Polymorphisms in the IL-6 and IL-6R receptor genes as new diagnostic biomarkers of acute appendicitis: a study on two candidate genes in pediatric patients with acute appendicitis

Comparison of miRNA profiles in the immune response of pediatric acute appendicitis and pediatric enterobiasis patients caused by Enterobius vermicularis

BACKGROUND

The aim of this study was to determine and compare the miRNA profile in the immune response with the parasite in pediatric patients with acute appendicitis caused by Enterobius vermicularis and in pediatric patients with enterobiasis.

METHODS

A total of 30 tissue samples, which were operated with the diagnosis of pediatric acute appendicitis in the last 10 y and Enterobius vermicularis was detected by histopathological findings, were analyzed. In addition, blood samples were taken from 30 pediatric patients diagnosed with enterobiasis for this study. The miRNAs that activate T and B cells were evaluated by a quantitative real-time PCR, statistically calculated within ΔΔCt values, and fold changes were evaluated by Welch's T test, in which p<0.5 was considered to be significant.

RESULTS

It was found that 48 out of 136 (35.3%) miRNAs differed between the pediatric patient and healthy control groups. It was determined that 22 (57.9%) of the different miRNAs were T cell activating miRNAs and 26 (68.4%) were B cell activating miRNAs. While there was a significant difference in miRNA values activating T cells in two patient groups (p<0.01), there was no significant difference in miRNA values activating B cells (p>0.01).

CONCLUSIONS

In the study, although Enterobius vermicularis was the causative agent in both patient groups, it was revealed that the immune response of patients with acute appendicitis was more affected than enterobiasis patients.

Whole Genome Sequencing Highlights the Pathogenic Profile in Nocardia Keratitis

Purpose

Nocardia keratitis is a serious and sight-threatening condition. This study aims to reveal the virulence and antimicrobial resistance gene profile of Nocardia strains using whole genome sequencing.

Methods

Whole-genome sequencing was performed on 23 cornea-derived Nocardia strains. Together with genomic data from the respiratory tract and the environment, 141 genomes were then utilized for phylogenetic and pan-genome analyses, followed by virulence and antibiotic resistance analysis. The correlations between virulence genes and pathogenicity were experimentally validated, including the characteristics of Nocardia colonies and clinical and histopathological evaluations of Nocardia keratitis mice models.

Results

Whole-genome sequencing of 141 Nocardia strains revealed a mean of 220 virulence genes contributed to bacterial pathogenesis. The mce gene family analysis led to the categorization of strains from the cornea into groups A, B, and C. The colonies of group C had the largest diameter, height, and fastest growth rate. The size of corneal ulcers and the clinical scores showed a significant increase in mouse models induced by group C. The relative expression levels of pro-inflammatory cytokines (CD4, IFN-γ, IL-6Rα, and TNF-α) in the lesion area exhibited an increasing trend from group A to group C. Antibiotic resistance genes (ARGs) spanned nine distinct drug classes, four resistance mechanisms, and seven primary antimicrobial resistance gene families.

Conclusions

Whole genome sequencing highlights the pathogenic role of mce gene family in Nocardia keratitis. Its distribution pattern may contribute to the distinct characteristics of the growth of Nocardia colonies and the clinical severity of the mice models.

Impact of Human Genetic Variation on C-Reactive Protein Concentrations and Acute Appendicitis

Background

Acute appendicitis is one of the most common abdominal emergencies worldwide. Both environmental and genetic factors contribute to the disease. C-reactive protein (CRP) is an important biomarker in the diagnosis of acute appendicitis. CRP concentrations are significantly affected by genetic variation. However, whether such genetic variation is causally related to appendicitis risk remains unclear. In this study, the causal relationship between single-nucleotide polymorphisms (SNPs) associated with circulating CRP concentrations and the risk and severity of acute appendicitis was investigated.

Methods

CRP concentrations in serum of appendicitis patients (n = 325) were measured. Appendicitis was categorized as complicated/uncomplicated and gangrenous/non-gangrenous. Imputed SNP data (n = 287) were generated. A genome-wide association study (GWAS) on CRP concentrations and appendicitis severity was performed. Intersection and colocalization of the GWAS results were performed with appendicitis and CRP-associated loci from the Pan-UKBB cohort. A functional-genomics approach to prioritize genes was employed.

Results

Thirteen percent of significant CRP quantitative trait loci (QTLs) that were previously identified in a large cohort of healthy individuals were replicated in our small patient cohort. Significant enrichment of CRP-QTLs in association with appendicitis was observed. Among these shared loci, the two top loci at chromosomes 1q41 and 8p23.1 were characterized. The top SNP at chromosome 1q41 is located within the promoter of H2.0 Like Homeobox (HLX) gene, which is involved in blood cell differentiation, and liver and gut organogeneses. The expression of HLX is increased in the appendix of appendicitis patients compared to controls. The locus at 8p23.1 contains multiple genes, including cathepsin B (CTSB), which is overexpressed in appendix tissue from appendicitis patients. The risk allele of the top SNP in this locus also increases CTSB expression in the sigmoid colon of healthy individuals. CTSB is involved in collagen degradation, MHC class II antigen presentation, and neutrophil degranulation.

Conclusions

The results of this study prioritize HLX and CTSB as potential causal genes for appendicitis and suggest a shared genetic mechanism between appendicitis and CRP concentrations.

Novel molecular biomarkers and diagnosis of acute appendicitis in children

Reliable and efficient diagnosis of pediatric appendicitis is essential for the establishment of a clinical management plan and improvement of patient outcomes. Current strategies used to diagnose a child presenting with a suspected appendicitis include laboratory studies, clinical scores and diagnostic imaging. Although these modalities work in conjunction with each other, one optimal diagnostic strategy has yet to be agreed upon. The recent introduction of precision medicine techniques such as genomics, transcriptomics, proteomics and metabolomics has increased both the diagnostic sensitivity and specificity of appendicitis. Using these novel strategies, the integration of precision medicine into clinical practice via point-of-care technologies is a plausible future. These technologies would assist in the screening, diagnosis and prognosis of pediatric appendicitis.

Correlation between interleukin gene polymorphisms and current prevalence and mortality rates due to novel coronavirus disease 2019 (COVID-2019) in 23 countries

Background

The novel coronavirus disease 2019 (COVID‐19) infection may rely on a potential genetic background for the variations in the inflammatory response. We aimed to investigate the possible correlation between polymorphisms in the IL‐6 gene at rs1800796/rs1800795, in IL‐6R at rs2228145, in IL‐10 at rs1800896 and rs1800871, in IL‐17 at rs2275913 and rs763780 loci, and COVID‐19 prevalence and mortality rates among populations of 23 countries.

Methods

We searched the literature for polymorphisms in China, Japan, India, Spain, Mexico, Sweden, Turkey, Brazil, Russia, Poland, Italy, South Africa, Netherlands, Greece, Germany, UK, Iran, Finland, Czechia, Tunisia, Norway, Egypt, Croatia. We recorded the prevalence and mortality rates (per million) caused by the Coronavirus infection recorded on 7th September 2020 and 6th December 2020.

Results

There was a significant positive correlation between the frequency of AG genotype of rs1800896 and prevalence recorded on 6th December 2020 (r: 0.53, r²: 0.28, p < .05). There was a significant negative correlation between the mortality rates recorded on 7th September, and the AG genotype of rs2275913 (r: −0.51, r²: 0.26, p < .05). There was a significant positive correlation between the prevalence recorded on 6th December, and TT genotype at rs763780 (r: 0.65, r²:0.42, p < .05) while a negative correlation between prevalence and TC genotype at rs763780 (r: −0.66, r²: 0.43, p < .05). Also, a significant negative correlation was found between mortality rates recorded on 6th December 2020 and CC genotype at rs763780 (r: −0.56, r²: 0.31, p < .05).

Conclusion

The variations in prevalence of COVID‐19 and its mortality rates among countries may be explained by the polymorphisms at rs1800896 in IL‐10, rs2275913 in IL‐17A, and rs763780 loci in the IL‐17F gene.

The variations in prevalence of COVID‐19 and its mortality rates among 23 countries may be explained by the polymorphisms at rs1800896 in IL‐10, rs2275913 in IL‐17A, and rs763780 loci in the IL‐17F gene.

AG genotype frequency of rs1800896 was positively correlated with prevalence recorded on 6th December 2020.

The mortality rates recorded on 7th September was negatively correlated with AG genotype frequency of rs2275913.

The prevalence recorded on 6th December was positively correlated with frequency of TT and negatively with TC genotype at rs763780.

The mortality rates recorded on 6th December 2020 was negatively correlated with CC genotype frequency at rs763780.

Genetic polymorphism patterns suggest a genetic driven inflammatory response as pathogenesis in appendicitis

PURPOSE

The pathogenesis of appendicitis is not well understood. Environmental factors are regarded most important, but epidemiologic findings suggest a role of inflammatory and genetic mechanisms. This study determines the association of single nucleotide polymorphisms (SNPs) of inflammatory genes with appendicitis.

METHODS

As part of a larger prospective study on the diagnostic value of inflammatory variables in appendicitis, the genotype frequency of 28 polymorphisms in 26 inflammatory response genes from the appendicitis and control patients was analyzed in blood samples from 343 patients, 100 with appendicitis, and 243 with non-specific abdominal pain, using TaqMan SNP genotyping assays.

RESULTS

Associations with appendicitis were found for SNPs IL-13 rs1800925 with odds ratio (OR) 6.02 (95% CI 1.52-23.78) for T/T versus C/C + T/T, for IL-17 rs2275913 with OR 2.38 (CI 1.24-4.57) for A/A vs G/G + GA, for CCL22 rs223888 with OR 0.12 (0.02-0.90), and for A/A vs G/G + GA. Signs of effect modification of age for the association with appendicitis were found for IL-13 rs1800925 and CTLA4 rs3087243. Stratified analysis showed difference in association with severity of disease for IL-17 rs2275913 and CD44 rs187115.

CONCLUSIONS

The association of gene variants on risk of appendicitis and its severity suggest an etiologic role of genetically regulated inflammatory response. This may have implications for understanding the prognosis of untreated appendicitis as a possible self-limiting disorder and for understanding the inverse association of appendicitis with ulcerative colitis.