Emergence and clonal expansion of Aeromonas hydrophila ST1172 that simultaneously produces MOX-13 and OXA-724.

BACKGROUND: Aeromonas hydrophila infections can cause gastrointestinal symptoms such as diarrhea; however, deep infections are rarely reported. Outbreaks of A. hydrophila are reported more frequently in fish, poultry, and snakes than in humans. This study aimed to track clonal relatedness of deep infections caused by A. hydrophila using whole genome sequencing (WGS). METHODS: We collected three isolates of A. hydrophila in July 19 to August 29, 2019, from patients that underwent spine surgery. Accurate species identification was performed using whole-genome average nucleotide identity (ANI). Antimicrobial susceptibility testing was performed using a VITEK 2 automated AST-N334 Gram-negative susceptibility card system. Antimicrobial resistance and virulence genes were identified using the Comprehensive Antibiotic Resistance Database and Virulence Factor Database VFanalyzer. RESULTS: All three isolates were identified as A. hydrophila based on ANI and multilocus sequence typing analysis revealed that A. hydrophila belonged to a novel sequence type (ST1172). All three isolates were susceptible to amikacin and levofloxacin; however, they were resistant to piperacillin/tazobactam, ceftriaxone, cefuroxime, cefoxitin, and imipenem. Isolate 19W05620 (patient 3) showed increased ceftazidime resistance (minimum inhibitory concentration ≥ 64 µg/mL). All three isolates possessed the same chromosomally encoded ß-lactamases, including blaOXA-724 (ß-lactamase), imiH (metallo-ß-lactamase), and blaMOX-13 (AmpC) in plasmids. CONCLUSIONS: Our study validated the transmission of a novel carbapenem-resistant A. hydrophila sequence type (ST1172) in patients that underwent spine surgery. Control measures should be developed to prevent dissemination of A. hydrophila in the hospital setting.

Combination Therapy of Ceftazidime/Avibactam for the Treatment of Patients Infected with Carbapenem-Resistant Klebsiella pneumoniae: A Multicenter Retrospective Study.

INTRODUCTION: This study aimed to evaluate the different efficacies between monotherapy and combination therapy with ceftazidime/avibactam (CAZ/AVI) in treating carbapenem-resistant Klebsiella pneumoniae (CRKP) infection. METHODS: We retrospectively analyzed observational multicenter data from 38 hospitals in China. Multivariate regression analysis was used to explore the association between combination therapy with CAZ/AVI and in-hospital mortality. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to validate our findings. RESULTS: A total of 132 eligible patients were divided into CAZ/AVI combination therapy (n = 43) and monotherapy (n = 89) cohorts. Multivariate logistic regression showed that there was no statistically significant relationship between combination therapy and a lower risk of in-hospital mortality [odds ratio (OR) 0.907, 95% confidence interval (CI) 0.329-2.498, p = 0.850]. In the subgroup of critical patients who were in the intensive care unit (ICU) (OR 0.943, 95% CI 0.221-4.033, p = 0.937) or with sequential organ failure assessment (SOFA) ≥ 3 (OR 0.733, 95% CI 0.191-2.808, p = 0.650), CAZ/AVI combination therapy was not a lower risk factor for in-hospital mortality. Moreover, in the subgroup of patients using CAZ/AVI plus tigecycline (accounting for 46.5% in the combination therapy) compared with CAZ/AVI monotherapy, there was no statistical difference between the two groups in in-hospital mortality, nor in the subgroup of patients with CRKP-associated pneumonia. CONCLUSION: Combination therapy (or CAZ/AVI combined with tigecycline) and monotherapy with CAZ/AVI had similar prognoses in patients with only CRKP infection (or CRKP-associated pneumonia), as well as in critically ill patients. Larger randomized controlled trials are warranted to confirm these findings.

Decreased echinocandin susceptibility in Candida parapsilosis causing candidemia and emergence of a pan-echinocandin resistant case in China.

Candida parapsilosis is becoming a predominant non-albicans cause of invasive candidiasis (IC). Echinocandins are the preferred choice for IC treatment and prophylaxis. Resistance to echinocandins in C. parapsilosis has emerged in several countries, but little is known about the susceptibility profile in China or about mechanisms of resistance. Here, we investigated the echinocandin susceptibilities of 2523 C. parapsilosis isolates collected from China and further explored the resistance mechanism among echinocandin-resistant isolates. Anidulafungin exhibited the highest MICs (MIC50/90, 1 and 2 µg/mL; GM, 0.948 µg/mL), while caspofungin showed better activity (0.5 and 1 µg/mL; 0.498 µg/mL). Significantly higher echinocandin MICs were observed among blood-derived isolates compared to others, especially for caspofungin (GM, 1.348 µg/mL vs 0.478 µg/mL). Isolates from ICU and surgical wards also showed higher MICs. Twenty isolates showed intermediate phenotypes for at least one echinocandin. One was resistant to all three echinocandins, fluconazole and voriconazole, which caused breakthrough IC during long-term exposure to micafungin. WGS revealed this isolate carried a mutation S656P in hotspot1 region of Fks1. Bioinformatics analyses suggested that this mutation might lead to an altered protein conformation. CRISPR Cas9-mediated introduction of this mutation into a susceptible reference C. parapsilosis strain increased MICs of all echinocandins 64-fold, with similar results found in the subspecies, C. orthopsilosis and C. metapsilosis. This is the first report of a multi-azole resistant and pan-echinocandin resistant C. parapsilosis isolate, and the identification of a FKS1S656P conferring pan-echinocandin resistance. Our study underscores the necessity of rigorous management of antifungal use and of monitoring for antifungal susceptibility.

De-escalation from Echinocandins to Azole Treatment in Critically Ill Patients with Candidemia.

OBJECTIVES: This study aims to further explore the duration of echinocandins and analyze the de-escalation (DE) strategy in patients with candidemia. METHODS: Multivariable logistic regression was used to evaluate the association between the duration of echinocandins (≤ 5-day group vs > 5-day group) and in-hospital mortality. RESULTS: Of the 357 cases of candidemia, 200 patients (56.02%) were identified in the ≤5-day group. The ≤5-day group did not have a higher in-hospital mortality than the >5-day group in the multivariable model (odds ratio [OR] 1.536, 95% confidence interval (CI) 0.837-2.819, P-value = 0.166), and the finding was validated by the propensity score matching and inverse probability of treatment weighting models. Subgroup analyses showed that patients in the ≤5-day group without DE may have a poor prognosis (OR 4.223, 95% CI 1.773-10.055, P-value = 0.001). The patients in the ≤5-day group, with a sequential organ failure assessment (SOFA) score of ≥3 evaluated at the time of stopping echinocandins, may have a poor prognosis (OR 2.164, 95% CI 1.009-4.641, P-value = 0.047). CONCLUSION: In critically ill adult patients with candidemia, the ≤5-day group with DE was feasible. However, the SOFA score was recommended when stopping echinocandins to ensure the safety of DE therapy.

Dynamic landscape mapping of humoral immunity to SARS-CoV-2 identifies non-structural protein antibodies associated with the survival of critical COVID-19 patients.

A comprehensive analysis of the humoral immune response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential in understanding COVID-19 pathogenesis and developing antibody-based diagnostics and therapy. In this work, we performed a longitudinal analysis of antibody responses to SARS-CoV-2 proteins in 104 serum samples from 49 critical COVID-19 patients using a peptide-based SARS-CoV-2 proteome microarray. Our data show that the binding epitopes of IgM and IgG antibodies differ across SARS-CoV-2 proteins and even within the same protein. Moreover, most IgM and IgG epitopes are located within nonstructural proteins (nsps), which are critical in inactivating the host's innate immune response and enabling SARS-CoV-2 replication, transcription, and polyprotein processing. IgM antibodies are associated with a good prognosis and target nsp3 and nsp5 proteases, whereas IgG antibodies are associated with high mortality and target structural proteins (Nucleocapsid, Spike, ORF3a). The epitopes targeted by antibodies in patients with a high mortality rate were further validated using an independent serum cohort (n = 56) and using global correlation mapping analysis with the clinical variables that are associated with COVID-19 severity. Our data provide fundamental insight into humoral immunity during SARS-CoV-2 infection. SARS-CoV-2 immunogenic epitopes identified in this work could also help direct antibody-based COVID-19 treatment and triage patients.

The seroprevalence and kinetics of IgM and IgG in the progression of COVID-19.

BACKGROUND: SARS-CoV-2 is a novel coronavirus first recognized in late December 2019 that causes coronavirus disease 19 (COVID-19). Due to the highly contagious nature of SARS-CoV-2, it has developed into a global pandemic in just a few months. Antibody testing is an effective method to supplement the diagnosis of COVID-19. However, multicentre studies are lacking to support the understanding of the seroprevalence and kinetics of SARS-CoV-2 antibodies in COVID-19 epidemic regions. METHOD: A multicentre cross-sectional study of suspected and confirmed patients from 4 epidemic cities in China and a cohort study of consecutive follow-up patients were conducted from 29/01/2020 to 12/03/2020. IgM and IgG antibodies elicited by SARS-CoV-2 were tested by a chemiluminescence assay. Clinical information, including basic demographic data, clinical classification, and time interval from onset to sampling, was collected from each centre. RESULTS: A total of 571 patients were enrolled in the cross-sectional study, including 235 COVID-19 patients and 336 suspected patients, each with 91.9%:2.1% seroprevalence of SARS-CoV-2 IgG and 92.3%:5.4% seroprevalence of SARS-CoV-2 IgM. The seroprevalence of SARS-CoV-2 IgM and IgG in COVID-19 patients was over 70% less than 7 days after symptom onset. Thirty COVID-19 patients were enrolled in the cohort study and followed up for 20 days. The peak concentrations of IgM and IgG were reached on the 10th and 20th days, respectively, after symptom onset. The seroprevalence of COVID-19 IgG and IgM increased along with the clinical classification and treatment time delay. CONCLUSION: We demonstrated the kinetics of IgM and IgG SARS-CoV-2 antibodies in COVID-19 patients and the association between clinical classification and antibodies, which will contribute to the interpretation of IgM and IgG SARS-CoV-2 antibody tests and in predicting the outcomes of patients with COVID-19.

Rapid diagnosis of Talaromyces marneffei infection assisted by metagenomic next-generation sequencing in a HIV-negative patient.

Talaromyces marneffei (T. marneffei), is an opportunistic pathogenic fungus commonly reported in southeast Asia. T. marneffei infection predominantly occurs in patients with immunodeficiency and can be fatal if diagnosis and treatment were delayed. Conventional diagnosis of T. marneffei infection relies heavily on tissue culture and histologic analysis, which is time consuming and has limited positive rate. Rapid and accurate diagnosis of T. marneffei remains urgent for effective therapy and prevention. This case is the first reported T. marneffei infection in non-HIV patients in north China diagnosed by mNGS. The successful diagnosis of T. marneffei infection assistant by mNGS underlies the potential of this technique in rapid etiological diagnosis.

Factors associated with inpatient length of stay among hospitalised patients with chronic obstructive pulmonary disease, China, 2016-2017: a retrospective study.

OBJECTIVES: To identify factors associated with length of stay (LOS) in chronic obstructive pulmonary disease (COPD) hospitalised patients, which may help shorten LOS and reduce economic burden accrued over hospital stay. DESIGN: A retrospective cohort study. SETTING: This study was performed in a tertiary hospital in China. PARTICIPANTS: Patients with COPD who were aged ≥40 years and newly admitted between 2016 and 2017. PRIMARY AND SECONDARY OUTCOME MEASURES: LOS at initial admission was the primary outcome and health expenditures were the secondary outcome. To identify factors associated with LOS, we collected information at index hospitalisation and constructed a conceptual model using directed acyclic graph. Potential factors were classified into five groups: demographic information, disease severity, comorbidities, hospital admission and environmental factors. Negative binomial regression model was fitted for each block of factors and a parsimonious analysis was performed. RESULTS: In total, we analysed 565 patients with COPD. The mean age was 69±11 years old and 69.4% were men. The median LOS was 10 (interquartile range 8-14) days. LOS was significantly longer in patients with venous thromboembolism (VTE) (16 vs 10 days, p=0.0002) or with osteoporosis (15 vs 10 days, p=0.0228). VTE ((rate ratio) RR 1.38, 95% CI 1.07 to 1.76), hypoxic-hypercarbic encephalopathy (RR 1.53, 95% CI 1.06 to 2.20), respiratory infection (RR 1.12, 95% CI 1.01 to 1.24), osteoporosis (RR 1.45, 95% CI 1.07 to 1.96) and emergence admission (RR 1.08, 95% CI 1.01 to 1.16) were associated with longer LOS. In parsimonious analysis, all these factors remained significant except emergency admission, highlighting the important role of concomitant morbidities in patients' hospital stay. Total hospitalisation cost and patients' out-of-pocket cost increased monotonically with LOS (both ptrend <0.0001). CONCLUSION: Patients' concomitant morbidities predicted excessive LOS in patients with COPD. Healthcare cost increased over the LOS. Quality improvement initiatives may need to identify patients at high risk for lengthy stay and implement early interventions to reduce COPD economic burden.

Serum Protein Profiling Reveals a Landscape of Inflammation and Immune Signaling in Early-stage COVID-19 Infection.

Coronavirus disease 2019 (COVID-19) is a highly contagious infection and threating the human lives in the world. The elevation of cytokines in blood is crucial to induce cytokine storm and immunosuppression in the transition of severity in COVID-19 patients. However, the comprehensive changes of serum proteins in COVID-19 patients throughout the SARS-CoV-2 infection is unknown. In this work, we developed a high-density antibody microarray and performed an in-depth proteomics analysis of serum samples collected from early COVID-19 (n = 15) and influenza (n = 13) patients. We identified a large set of differentially expressed proteins (n = 132) that participate in a landscape of inflammation and immune signaling related to the SARS-CoV-2 infection. Furthermore, the significant correlations of neutrophil and lymphocyte with the CCL2 and CXCL10 mediated cytokine signaling pathways was identified. These information are valuable for the understanding of COVID-19 pathogenesis, identification of biomarkers and development of the optimal anti-inflammation therapy.

Antiphospholipid Antibodies in Critically Ill Patients With COVID-19.

OBJECTIVE: Coagulopathy is one of the characteristics observed in critically ill patients with coronavirus disease 2019 (COVID-19). Antiphospholipid antibodies (aPLs) contribute to coagulopathy, though their role in COVID-19 remains unclear. This study was undertaken to determine the prevalence and characteristics of aPLs in patients with COVID-19. METHODS: Sera collected from 66 COVID-19 patients who were critically ill and 13 COVID-19 patients who were not critically ill were tested by chemiluminescence immunoassay for anticardiolipin antibodies (aCLs), anti-ß2 -glycoprotein I (anti-ß2 GPI) (IgG, IgM, and IgA), and IgG anti-ß2 GPI-domain 1 (anti-ß2 GPI-D1) and IgM and IgG anti-phosphatidylserine/prothrombin (anti-PS/PT) antibodies were detected in the serum by enzyme-linked immunosorbent assay. RESULTS: Of the 66 COVID-19 patients in critical condition, aPLs were detected in 31 (47% ). Antiphospholipid antibodies were not present among COVID-19 patients who were not in critical condition. The IgA anti-ß2 GPI antibody was the most commonly observed aPL in patients with COVID-19 and was present in 28.8% (19 of 66) of the critically ill patients, followed by IgA aCLs (17 of 66, or 25.8%) and IgG anti-ß2 GPI (12 of 66, or 18.2%). For multiple aPLs, IgA anti-ß2 GPI + IgA aCLs was the most common antibody profile observed (15 of 66, or 22.7%), followed by IgA anti-ß2 GPI + IgA aCL + IgG anti-ß2 GPI (10 of 66, or 15.2%). Antiphospholipid antibodies emerge ~35-39 days after disease onset. A dynamic analysis of aPLs revealed 4 patterns based on the persistence or transient appearance of the aPLs. Patients with multiple aPLs had a significantly higher incidence of cerebral infarction compared to patients who were negative for aPLs (P = 0.023). CONCLUSION: Antiphospholipid antibodies were common in critically ill patients with COVID-19. Repeated testing demonstrating medium to high titers of aPLs and the number of aPL types a patient is positive for may help in identifying patients who are at risk of developing cerebral infarction. Antiphospholipid antibodies may be transient and disappear within a few weeks, but in genetically predisposed patients, COVID-19 may trigger the development of an autoimmune condition similar to the antiphospholipid syndrome (APS), referred to as "COVID-19-induced APS-like syndrome." Long-term follow-up of COVID-19 patients who are positive for aPLs would be of great importance in understanding the pathogenesis of this novel coronavirus.

Molecular Characterization of Candida parapsilosis by Microsatellite Typing and Emergence of Clonal Antifungal Drug Resistant Strains in a Multicenter Surveillance in China.

Candida parapsilosis is an important species causing invasive candidiasis (IC) in China. The present survey was a national multicenter study of the molecular epidemiology and antifungal susceptibility profiles of C. parapsilosis. Non-duplicate C. parapsilosis isolates were collected from 10 hospitals across China in the CHIF-NET program 2016-2017. Isolates were genotyped using four highly polymorphic microsatellite markers, and susceptibility profiles determined using Sensititre YeastOneTM YO10. A total of 319 C. parapsilosis from separate patients with IC were studied; 49.2, 17.9, and 10.3% isolates were from patients in surgical departments, general intensive care units (ICUs) and neonatal ICUs (NICU), respectively. C. parapsilosis showed good susceptibility to nine antifungal drugs. Microsatellite analysis identified 122 microsatellite (MT) types. Most MT types had sporadic distribution. However, we identified 32 clusters across 10 hospitals; seven clusters were caused by seven endemic genotypes involving five or more isolates in hospitals designated as H01, H02, H06, and H10. These clusters mainly affected surgical departments and ICUs, except for genotype MT42 which was seen in 22 patients from NICU (hospital H06). Of 16 fluconazole-resistant isolates, seven from hospital H02 shared the same genotype MT70, and three from hospital H04 were of genotype MT47. For 37 isolates with non-wild type MICs to 5-flucytosine, 29 were from hospital H01 (genotype MT48). Here we present the first nationwide molecular epidemiology study of C. parapsilosis in China, identified several previously unrecognized clusters, which included antifungal drug resistant isolates. These findings provide important data for control of IC in China.

Recommendation for the diagnosis and management of immune checkpoint inhibitor related infections.

Immune checkpoint inhibitors (ICIs) have been widely used in the management of malignant tumors. Programmed death 1 (PD-1)/PD-1 ligand (PD-L1) inhibitors have been introduced to treat non-small cell lung cancer (NSCLC) in recent years. Currently, PD-1/PD-L1 inhibitors are considered to have minor side effects and do not independently increase the risk of infection. However, they may cause immune-related adverse events (irAEs) that require immunosuppressive therapy with corticosteroids and/or immunosuppressants, leading to opportunistic infections. Furthermore, there have been reports describing reactivation of chronic/latent infections without irAEs or having received immunosuppressants. Thus, immune checkpoint inhibitor related infections have received more attention worldwide. In this paper, we review available clinical data, describe the potential mechanism, and propose recommendations for the diagnosis and clinical management of PD-1/PD-L1 inhibitor-related infections.

[Recommendation of Diagnosis and Management for the Infections Related to Immune Checkpoint Inhibitors].

Immune checkpoint inhibitors (ICIs) have been widely used in management of malignant tumor. Programmed death ligand 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors have been introduced to treat non-small cell lung cancer (NSCLC) in recent years. Currently, PD-1/PD-L1 inhibitors are considered to have minor side effects and do not independently increase the risk of infection. However, they may cause immune-related adverse events (irAEs) that can require immunosuppressive therapy with corticosteroids and/or immunosuppressants, leading to opportunistic infections. Furthermore, there were reports about reactivation of chronic/latent infections without irAEs. Thus, immune checkpoint inhibitor related infections have drawn more and more attention in the world. In this paper, we described the potential mechanism, available clinical data and recommendation of diagnosis and management for PD-1/PD-L1 inhibitor related infections.

Association of RAGE gene multiple variants with the risk for COPD and asthma in northern Han Chinese.

Clinical and experimental data have shown that the receptor for advanced glycation end products (RAGE) is implicated in the pathogenesis of respiratory disorders. In this study, we genotyped five widely-evaluated variants in RAGE gene, aiming to assess their association with the risk for chronic obstructive pulmonary disease (COPD) and asthma in northern Han Chinese. Genotypes were determined in 105 COPD patients, 242 asthma patients and 527 controls. In single-locus analysis, there was significant difference in the genotype distributions of rs1800624 between COPD patients and controls (p=0.022), and the genotype and allele distributions of rs1800625 differed significantly (p=0.040 and 0.016) between asthma patients and controls. Haplotype analysis revealed that haplotype T-A-G-T (allele order: rs1800625, rs1800624, rs2070600, rs184003) was significantly associated with a reduced COPD risk (OR=0.32, 95% CI: 0.06-0.60), and haplotype T-A-A-G was significantly associated with a reduced asthma risk (OR=0.19, 95% CI: 0.04-0.96). Further haplotype-phenotype analysis showed that high- and low-density lipoprotein cholesterol and blood urea nitrogen were significant mediators for COPD (psim=0.041, 0.043 and 0.030, respectively), and total cholesterol was a significant mediator for asthma (psim=0.009). Taken together, our findings indicate that RAGE gene is a promising candidate for COPD and asthma, and importantly both disorders are genetically heterogeneous.