Vitamin D deficiency and vitamin D receptor FokI polymorphism as risk factors for COVID-19.

BACKGROUND: Given the sparse data on vitamin D status in pediatric COVID-19, we investigated whether vitamin D deficiency could be a risk factor for susceptibility to COVID-19 in Egyptian children and adolescents. We also investigated whether vitamin D receptor (VDR) FokI polymorphism could be a genetic marker for COVID-19 susceptibility. METHODS: One hundred and eighty patients diagnosed to have COVID-19 and 200 matched control children and adolescents were recruited. Patients were laboratory confirmed as SARS-CoV-2 positive by real-time RT-PCR. All participants were genotyped for VDR Fok1 polymorphism by RT-PCR. Vitamin D status was defined as sufficient for serum 25(OH) D at least 30 ng/mL, insufficient at 21-29 ng/mL, deficient at <20 ng/mL. RESULTS: Ninety-four patients (52%) had low vitamin D levels with 74 (41%) being deficient and 20 (11%) had vitamin D insufficiency. Vitamin D deficiency was associated with 2.6-fold increased risk for COVID-19 (OR = 2.6; [95% CI 1.96-4.9]; P = 0.002. The FokI FF genotype was significantly more represented in patients compared to control group (OR = 4.05; [95% CI: 1.95-8.55]; P < 0.001). CONCLUSIONS: Vitamin D deficiency and VDR Fok I polymorphism may constitute independent risk factors for susceptibility to COVID-19 in Egyptian children and adolescents. IMPACT: Vitamin D deficiency could be a modifiable risk factor for COVID-19 in children and adolescents because of its immune-modulatory action. To our knowledge, ours is the first such study to investigate the VDR Fok I polymorphism in Caucasian children and adolescents with COVID-19. Vitamin D deficiency and the VDR Fok I polymorphism may constitute independent risk factors for susceptibility to COVID-19 in Egyptian children and adolescents. Clinical trials should be urgently conducted to test for causality and to evaluate the efficacy of vitamin D supplementation for prophylaxis and treatment of COVID-19 taking into account the VDR polymorphisms.

Cytokine profile in Egyptian children and adolescents with COVID-19 pneumonia: A multicenter study.

BACKGROUND: To date, the cytokine profile in children and adolescent with novel coronavirus disease 2019 (COVID-19) has not been reported. OBJECTIVES: We investigated serum levels of a panel of key cytokines in children and adolescent with COVID-19 pneumonia with a primary focus on "cytokine storm" cytokines such as interleukin (IL)-1ß, IL-6, IL-17, IL-2, IL-4, IL-10, interferon (IFN-γ), tumor necrosis factor (TNF)-α, and two chemokines interferon-inducible protein-10 (IP-10) and IL-8. We also studied whether these cytokines could be potential markers for illness severity in COVID-19 pneumonia. METHODS: Ninety-two symptomatic patients aged less than 18 years with confirmed COVID-19 pneumonia and 100 well-matched healthy controls were included in this multi-center study. For all patients, the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in respiratory fluid specimens was detected by real-time reverse-transcriptase polymerase chain reaction. We measured serum concentrations of studied cytokines by using flow cytometry. RESULTS: Patients with COVID-19 had significantly higher median IL-1ß, IL-6, IL-8, IL-10, IL-17, TNF-α, and IP-10 serum levels than did control children (all p < 0.01). Patients with severe COVID-19 pneumonia had significantly higher median IL-1ß, IL-6, and IP-10 serum levels as compared with those with moderate COVID-19 pneumonia; all p < 0.01. ROC analysis revealed that three of the studied markers (IL-6, IL-1ß, and IP-10) could predict severe COVID-19 pneumonia cases with the largest AUC for IL-6 of 0.893 (95% confidence interval: 0.84-0.98; p < 0.01). CONCLUSION: Our study shows that pediatric patients with COVID-19 pneumonia have markedly elevated serum IL-1ß, IL-6, IL-8, IL-10, IL-17, TNF-α, and IP-10 levels at the initial phase of the illness indicating a cytokine storm following SARS-CoV-2 infection. Moreover, serum IL-6, IL-1ß, and IP-10 concentrations were independent predictors for severe COVID-19 pneumonia.

The impact of Fc gamma receptor IIa and IIIa gene polymorphisms on the therapeutic response of rituximab in Egyptian adult immune thrombocytopenic purpura.

Background In chronic immune thrombocytopenic purpura (ITP), rituximab removes the harmful autoantibodies through antibody-dependent cellular cytotoxicity. The response to rituximab in ITP is variable; the effectiveness of rituximab is influenced by the process of activation of effector fragment C gamma receptors (FcγRs). Genetic factors may affect the response to rituximab. Objectives The influence of FcγRIIa (H131R) and FcγRIIIa (V158F) gene polymorphisms on the response to rituximab in ITP. Methods One hundred ITP patients were genotyped for FcγRIIa (H131R) and FcγRIIIa (V158F) gene polymorphisms using the polymerase chain reaction-restriction fragment length polymorphism assay. The response at the end of the third month was assessed by direct platelets count. Polymorphisms were analyzed in relation to the response. Results The mean platelets count at end of weeks 1-4 of rituximab was statistically significantly higher in patients who achieved complete response (CR) than partial response or no response (P-value = .001). Although RR (44.4%) and HR (38.9%) genotypes were observed to be higher in patients who achieved CR compared with the wild (HH) genotype (16.7%), it was not statistically significantly different (P-value = .648). Conclusion The higher platelet count achieved early is predictive for a better response to rituximab later. FCγRIIA polymorphisms did not significantly influence response to rituximab in ITP.

Endothelial nitric oxide synthase gene polymorphisms and the risk of vasculopathy in sickle cell disease.

BACKGROUND: Sickle cell disease (SCD) is one of the major health problems in many parts of the world. SCD is characterized by multisystem complications with marked variability in its severity between patients, probably linked to nitric oxide (NO). Endothelial nitric oxide synthase (eNOS) enzyme which is responsible for NO synthesis may be implicated in SCD pathophysiology. AIM OF THE STUDY: To explore the possible association between the eNOS gene polymorphisms and severity of SCD. Furthermore, we examined the genomic diversity of these polymorphisms in SCD patients. METHODS: We genotyped 100 SCD patients and 80 controls were genotyped for eNOS 4a/b and eNOS 786T>C polymorphisms, using allele-specific polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism assay, respectively. Polymorphisms were analyzed in relation to severity of SCD manifestations. RESULTS: The homozygous mutant eNOS-786T>T genotype was significantly associated with high risk of acute chest syndrome (ACS). The wild-type eNOS-4a/4b genotype was protective against vaso-occlusive crisis (VOC) and pulmonary hypertension (PHTN). The mutant homozygous haplotype (C -4a) was significantly associated with the risk of ACS, VOC, and PHTN. CONCLUSION: eNOS intron 4 and eNOS T>C gene polymorphisms may be used as a genetic marker of prognostic value in SCD, as they are associated with unfavorable clinical outcomes.

Relation between glutathione S-transferase genes (GSTM1, GSTT1, and GSTP1) polymorphisms and clinical manifestations of sickle cell disease in Egyptian patients.

OBJECTIVES: Clinical manifestations of sickle cell disease (SCD) result from sickling of Hb S due to oxidation, which is augmented by accumulation of oxygen-free radicals. Deficiencies in normal antioxidant protective mechanism might lead to clinical manifestations of SCD like vaso-occlusive crisis (VOC) and acute chest syndrome (ACS). The glutathione system plays an important role in the removal of endogenous products of peroxidation of lipids, thus protecting cells and tissue against damage from oxidative stress. Impairment of the glutathione system due to genetic polymorphisms of glutathione S-transferase (GST) genes is expected to increase the severity of SCD manifestations. This report describes a case control study aimed at studying the ethnic-dependent variation in the frequency of GST gene polymorphisms among participants selected from the Egyptian population and to find out the association between GST gene polymorphisms and the severity of SCD manifestations. METHODS: We measured the frequency distribution of the three GSTs gene polymorphisms in 100 Egyptian adult SCD patients and 80 corresponding controls. GSTM1 and GSTT1 genotypes were determined by multiplex polymerase chain reaction (PCR). GSTP1 genotyping was conducted with a PCR-restriction fragment length polymorphism assay. RESULTS: The GSTM1 null genotype was significantly associated with ACS and VOC (P = 0.03 and 0.01, respectively). The GSTT1 null genotype was associated with significantly increased requirement of blood transfusion (P = 0.01). Absence of both GSTM1 and GSTT1 genes was significantly associated with pulmonary hypertension (P = 0.04). The non-wild-type GSTP1 polymorphism was not associated with clinical manifestations of SCD. DISCUSSION: Some GST gene polymorphisms were significantly associated with the worsening of the clinical manifestations of SCD.