Background In vitro data support the use of combination of aztreonam (ATM) with ceftazidime-avibactam (CAZ-AVI), but clinical studies are lacking. The aim of our study was to compare the outcome of patients with bloodstream infections (BSIs) due to MBLs-producing Enterobacterales treated either with CAZ-AVI plus ATM or other active antibiotics (OAAs). Methods Prospective observational study including patients admitted to three hospitals in Italy and Greece. The primary outcome measure was the 30-day all-cause mortality. Secondary outcomes were clinical failure at day 14 and length of stay (LOS) after BSI diagnosis. Cox regression analysis including a propensity score (PS) for receiving CAZ-AVI plus ATM was performed to evaluate primary and secondary outcomes. A PS-based matched analysis was also performed. Results We enrolled 102 pts with BSI, 82 had infections caused by NDM-producing (79 K.pneumoniae and 3 E.coli) and 20 by VIM-producing (14 K.pneumoniae, 5 Enterobacter spp, 1 M.morganii) strains. The 30-day mortality rate was 19.2% in CAZ-AVI/ATM group vs 44% in OAAs group (p=0.007). The PS-adjusted analysis showed that the use of CAZ-AVI/ATM was associated with lower 30-day mortality (HR 0.37, 95% CI 0.13-0.74, p=0.01), lower clinical failure at day 14 (HR 0.30, 95% CI 0.14-0.65, p=0.002) and shorter LOS (sHR 0.49, 95% CI 0.30-0.82, p=0.007). The PS-matched analysis confirmed these findings. Conclusions CAZ-AVI/ATM combination offers therapeutic advantage compared to OAAs for patients with BSI due to MBL-producing Enterobacterales. Further studies are warranted.

Background Bacterial and fungal superinfections may complicate the course of hospitalized patients with COVID-19. Objectives To identify predictors of superinfections in COVID-19. Methods Prospective, observational study including patients with COVID-19 consecutively admitted to the University Hospital of Pisa, Italy, between 4 March and 30 April 2020. Clinical data and outcomes were registered. Superinfection was defined as a bacterial or fungal infection that occurred ≥48 h after hospital admission. A multivariate analysis was performed to identify factors independently associated with superinfections. Results Overall, 315 patients with COVID-19 were hospitalized and 109 episodes of superinfections were documented in 69 (21.9%) patients. The median time from admission to superinfection was 19 days (range 11–29.75). Superinfections were caused by Enterobacterales (44.9%), non-fermenting Gram-negative bacilli (15.6%), Gram-positive bacteria (15.6%) and fungi (5.5%). Polymicrobial infections accounted for 18.3%. Predictors of superinfections were: intestinal colonization by carbapenem-resistant Enterobacterales (OR 16.03, 95% CI 6.5–39.5, P < 0.001); invasive mechanical ventilation (OR 5.6, 95% CI 2.4–13.1, P < 0.001); immunomodulatory agents (tocilizumab/baricitinib) (OR 5.09, 95% CI 2.2–11.8, P < 0.001); C-reactive protein on admission >7 mg/dl (OR 3.59, 95% CI 1.7–7.7, P = 0.001); and previous treatment with piperacillin/tazobactam (OR 2.85, 95% CI 1.1–7.2, P = 0.028). Length of hospital stay was longer in patients who developed superinfections ompared with those who did not (30 versus 11 days, P < 0.001), while mortality rates were similar (18.8% versus 23.2%, P = 0.445). Conclusions The risk of bacterial and fungal superinfections in COVID-19 is consistent. Patients who need empiric broad-spectrum antibiotics and immunomodulant drugs should be carefully selected. Infection control rules must be reinforced.

Objectives To evaluate the impact of low molecular weight heparin (LMWH) on the outcome of patients with SARS-CoV-2 pneumonia. Methods Prospective observational study including consecutive patients with laboratory confirmed SARS-CoV-2 pneumonia admitted to the University Hospital of Pisa (4th March-30th April 2020). Demographic, clinical, and outcome data were collected. The primary endpoint was 30-day mortality. The secondary endpoint was a composite of death or severe ARDS. LMWH, hydroxychloroquine, doxycycline, macrolides, antiretrovirals, remdesivir, baricitinib, tocilizumab, and steroids were evaluated as treatment exposures of interest. First, a Cox-regression analysis, in which treatments were introduced as time-dependent variables, was performed to evaluate the association of exposures and outcomes. Then, a time-dependent Propensity-score (PS) was calculated and a PS-matching performed for each treatment variable. Results Among 315 patients with SARS-CoV-2 pneumonia, 70 (22.2%) died during hospital stay. The composite endpoint was achieved by 114 (36.2%) patients. Overall, 244 (77.5%) patients received LMWH, 238 (75.5%) hydroxychloroquine, 201 (63.8%) proteases inhibitors, 150 (47.6%) doxycycline, 141 (44.8%) steroids, 42 (13.3%) macrolides, 40 (12.7%) baricitinib, 13 (4.1%) tocilizumab, and 13 (4.1%) remdesivir. At multivariate analysis, LMWH was associated with a reduced risk of 30-day mortality (HR 0.36 [95% CI 0.21-0.6], p<0.001) and composite endpoint (HR 0.61 [95% CI 0.39-0.95], p=0.029). The PS-matched cohort of 55 couples confirmed the same results for both primary and secondary endpoint. Conclusions This study suggests that LMWH might reduce the risk of in-hospital mortality and severe ARDS in Covid-19. Randomized controlled trials are warranted to confirm these preliminary findings.

IMPORTANCEConvalescent plasma (CP) has been generally unsuccessful in preventing worsening of respiratory failure or death in hospitalized patients with COVID-19 pneumonia. OBJECTIVE To evaluate the efficacy of CP plus standard therapy (ST) vs ST alone in preventing worsening respiratory failure or death in patients with COVID-19 pneumonia. DESIGN, SETTING, AND PARTICIPANTS This prospective, open-label, randomized clinical trial enrolled (1:1 ratio) hospitalized patients with COVID-19 pneumonia to receive CP plus ST or ST alone between July 15 and December 8, 2020, at 27 clinical sites in Italy. Hospitalized adults with COVID-19 pneumonia and a partial pressure of oxygen-to-fraction of inspired oxygen (PaO 2 /FiO 2 ) ratio between 350 and 200 mm Hg were eligible. INTERVENTIONS Patients in the experimental group received intravenous high-titer CP (Ն1:160, by microneutralization test) plus ST. The volume of infused CP was 200 mL given from 1 to a maximum of 3 infusions. Patients in the control group received ST, represented by remdesivir, glucocorticoids, and low-molecular weight heparin, according to the Agenzia Italiana del Farmaco recommendations. MAIN OUTCOMES AND MEASURESThe primary outcome was a composite of worsening respiratory failure (PaO 2 /FiO 2 ratio <150 mm Hg) or death within 30 days from randomization. RESULTSOf the 487 randomized patients (241 to CP plus ST; 246 to ST alone), 312 (64.1%) were men; the median (IQR) age was 64 (54.0-74.0) years. The modified intention-to-treat population included 473 patients. The primary end point occurred in 59 of 231 patients (25.5%) treated with CP and ST and in 67 of 239 patients (28.0%) who received ST (odds ratio, 0.88; 95% CI, 0.59-1.33; P = .54). Adverse events occurred more frequently in the CP group (12 of 241 [5.0%]) compared with the control group (4 of 246 [1.6%]; P = .04). CONCLUSIONS AND RELEVANCEIn patients with moderate to severe COVID-19 pneumonia, hightiter anti-SARS-CoV-2 CP did not reduce the progression to severe respiratory failure or death within 30 days. (continued) Key Points Question Is convalescent plasma useful in preventing worsening respiratory failure or death in patients with COVID-19 pneumonia? Findings In this randomized clinical trial of 487 patients with COVID-19 pneumonia and a partial pressure of arterial oxygen-to-fraction of inspired oxygen (PaO 2 /FiO 2 ) ratio between 350 and 200 mm Hg at enrollment, the rate of the primary clinical end point (need for mechanical ventilation, defined as PaO 2 /FiO 2 ratio <150 mm Hg, or death) was not significantly different between the convalescent plasma group and the control group. Meaning In this trial, convalescent plasma did not reduce the progression to severe respiratory failure or death within 30 days.

Introduction Different antivirals are available for the treatment of outpatients with COVID-19. Our aim was to describe a real-world experience of outpatient management of COVID-19 subjects at high risk of progression. Methods This prospective observational study conducted in the University Hospital of Pisa (January 2022–July 2022) included consecutive COVID-19 outpatients with at least one risk factor for disease progression. Patients received nirmatrelvir/ritonavir, molnupiravir, or 3-day remdesivir, according to the Italian Medicines Agency (AIFA) indications. All patients were followed up until 30 days from the first positive nasopharyngeal swab. The primary endpoint was a composite of death or hospitalization. Secondary endpoints were occurrence of adverse events and a negative test within 10 days from the first positive test. Multivariable analysis was performed to identify factors associated with death or hospitalization. Results Overall, 562 outpatients were included: 114 (20.3%) received molnupiravir, 252 (44.8%) nirmatrelvir/ritonavir, and 196 (34.9%) 3-day remdesivir. The composite endpoint occurred in 2.5% of patients and was more frequent in patients treated with remdesivir (5.1%) compared with molnupiravir (1.8%) or nirmatrelvir/ritonavir (0.8%, ANOVA among groups p = 0.012). On multivariable Cox regression analysis, presence of ≥ 3 comorbidities, hematological disease, gastrointestinal symptoms, and each-day increment from symptoms onset were factors associated with death or hospitalization, while antiviral treatment was not a predictor. Adverse events occurred more frequently in the nirmatrelvir/ritonavir group (49.2%). Nirmatrelvir/ritonavir compared with remdesivir was associated with a higher probability of having a negative test within 10 days from the first positive one. Conclusion Death or hospitalization did not differ among high-risk COVID-19 outpatients treated with currently available antivirals. Safety and time to a negative test differed among the three drugs. Supplementary Information The online version contains supplementary material available at 10.1007/s40121-022-00729-2.