Helicobacter pylori Oncogenicity: Mechanism, Prevention, and Risk Factors

Helicobacter pylori (H. pylori) is the most common cause of gastric ulcer; however, its association with gastric cancer has been proved through a variety of studies. Importantly, H. pylori infection affects around half of the world’s population leading to a variety of gastric problems and is mostly present in asymptomatic form. Although about 20% of people infected with H. pylori develop preneoplastic gastric lesions in later stages of their life, around 2% of infected individuals develop gastric cancer. Nevertheless, the outcome of H. pylori infection is determined by complex interaction between the host genetics, its environment, and virulence factors of infecting strain. There are several biomarkers/traits of H. pylori that have been linked with the onset of cancer. Among these, presence of certain major virulence factors including cytotoxin-associated gene A (CagA), vacuolating cytotoxin (VacA), and outer inflammatory protein A (OipA) plays a significant role in triggering gastric cancer. These factors of H. pylori make it a potent carcinogen. Therefore, eradication of H. pylori infection has shown positive effects on decreasing the risk of gastric cancer, but this has become a challenge due to the development of antibiotic resistance in H. pylori against the antibiotics of choice. Thus, the unmet need is to develop new and effective treatments for H. pylori infection, considering the antimicrobial resistance in different regions of the world. This review discusses the properties of H. pylori associated with increased risk of gastric cancer, antibiotic resistance pattern, and the possible role of eradication of H. pylori in preventing gastric cancer

Faecal carriage of CTX-M-15-producing klebsiella pneumoniae in patients with acute gastroenteritis

Background & objectives: Data on extended-spectrum beta-lactamases (ESBLs) produced by Gram-negative bacteria including Klebsiella pneumoniae especially molecular types of ESBL genes from India are limited. The present study was conducted to investigate the carriage and ESBL contents of multidrug-resistant K. pneumoniae recovered from patients with gastroenteritis in a rural village in southern India

Direct DNA Sequencing-Based Analysis of Microbiota Associated with Hematological Malignancies in the Eastern Province of Saudi Arabia

Introduction. Bloodstream infections (BSI) among patients with hematological malignancies (HM) could predispose them to higher morbidity and mortality for various underlying conditions. Several microorganisms, either pathogenic or opportunistic normal human flora, could cause severe bacteremia and septicemia. While conventional methods have their own limitations, molecular methods such as next-generation sequencing (NGS) can detect these blood infections with more reliability, specificity, and sensitivity, in addition to information on microbial population landscape. Methodology. Blood samples from HM patients (n=50) and volunteer blood donor control individuals with no HM (n=50) were subjected to 16S rRNA gene amplification using standard PCR protocols. A metagenomic library was prepared, and NGS was run on a MiSeq (Illumina) sequencer. Sequence reads were analyzed using MiSeq Reporter, and microbial taxa were aligned using the Green Genes library. Results. 82% of the patients showed BSI with Gram-negative bacteria as the most predominant group. E. coli comprised a major chunk of the bacterial population (19.51%), followed by K. pneumoniae (17.07%). The CoNS and Viridans Streptococci groups are 17.07% and 14.63%, respectively. Other major species were S. aureus (9.75%), P. aeruginosa (7.31%), A. baumannii (4.87%), E. cloacae (4.87%), and P. mirabilis (4.87%). 34.14% of the cases among patients showed a Gram-positive infection, while 14.63% showed polymicrobial infections. Conclusion. Most of the BSI in patients were characterized by polymicrobial infections, unlike the control samples. Molecular methods like NGS showed robust, fast, and specific identification of infectious agents in BSI in HM, indicating the possibility of its application in routine follow-up of such patients for infections

Viral dynamics and real-time rt-pcr ct values correlation with disease severity in covid-19

Real-time RT-PCR is considered the gold standard confirmatory test for coronavirus disease 2019 (COVID-19). However, many scientists disagree, and it is essential to understand that several factors and variables can cause a false-negative test. In this context, cycle threshold (Ct) values are being utilized to diagnose or predict SARS-CoV-2 infection. This practice has a significant clinical utility as Ct values can be correlated with the viral load. In addition, Ct values have a strong correlation with multiple haematological and biochemical markers. However, it is essential to consider that Ct values might be affected by pre-analytic, analytic, and post-analytical variables such as collection technique, specimen type, sampling time, viral kinetics, transport and storage conditions, nucleic acid extraction, viral RNA load, primer designing, real-time PCR efficiency, and Ct value determination method. Therefore, understanding the interpretation of Ct values and other influential factors could play a crucial role in interpreting viral load and disease severity. In several clinical studies consisting of small or large sample sizes, several discrepancies exist regarding a significant positive correlation between the Ct value and disease severity in COVID-19. In this context, a revised review of the literature has been conducted to fill the knowledge gaps regarding the correlations between Ct values and severity/fatality rates of patients with COVID-19. Various databases such as PubMed, Science Direct, Medline, Scopus, and Google Scholar were searched up to April 2021 by using keywords including “RT-PCR or viral load”, “SARS-CoV-2 and RT-PCR”, “Ct value and viral load”, “Ct value or COVID-19”. Research articles were extracted and selected independently by the authors and included in the present review based on their relevance to the study. The current narrative review explores the correlation of Ct values with mortality, disease progression, severity, and infectivity. We also discuss the factors that can affect these values, such as collection technique, type of swab, sampling method, etc