The global prevalence of methicillin-resistant Staphylococcus aureus colonization in residents of elderly care centers: a systematic review and meta-analysis.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a difficult to treat infection, particularly in residents of elderly care centers (ECCs). Despite the substantial burden of MRSA, an inadequate number of studies have analyzed MRSA prevalence in ECCs. OBJECTIVES: We conducted a worldwide systematic review and meta-analysis on the prevalence and risk factors of MRSA in ECCs. METHODS: We searched MEDLINE/PubMed, EMBASE, Web of Science, and Scopus databases and the gray literature sources for all studies published between January 1980 and December 2022 on the prevalence of MRSA in ECCs. A random-effects model was utilized to estimate pooled prevalence rates at 95% confidence intervals (CI). Moreover, the data were analyzed based on World Health Organization-defined regions, income, and human development index levels. RESULTS: In total, 119 studies, including 164,717 participants from 29 countries, were found eligible for meta-analysis. The pooled global prevalence of MRSA was 14.69% (95% CI 12.39-17.15%; 16,793/164,717). Male gender [prevalence ratio (PR) = 1.55; 95% CI 1.47-1.64], previous MRSA infection (PR = 3.71; 95% CI 3.44-4.01), prior use of antibiotics (PR = 1.97; 95% CI 1.83-2.12), hospitalized within the previous year (PR = 1.32; 95% CI 1.20-1.45), have had any wound (PR = 2.38; 95% CI 2.23-2.55), have used urinary catheter (PR = 2.24; 95% CI 2.06-2.43), have used any medical device (PR = 1.78; 95% CI 1.66-1.91), and those with diabetes (PR = 1.55; CI 1.43-1.67) were more likely to be colonized by MRSA than other patients. CONCLUSION: Screening programs and preventive measures should target MRSA in ECCs due to the high global prevalence rates.

TP53 Gene 72 Arg/Pro (rs1042522) single nucleotide polymorphism increases the risk and the severity of chronic lymphocytic leukemia.

Background: Genetic variations in TP53 gene are known to be important in chronic lymphocytic leukemia (CLL) and may cause its inactivation which is associated with an aggressive form of the disease. Single nucleotide polymorphism (rs1042522:G>C) in TP53 gene at codon 72 encodes for arginine (Arg) or proline (Pro) variant which results in amino acid substitution affecting the apoptotic potential of TP53 protein. The aim of this study was to assess the correlation between TP53 codon 72 polymorphism and risk susceptibility as well as severity of CLL among Tunisian patients. Materials and methods: A case-control study was conducted in Tunisia from February 2019 to November 2021, 160 de novo CLL patients and 160 healthy volunteers matched in age and gender were involved. DNA was extracted from peripheral blood mononuclear cells and the rs1042522 was analyzed using PCR-RFLP. Results: Pro variant was associated with higher susceptibility to CLL than Arg variant (p= 0.023). A significant association was found between Pro variant and prognostic classification of Binet stage C (p= 0.001), low hemoglobin level (p= 0.003) and low platelet count (p= 0.016). Conclusion: We suggest that Pro variant may increase the risk of developing CLL in our population and could be associated with the severity of the disease.

SARS-CoV-2 seroprevalence in children worldwide: A systematic review and meta-analysis.

Background: The higher hospitalisation rates of those aged 0-19 years (referred to herein as 'children') observed since the emergence of the immune-evasive SARS-CoV-2 Omicron variant and subvariants, along with the persisting vaccination disparities highlighted a need for in-depth knowledge of SARS-CoV-2 sero-epidemiology in children. Here, we conducted this systematic review to assess SARS-CoV-2 seroprevalence and determinants in children worldwide. Methods: In this systematic review and meta-analysis study, we searched international and preprinted scientific databases from December 1, 2019 to July 10, 2022. Pooled seroprevalences were estimated according to World Health Organization (WHO) regions (at 95% confidence intervals, CIs) using random-effects meta-analyses. Associations with SARS-CoV-2 seroprevalence and sources of heterogeneity were investigated using sub-group and meta-regression analyses. The protocol used in this study has been registered in PROSPERO (CRD42022350833). Findings: We included 247 studies involving 757,075 children from 70 countries. Seroprevalence estimates varied from 7.3% (5.8-9.1%) in the first wave of the COVID-19 pandemic to 37.6% (18.1-59.4%) in the fifth wave and 56.6% (52.8-60.5%) in the sixth wave. The highest seroprevalences in different pandemic waves were estimated for South-East Asia (17.9-81.8%) and African (17.2-66.1%) regions; while the lowest seroprevalence was estimated for the Western Pacific region (0.01-1.01%). Seroprevalence estimates were higher in children at older ages, in those living in underprivileged countries or regions, and in those of minority ethnic backgrounds. Interpretation: Our findings indicate that, by the end of 2021 and before the Omicron wave, around 50-70% of children globally were still susceptible to SARS-CoV-2 infection, clearly emphasising the need for more effective vaccines and better vaccination coverage among children and adolescents, particularly in developing countries and minority ethnic groups. Funding: None.

EZH2, new diagnosis and prognosis marker in acute myeloid leukemia patients.

PURPOSE: Acute myeloid leukemia (AML) is a heterogeneous disease. The discovery of novel discriminative biomarkers remains of utmost value for improving outcome predictions. Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase of H3K27me3. It is frequently up-regulated in human cancers and associated with silencing of differentiation genes. We aimed herein to investigate the prevalence and prognosis impact of somatic EZH2 mutations and their potential associations with other prognostic markers FLT3, NPM1, DNMT3A and IDH2. MATERIALS AND METHODS: Our study population was composed of 211 Tunisian patients with de novo AML and 14 healthy donors. The 11 last exons coding the set domain of EZH2 were investigated by PCR and Sanger sequencing. RESULTS: EZH2 mutations were identified in 66/211 (31%) patients with a sex ratio of 1.06. The presence of EZH2 mutations was statistically significantly associated with failure consolidation therapy (p = 0.004). There were no differences in the incidence of EZH2 mutations and FLT3-ITD, NPM1, DNMT3A and IDH2 mutations. When EZH2 mutations were associated with those of FLT3 or IDH2, a short duration of progression free survival was observed (p < 0.05). Moreover, CD7 aberrant markers conferred a poor prognosis in EZH2 mutated patients (p < 0.05). CONCLUSIONS: Given these data we conclude that EZH2 mutations are frequent in our patients, and can be used as a prognosis marker in combination with FLT3, IDH2 mutations and CD7 marker, to stratify AML patients and to guide therapeutic decisions.