Genetic Basis of Delayed Hypersensitivity Reactions to Drugs in Jewish and Arab Populations

Ethnic Differences in Clinical Presentations and Esophageal High-Resolution Manometry Findings in Patients with Achalasia

BACKGROUND

Ethnic differences in achalasia presentations have scarcely been described. The association between achalasia and immunologic HLA haplotypes suggests that there may be a genetic predisposition. We aimed to evaluate differences in demographic, clinical, endoscopic, and manometric findings between two distinct ethnic groups with achalasia-Israeli Arabs (IA) and Israeli Jews (IJ).

METHODS

A retrospective study was performed at two medical centers. High-resolution manometry (HRM) reports were reviewed for newly-diagnosed achalasia patients. Demographic data, clinical presentations, endoscopy reports, and HRM metrics including the integrated relaxation pressure (IRP) were all reviewed.

RESULTS

Overall, 94 achalasia patients were included (53.2% male; mean age 54.5 ± 18.0). 43 patients were IA (45.7%). Body mass index (BMI) was similar in both groups. Compared to IJ, the IA patients had more esophageal dysphagia (100% vs. 88.2%; P = 0.022), chest pain (46.5% vs. 25.5%; P = 0.033), and a tortuous esophagus on endoscopy (23.3% vs. 3.9%; p = 0.005). IA patients were also diagnosed at a younger age than IJ patients (50.9 ± 17.5 vs. 57.5 ± 18.0; p = 0.039). Furthermore, IRP values were higher among IA patients than IJ patients (32.2 ± 13.8 vs. 23.3 ± 8.4; p < 0.001). A regression model analysis found that ethnicity significantly predicted IRP (β = - 10, p < .001).

CONCLUSION

Ethnicity appears to affect achalasia clinical presentation and HRM findings. IA achalasia patients are diagnosed at a younger age, present with more severe esophageal symptoms, and have a higher IRP compared to IJ patients. Additional studies of diverse, multiethnic populations, especially with genetic evaluations, are required to further assess the role of ethnicity in achalasia.

Genophenotypic Factors and Pharmacogenomics in Adverse Drug Reactions

Adverse drug reactions (ADRs) rank as one of the top 10 leading causes of death and illness in developed countries. ADRs show differential features depending upon genotype, age, sex, race, pathology, drug category, route of administration, and drug–drug interactions. Pharmacogenomics (PGx) provides the physician effective clues for optimizing drug efficacy and safety in major problems of health such as cardiovascular disease and associated disorders, cancer and brain disorders. Important aspects to be considered are also the impact of immunopharmacogenomics in cutaneous ADRs as well as the influence of genomic factors associated with COVID-19 and vaccination strategies. Major limitations for the routine use of PGx procedures for ADRs prevention are the lack of education and training in physicians and pharmacists, poor characterization of drug-related PGx, unspecific biomarkers of drug efficacy and toxicity, cost-effectiveness, administrative problems in health organizations, and insufficient regulation for the generalized use of PGx in the clinical setting. The implementation of PGx requires: (i) education of physicians and all other parties involved in the use and benefits of PGx; (ii) prospective studies to demonstrate the benefits of PGx genotyping; (iii) standardization of PGx procedures and development of clinical guidelines; (iv) NGS and microarrays to cover genes with high PGx potential; and (v) new regulations for PGx-related drug development and PGx drug labelling.

Association of KDR rs1870377 genotype with clopidogrel resistance in patients with post percutaneous coronary intervention

Background

Clopidogrel is an antiplatelet therapy that is widely used in pre and post percutaneous (PCI) coronary intervention procedures to prevent platelet aggregation and stent restenosis. However, there is a wide inter-individual variation in clopidogrel response and some patients showed resistance against the activity of Clopidogrel. Kinase insert domain receptor (KDR) gene is responsible for the transcription of vascular endothelial growth factor receptor 2 (VEGFR2) that plays a major role in the cardiovascular diseases (CVDs) and platelet aggregation. The aim of this study was to find out the association of KDR rs1870377 genotype with clopidogrel resistance (CR) in CVD patients, of Iraqi Arabic origin, hospitalized for elective PCI.

Materials and methods

This study was a case-control study with a total of 324 PCI patients. Those patients were classified into 213 patients with non-clopidogrel resistant and 111 patients with CR, depending on the analysis of platelet activity phenotype after clopidogrel administration. KDR rs1870377 was genotyped for all patients using polymerase chain reaction-restriction fragment length polymorphism technique and confirmed by DNA Sänger sequencing through applying Biosystems Model (ABI3730x1).

Results

KDR rs1870377 SNP is strongly associated (Chi-sqaure, p vale <0.05) with CR under dominant, co-dominant and recessive models. Additionally, A allele in the rs1870377 SNP may have an impact on the serum levels of VEGFR2 and low density lipoprotein.

Conclusions

KDR rs1870377 SNP is a potential genetic biomarker of CR among CVD patients of Iraqi Arabic origin. Further clinical studies, with larger sample, are required to confirm the findings of this study.