Background. Allergic rhinitis (AR) is an inflammatory state categorized by a disturbance of immunoregulatory mechanisms. MicroRNA-155 (miRNA-155) has an essential role in regulating gene expression and can mediate the allergic TH2 process. Objective. In this study, we aimed to evaluate the role of miR-155 as a biomarker in AR and correlate its level with the total nasal symptom score (TNSS) and the levels of serum interleukin-4 (IL-4). Methods. This study included 90 children: 45 with pollen-induced AR and 45 healthy controls. Serum miR-155 expression levels were measured using quantitative real-time PCR. Human IL-4 ELIZA kits were used for the semiquantitative detection of the serum levels of IL-4. Receiver operating characteristic (ROC) curves were used to determine the best cutoff values for the studied parameters for the diagnosis of AR. Results. The demographic characteristics of the two groups were matched with respect to age and sex. The AR case group included 23 (51.1%) males and 22 (48.9%) females, while the control group included 24 (53.3%) males and 21 (46.7%) females. The miR-155 level was increased in the serum of children with pollen-induced AR compared with controls (mean difference = 2.8, p < 0.001 ). A significant positive correlation between the serum expression level of miR-155 and TNSS in children with AR was detected (r = 0.494, p < 0.001 ). However, no significant correlation was identified between the expression of miR-155 and that of IL-4. At a cutoff value of 1.09, the sensitivity of miR-155 as a biomarker for AR was 100%, and the specificity was 71.1%. Conclusion. MiR-155 expression levels were elevated in the serum of AR children. Therefore, miR-155 could be used as a biomarker in AR diagnosis.

Background. Chronic liver disease (CLD) is linked to immune system failure, which increases the risk of infections and consequences brought on by COVID-19. Therefore, we aimed to compare hospitalized COVID -19 patients with and without CLD to assess the effect of CLD on the severity of COVID-19 infection. Methods. The study was conducted between April and October 2022 at Zagazig university hospitals. It enrolled 108 subjects admitted at the isolation hospital for COVID-19 illness. The cases were allocated equally into three groups, group (I): Patients without evidence of liver disease.Group (II): patients with chronic hepatitis, and group (III): patients with cirrhotic liver.Result. There were significant correlations between the severity of COVID -19 and the CTP classification of Group III (r=0.5 p=0.05 in child A, r=0.08 p=0.05 in child B, r=0.4 p=0.001in child C). In addition, there were significant correlations between laboratory parameters such as INR (r=0.6, p=0.05), bilirubin (r=0.4, p=0.001), ALT (r= 0.5, p=0.05), and AST (r=0.08, p=0.05) and severity of COVID -19 in studies groups. Conclusion:Those with CLD and cirrhosis had a higher death rate. COVID-19 severity related to the Child-Turcotte-Pugh score (CTP) score.