Real-Life Assessment of the Ability of an Ultraviolet C Lamp (SanificaAria 200, Beghelli) to Inactivate Airborne Microorganisms in a Healthcare Environment.

Airborne-mediated microbial diseases represent one of the major challenges to public health. Ultraviolet C radiation (UVC) is among the different sanitation techniques useful to reduce the risk of infection in healthcare facilities. Previous studies about the germicidal activity of UVC were mainly performed in artificial settings or in vitro models. This study aimed to assess the sanitizing effectiveness of a UVC device (SanificaAria 200, Beghelli, Valsamoggia, Bologna, Italy) in 'real-life' conditions by evaluating its ability to reduce microbial loads in several hospital settings during routine daily activities. The efficacy of the UVC lamp in reducing the bacterial component was evaluated by microbial culture through the collection of air samples in different healthcare settings at different times (30 min-24 h) after turning on the device. To assess the anti-viral activity, air samplings were carried out in a room where a SARS-CoV-2-positive subject was present. The UVC device showed good antibacterial properties against a wide range of microbial species after 6 h of activity. It was effective against possible multi-drug resistant microorganisms (e.g., Pseudomonas spp., Acinetobacter spp.) and spore-forming bacteria (e.g., Bacillus spp.). In addition, the UVC lamp was able to inactivate SARS-CoV-2 in just one hour. Thanks to its effectiveness and safety, SanificaAria 200 could be useful to inactivate airborne pathogens and reduce health risks.

Long term follow-up of humoral and cellular response to mRNA-based vaccines for SARS-CoV-2 in patients with active multiple myeloma.

Long-term kinetics of antibody (Ab) and cell-mediated immune (CMI) response to full anti-SARS-CoV-2 vaccine schedule and booster doses in Multiple Myeloma (MM) patients remain unclear. We prospectively evaluated Ab and CMI response to mRNA vaccines in 103 SARS-CoV-2-naïve MM patients (median age 66, 1 median prior line of therapy) and 63 health-workers. Anti-S-RBD IgG (Elecsys®assay) were measured before vaccination and after 1 (T1), 3 (T3), 6 (T6), 9 (T9) and 12 (T12) months from second dose (D2) and 1 month after the introduction of the booster dose (T1D3). CMI response (IGRA test) was evaluated at T3 and T12. Fully vaccinated MM patients displayed high seropositivity rate (88.2%), but low CMI response (36.2%). At T6 the median serological titer was halved (p=0.0391) in MM patients and 35% reduced (p=0.0026) in controls. D3 (94 patients) increased the seroconversion rate to 99% in MM patients and the median IgG titer in both groups (up to 2500 U/mL), maintained at T12. 47% of MM patients displayed a positive CMI at T12 and double-negativity for humoral and CMI (9.6% at T3) decreased to 1%. Anti-S-RBD IgG level ≥346 U/mL showed 20-times higher probability of positive CMI response (OR 20.6, p<0.0001). Hematological response ≥CR and ongoing lenalidomide maintenance enhanced response to vaccination, hindered by proteasome inhibitors/anti-CD38 monoclonal antibodies. In conclusion, MM elicited excellent humoral, but insufficient cellular responses to anti-SARS-CoV-2 mRNA vaccines. Third dose improved immunogenicity renewal, even when undetectable after D2. Hematological response and ongoing treatment at vaccination were the main predictive factors of vaccine immunogenicity, emphasizing the role of vaccine response assessment to identify patients requiring salvage approaches.

Circulating extracellular particles from severe COVID-19 patients show altered profiling and innate lymphoid cell-modulating ability.

Introduction: Extracellular vesicles (EVs) and particles (EPs) represent reliable biomarkers for disease detection. Their role in the inflammatory microenvironment of severe COVID-19 patients is not well determined. Here, we characterized the immunophenotype, the lipidomic cargo and the functional activity of circulating EPs from severe COVID-19 patients (Co-19-EPs) and healthy controls (HC-EPs) correlating the data with the clinical parameters including the partial pressure of oxygen to fraction of inspired oxygen ratio (PaO2/FiO2) and the sequential organ failure assessment (SOFA) score. Methods: Peripheral blood (PB) was collected from COVID-19 patients (n=10) and HC (n=10). EPs were purified from platelet-poor plasma by size exclusion chromatography (SEC) and ultrafiltration. Plasma cytokines and EPs were characterized by multiplex bead-based assay. Quantitative lipidomic profiling of EPs was performed by liquid chromatography/mass spectrometry combined with quadrupole time-of-flight (LC/MS Q-TOF). Innate lymphoid cells (ILC) were characterized by flow cytometry after co-cultures with HC-EPs or Co-19-EPs. Results: We observed that EPs from severe COVID-19 patients: 1) display an altered surface signature as assessed by multiplex protein analysis; 2) are characterized by distinct lipidomic profiling; 3) show correlations between lipidomic profiling and disease aggressiveness scores; 4) fail to dampen type 2 innate lymphoid cells (ILC2) cytokine secretion. As a consequence, ILC2 from severe COVID-19 patients show a more activated phenotype due to the presence of Co-19-EPs. Discussion: In summary, these data highlight that abnormal circulating EPs promote ILC2-driven inflammatory signals in severe COVID-19 patients and support further exploration to unravel the role of EPs (and EVs) in COVID-19 pathogenesis.

Using machine learning to predict antibody response to SARS-CoV-2 vaccination in solid organ transplant recipients: the multicentre ORCHESTRA cohort.

OBJECTIVES: The study aim was to assess predictors of negative antibody response (AbR) in solid organ transplant (SOT) recipients after the first booster of SARS-CoV-2 vaccination. METHODS: Solid organ transplant recipients receiving SARS-CoV-2 vaccination were prospectively enrolled (March 2021-January 2022) at six hospitals in Italy and Spain. AbR was assessed at first dose (t0), second dose (t1), 3 ± 1 month (t2), and 1 month after third dose (t3). Negative AbR at t3 was defined as an anti-receptor binding domain titre <45 BAU/mL. Machine learning models were developed to predict the individual risk of negative (vs. positive) AbR using age, type of transplant, time between transplant and vaccination, immunosuppressive drugs, type of vaccine, and graft function as covariates, subsequently assessed using a validation cohort. RESULTS: Overall, 1615 SOT recipients (1072 [66.3%] males; mean age±standard deviation [SD], 57.85 ± 13.77) were enrolled, and 1211 received three vaccination doses. Negative AbR rate decreased from 93.66% (886/946) to 21.90% (202/923) from t0 to t3. Univariate analysis showed that older patients (mean age, 60.21 ± 11.51 vs. 58.11 ± 13.08), anti-metabolites (57.9% vs. 35.1%), steroids (52.9% vs. 38.5%), recent transplantation (<3 years) (17.8% vs. 2.3%), and kidney, heart, or lung compared with liver transplantation (25%, 31.8%, 30.4% vs. 5.5%) had a higher likelihood of negative AbR. Machine learning (ML) algorithms showing best prediction performance were logistic regression (precision-recall curve-PRAUC mean 0.37 [95%CI 0.36-0.39]) and k-Nearest Neighbours (PRAUC 0.36 [0.35-0.37]). DISCUSSION: Almost a quarter of SOT recipients showed negative AbR after first booster dosage. Unfortunately, clinical information cannot efficiently predict negative AbR even with ML algorithms.

Relationship Between Immune Response to Severe Acute Respiratory Syndrome Coronavirus 2 Vaccines and Development of Breakthrough Infection in Solid Organ Transplant Recipients: The CONTRAST Cohort.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in solid organ transplant (SOT) recipients is associated with poorer antibody response (AbR) compared with non-SOT recipients. However, its impact on the risk of breakthrough infection (BI) has yet to be assessed. METHODS: Single-center prospective longitudinal cohort study enrolling adult SOT recipients who received SARS-CoV-2 vaccination during a 1-year period (February 2021 - January 2022), end of follow-up April 2022. Patients were tested for AbR at multiple time points. The primary end-point was BI (laboratory-confirmed SARS-CoV-2 infection ≥14 days after the second dose). Immunization (positive AbR) was considered an intermediate state between vaccination and BI. Probabilities of being in vaccination, immunization, and BI states were obtained for each type of graft and vaccination sequence using multistate survival analysis. Then, multivariable logistic regression was performed to analyze the risk of BI related to AbR levels. RESULTS: 614 SOT (275 kidney, 163 liver, 137 heart, 39 lung) recipients were included. Most patients (84.7%) received 3 vaccine doses. The first 2 consisted of BNT162b2 and mRNA-1273 in 73.5% and 26.5% of cases, respectively. For the third dose, mRNA-1273 was administered in 59.8% of patients. Overall, 75.4% of patients reached immunization and 18.4% developed BI. Heart transplant recipients showed the lowest probability of immunization (0.418) and the highest of BI (0.323); all mRNA-1273 vaccine sequences showed the highest probability of immunization (0.732) and the lowest of BI (0.098). Risk of BI was higher for non-high-level AbR, younger age, and shorter time from transplant. CONCLUSIONS: SOT patients with non-high-level AbR and shorter time from transplantation and heart recipients are at highest risk of BI.

Environmental Contamination by SARS-CoV-2 During Noninvasive Ventilation in COVID-19.

BACKGROUND: Environmental contamination by SARS-CoV-2 from patients with COVID-19 undergoing noninvasive ventilation (NIV) in the ICU is still under investigation. This study set out to investigate the presence of SARS-CoV-2 on surfaces near subjects receiving NIV in the ICU under controlled conditions (ie, use of dual-limb circuits, filters, adequate room ventilation). METHODS: This was a single-center, prospective, observational study in the ICU of a tertiary teaching hospital. Four surface sampling areas, at increasing distance from subject's face, were identified; and each one was sampled at fixed intervals: 6, 12, and 24 h. The presence of SARS-CoV-2 was detected with real-time reverse transcriptase-polymerase-chain-reaction (RT-PCR) test on environmental swabs; the RT-PCR assay targeted the SARS-CoV-2 virus nucleocapsid N1 and N2 genes and the human RNase P gene as internal control. RESULTS: In a total of 256 collected samples, none were positive for SARS-CoV-2 genetic material, whereas 21 samples (8.2%) tested positive for RNase P, thus demonstrating the presence of genetic material unrelated to SARS-CoV-2. CONCLUSIONS: Our data show that application of NIV in an appropriate environment and with correct precautions leads to no sign of surface environmental contamination. Accordingly, our data support the idea that use of NIV in the ICU is safe both for health care workers and for other patients.

Virological and histological evaluation of intestinal samples in COVID-19 patients.

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the pathogen responsible for pandemic coronavirus disease 2019 (COVID-19). It is a highly contagious virus which primarily affects the respiratory tract, nevertheless, the lungs are not the only target organs of the virus. The intestinal tract could represent an additional tropism site for SARS-CoV-2. Several observations have collectively suggested that enteric infections can occur in COVID-19 patients. However, the detection of viral RNA in gastrointestinal (GI) tissue samples has not been adequately investigated and results are conflicting. AIM: To detect the presence of SARS-CoV-2 RNA in intestinal mucosa samples and to evaluate histological features. METHODS: The COVID-19 patients hospitalized at an Italian tertiary hospital from April 2020 to March 2021 were evaluated for enrollment in an observational, monocentric trial. The study population was composed of two groups of adult patients. In the first group (biopsy group, 30 patients), patients were eligible for inclusion if they had mild to moderate disease and if they agreed to have a rectal biopsy; in the second group (surgical specimen group, 6 patients), patients were eligible for inclusion if they underwent intestinal resection during index hospitalization. Fifty-nine intestinal mucosal samples were analyzed. RESULTS: Viral RNA was not detectable in any of the rectal biopsies performed (0/53). Histological examination showed no enterocyte damage, but slight edema of the lamina propria with mild inflammatory lymphoplasmacytic infiltration. There was no difference in inflammatory infiltrates in patients with and without GI symptoms. SARS-CoV-2 RNA was detected in fecal samples in 6 cases out of 14 cases examined (42.9%). In the surgical specimen group, all patients underwent emergency intestinal resection. Viral RNA was detected in 2 surgical specimens of the 6 examined, both of which were from patients with active neoplastic disease. Histological examination also pointed out abundant macrophages, granulocytes and plasma cells infiltrating the muscular layer and adipose tissue, and focal vasculitis. CONCLUSION: Mild-moderate COVID-19 may not be associated with rectal infection by the virus. More comprehensive autopsies or surgical specimens are needed to provide histological evidence of intestinal infection.

Evaluation of humoral and cellular response to four vaccines against COVID-19 in different age groups: A longitudinal study.

To date there has been limited head-to-head evaluation of immune responses to different types of COVID-19 vaccines. A real-world population-based longitudinal study was designed with the aim to define the magnitude and duration of immunity induced by each of four different COVID-19 vaccines available in Italy at the time of this study. Overall, 2497 individuals were enrolled at time of their first vaccination (T0). Vaccine-specific antibody responses induced over time by Comirnaty, Spikevax, Vaxzevria, Janssen Ad26.COV2.S and heterologous vaccination were compared up to six months after immunization. On a subset of Comirnaty vaccinees, serology data were correlated with the ability to neutralize a reference SARS-CoV-2 B strain, as well as Delta AY.4 and Omicron BA.1. The frequency of SARS-CoV-2-specific CD4+ T cells, CD8+ T cells, and memory B cells induced by the four different vaccines was assessed six months after the immunization. We found that mRNA vaccines are stronger inducer of anti-Spike IgG and B-memory cell responses. Humoral immune responses are lower in frail elderly subjects. Neutralization of the Delta AY.4 and Omicron BA.1 variants is severely impaired, especially in older individuals. Most vaccinees display a vaccine-specific T-cell memory six months after the vaccination. By describing the immunological response during the first phase of COVID-19 vaccination campaign in different cohorts and considering several aspects of the immunological response, this study allowed to collect key information that could facilitate the implementation of effective prevention and control measures against SARS-CoV-2.

Infants Born Following SARS-CoV-2 Infection in Pregnancy.

OBJECTIVES: To evaluate outcomes of neonates born to mothers with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during pregnancy, the dynamics of placental transfer of maternal antibodies, and its persistence during infancy. METHODS: Cohort study enrolling neonates born to mothers with SARS-CoV-2 infection in pregnancy. All infants were evaluated at birth. Those born to women with infection onset within 2 weeks before delivery were excluded from further analyses. Remaining infants underwent cerebral and abdominal ultrasound, fundoscopy evaluation, and were enrolled in a 12 month follow-up. Qualitative immunoglobulin G (IgG)/immunoglobulin M and quantitative IgG to S1/S2 subunits of spike protein were assessed in mother-neonate dyads within 48 hours postdelivery and during follow-up. RESULTS: Between April 2020 and April 2021, 130 of 2745 (4.7%) neonates were born to mothers with SARS-CoV-2 infection in pregnancy, with 106 of 130 infections diagnosed before 2 weeks before delivery. Rates of preterm and cesarean delivery were comparable between women with and without infection (6% vs 8%, P = .57; 22% vs 32%, P = .06). No clinical or instrumental abnormalities were detected at birth or during follow-up. There was a positive correlation between maternal and neonatal SARS-CoV-2 IgG levels (r = 0.81, P < .001). Transplacental transfer ratio was higher after second-trimester maternal infections as compared with first and third trimester (P = .03). SARS-CoV-2 IgG level progressively decreased in all infants, with 89 of 92 (97%) infants seronegative at 6 months of age. CONCLUSIONS: Clinical outcomes were favorable in all infants. Matching peak IgG level after infection and higher IgG transplacental transfer might result in the most durable neonatal passive immunity.

Difference in safety and humoral response to mRNA SARS-CoV-2 vaccines in patients with autoimmune neurological disorders: the ANCOVAX study.

BACKGROUND: Assessing the safety of SARS-CoV-2 mRNA vaccines and the effect of immunotherapies on the seroconversion rate in patients with autoimmune neurological conditions (ANC) is relevant to clinical practice. Our aim was to assess the antibody response to and safety of SARS-CoV-2 mRNA vaccines in ANC. METHODS: This longitudinal study included ANC patients vaccinated with two doses of BNT162b2 or mRNA-1273 between March and August 2021. Side effects were assessed 2-10 days after each dose. Neurological status and anti-spike receptor binding domain antibody levels were evaluated before vaccination and 4 weeks after the second dose. Healthcare-workers served as controls for antibody levels. RESULTS: We included 300 ANC patients (median age 52, IQR 40-65), and 347 healthcare-workers (median age 45, IQR 34-54). mRNA-1273 vaccine was associated with an increased risk of both local (OR 2.52 95% CI 1.45-4.39, p = 0.001) and systemic reactions (OR 2.51% CI 1.49-4.23, p = 0.001). The incidence of relapse was not different before and after vaccine (Incidence rate ratio 0.72, 95% CI 0.29-1.83). Anti-SARS-CoV-2 IgG were detected in 268 (89.9%) patients and in all controls (p < 0.0001). BNT162b2 vaccine (OR 8.84 95% CI 2.32-33.65, p = 0.001), anti-CD20 mAb (OR 0.004 95% CI 0.0007-0.026, p < 0.0001) and fingolimod (OR 0.036 95% CI 0.002-0.628, p = 0·023) were associated with an increased risk of not developing anti-SARS-CoV-2 IgG. CONCLUSION: SARS-CoV-2 mRNA vaccines were safe in a large group of ANC patients. Anti-CD20 and fingolimod treatment, as well as vaccination with the BNT162b2 vaccine, led to a reduced humoral response. These findings could inform vaccine policies in ANC patients undergoing immunotherapy.

Critically ill patients with COVID-19 show lung fungal dysbiosis with reduced microbial diversity in patients colonized with Candida spp.

BACKGROUND: The COVID-19 pandemic has intensified interest in how the infection affects the lung microbiome of critically ill patients and how it contributes to acute respiratory distress syndrome (ARDS). We aimed to characterize the lower respiratory tract mycobiome of critically ill patients with COVID-19 in comparison to patients without COVID-19. METHODS: We performed an internal transcribed spacer 2 (ITS2) profiling with the Illumina MiSeq platform on 26 respiratory specimens from patients with COVID-19 as well as from 26 patients with non-COVID-19 pneumonia. RESULTS: Patients with COVID-19 were more likely to be colonized with Candida spp. ARDS was associated with lung dysbiosis characterized by a shift to Candida species colonization and a decrease of fungal diversity. We also observed higher bacterial phylogenetic distance among taxa in colonized patients with COVID-19. In patients with COVID-19 not colonized with Candida spp., ITS2 amplicon sequencing revealed an increase of Ascomycota unassigned spp. and 1 Aspergillus spp.-positive specimen. In addition, we found that corticosteroid therapy was frequently associated with positive Galactomannan cell wall component of Aspergillus spp. among patients with COVID-19. CONCLUSION: Our study underpins that ARDS in patients with COVID-19 is associated with lung dysbiosis and that an increased density of Ascomycota unassigned spp. is present in patients not colonized with Candida spp.

Evaluation of the Kinetics of Antibody Response to COVID-19 Vaccine in Solid Organ Transplant Recipients: The Prospective Multicenter ORCHESTRA Cohort.

Previous studies assessing the antibody response (AbR) to mRNA COVID-19 vaccines in solid organ transplant (SOT) recipients are limited by short follow-up, hampering the analysis of AbR kinetics. We present the ORCHESTRA SOT recipients cohort assessed for AbR at first dose (t0), second dose (t1), and within 3 ± 1 month (t2) after the first dose. We analyzed 1062 SOT patients (kidney, 63.7%; liver, 17.4%; heart, 16.7%; and lung, 2.5%) and 5045 health care workers (HCWs). The AbR rates in the SOTs and HCWs were 52.3% and 99.4%. The antibody levels were significantly higher in the HCWs than in the SOTs (p < 0.001). The kinetics showed an increase (p < 0.001) in antibody levels up to 76 days and a non-significant decrease after 118 days in the SOT recipients versus a decrease up to 76 days (p = 0.02) and a less pronounced decrease between 76 and 118 days (p = 0.04) in the HCWs. Upon multivariable analysis, liver transplant, ≥3 years from SOT, mRNA-1273, azathioprine, and longer time from t0 were associated with a positive AbR at t2. Older age, other comorbidities, mycophenolate, steroids, and impaired graft function were associated with lower AbR probability. Our results may be useful to optimize strategies of immune monitoring after COVID-19 vaccination and indications regarding timing for booster dosages calibrated on SOT patients' characteristics.

COVID-19 and the Brain: The Neuropathological Italian Experience on 33 Adult Autopsies.

Neurological symptoms are increasingly recognized in SARS-CoV-2 infected individuals. However, the neuropathogenesis remains unclear and it is not possible to define a specific damage pattern due to brain virus infection. In the present study, 33 cases of brain autopsies performed during the first (February-April 2020) and the second/third (November 2020-April 2021) pandemic waves are described. In all the cases, SARS-CoV-2 RNA was searched. Pathological findings are described and compared with those presently published.

Severe neonatal COVID-19: Challenges in management and therapeutic approach.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of coronavirus disease 2019 (COVID-19), may manifest as a life-threatening respiratory infection with systemic complications. Clinical manifestations among children are generally less severe than those seen in adults, but critical cases have increasingly been reported in infants less than 1 year of age. We report a severe case of neonatal COVID-19 requiring intensive care and mechanical ventilation, further complicated by a multidrug-resistant Enterobacter asburiae super-infection. Chest X-rays, lung ultrasound, and chest computed tomography revealed extensive interstitial pneumonia with multiple consolidations, associated with persistent increased work of breathing and feeding difficulties. SARS-CoV-2 RNA was detected in respiratory specimens and stools, but not in other biological samples, with a rapid clearance in stools. Serological tests demonstrated a specific SARS-CoV-2 antibody response mounted by the neonate and sustained over time. The therapeutic approach included the use of enoxaparin and steroids which may have contributed to the bacterial complication, underlying the challenges in managing neonatal COVID-19, where the balance between viral replication and immunomodulation maybe even more challenging than in older ages.

Feasibility and Effectiveness Assessment of SARS-CoV-2 Antigenic Tests in Mass Screening of a Pediatric Population and Correlation with the Kinetics of Viral Loads.

The gold standard for diagnosis of SARS-CoV-2 infection has been nucleic acid amplification tests (NAAT). However, rapid antigen detection kits (Ag-RDTs), may offer advantages over NAAT in mass screening, generating results in minutes, both as laboratory-based test or point-of-care (POC) use for clinicians, at a lower cost. We assessed two different POC Ag-RDTs in mass screening versus NAAT for SARS-CoV-2 in a cohort of pediatric patients admitted to the Pediatric Emergency Unit of IRCCS-Polyclinic of Sant'Orsola, Bologna (from November 2020 to April 2021). All patients were screened with nasopharyngeal swabs for the detection of SARS-CoV-2-RNA and for antigen tests. Results were obtained from 1146 patients. The COVID-19 Ag FIA kit showed a baseline sensitivity of 53.8% (CI 35.4-71.4%), baseline specificity 99.7% (CI 98.4-100%) and overall accuracy of 80% (95% CI 0.68-0.91); the AFIAS COVID-19 Ag kit, baseline sensitivity of 86.4% (CI 75.0-93.9%), baseline specificity 98.3% (CI 97.1-99.1%) and overall accuracy of 95.3% (95% CI 0.92-0.99). In both tests, some samples showed very low viral load and negative Ag-RDT. This disagreement may reflect the positive inability of Ag-RDTs of detecting antigen in late phase of infection. Among all cases with positive molecular test and negative antigen test, none showed viral loads > 106 copies/mL. Finally, we found one false Ag-RDTs negative result (low cycle thresholds; 9 × 105 copies/mL). Our results suggest that both Ag-RDTs showed good performances in detection of high viral load samples, making it a feasible and effective tool for mass screening in actively infected children.

Spectrum of Cardiovascular Diseases in Children During High Peak Coronavirus Disease 2019 Period Infection in Northern Italy: Is There a Link?

BACKGROUND: Children with coronavirus disease-2019 (COVID-19) have a milder clinical course than adults. We describe the spectrum of cardiovascular manifestations during a COVID-19 outbreak in Emilia-Romagna, Italy. METHODS: A cross-sectional multicenter study was performed, including all patients diagnosed with Kawasaki disease (KD), myocarditis, and multisystem inflammatory syndrome in children (MIS-C) from February to April 2020. KD patients were compared with those diagnosed before the epidemic. RESULTS: KD: 8 patients (6/8 boys, all negative for severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2]): complete presentation in 5/8, 7/8 immunoglobulin (IVIG) responders, and 3/8 showed transient coronary lesions (CALs). Myocarditis: one 5-year-old girl negative for SARS-CoV-2 and positive for parvovirus B19. She responded to IVIG. MIS-C: 4 SARS-CoV-2-positive boys (3 patients with positive swab and serology and 1 patient with negative swab and positive serology): 3 presented myocardial dysfunction and pericardial effusion, and 1 developed multicoronary aneurysms and hyperinflammation; all responded to treatment. The fourth boy had mitral and aortic regurgitation that rapidly regressed after steroids. CONCLUSIONS: KD, myocarditis, and MIS-C were distinguishable cardiovascular manifestations. KD did not show a more aggressive form compared with previous years: coronary involvement was frequent but always transient. MIS-C and myocarditis rapidly responded to treatment without cardiac sequelae despite high markers of myocardial injury at the onset, suggesting a myocardial depression due to systemic inflammation rather than focal necrosis. Evidence of actual or previous SARS-CoV-2 infection was documented only in patients with MIS-C.

Respiratory bacterial co-infections in intensive care unit-hospitalized COVID-19 patients: Conventional culture vs BioFire FilmArray pneumonia Plus panel.

The prevalence and microbiology of concomitant respiratory bacterial infections in patients with SARS-CoV-2 infection are not yet fully understood. In this retrospective study, we assessed respiratory bacterial co-infections in lower respiratory tract samples taken from intensive care unit-hospitalized COVID-19 patients, by comparing the conventional culture approach to an innovative molecular diagnostic technology. A total of 230 lower respiratory tract samples (i.e., bronchial aspirates or bronchoalveolar lavages) were taken from 178 critically ill COVID-19 patients. Each sample was processed by a semi-quantitative culture and by a multiplex PCR panel (FilmArray Pneumonia Plus panel), allowing rapid detection of a wide range of clinically relevant pathogens and a limited number of antimicrobial resistance markers. More than 30% of samples showed a positive bacterial culture, with Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus the most detected pathogens. FilmArray showed an overall sensitivity and specificity of 89.6% and 98.3%, respectively, with a negative predictive value of 99.7%. The molecular test significantly reduced the turn-around-time (TAT) and increased the rates of microbial detection. Most cases missed by culture were characterized by low bacterial loads (104-105 copies/mL). FilmArray missed a list of pathogens not included in the molecular panel, especially Stenotrophomonas maltophilia (8 cases). FilmArray can be useful to detect bacterial pathogens in lower respiratory tract specimens of COVID-19 patients, with a significant decrease of TAT. The test is particularly useful to rule out bacterial co-infections and avoid the inappropriate prescription of antibiotics.