Incidence of Food allergy among patients with allergic conjunctivitis.

The prevalence of ocular allergy is increasing worldwide. Skin prick test is widely recognized as the most reliable method for diagnosing the incriminating allergen as regards type I hypersensitivity reactions. Food allergy results as immunological response to food protein which leads to occurrence of allergic conjunctivitis (AC), allergic rhinitis, asthma, atopic dermatitis, and eosinophilic esophagitis. There is a scarcity of research investigating the association between food allergy and AC. This retrospective cohort study aimed to determine the incidence of food allergy within AC patients and its linkage to disease intensity and to compare the response to sublingual immunotherapy after 4 months of therapy. The study included 240 individuals diagnosed with AC. Of these patients, only 214 (89.16%) cases exhibited positive skin prick test results and showed incidence of food allergy of 29.6 %. After 4 months of sublingual allergen immunotherapy, the total serum IgE level and the grades of severity decreased significantly (p 0.001 for each). On comparing patients with food allergy on sublingual immunotherapy and patients without food allergy and on sublingual immunotherapy, the change in total serum IgE concentration and the grade of severity did not differ among the two groups (p value was 0.63 and 1.00 respectively). In conclusion, food allergies can contribute to the development of AC. Sublingual allergen immunotherapy can be proposed as a promising therapeutic option for AC patients.

Prevalence of work-related asthma among Egyptian farmers in Great Cairo.

Work related asthma (WRA) refers to asthma induced by exposure to sensitizing agents and/or irritants in the workplace leaving health and economic consequences. Early diagnosis can improve the prognosis of WRA permitting sometimes full recovery. This study aimed to assess the prevalence of WRA among Egyptian adult agriculture workers. A multi-center cross sectional study included 150 adult workers from 4 different farms, during the period from 2019 and 2021. All participants were subjected to full medical history, clinical examination, chest x-ray, skin prick test and CBC to detect absolute eosinophilic count. Spirometry with post bronchodilatation test (reversibility test) at the farm (in the day of insecticide aerosol and without aerosol) and after a week off the farm was also done. Age, median ± SD, was 37.67 ± 9.75 years, duration of farming occupation was 21.84 ± 10.18 years. Of the 150 participants, 11 had WRA. Of these, 6 had allergic occupational asthma, 3/11 had work exacerbated asthma and only 2/11 had irritant occupational asthma. Of the allergic subjects, 7.3% tested positive to mixed pollens, 4.7% to Alternaria, 2% to penicillium and 2% to the farm pollens. The onset of respiratory symptoms was 13.45 ± 6.93 months after start working in the farm. A statistical significance was observed between WRA and non-WRA individuals regarding age, duration of farming occupation and asthma symptoms during workday (P < 0.001). There was a statistical significance between WRA group and non-WRA group regarding FEV1, FEV1/FVC ratio carried out at work, during holidays and during spraying (P < 0.001). Absolute eosinophilic count, mean among WRA group was 0.55 ± 0.13 (×103cells/mm3) with significance between WRA and non-WRA (P= 0.001). Farming occupation may cause WRA, therefore, more attention should be given to minimize exposure and risk of inducing WRA.

Toll-Like Receptor-4 Gene (Asp299Gly) polymorphism in allergic conjunctivitis.

Allergic conjunctivitis (AC) is an allergic reaction that causes inflammation of the conjunctiva. Toll-like receptors (TLRs) are essential innate immune receptors that contribute to developing various allergic diseases. This case-control study aims to determine the correlation between TLR-4 gene (Asp299Gly) polymorphism and AC incidence and severity. The study included 70 AC patients and 70 non-allergic controls. All included subjects were subjected to a skin prick test, total immunoglobulin E (IgE) measurement, and TLR-4 gene (Asp299Gly) polymorphism detection by PCR restriction fragment length polymorphism (PCR-RFLP) technique. AC patients had significantly higher total IgE levels than controls (P ≤ 0.001). The frequency of the wild-type AA and heterozygous AG genotype were significantly lower in AC patients compared to controls (60 % vs. 80 % and 8.6% vs. 12.9 %, respectively). In contrast, the homozygous mutant GG genotype was significantly more prevalent among AC patients than controls (31.4 % vs. 7.1 %). Furthermore, the wild AA genotype was strongly associated with mild disease (68.2%); nonetheless, the homozygous mutant GG genotype was linked to severe disease (53.8%). The heterozygous AG genotype was only found in moderate AC patients (17.1%). AC patients with the mutant G allele may be more likely to have a severe course of AC.

Mannose-binding lectin serum levels and (Gly54asp) gene polymorphism in recurrent aphthous stomatitis: A case-control study.

Objectives: Dysregulation of the immune response appears to play a significant role in recurrent aphthous stomatitis (RAS) development. The main objective of this case-control study is to investigate the blood levels of mannose-binding lectin (MBL) and the frequency of the MBL2 gene (gly54asp) polymorphism in RAS patients, including 40 RAS patients and 40 healthy controls. Methods: Serum MBL levels were determined by ELISA, while the PCR-restriction fragment length polymorphism was used in MBL2 genotyping. Results: The median serum MBL level was significantly lower in the RAS group than in the control group (975 ng/mL (545-1320) vs. 1760 ng/mL (1254-2134); p≤ 0.001). The MBL levels were significantly lower in the BB genotype, whereas they were significantly higher in the wild type AA with a median of 525 and 1340 ng/mL, respectively (p =0.005). The B allele was expressed in significantly higher percentages of RAS patients than in controls. There was no significant association between MBL serum levels (p=0.685) or MBL2 codon 54 genotypes (p=0.382) with the type of ulcers. Conclusion: There was an association between low MBL serum levels and the variant allele B of the MBL2 (gly54asp) gene, and the susceptibility to RAS. As a result, potential novel therapeutic options for RAS patients with MBL deficiency should be investigated.

Toll-Like Receptor 4 Polymorphisms (896A/G and 1196C/T) as an Indicator of COVID-19 Severity in a Convenience Sample of Egyptian Patients.

BACKGROUND: The clinical spectrum of COVID-19 is extremely variable. Thus, it is likely that the heterogeneity in the genetic make-up of the host may contribute to disease severity. Toll-like receptor (TLR)-4 plays a vital role in the innate immune response to SARS-CoV-2 infection. The susceptibility of humans to severe COVID-19 concerning TLR-4 single nucleotide polymorphisms (SNPs) has not been well examined. OBJECTIVE: The goal of this research was to investigate the association between TLR-4 (Asp299Gly and Thr399Ile) SNPs and COVID-19 severity and progression as well as the cytokine storm in Egyptian patients. METHODS: We genotyped 300 adult COVID-19 Egyptian patients for TLR-4 (Asp299Gly and Thr399Ile) SNPs using PCR-restriction fragment length polymorphism (PCR-RFLP). We also measured interleukin (IL)-6 levels by enzyme-linked immunosorbent assay (ELISA) as an indicator of the cytokine storm. RESULTS: The minor 299Gly (G) and 399Ile (T) alleles were associated with a significant (P < 0.001) positive risk of severe COVID-19 (OR = 3.14; 95% CI = 2.02-4.88 and OR = 2.75; 95% CI = 1.66-4.57), their frequency in the severe group were 71.8% (84/150) and 70.7% (58/150), respectively. We detected significant differences between TLR-4 (Asp299Gly, Thr399Ile) genotypes with regard to serum levels of IL-6. Levels of IL-6 increased significantly with the presence of the mutant 299Gly (G) and 399Ile (T) alleles to reach the highest levels in the Gly299Gly (GG) and the Ile399Ile (TT) genotypes (170 pg/mL (145-208.25) and 112 pg/mL (24-284.75), respectively). CONCLUSION: The TLR-4 (Asp299Gly and Thr399Ile) minor alleles 299Gly (G) and 399Ile (T) are associated with COVID-19 severity, mortality, and the cytokine storm.

Association between serum zonulin level and severity of house dust mite allergic asthma.

BACKGROUND: Increased intestinal permeability, either due to the exposure to antigens in asthmatic patients or due to a barrier defect, plays a critical role in susceptibility to environmental allergens. House dust mite allergy occurs more commonly than any other type of allergy among Egyptian asthmatic patients. AIM: To assess the relation between serum zonulin level as a marker of increased intestinal permeability and the severity of house dust mite allergic asthma. METHODS: A case-control study which included 48 patients with house dust mite allergic asthma and 48 healthy control subjects attending the Allergy and Immunology Unit, Microbiology and Immunology Department, Faculty of Medicine, Zagazig University. RESULTS: A statistically significant difference was detected between the two studied groups with respect to serum IgE and serum zonulin levels (p Ë‚ 0.001 and ˂ 0.001, respectively). The mean serum zonulin was equal to 258.3 ± 153.01 ng/ml in the asthmatic group and 80 ± 13 ng/ml in the control group. Serum zonulin level significantly increased with the increase of asthma severity (p ˂ 0.001). The cut off value of serum zonulin was ≥ 198 ng/ml, and the area under the curve was 0.76. It displayed sensitivity equal to 80% and specificity equal to 71.4%. Its negative predictive value was equal to 83.3%. CONCLUSION: Intestinal barrier dysfunction contributes to the pathogenesis of allergic asthma. Serum zonulin level reflects an increase in intestinal permeability. Zonulin acts as prognostic factor of severity in asthma. Correction of the gut barrier defect may have a potential positive prognostic effect in asthma.