Prognostic Significance of NLR and PLR in COVID-19: A Multi-Cohort Validation Study.

INTRODUCTION: Recent studies have highlighted the prognostic value of easily accessible inflammatory markers, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) for predicting severe outcomes in patients affected by Coronavirus disease 2019 (COVID-19). Our study validates NLR and PLR cut-off values from a prior cohort at IRCCS Policlinico San Matteo (OSM) of Pavia, Italy, across two new cohorts from different hospitals. This aims to enhance the generalizability of these prognostic indicators. METHODS: In this retrospective cohort study, conducted at Milan's Ospedale Luigi Sacco (OLS) and IRCCS Ospedale Maggiore Policlinico (OMP) hospitals, we assess the predictive capacity of NLR and PLR for three main outcomes-non-invasive ventilation (NIV) or continuous positive airway pressure (CPAP) usage, invasive ventilation (IV), and death-in patients with COVID-19 at admission. For each outcome, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were computed separately for male and female cohorts. Distinct NLR and PLR cut-off values were used for men (7.00, 7.29, 7.00 for NLR; 239.22, 248.00, 250.39 for PLR) and women (6.36, 7.00, 6.28 for NLR; 233.00, 246.45, 241.54 for PLR), retrieved from the first cohort at OSM. RESULTS: A total of 3599 patients were included in our study, 1842 from OLS and 1757 from OMP. OLS and OMP sensitivity values for both NLR and PLR (NLR: 24-67%, PLR: 40-64%) were inferior to specificity values (NLR: 64-76%, PLR: 55-72%). Additionally, PPVs generally remained lower (< 63%), while NPVs consistently surpassed 68% for PLR and 72% for NLR. Finally, both PLR and NLR exhibited consistently higher NPVs for more severe outcomes (> 82%) compared to NPVs for CPAP/NIV. CONCLUSIONS: Consistent findings across diverse patient populations validate the reliability and applicability of NLR and PLR cut-off values. High NPVs emphasize their role in identifying individuals less likely to experience severe outcomes. These markers not only aid in risk stratification but also guide resource allocation in emergencies or limited-resource situations.

Preventing HIV mother-to-child transmission in a vertically infected pregnant woman with multiclass drug resistance, role of bis-in-die dolutegravir and neonatal AZT prophylaxis: A case report.

A suppressive antiretroviral therapy (ART) is necessary to prevent mother-to-child transmission (MTCT) of HIV during pregnancy. During this period, it is recommended to continue an ongoing safe and suppressive regimen, but history of multiclass drug-resistance (MDR) might need tailored, uncommon approaches posing tolerability and toxicity issues. This is the case of a 33 years of age, vertically infected woman with MDR HIV infection suppressed on a darunavir/cobicistat + atazanavir regimen switched during pregnancy to lamivudine + darunavir/ritonavir + dolutegravir 50 mg bis-in-die, maintaining complete viral suppression and delivering via caesarian section and without zidovudine (AZT) intrapartum prophylaxis a healthy HIV-negative newborn who received AZT post-exposure prophylaxis and showed regular growth patterns up to 2 years. Our case shows how archived MDR might complicate the preservation of HIV RNA suppression and highlights the importance of a tailored, multidisciplinary approach for pregnant women with MDR HIV and their newborns.

Clinical characteristics and outcomes of vaccinated patients hospitalised with SARS-CoV-2 breakthrough infection: Multi-IPV, a multicentre study in Northern Italy.

BACKGROUND: Despite the well-known efficacy of anti-COVID-19 vaccines in preventing morbidity and mortality, several vaccinated individuals are diagnosed with SARS-CoV-2 breakthrough infection, which might require hospitalisation. This multicentre, observational, and retrospective study aimed to investigate the clinical characteristics and outcomes of vaccinated vs. non-vaccinated patients, both hospitalised with SARS-CoV-2 infection in 3 major hospitals in Northern Italy. METHODS: Data collection was retrospective, and paper and electronic medical records of adult patients with a diagnosed SARS-CoV-2 infection were pseudo-anonymised and analysed. Vaccinated and non-vaccinated individuals were manually paired, using a predetermined matching criterion (similar age, gender, and date of hospitalisation). Demographic, clinical, treatment, and outcome data were compared between groups differing by vaccination status using Pearson's Chi-square and Mann-Whitney tests. Moreover, multiple logistic regression analyses were performed to assess the impact of vaccination status on ICU admission or intra-hospital mortality. RESULTS: Data from 360 patients were collected. Vaccinated patients presented with a higher prevalence of relevant comorbidities, like kidney replacement therapy or haematological malignancy, despite a milder clinical presentation at the first evaluation. Non-vaccinated patients required intensive care more often than their vaccinated counterparts (8.8% vs. 1.7%, p = 0.002). Contrariwise, no difference in intra-hospital mortality was observed between the two groups (19% vs. 20%, p = 0.853). These results were confirmed by multivariable logistic regressions, which showed that vaccination was significantly associated with decreased risk of ICU admission (aOR=0.172, 95%CI: 0.039-0.542, p = 0.007), but not of intra-hospital mortality (aOR=0.996, 95%CI: 0.582-1.703, p = 0.987). CONCLUSIONS: This study provides real-world data on vaccinated patients hospitalised with COVID-19 in Northern Italy. Our results suggest that COVID-19 vaccination has a protective role in individuals with higher risk profiles, especially regarding the need for ICU admission. These findings contribute to our understanding of SARS-CoV-2 infection outcomes among vaccinated individuals and emphasise the importance of vaccination in preventing severe disease, particularly in those countries with lower first-booster uptake rates.

Primary HIV infection features colonic damage and neutrophil inflammation yet containment of microbial translocation.

INTRODUCTION: Impairment of the gastrointestinal (GI) barrier leads to microbial translocation and peripheral immune activation which are linked to disease progression. Data in the setting of primary HIV/SIV infection suggest that gut barrier damage is one of the first events of the pathogenic cascade, preceding mucosal immune dysfunction and microbial translocation. We assessed gut structure and immunity as well as microbial translocation in acutely- and chronically-infected, combination cART-naïve individuals. METHODS: Fifteen people with Primary HIV infection (P-HIV) and 13 with Chronic HIV infection (C-HIV) c-ART naïve participants were cross-sectionally studied. Gut biopsies were analyzed in terms of gut reservoirs (total, integrated and unintegrated HIV DNA); tight junction proteins (E-cadherin, Zonula Occludens-1), CD4 expression, neutrophil myeloperoxidase (histochemical staining); collagen deposition (Masson staining). Flow cytometry was used to assess γδ T-cell frequency (CD3+panγδ+Vδ1+/Vδ2+). In plasma we measured microbial translocation (LPS, sCD14, EndoCAb) and gut barrier function (I-FABP) markers (ELISA). RESULTS: P-HIV displayed significantly higher tissue HIV DNA, yet neutrophil infiltration and collagen deposition in the gut were similar in the two groups. In contrast, microbial translocation markers were significantly lower in P-HIV compared to C-HIV. A trend to higher mucosal E-cadherin, and gut γδ T-cells was also observed in P-HIV. CONCLUSIONS: Early HIV infection features higher HIV DNA in the gut, yet comparable mucosal alterations to those observed in chronic infection. In contrast, microbial translocation is contained in primary HIV infection, likely due to a partial preservation of E-cadherin and mucosal immune subsets, namely γδ T-cells.

Incidence, microbiological and immunological characteristics of ventilator-associated pneumonia assessed by bronchoalveolar lavage and endotracheal aspirate in a prospective cohort of COVID-19 patients: CoV-AP study.

BACKGROUND: No univocal recommendation exists for microbiological diagnosis of ventilator-associated pneumonia (VAP). Sampling of either proximal or distal respiratory tract likely impacts on the broad range of VAP incidence between cohorts. Immune biomarkers to rule-in/rule-out VAP diagnosis, although promising, have not yet been validated. COVID-19-induced ARDS made VAP recognition even more challenging, often leading to overdiagnosis and overtreatment. We evaluated the impact of different respiratory samples and laboratory techniques on VAP incidence and microbiological findings in COVID-19 patients. METHODS: Prospective single-centre cohort study conducted among COVID-19 mechanically ventilated patients in Policlinico Hospital (Milan, Italy) from January 2021 to May 2022. Microbiological confirmation of suspected VAP (sVAP) was based on concomitant endotracheal aspirates (ETA) and bronchoalveolar lavage (BAL). Conventional and fast microbiology (FILMARRAY® Pneumonia Panel plus, BALFAPPP) as well as immunological markers (immune cells and inflammatory cytokines) was analysed. RESULTS: Seventy-nine patients were included. Exposure to antibiotics and steroid therapy before ICU admission occurred in 51/79 (64.6%) and 60/79 (65.9%) patients, respectively. Median duration of MV at VAP suspicion was 6 (5-9) days. Incidence rate of microbiologically confirmed VAP was 33.1 (95% CI 22.1-44.0) and 20.1 (95% CI 12.5-27.7) according to ETA and BAL, respectively. Concordance between ETA and BAL was observed in 35/49 (71.4%) cases, concordance between BALFAPPP and BAL in 39/49 (79.6%) cases. With BAL as reference standard, ETA showed 88.9% (95% CI 70.8-97.7) sensitivity and 50.0% (95% CI 28.2-71.8) specificity (Cohen's Kappa 0.40, 95% CI 0.16-0.65). BALFAPPP showed 95.0% (95% CI 75.1-99.9) sensitivity and 69% (95% CI 49.2-84.7) specificity (Cohen's Kappa 0.60, 95% CI 0.39-0.81). BAL IL-1ß differed significantly between VAP (135 (IQR 11-450) pg/ml) and no-VAP (10 (IQR 2.9-105) pg/ml) patients (P = 0.03). CONCLUSIONS: In COVID-19 ICU patients, differences in microbial sampling at VAP suspicion could lead to high variability in VAP incidence and microbiological findings. Concordance between ETA and BAL was mainly limited by over 20% of ETA positive and BAL negative samples, while BALFAPPP showed high sensitivity but limited specificity when evaluating in-panel targets only. These factors should be considered when comparing results of cohorts with different sampling. BAL IL-1ß showed potential in discriminating microbiologically confirmed VAP. CLINICAL TRIAL REGISTRATION: NCT04766983, registered on February 23, 2021.

Characterization of Immunogenicity and Safety of COVID-19 mRNA-1273 in HIV-Positive Italian Patients with Hemophilia: A Prospective Single-Center Cohort Study.

To characterize the immunogenicity of mRNA-1273 (Moderna, Cambridge, MA, USA) vaccine in HIV-positive hemophilic patients during the third COVID-19 wave in Italy and to investigate biomarkers of coagulation and endothelial perturbation before and after complete vaccination schedule, twenty-three consecutive adult HIV-positive patients with hemophilia were included. Blood was collected before and two weeks after vaccination. We measured anti-SARS-CoV-2 spike protein antibodies to assess immunogenicity; circulating biomarkers of coagulation (protein C and D-dimer), endothelial perturbation (von Willebrand factor (VWF)) and anti-Platelet Factor 4 (PF4) antibodies were analyzed. Flow-based analysis of thrombus formation was performed in nine patients using a flow-chamber device. Two weeks after completing the vaccination schedule, all patients had anti-spike antibodies values consistent with an effective immunization. Mean (±standard deviation) basal values of protein C and VWF (106 ± 21% and 171 ± 45%, respectively) were not significantly different from data obtained two weeks after the second dose (103 ± 20%, 162 ± 43%, respectively). D-dimer median values (interquartile range) were not significantly different at baseline (442 (603-142) ng/mL) and after the second dose (477 (654-262) ng/mL). Anti-PF4 antibodies were detected in three patients with no associated clinical manifestations. No significant differences were found in flow-based analysis of thrombus formation. Our data demonstrate that in HIV-positive patients with hemophilia, SARS-CoV-2 vaccination is effective and safe, with no effects on coagulation and endothelial perturbation.

The role of immune suppression in COVID-19 hospitalization: clinical and epidemiological trends over three years of SARS-CoV-2 epidemic.

Specific immune suppression types have been associated with a greater risk of severe COVID-19 disease and death. We analyzed data from patients >17 years that were hospitalized for COVID-19 at the "Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico" in Milan (Lombardy, Northern Italy). The study included 1727 SARS-CoV-2-positive patients (1,131 males, median age of 65 years) hospitalized between February 2020 and November 2022. Of these, 321 (18.6%, CI: 16.8-20.4%) had at least one condition defining immune suppression. Immune suppressed subjects were more likely to have other co-morbidities (80.4% vs. 69.8%, p < 0.001) and be vaccinated (37% vs. 12.7%, p < 0.001). We evaluated the contribution of immune suppression to hospitalization during the various stages of the epidemic and investigated whether immune suppression contributed to severe outcomes and death, also considering the vaccination status of the patients. The proportion of immune suppressed patients among all hospitalizations (initially stable at <20%) started to increase around December 2021, and remained high (30-50%). This change coincided with an increase in the proportions of older patients and patients with co-morbidities and with a decrease in the proportion of patients with severe outcomes. Vaccinated patients showed a lower proportion of severe outcomes; among non-vaccinated patients, severe outcomes were more common in immune suppressed individuals. Immune suppression was a significant predictor of severe outcomes, after adjusting for age, sex, co-morbidities, period of hospitalization, and vaccination status (OR: 1.64; 95% CI: 1.23-2.19), while vaccination was a protective factor (OR: 0.31; 95% IC: 0.20-0.47). However, after November 2021, differences in disease outcomes between vaccinated and non-vaccinated groups (for both immune suppressed and immune competent subjects) disappeared. Since December 2021, the spread of the less virulent Omicron variant and an overall higher level of induced and/or natural immunity likely contributed to the observed shift in hospitalized patient characteristics. Nonetheless, vaccination against SARS-CoV-2, likely in combination with naturally acquired immunity, effectively reduced severe outcomes in both immune competent (73.9% vs. 48.2%, p < 0.001) and immune suppressed (66.4% vs. 35.2%, p < 0.001) patients, confirming previous observations about the value of the vaccine in preventing serious disease.

HIV-DNA decrease during treatment in primary HIV-1 infection with three different drug regimens: Italian Network of Acute HIV Infection (INACTION) clinical trial.

As the introduction of antiretroviral therapy (ART) during primary HIV-1 infection (PHI) could restrict the establishment of HIV reservoirs, we aimed to assess the effect of three different ART regimens on HIV-DNA load in people living with HIV (PLWH), who started ART in PHI. Randomized, open-label, multicentric study, including subjects in PHI (defined as an incomplete HIV-1 Western blot and detectable plasma HIV-RNA) in the Italian Network of Acute HIV Infection cohort. Participants were randomly assigned (10:10:8) to a fixed-dose combination of tenofovir alafenamide fumarate (TAF) 10 mg plus emtricitabine (FTC) 200 mg, darunavir 800 mg, and cobicistat 150 mg once daily (group A), or TAF 25 mg plus FTC 200 mg, dolutegravir 50 mg once daily (group B), or an intensified four-drug regimen (TAF 10 mg plus FTC 200 mg, dolutegravir 50 mg, darunavir 800 mg, and cobicistat 150 mg once daily) (group C). The primary endpoint was the decrease of HIV-DNA copies/106 peripheral blood mononuclear cells (PBMCs) at weeks (W) 12 and 48. Secondary endpoints were increased in CD4+ cells and in CD4+/CD8+ ratio and percentage of PLWH reaching undetectable HIV-RNA. HIV-DNA was quantified by Droplet Digital PCR (Biorad QX100) and normalized to RPP30 reference gene. This study was registered in ClinicalTrials.gov (number NCT04225325). Among 78 participants enrolled, 30 were randomized to group 1, 28 to group 2, and 20 to group 3. At baseline, median CD4+ count was 658/µL (476-790), HIV-RNA 5.37 (4.38, 6.12) log10 copies/mL, without statistical difference in their change among groups at weeks 12 and 48 (p = 0.432 and 0.234, respectively). The trial was prematurely discontinued for slow accrual and for COVID-19 pandemic-associated restrictions. In the per-protocol analysis, PLWH (n = 72) with undetectable viral load was 54.3% at W12 and 86.4% at W48. Interestingly, the CD4/CD8 ratio progressively increased over time, up to normalization in almost half of the cohort by week 48, despite a deflection in group 3; no difference was observed by the Fiebig stage (I-III vs. IV-VI). HIV-DNA decreased from 4.46 (4.08, 4.81) log10 copies/106 PBMCs to 4.22 (3.79, 4.49) at week 12, and 3.87 (3.46, 4.34) at week 48, without difference among groups. At multivariable analysis, HIV-DNA delta at W48 was associated only with the increase of CD4+ count by 100 cells/mm3 but not with the Fiebig stage, the CD4+/CD8+ ratio, and treatment arm, despite a higher decrease in group 3. Six adverse events were recorded during our study, which did not cause any withdrawal from the study. We observed a decrease in HIV-DNA from baseline to W48 in PLWH treated during PHI, associated with an increase in CD4+ count, unrelated to the treatment arm.

Perfusion fluid-related infections in liver transplant recipients: A 5-year, single-center, retrospective study.

BACKGROUND: Perfusion fluid (PRF) is employed in liver transplantation (LTx) to maintain graft viability. Still, it represents a new potential way of infection transmission in LTx recipients (LTRs). Currently, no systematic research has investigated this topic. METHODS: Five-year single-center retrospective study conducted on LTRs from January 2017 to December 2021. We analyzed the incidence of positive PRF culture (PRF+) and perfusion fluid-related infections (PRF-RI) and their associated factors. We also assessed 1-year mortality, both overall and infection-related. RESULTS: Overall, 234 LTx were included. PRF+ were found in 31/234 (13.2%) LTx for a total of 37 isolates, with >1 isolate identified in 5 (2.1%) cases. High-risk microorganisms (Enterobacterales 13/37, Enterococcus spp. 4/37, S. aureus 3/37, P. aeruginosa 2/37) were isolated in 25/37 (67.6%) LTRs, the remaining being coagulase-negative staphylococci (12/37, 32.4%). Antimicrobial prophylaxis was administered to all LTRs, always active against the isolate even if suboptimal in 19 cases (61.3%). PRF-RI developed in 4/234 LTx (1.7%), and prophylaxis was considered suboptimal in 2/4 of them. The isolation of >1 microorganism in PRF culture was associated with an increased risk of developing PRF-RI (OR 37.5 [95%CI 2.6-548.4], p = .01). PRF-RI were associated with longer ICU stays (p = .005) and higher 1-year mortality, both overall and related to infections (p = .001). CONCLUSION: Despite PRF+ being infrequent, only a minority of patients develops PRF-RI. Nonetheless, once occurred, PRF-RI seems to increase morbidity and mortality rates.

Multidrug-Resistant Bacterial Colonization and Infections in Large Retrospective Cohort of Mechanically Ventilated COVID-19 Patients1.

Few data are available on incidence of multidrug-resistant organism (MDRO) colonization and infections in mechanically ventilated patients, particularly during the COVID-19 pandemic. We retrospectively evaluated all patients admitted to the COVID-19 intensive care unit (ICU) of Hub Hospital in Milan, Italy, during October 2020‒May 2021. Microbiologic surveillance was standardized with active screening at admission and weekly during ICU stay. Of 435 patients, 88 (20.2%) had MDROs isolated ≤48 h after admission. Of the remaining patients, MDRO colonization was diagnosed in 173 (51.2%), MDRO infections in 95 (28.1%), and non-MDRO infections in 212 (62.7%). Non-MDRO infections occurred earlier than MDRO infections (6 days vs. 10 days; p<0.001). Previous exposure to antimicrobial drugs within the ICU was higher in MDRO patients than in non-MDRO patients (116/197 [58.9%] vs. 18/140 [12.9%]; p<0.001). Our findings might serve as warnings for future respiratory viral pandemics and call for increased measures of antimicrobial stewardship and infection control.

Preliminary Evidence of Good Safety Profile and Outcomes of Early Treatment with Tixagevimab/Cilgavimab Compared to Previously Employed Monoclonal Antibodies for COVID-19 in Immunocompromised Patients.

OBJECTIVES: Monoclonal antibodies (mAbs) have proven to be a valuable tool against COVID-19, mostly among subjects with risk factors for progression to severe illness. Tixagevimab/cilgavimab (TIX/CIL), a combination of two Fc-modified human monoclonal antibodies, has been recently approved to be employed as early treatment. METHODS: Two groups of immunocompromised patients exposed to different early treatments (i.e., TIX/CIL vs. other mAbs [casirivimab/imdevimab, bamlanivimab/etesevimab, sotrovimab]) were compared in terms of clinical outcomes (hospitalisation and mortality within 14 days from administration) and time to the negativity of nasal swabs. We used either Pearson's chi-square or Fisher's exact test for categorical variables, whereas the Wilcoxon rank-sum test was employed for continuous ones. Kaplan-Meier curves were produced to compare the time to nasopharyngeal swab negativity. RESULTS: Early treatment with TIX/CIL was administered to 19 immunocompromised patients, while 89 patients received other mAbs. Most of them were solid organ transplant recipients or suffering from hematologic or solid malignancies. Overall, no significant difference was observed between the two groups regarding clinical outcomes. In the TIX/CIL group, one patient (1/19, 5.3%), who was admitted to the emergency room within the first 14 days from treatment and was hospitalised due to COVID-19 progression, died. Regarding the time to nasal swab negativity, no significant difference (p = 0.088) emerged. CONCLUSIONS: Early treatment of SARS-CoV-2 infection with TIX/CIL showed favourable outcomes in a small group of immunocompromised patients, reporting no significant difference compared to similar patients treated with other mAbs.

Genomic Characterization of Carbapenem-Resistant Acinetobacter baumannii (CRAB) in Mechanically Ventilated COVID-19 Patients and Impact of Infection Control Measures on Reducing CRAB Circulation during the Second Wave of the SARS-CoV-2 Pandemic in Milan, Italy.

COVID-19 has significantly affected hospital infection prevention and control (IPC) practices, especially in intensive care units (ICUs). This frequently caused dissemination of multidrug-resistant organisms (MDROs), including carbapenem-resistant Acinetobacter baumannii (CRAB). Here, we report the management of a CRAB outbreak in a large ICU COVID-19 hub Hospital in Italy, together with retrospective genotypic analysis by whole-genome sequencing (WGS). Bacterial strains obtained from severe COVID-19 mechanically ventilated patients diagnosed with CRAB infection or colonization between October 2020 and May 2021 were analyzed by WGS to assess antimicrobial resistance and virulence genes, along with mobile genetic elements. Phylogenetic analysis in combination with epidemiological data was used to identify putative transmission chains. CRAB infections and colonization were diagnosed in 14/40 (35%) and 26/40 (65%) cases, respectively, with isolation within 48 h from admission in 7 cases (17.5%). All CRAB strains belonged to Pasteur sequence type 2 (ST2) and 5 different Oxford STs and presented blaOXA-23 gene-carrying Tn2006 transposons. Phylogenetic analysis revealed the existence of four transmission chains inside and among ICUs, circulating mainly between November and January 2021. A tailored IPC strategy was composed of a 5-point bundle, including ICU modules' temporary conversion to CRAB-ICUs and dynamic reopening, with limited impact on ICU admission rate. After its implementation, no CRAB transmission chains were detected. Our study underlies the potentiality of integrating classical epidemiological studies with genomic investigation to identify transmission routes during outbreaks, which could represent a valuable tool to ensure IPC strategies and prevent the spread of MDROs. IMPORTANCE Infection prevention and control (IPC) practices are of paramount importance for preventing the spread of multidrug-resistant organisms (MDROs) in hospitals, especially in the intensive care unit (ICU). Whole-genome sequencing (WGS) is seen as a promising tool for IPC, but its employment is currently still limited. COVID-19 pandemics have posed dramatic challenges in IPC practices, causing worldwide several outbreaks of MDROs, including carbapenem-resistant Acinetobacter baumannii (CRAB). We present the management of a CRAB outbreak in a large ICU COVID-19 hub hospital in Italy using a tailored IPC strategy that allowed us to contain CRAB transmission while preventing ICU closure during a critical pandemic period. The analysis of clinical and epidemiological data coupled with retrospective genotypic analysis by WGS identified different putative transmission chains and confirmed the effectiveness of the IPC strategy implemented. This could be a promising approach for future IPC strategies.

Gut and airway microbiota dysbiosis and their role in COVID-19 and long-COVID.

The gut microbiota plays a crucial role in human health and disease. Gut dysbiosis is known to be associated with increased susceptibility to respiratory diseases and modifications in the immune response and homeostasis of the lungs (the so-called gut-lung axis). Furthermore, recent studies have highlighted the possible role of dysbiosis in neurological disturbances, introducing the notion of the "gut-brain axis." During the last 2 years, several studies have described the presence of gut dysbiosis during coronavirus disease 2019 (COVID-19) and its relationship with disease severity, SARS-CoV-2 gastrointestinal replication, and immune inflammation. Moreover, the possible persistence of gut dysbiosis after disease resolution may be linked to long-COVID syndrome and particularly to its neurological manifestations. We reviewed recent evidence on the association between dysbiosis and COVID-19, investigating the possible epidemiologic confounding factors like age, location, sex, sample size, the severity of disease, comorbidities, therapy, and vaccination status on gut and airway microbial dysbiosis in selected studies on both COVID-19 and long-COVID. Moreover, we analyzed the confounding factors strictly related to microbiota, specifically diet investigation and previous use of antibiotics/probiotics, and the methodology used to study the microbiota (α- and ß-diversity parameters and relative abundance tools). Of note, only a few studies focused on longitudinal analyses, especially for long-term observation in long-COVID. Lastly, there is a lack of knowledge regarding the role of microbiota transplantation and other therapeutic approaches and their possible impact on disease progression and severity. Preliminary data seem to suggest that gut and airway dysbiosis might play a role in COVID-19 and in long-COVID neurological symptoms. Indeed, the development and interpretation of these data could have important implications for future preventive and therapeutic strategies.

Changes in upper airways microbiota in ventilator-associated pneumonia.

BACKGROUND: The role of upper airways microbiota and its association with ventilator-associated pneumonia (VAP) development in mechanically ventilated (MV) patients is unclear. Taking advantage of data collected in a prospective study aimed to assess the composition and over-time variation of upper airway microbiota in patients MV for non-pulmonary reasons, we describe upper airway microbiota characteristics among VAP and NO-VAP patients. METHODS: Exploratory analysis of data collected in a prospective observational study on patients intubated for non-pulmonary conditions. Microbiota analysis (trough 16S-rRNA gene profiling) was performed on endotracheal aspirates (at intubation, T0, and after 72 h, T3) of patients with VAP (cases cohort) and a subgroup of NO-VAP patients (control cohort, matched according to total intubation time). RESULTS: Samples from 13 VAP patients and 22 NO-VAP matched controls were analyzed. At intubation (T0), patients with VAP revealed a significantly lower microbial complexity of the microbiota of the upper airways compared to NO-VAP controls (alpha diversity index of 84 ± 37 and 160 ± 102, in VAP and NO_VAP group, respectively, p-value < 0.012). Furthermore, an overall decrease in microbial diversity was observed in both groups at T3 as compared to T0. At T3, a loss of some genera (Prevotella 7, Fusobacterium, Neisseria, Escherichia-Shigella and Haemophilus) was found in VAP patients. In contrast, eight genera belonging to the Bacteroidetes, Firmicutes and Fusobacteria phyla was predominant in this group. However, it is unclear whether VAP caused dysbiosis or dysbiosis caused VAP. CONCLUSIONS: In a small sample size of intubated patients, microbial diversity at intubation was less in patients with VAP compared to patients without VAP.

Plasma Proteomic Variables Related to COVID-19 Severity: An Untargeted nLC-MS/MS Investigation.

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection leads to a wide range of clinical manifestations and determines the need for personalized and precision medicine. To better understand the biological determinants of this heterogeneity, we explored the plasma proteome of 43 COVID-19 patients with different outcomes by an untargeted liquid chromatography-mass spectrometry approach. The comparison between asymptomatic or pauci-symptomatic subjects (MILDs), and hospitalised patients in need of oxygen support therapy (SEVEREs) highlighted 29 proteins emerged as differentially expressed: 12 overexpressed in MILDs and 17 in SEVEREs. Moreover, a supervised analysis based on a decision-tree recognised three proteins (Fetuin-A, Ig lambda-2chain-C-region, Vitronectin) that are able to robustly discriminate between the two classes independently from the infection stage. In silico functional annotation of the 29 deregulated proteins pinpointed several functions possibly related to the severity; no pathway was associated exclusively to MILDs, while several only to SEVEREs, and some associated to both MILDs and SEVEREs; SARS-CoV-2 signalling pathway was significantly enriched by proteins up-expressed in SEVEREs (SAA1/2, CRP, HP, LRG1) and in MILDs (GSN, HRG). In conclusion, our analysis could provide key information for 'proteomically' defining possible upstream mechanisms and mediators triggering or limiting the domino effect of the immune-related response and characterizing severe exacerbations.

Non-B subtypes account for a large proportion of clustered primary HIV-1 infections in Italy.

OBJECTIVES AND DESIGN: Using pol sequences obtained for routine resistance testing, we characterised the molecular patterns of HIV-1 transmission and factors associated with being part of a transmission cluster among individuals who in 2008-2014 presented with primary HIV-1 infection (PHI) at 11 urban centres across Italy. METHODS: Pol sequences were obtained by Sanger sequencing. Transmission clusters were identified by phylogenetic analysis (maximum likelihood method, confirmed by Bayesian analysis). Multivariable logistic regression explored factors associated with a participant being part of a transmission cluster. RESULTS: The PHI cohort comprised 186 participants (159/186, 85.5% males) with median age 44 years, median CD4 count 464 cells/mm3 and median plasma HIV-1 RNA 5.6 log10 copies/mL. Drug resistance associated mutations were found in 16/186 (8.6%). A diversity of non-B subtypes accounted for 60/186 (32.3%) of all infections. A total of 17 transmission clusters were identified, including 44/186 (23.7%) participants. Each cluster comprised 2-6 sequences. Non-B subtypes accounted for seven clusters and 22/44 (50%) of clustered sequences. In multivariable logistic regression analysis, factors associated with being part of a transmission cluster comprised harbouring a non-B subtype (adjusted OR (adjOR) 2.28; 95% CI 1.03 to 5.05; p=0.04) and showing a lower plasma HIV-1 RNA (adjOR 0.80, 95% CI 0.64 to 0.99; p=0.04). CONCLUSIONS: There was a large contribution of diverse non-B subtypes to transmission clusters among people presenting with acute or recent HIV-1 infection in this cohort, illustrating the evolving dynamics of the HIV-1 epidemic in Italy, where subtype B previously dominated.

Reply to "successful early use of anti-SARS-CoV-2 monoclonal neutralizing antibodies in SARS-CoV-2 infected hematological patients-A Czech multicenter experience": A case series of SARS-CoV-2 Omicron infection and aggressive lymphoma in the Sotrovimab era.

A prospective multicentre experience of early administration of anti-SARS-CoV-2 spike protein neutralizing monoclonal antibodies (MA) with efficacy among patients with hematological malignancies and early-stage COVID- 19 was reported by Weinbergerová et al. The study validated the safety and efficacy of MA early use among hematological patients with newly diagnosed early-stage COVID-19 in terms of alleviating infection course and decreasing mortality. However no reference to new variant (Delta and Omicron) or other MA (e.g., Sotrovimab) has been reported. We reported our monocentric experience of 8 aggressive lymphoma patients with Omicron infection, 7 of whom treated with this MA in our Institution between December 2021 and February 2022. Among the patients treated with Sotrovimab nobody experienced neither SARS-CoV2 reactivation, nor other infectious events. One patients on active lymphoma treatment was hospitalized for pneumonia and treated with remdesivir. In 4/8 patients negativization of molecular swab occurred concomitantly to symptoms resolution with a median of 5.25 days, while the other 4 patients remained persistently positive with a median of 26.3 days. In this group, in order to maintain the chemo/chemoimmunotherapy (CT/CIT) dose-density, lymphoma treatment was reassumed independently on molecular swab analysis. SARS-CoV-2 negativization occurred with a median of 7.7 days after the resumption of CT/CIT. The one patient treated with remdesivir, although still positive to molecular swab, restarted R-COMP regimen at symptoms resolution too, but experienced an Omicron pneumonia exacerbation. This is the first case series reported in literature of patients affected by Omicron variant in which Sotrovimab seems to provide a resolution of COVID-19 disease, even in patient with molecular swab positive persistence too. Patients with aggressive lymphoma histologies should not be deprived of the best available treatment of their disease after sotrovimab administration, even in the presence of a still positive Omicron swab.

Increase in invasive group A streptococcal infections in Milan, Italy: a genomic and clinical characterization.

Background: Group A Streptococcus (GAS) causes multiple clinical manifestations, including invasive (iGAS) or even life-threatening (severe-iGAS) infections. After the drop in cases during COVID-19 pandemic, in 2022 a sharp increase of GAS was reported globally. Methods: GAS strains collected in 09/2022-03/2023 in two university hospitals in Milan, Italy were retrospectively analyzed. Clinical/epidemiological data were combined with whole-genome sequencing to: (i) define resistome/virulome, (ii) identify putative transmission chains, (iii) explore associations between emm-types and clinical severity. Results: Twenty-eight isolates were available, 19/28 (67.9%) from adults and 9/28 (32.1%) from pediatric population. The criteria for iGAS were met by 19/28 cases (67.9%), of which 11/19 (39.3%) met the further criteria for severe-iGAS. Pediatric cases were mainly non-invasive infections (8/9, 88.9%), adult cases were iGAS and severe-iGAS in 18/19 (94.7%) and 10/19 (52.6%), respectively. Thirteen emm-types were detected, the most prevalent being emm1 and emm12 (6/28 strains each, 21.4%). Single nucleotide polymorphism (SNP) analysis of emm1.0 and emm12.0 strains revealed pairwise SNP distance always >10, inconsistent with unique transmission chains. Emm12.0-type, found to almost exclusively carry virulence factors speH and speI, was mainly detected in children and in no-iGAS infections (55.6 vs. 5.3%, p = 0.007 and 66.7 vs. 0.0%, p < 0.001, respectively), while emm1.0-type was mainly detected in severe-iGAS (0.0 vs. 45.5%, p = 0.045). Conclusions: This study showed that multiple emm-types contributed to a 2022/2023 GAS infection increase in two hospitals in Milan, with no evidence of direct transmission chains. Specific emm-types could be associated with disease severity or invasiveness. Overall, these results support the integration of classical epidemiological studies with genomic investigation to appropriately manage severe infections and improve surveillance.

Effectiveness of a Multifaced Antibiotic Stewardship Program: A Pre-Post Study in Seven Italian ICUs.

Multidrug resistance has become a serious threat for health, particularly in hospital-acquired infections. To improve patients' safety and outcomes while maintaining the efficacy of antimicrobials, complex interventions are needed involving infection control and appropriate pharmacological treatments in antibiotic stewardship programs. We conducted a multicenter pre-post study to assess the impact of a stewardship program in seven Italian intensive care units (ICUs). Each ICU was visited by a multidisciplinary team involving clinicians, microbiologists, pharmacologists, infectious disease specialists, and data scientists. Interventions were targeted according to the characteristics of each unit. The effect of the program was measured with a panel of indicators computed with data from the MargheritaTre electronic health record. The median duration of empirical therapy decreased from 5.6 to 4.6 days and the use of quinolones dropped from 15.3% to 6%, both p < 0.001. The proportion of multi-drug-resistant bacteria (MDR) in ICU-acquired infections fell from 57.7% to 48.8%. ICU mortality and length of stay remained unchanged, indicating that reducing antibiotic administration did not harm patients' safety. This study shows that our stewardship program successfully improved the management of infections. This suggests that policy makers should tackle multidrug resistance with a multidisciplinary approach based on continuous monitoring and personalised interventions.

Prognostic Value of Mid-Region Proadrenomedullin and In Vitro Interferon Gamma Production for In-Hospital Mortality in Patients with COVID-19 Pneumonia and Respiratory Failure: An Observational Prospective Study.

Coagulopathy and immune dysregulation have been identified as important causes of adverse outcomes in coronavirus disease (COVID-19). Mid-region proadrenomedullin (MR-proADM) is associated with endothelial damage and has recently been proposed as a prognostic factor in COVID-19. In non-COVID-19 immunocompromised patients, low in vitro interferon gamma (IFNγ) production correlates with infection risk and mortality. This prospective, monocentric, observational study included adult patients consecutively admitted with radiologic evidence of COVID-19 pneumonia and respiratory failure. MR-proADM and in vitro IFNγ production were measured at T0 (day 1 from admission) and T1 (day 7 from enrollment). One hundred patients were enrolled. Thirty-six percent were females, median age 65 (Q1−Q3 54.5−75) years, and 58% had ≥1 comorbidity. Only 16 patients had received COVID-19 vaccination before hospitalization. At admission, the median PaO2:FiO2 ratio was 241 (157−309) mmHg. In-hospital mortality was 13%. MR-proADM levels differed significantly between deceased and survivors both at T0 (1.41 (1.12−1.77) nmol/L vs. 0.79 (0.63−1.03) nmol/L, p < 0.001) and T1 (1.67 (1.08−1.96) nmol/L vs. 0.66 (0.53−0.95) nmol/L, p < 0.001). In vitro IFNγ production at T0 and T1 did not vary between groups. When only the subset of non-vaccinated patients was considered, both biomarkers at T1 resulted significantly associated with in-hospital mortality. AUROC for MR-proADM at T0 to predict in-hospital mortality was 0.87 (95%CI 0.79−0.94), with the best cut-off point at 1.04 nmol/L (92% sensitivity, 75% specificity and 98% negative predictive value). In patients with COVID-19 pneumonia and different degrees of respiratory failure, MR-proADM at admission and during hospitalization resulted strongly associated with in-hospital mortality. Low in vitro IFNγ production after the first week of hospitalization was associated with mortality in non-vaccinated patients possibly identifying the subgroup characterized by a higher degree of immune suppression.