Antivirals for Coexistence with COVID-19: Brief Review for General Physicians.

In order to end the coronavirus disease 2019 (COVID-19) pandemic that has lasted for nearly two years, it is most necessary to introduce antiviral drugs specific to COVID-19 along with the establishment of herd immunity by vaccination. Candidates currently being studied include nucleoside analogues that inhibit replication, protease inhibitors, and entry blockers. Not only the virus itself, but also the host protein that the virus uses in its pathogenesis is the target of treatment. Although the severe acute respiratory syndrome coronavirus 2 will not be completely eradicated, if the use of antiviral drugs is established, the COVID-19 pandemic will end through coexistence with the virus.

What We Do Know and Do Not Yet Know about COVID-19 Vaccines as of the Beginning of the Year 2021.

Coronavirus disease 2019 (COVID-19), which started at the end of 2019 and has spread worldwide, has remained unabated in 2021. Since non-pharmaceutical interventions including social distancing are facing limitations in controlling COVID-19, additional absolute means to change the trend are necessary. To this end, coronavirus-specific antiviral drugs and vaccines are urgently needed, but for now, the priority is to promote herd immunity through extensive nationwide vaccination campaign. In addition to the vaccines based on the conventional technology such inactivated or killed virus or protein subunit vaccines, several vaccines on the new technological platforms, for example, nucleic acids-based vaccines delivered by viral carriers, nanoparticles, or plasmids as a medium were introduced in this pandemic. In addition to achieving sufficient herd immunity with vaccination, the development of antiviral treatments that work specifically against COVID-19 will also be necessary to terminate the epidemic completely.

Analysis of PubMed and KoreaMed Indexed Korean Publications on COVID-19.

During the coronavirus disease 2019 (COVID-19) pandemic, publications on the disease have exploded globally. The present study analyzed PubMed and KoreaMed indexed COVID-19 publications by Korean researchers from January 1, 2020 to August 19, 2021. A total of 83,549 COVID-19 articles were recorded in PubMed and 1,875 of these were published by Korean authors in 673 journals (67 Korean and 606 overseas journals). The KoreaMed platform covered 766 articles on COVID-19, including 612 by Korean authors. Among the Journal of Korean Medical Science (JKMS) articles on COVID-19, PubMed covered 176 and KoreaMed 141 documents. Korean researchers contributed to 2.2% of global publications on COVID-19 in PubMed. The JKMS has published most articles on COVID-19 in Korea.

Intracerebral Hemorrhage due to Thrombosis with Thrombocytopenia Syndrome after Vaccination against COVID-19: the First Fatal Case in Korea.

Vaccination with an adenoviral vector vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can result in the rare development of thrombosis with thrombocytopenia mediated by platelet-activating antibodies against platelet factor 4 (PF4). This is a life-threating condition that may be accompanied by bleeding due to thrombocytopenia with thrombosis of the cerebral venous sinus or splanchnic vein. Herein, we describe the first fatal case of thrombosis with thrombocytopenia syndrome in Korea, presenting with intracranial hemorrhage caused by cerebral venous sinus thrombosis. A 33-year-old Korean man received the first dose of the ChAdOx1 nCoV-19 vaccination. He developed severe headache with vomiting 9 days after the vaccination. Twelve days after vaccination, he was admitted to the hospital with neurological symptoms and was diagnosed with cerebral venous sinus thrombosis, which was accompanied by intracranial hemorrhage. Thrombocytopenia and D-dimer elevation were observed, and the result of the PF4 enzyme-linked immunosorbent assay antibody test was reported to be strongly positive. Despite intensive treatment, including intravenous immunoglobulin injection and endovascular mechanical thrombectomy, the patient died 19 days after vaccination. Physicians need to be aware of thrombosis with thrombocytopenia syndrome (TTS) in adenoviral vector-vaccinated patients. Endovascular mechanical thrombectomy might be a useful therapeutic option for the treatment of TTS with cerebral venous sinus thrombosis.

Risk Factors of Outcomes of COVID-19 Patients in Korea: Focus on Early Symptoms.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has spread around the globe, and it is important to determine the risk factors of death in the general population. Our study aimed to determine the risk factors of death and severe illness requiring supplemental oxygen therapy based on the demographic and clinical characteristics of COVID-19 patients in Korea. METHODS: In this study, we used data provided by the Korea Disease Control and Prevention Agency (KDCA) and analyzed a total of 5,068 patients with COVID-19, excluding 19 pregnant women and 544 individuals with missing data. We performed logistic regression analysis to determine the impact of early symptoms on survival and severe disease. Logistic regression models included sex, age, number of comorbidities, symptoms on admission, blood pressure, heart rate, and body temperature as explanatory variables, and death and oxygen therapy as outcome variables. RESULTS: Logistic regression analyses revealed that the male sex, older age (≥ 60 years), higher number of comorbidities, presence of symptoms on admission, heart rate ≥ 120 bpm, and body temperature ≥ 37.5°C presented with higher risk of in-hospital death and oxygen therapy requirement. Conversely, rhinorrhea and headache were associated with a low risk of death and oxygen therapy requirement. The findings showed that cough, sputum, and fever were the most common symptoms on admission, while 25.3% of patients with COVID-19 were asymptomatic. CONCLUSION: COVID-19 patients with high-risk early symptoms on admission, such as dyspnea and altered mental status, and those without low-risk symptoms of rhinorrhea and headache should be included in priority treatment groups.

Epidemiology and Antifungal Susceptibility Profile of Aspergillus Species: Comparison between Environmental and Clinical Isolates from Patients with Hematologic Malignancies.

Global data on the epidemiology and susceptibility of Aspergillus are crucial in the management of invasive aspergillosis. Here, we aimed to determine the characteristics of clinical and environmental Aspergillus isolates, focusing mainly on hematologic malignancy patients. We prospectively collected all consecutive cases and clinical isolates of culture-positive proven/probable invasive aspergillosis patients from January 2016 to April 2018 and sampled the air inside and outside the hospital. Cryptic species-level identification of Aspergillus, antifungal susceptibilities, and cyp51 gene sequencing were performed, and clinical data were analyzed. This study was conducted as part of the Catholic Hematology Hospital Fungi Epidemiology (CAFÉ) study. A total of 207 proven/probable invasive aspergillosis and 102 clinical and 129 environmental Aspergillus isolates were included in this analysis. The incidence of proven/probable invasive aspergillosis was 1.3 cases/1,000 patient-days during the study period. Cryptic Aspergillus species accounted for 33.8%, with no differences in proportions between the clinical and environmental isolates. Section Nigri presented a high proportion (70.5%) of cryptic species, mainly from A. tubingensis and A. awamori: the former being dominant in environmental samples, and the latter being more common in clinical isolates (P < 0.001). Of 91 A. fumigatus isolates, azole-resistant A. fumigatus was found in 5.3% of all A. fumigatus isolates. Three isolates presented the TR34/L98H mutation of the cyp51A gene. Patients with invasive aspergillosis caused by azole-resistant A. fumigatus showed 100% all-cause mortality at 100 days. This study demonstrates the significant portion of cryptic Aspergillus species and clinical implications of azole resistance and underscores the comparison between clinical and environmental isolates.

Risk factors and clinical outcomes of breakthrough yeast bloodstream infections in patients with hematological malignancies in the era of newer antifungal agents.

Although yeast bloodstream infections (BSIs) are increasingly being reported in patients with hematological malignancies undergoing antifungal therapy, clinical information regarding breakthrough infections is scarce. The aim of this study was to determine the risk factors for and clinical outcomes of breakthrough yeast BSIs in patients with hematological malignancies in the era of newer antifungal agents. Between 2011 and 2014, all consecutive patients with hematological malignancies who developed yeast BSIs were included in a case-control study wherein breakthrough infections (cases) and de novo infections (controls) were compared. Of 49 patients with yeast BSIs, 21 (43%) met the criteria for breakthrough infections. The proportions of Candida krusei and Candida tropicalis in the cases and controls were significantly different (32% [7/22] vs. 3% [1/29], P = .015; 5% [1/22] vs. 38% [11/29], P = .007, respectively). Acute leukemia, presence of a central venous catheter and neutropenia in the 3 days prior to BSI were significant risk factors for breakthrough infections. Six-week mortality rates was 33% [7/21] in the cases and 43% [12/28] in the controls (P = .564). Refractory neutropenia and the Pitt bacteremia score were independent predictors of 6-week mortality. In conclusion, breakthrough infections accounted for a significant proportion of yeast BSIs in patients with hematological malignancies. However, these infections did not increase the risk of death by themselves. Our results suggest that current clinical management of breakthrough yeast BSIs, which includes switching to a different antifungal class and prompt catheter removal is reasonable.

The Infinity War: How to Cope with Carbapenem-resistant Enterobacteriaceae.

Carbapenem-resistant Enterobacteriaceae (CRE) are now spread worldwide. In Korea, the number of CRE isolation is rapidly increasing, and impending endemicity is a concern. To cope well with CRE, thorough infection control, such as active surveillance, early detection, strict contact precaution, cleaning the environment, and antibiotic stewardship is very important. Therapeutic options include polymyxin, tigecycline, fosfomycin or the combination of them with carbapenem, which is currently the mainstay of treatment. In addition, various combination regimens with new carbapenemase inhibitors such as avibactam, vaborbactam, or relebactam, and other classes of antimicrobials such as plazomicin and siderophore cephalosporin are in the process of evaluation.

Breakthrough invasive fungal diseases during voriconazole treatment for aspergillosis: A 5-year retrospective cohort study.

Breakthrough invasive fungal diseases (bIFDs) during voriconazole treatment are concerning, as they are associated with high rates of mortality and pathogen distribution. To evaluate the prevalence, incidence, patient characteristics, including IFD events, and overall mortality of bIFDs during voriconazole treatment for invasive aspergillosis (IA). We retrospectively analyzed the medical records of consecutive patients who had undergone voriconazole treatment for IA and who had bIFD events between January 2011 and December 2015. Eleven bIFD events occurred in 9 patients. The prevalence and incidence of bIFDs were 2.25% (9/368) and 0.22 cases per year, respectively. Overall mortality was 44.4% (4/9). The severity of the illness and persistence of immunodeficiency, mixed infection, and low concentration of the treatment drug at the site of infection were identified as possible causes of bIFDs. Seven of 11 events (63.6%) required continued voriconazole treatment with drug level monitoring. In 4 (36.3%) cases, the treatment was changed to liposomal amphotericin B. Two cases resulted in surgical resection (18.2%). Clinicians should be aware that bIFDs during voriconazole treatment for IA can occur, and active therapeutic approaches are required in these cases.

Immunomodulatory effect of mesenchymal stem cells on the immune response of macrophages stimulated by Aspergillus fumigatus conidia.

Mesenchymal stem cells (MSCs) are known to exert potent immunosuppression and anti-inflammatory effects. There is growing interest in their use for immunotherapy for controlling inflammation as well as acute organ injury. However, there are few reports regarding MSC's immunomodulatory effects in the settings of fungal infection. In this study, we attempted to examine the immunomodulatory effects of MSCs in response to Aspergillus fumigatus We measured the cytokine response of murine MSCs on the immune response of murine macrophages (J774A.1 cells) evoked by A. fumigatus conidia. In addition, we evaluated the effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) on the MSC-related cytokine response and fungal growth. As a results, after conidia stimulation, tumor necrosis factor (TNF)-α was down-regulated and interleukin (IL)-10 was up-regulated in MSC-treated J774A.1 cells when compared to J774A.1 cells alone. In addition, fungal growth was reduced in MSC-treated J774A.1 cells when compared to J774A.1 cells, which recovered by GM-CSF. However, the effect of MSCs on the cytokine response was not reversed by GM-CSF. NF-κB translocation decreased in MSC-treated J774A.1 cells compared to J774A.1 cells alone. In conclusion, MSCs demonstrate immunomodulatory properties in both aspects of cytokines and fungal growth. The anti-inflammatory effect of MSCs with regard to cytokine response might be associated with decreased NF-κB translocation, and is not reversed by GM-CSF.

Therapeutic drug monitoring and safety of intravenous voriconazole formulated with sulfobutylether ß-cyclodextrin in haematological patients with renal impairment.

Because of concerns about accumulation of cyclodextrin, oral voriconazole is recommended for patients with renal impairment. However, intravenous voriconazole may occasionally be imperative in critically ill patients with life-threatening invasive aspergillosis. We investigated the clinical effects of intravenous voriconazole formulated with sulfobutylether ß-cyclodextrin (SBECD) in patients with renal impairment. A prospective observational study was conducted on 25 adult patients with haematological malignancies who were treated with intravenous voriconazole for invasive aspergillosis. Among them, seven patients had a baseline creatinine clearance (CrCl) <50 ml min(-1) (case). Although voriconazole trough concentrations were significantly higher in cases (5.84 mg l(-1) ) than controls (2.28 mg l(-1) ), the proportion of concentrations within the target range did not differ between two groups (4/7 and 12/18, respectively; P = 0.658). The frequency of severe adverse events in cases (3/7) was comparable to that of controls (4/18; P = 0.355). No patients showed significant deterioration in renal function after the voriconazole therapy even in patients with renal impairment. Although CrCl <50 ml min(-1) was associated with higher voriconazole concentrations, its clinical impact remains unclear. SBECD-formulated intravenous voriconazole did not lead to a higher incidence of severe adverse events including nephrotoxicity in haematological patients with CrCl <50 ml min(-1) .

Impact of extended-spectrum ß-lactamase production on treatment outcomes of acute pyelonephritis caused by escherichia coli in patients without health care-associated risk factors.

Extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) is increasingly identified as a cause of acute pyelonephritis (APN) among patients without recent health care contact, i.e., community-associated APN. This case-control study compared 75 cases of community-associated ESBL-EC APN (CA-ESBL) to 225 controls of community-associated non-ESBL-EC APN (CA-non-ESBL) to identify the risk factors for ESBL-EC acquisition and investigate the impact of ESBL on the treatment outcomes of community-associated APN (CA-APN) caused by E. coli at a Korean hospital during 2007 to 2013. The baseline characteristics were similar between the cases and controls; the risk factors for ESBL-EC were age (>55 years), antibiotic use within the previous year, and diabetes with recurrent APN. The severity of illness did not differ between CA-ESBL and CA-non-ESBL (Acute Physiology and Chronic Health Evaluation [APACHE] II scores [mean ± standard deviation], 7.7 ± 5.9 versus 6.4 ± 5.3; P = 0.071). The proportions of clinical (odds ratio [OR], 1.76; 95% confidence interval [CI], 0.57 to 5.38; P = 0.323) and microbiological (OR, 1.16; 95% CI, 0.51 to 2.65; P = 0.730) cures were similar, although the CA-ESBL APN patients were less likely to receive appropriate antibiotics within 48 h. A multivariable Cox proportional hazards analysis of the prognostic factors for CA-APN caused by E. coli showed that ESBL production was not a significant factor for clinical (hazard ratio [HR], 0.39; 95% CI, 0.12 to 1.30; P = 0.126) or microbiological (HR, 0.49; 95% CI, 0.21 to 1.12; P = 0.091) failure. The estimates did not change after incorporating weights calculated using propensity scores for acquiring ESBL-EC. Therefore, ESBL production did not negatively affect treatment outcomes among patients with community-associated E. coli APN.

Stenotrophomonas maltophilia bloodstream infection in patients with hematologic malignancies: a retrospective study and in vitro activities of antimicrobial combinations.

BACKGROUND: Stenotrophomonas maltophilia causes serious infections in immunocompromised hosts. Here, we analyzed the clinical characteristics of S. maltophilia bloodstream infection (BSI) in patients with hematologic malignancies and evaluated in vitro synergistic effects of antimicrobial combinations. METHODS: We retrospectively reviewed all consecutive episodes of S. maltophilia BSIs in adult hematologic patients from June 2009 to May 2014, with in vitro susceptibility and synergy tests using high-throughput bioluminescence assay performed for available clinical isolates. RESULTS: Among 11,004 admissions during 5-year period, 31 cases were identified as S. maltophilia BSIs. The incidence rate of S. maltophilia BSI was 0.134 cases/1,000 patient-days. Overall and attributable mortality of S. maltophilia BSI was 64.5% and 38.7%, respectively. Severe neutropenia (adjusted hazard ratio [HR] 5.24, p =0.013), shock at the onset of BSI (adjusted HR 6.05, p <0.001), and pneumonia (adjusted HR 3.15, p =0.017) were independent risk factors for mortality. In vitro susceptibilities to ceftazidime, levofloxacin, ticarcillin-clavulanic acid (TIM) and trimethoprim-sulfamethoxazole (SXT) were 11.1%, 44.0%, 40.7%, and 88.9%, respectively. MIC50/MIC90 for moxifloxacin and tigecycline were 1/4 mg/L and 4/8 mg/L. The 50% and 90% fractional inhibitory concentrations (FIC(50)/FIC(90)) of clinical isolates against a combination of SXT and TIM were 0.500/0.750. For SXT plus levofloxacin or moxifloxacin, FIC(50)/FIC(90) were 0.625/1.000 and 0.625/0.625, respectively. CONCLUSION: S. maltophilia BSIs show high mortality, which is related to severe neutropenia, shock, and S. maltophilia pneumonia. Based upon drug susceptibility testing, the primary treatment of choice for S. maltophilia BSIs should be SXT in hematologic patients, rather than quinolones, with combination therapies including SXT serving as a feasible treatment option.