
The reverse transcription polymerase chain reaction (RT-PCR) offers high sensitivity, but has some drawbacks, such as the time required for the RNA extraction. Transcription reverse-transcription ...concerted reaction (TRC) Ready® SARS-CoV-2 i is easy to use and can be performed in about 40 minutes. TRC Ready® SARS-CoV-2 i and real-time one-step RT-PCR using the TaqMan probe tests of cryopreserved nasopharyngeal swab samples from patients diagnosed with COVID-19 were compared. The primary objective was to examine the positive and negative concordance rates. A total of 69 samples cryopreserved at -80° C were examined. Of the 37 frozen samples that were expected to be RT-PCR positive, 35 were positive by the RT-PCR method. TRC Ready® SARS-CoV-2 i detected 33 positive cases and 2 negative cases. One frozen sample that was expected to be RT-PCR positive was negative on both TRC Ready® SARS-CoV-2 i and RT-PCR. In addition, one frozen sample that was expected to be RT-PCR positive was positive by the RT-PCR method and negative by TRC Ready® SARS-CoV-2 i. Of the 32 frozen samples that were expected to be RT-PCR negative, both the RT-PCR method and TRC Ready® SARS-CoV-2 i yielded negative results for all 32 samples. Compared with RT-PCR, TRC Ready® SARS-CoV-2 i had a positive concordance rate of 94.3% and a negative concordance rate of 97.1%. TRC Ready® SARS-CoV-2 i can be utilized in a wide range of medical sites such as clinics and community hospitals due to its ease of operability, and is expected to be useful in infection control.
Anti-tumor necrosis factor α (anti-TNFα) agents increase the risk of tuberculosis (TB), but cases are rarely fatal. This report concerns a patient who was undergoing treatment with infliximab and ...presented with acute respiratory distress syndrome due to miliary TB without a miliary shadow. The findings of a pathological autopsy revealed innumerable granulomas in the organs, and the miliary nodules in the lung consisted of more unstructured granulomas. Anti-TNFα agents are unusual in the presentation of TB. It is important, particularly for patients receiving anti-TNFα agents, to constantly consider the possibility of TB and to prepare for appropriate management.
A 63-year-old man was transferred to our hospital because of an exacerbation of asthma. His symptoms deteriorated even after increasing the dose of inhaled corticosteroids/long-acting ...beta2-adrenoceptor agonists (ICS/LABA). He had no chest pain and an electrocardiogram revealed ST elevation. A coronary angiogram revealed a reduced left ventricular function with an apical ballooning pattern without coronary stenosis. He was diagnosed with Takotsubo cardiomyopathy. Catecholamine elevation due to acute asthma and an overdose of ICS/LABA may be triggers of this disease. We should remember that Takotsubo cardiomyopathy is a complication of asthma and that catecholamine plays an important role in its onset, although it is essential for asthma treatment.
Nontuberculous mycobacterial bone infections among human immunodeficiency virus (HIV)-negative patients are rare, although a few studies have described such infections. We retrospectively reviewed ...the medical and microbiological data of HIV-negative osteomyelitis cases caused by nontuberculous mycobacteria treated in our tertiary-care hospital over 14 years from January 1, 2000, to December 31, 2013. Three HIV-negative patients had contracted bone infections due to nontuberculous mycobacteria. All of the patients had at least 1 predisposing condition that led to the infections: idiopathic CD4-positive lymphocytopenia and/or anti-interferon-γ autoantibody syndrome.
PDF
