Natural killer-cell immunoglobulin-like receptors trigger differences in immune response to SARS-CoV-2 infection.

BACKGROUND: The diversity in the clinical course of COVID-19 has been related to differences in innate and adaptative immune response mechanisms. Natural killer (NK) lymphocytes are critical protagonists of human host defense against viral infections. It would seem that reduced circulating levels of these cells have an impact on COVID-19 progression and severity. Their activity is strongly regulated by killer-cell immuno-globulin-like receptors (KIRs) expressed on the NK cell surface. The present study's focus was to investigate the impact of KIRs and their HLA Class I ligands on SARS-CoV-2 infection. METHODS: KIR gene frequencies, KIR haplotypes, KIR ligands and combinations of KIRs and their HLA Class I ligands were investigated in 396 Sardinian patients with SARS-CoV-2 infection. Comparisons were made between 2 groups of patients divided according to disease severity: 240 patients were symptomatic or paucisymptomatic (Group A), 156 hospitalized patients had severe disease (Group S). The immunogenetic characteristics of patients were also compared to a population group of 400 individuals from the same geographical areas. RESULTS: Substantial differences were obtained for KIR genes, KIR haplotypes and KIR-HLA ligand combinations when comparing patients of Group S to those of Group A. Patients in Group S had a statistically significant higher frequency of the KIR A/A haplotype compared to patients in Group A [34.6% vs 23.8%, OR = 1.7 (95% CI 1.1-2.6); P = 0.02, Pc = 0.04]. Moreover, the KIR2DS2/HLA C1 combination was poorly represented in the group of patients with severe symptoms compared to those of the asymptomatic-paucisymptomatic group [33.3% vs 50.0%, OR = 0.5 (95% CI 0.3-0.8), P = 0.001, Pc = 0.002]. Multivariate analysis confirmed that, regardless of the sex and age of the patients, the latter genetic variable correlated with a less severe disease course [ORM = 0.4 (95% CI 0.3-0.7), PM = 0.0005, PMC = 0.005]. CONCLUSIONS: The KIR2DS2/HLA C1 functional unit resulted to have a strong protective effect against the adverse outcomes of COVID-19. Combined to other well known factors such as advanced age, male sex and concomitant autoimmune diseases, this marker could prove to be highly informative of the disease course and thus enable the timely intervention needed to reduce the mortality associated with the severe forms of SARS-CoV-2 infection. However, larger studies in other populations as well as experimental functional studies will be needed to confirm our findings and further pursue the effect of KIR receptors on NK cell immune-mediated response to SARS-Cov-2 infection.

Human Leukocyte Antigen Complex and Other Immunogenetic and Clinical Factors Influence Susceptibility or Protection to SARS-CoV-2 Infection and Severity of the Disease Course. The Sardinian Experience.

Aim: SARS-CoV-2 infection is a world-wide public health problem. Several aspects of its pathogenesis and the related clinical consequences still need elucidation. In Italy, Sardinia has had very low numbers of infections. Taking advantage of the low genetic polymorphism in the Sardinian population, we analyzed clinical, genetic and immunogenetic factors, with particular attention to HLA class I and II molecules, to evaluate their influence on susceptibility to SARS-CoV-2 infection and the clinical outcome. Method and Materials: We recruited 619 healthy Sardinian controls and 182 SARS-CoV-2 patients. Thirty-nine patients required hospital care and 143 were without symptoms, pauci-symptomatic or with mild disease. For all participants, we collected demographic and clinical data and analyzed the HLA allele and haplotype frequencies. Results: Male sex and older age were more frequent in hospitalized patients, none of whom had been vaccinated during the previous seasonal flu vaccination campaignes. Compared to the group of asymptomatic or pauci-symptomatic patients, hospitalized patients also had a higher frequency of autoimmune diseases and glucose-6-phosphate-dehydrogenase (G6PDH) deficiency. None of these patients carried the beta-thalassemia trait, a relatively common finding in the Sardinian population. The extended haplotype HLA-A*02:05, B*58:01, C*07:01, DRB1*03:01 [OR 0.1 (95% CI 0-0.6), Pc = 0.015] was absent in all 182 patients, while the HLA-C*04:01 allele and the three-loci haplotype HLA-A*30:02, B*14:02, C*08:02 [OR 3.8 (95% CI 1.8-8.1), Pc = 0.025] were more frequently represented in patients than controls. In a comparison between in-patients and home care patients, the HLA-DRB1*08:01 allele was exclusively present in the hospitalized patients [OR > 2.5 (95% CI 2.7-220.6), Pc = 0.024]. Conclusion: The data emerging from our study suggest that the extended haplotype HLA-A*02:05, B*58:01, C*07:01, DRB1*03:01 has a protective effect against SARS-CoV-2 infection in the Sardinian population. Genetic factors that resulted to have a negative influence on the disease course were presence of the HLA-DRB1*08:01 allele and G6PDH deficiency, but not the beta-thalassemic trait. Absence of influenza vaccination could be a predisposing factor for more severe disease.

[Hypnosis in transesophageal echocardiography. The experience in a Pediatric Cardiology and Congenital Heart Disease Unit]. / L'ipnosi nell'ecocardiografia transesofagea. L'esperienza di un Centro di Cardiologia Pediatrica e delle Cardiopatie Congenite.

BACKGROUND: The purpose of this study was to use hypnosis in patients with congenital heart disease undergoing transesophageal echocardiography (TEE). METHODS: From January 2016 to July 2017, 50 adult patients undergoing TEE were randomly assigned to two groups: TEE in hypnosis (n = 23), TEE in sedation (n = 27). Vital parameters (heart rate [HR], blood pressure [BP], oxygen saturation [SO2] before, during and after the procedure) and drug administration were recorded. The State-Trait Anxiety Inventory was performed before and after TEE, the memory and experience of TEE through a structured interview were assessed. RESULTS: All patients in the hypnosis group performed TEE without any sedation. As for anxiety before TEE, no significant differences were observed between groups; after TEE all patients were less anxious than at the beginning (p<0.001) with a greater decrease in patients of the hypnosis group (p<0.001). Before TEE, there were no significant differences also in HR, BP and SO2. During TEE in both groups a similar increase in HR and BP was found (p<0.001), whereas SO2 values remained stable. In the responses to the structured interview, 94% of patients in the sedation group remembered everything vs 36% of the hypnosis group (p<0.05). No differences were found in the other answers between the two groups. CONCLUSIONS: Hypnosis in TEE is useful to improve the emotional experience of patients with congenital heart disease.

[Accurate compiling of the hospital discharge records according to clinicians' perception: critical issues and perspectives]. / L'accurata compilazione delle schede di dimissione ospedaliera secondo la percezione dei medici: criticità e prospettive.

OBJECTIVES: to explore clinicians vision on hospital discharge records in order to identify useful elements to foster a more accurate compiling. DESIGN: qualitative research with phenomenological approach. SETTING AND PARTICIPANTS: participants were selected through purposive sampling among clinicians of two hospitals located in Sardinia; the sample included 76 people (32 medical directors and 44 doctors in training). MAIN OUTCOME MEASURES: identified codes for themes under investigation: vision of accurate compiling, difficulties, and proposals. RESULTS: collected data highlighted two prevailing visions, respectively focused on the importance of an accurate compiling and on the burden of such activity. The accurate compiling is hindered by the lack of motivation and training, by the limits of the registration system and the information technology, by the distortions induced by the prominent role of the hospital discharge records in the evaluation processes. Training, timely updating of the information system accompanied by a proper cross-cultural validation process, improvement of the computer system, and activation of support services could promote more accurate compiling. CONCLUSIONS: the implementation of services, unconnected with evaluation and control processes, dedicated to training and support in the compiling of the hospital discharge records and in the conduction of related epidemiological studies would facilitate the compliance to the compilation. Such services will make tangible the benefits obtainable from this registration system, increasing skills, motivation, ownership, and facilitating greater accuracy in compiling.

Healthcare-associated respiratory infections in intensive care unit can be reduced by a hand hygiene program: A multicenter study.

PURPOSE: Healthcare-associated respiratory tract infections are common and markedly affect the quality of life and mortality, as well as increasing costs for health systems due to prolonged hospitalisation. This study aimed to assess the change in both level and trend of respiratory tract infections after a specific hand hygiene program for intensive care unit (ICU) staff. MATERIALS AND METHODS: The infection data collection was carried out from January 2013 to August 2014. The hand hygiene program started in December 2013. To analyse the change in level and trend of infections after the intervention, the Interrupted Time Series method was used. Chi-square test was used to compare the incidence of respiratory tract infections before and after the intervention. RESULTS: A total of 825 patients were hospitalised in three Italian ICUs. The infection level was significantly decreased by 36.3 infections per 1000 device-days after the intervention. The infection trend was also decreased of about 1 infection per month. CONCLUSIONS: After the hand hygiene program a decreased level of infection was found. Continuous performance feedback should be provided to promote a long-term adherence to the guidelines. Organisational and individual risk factors must be individuated and correctly managed to increase quality of practice.

Pattern of Hepatitis A Virus Epidemiology in Nursing Students and Adherence to Preventive Measures at Two Training Wards of a University Hospital.

BACKGROUND: Nursing students can be exposed to patients with hepatitis A virus (HAV) and can represent a vehicle of transmission both for health personnel, patients and relatives. OBJECTIVES: The aim of this study was to assess the risk of HAV infection in nursing students during their internship. PATIENTS AND METHODS: A seroprevalence survey on HAV infection was performed on nursing students at the Cagliari university-hospital, together with the assessment of the compliance to preventive measures to decrease the risk of infection during their internship. Blood specimens were obtained from 253 students. All serum samples were tested for anti-HAV antibodies (IgG) by the enzyme-linked immunosorbent assay (ELISA). Compliance to preventive measures was recorded by trained personnel. RESULTS: Overall HAV seropositivity in nursing students (mean age 24, range 17 - 45 years) was 3%. Compliance to preventive measures was not uniform (6% - 76%) and extremely low in some specific measures targeted to decrease the oral-fecal transmission. CONCLUSIONS: The high proportion of susceptible nursing students can contribute to an increase in the risk of nosocomial transmission, especially when specific preventive measures are not completely applied. Nursing education packages, before starting medical internship, should be implemented in order to increase their compliance to preventive measures, especially in wards at higher risk. Vaccination should be considered in wards at higher risk.