Association of ACE1 I/D polymorphism and susceptibility to COVID-19 in Egyptian children and adolescents.

BACKGROUND: Given the sparse data on the renin-angiotensin system (RAS) and its biological effector molecules ACE1 and ACE2 in pediatric COVID-19 cases, we investigated whether the ACE1 insertion/deletion (I/D) polymorphism could be a genetic marker for susceptibility to COVID-19 in Egyptian children and adolescents. METHODS: This was a case-control study included four hundred sixty patients diagnosed with COVID-19, and 460 well-matched healthy control children and adolescents. The I/D polymorphism (rs1799752) in the ACE1 gene was genotyped by polymerase chain reaction (PCR), meanwhile the ACE serum concentrations were assessed by ELISA. RESULTS: The ACE1 D/D genotype and Deletion allele were significantly more represented in patients with COVID-19 compared to the control group (55% vs. 28%; OR = 2.4; [95% CI: 1.46-3.95]; for the DD genotype; P = 0.002) and (68% vs. 52.5%; OR: 1.93; [95% CI: 1.49-2.5] for the D allele; P = 0.032). The presence of ACE1 D/D genotype was an independent risk factor for severe COVID-19 among studied patients (adjusted OR: 2.6; [95% CI: 1.6-9.7]; P < 0.001. CONCLUSIONS: The ACE1 insertion/deletion polymorphism may confer susceptibility to SARS-CoV-2 infection in Egyptian children and adolescents. IMPACT: Recent studies suggested a crucial role of renin-angiotensin system and its biological effector molecules ACE1 and ACE2 in the pathogenesis and progression of COVID-19. To our knowledge, ours is the first study to investigate the association of ACE1 I/D polymorphism and susceptibility to COVID-19 in Caucasian children and adolescents. The presence of the ACE1 D/D genotype or ACE1 Deletion allele may confer susceptibility to SARS-CoV-2 infection and being associated with higher ACE serum levels; may constitute independent risk factors for severe COVID-19. The ACE1 I/D genotyping help design further clinical trials reconsidering RAS-pathway antagonists to achieve more efficient targeted therapies.

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.

Comparing different markers of tubular dysfunction in transfusion-dependent thalassemia patients.

BACKGROUND: Renal tubular dysfunction was reported in transfusion-dependent thalassemia (TDT) patients and ranges from mild to severe. The objectives of our study were identification of the best marker of early renal tubular dysfunction in TDT patients among the three most commonly used urinary biomarkers, named neutrophil gelatinase-associated lipocalin (NGAL), retinol-binding protein (RBP) and N-acetyl-D-glucosaminidase (NAG) and correlation of these biomarkers with different patient variables. METHODOLOGY: Sixty-one TDT patients and another 62 healthy children were enrolled in a cross-sectional study. Morning urine samples were taken for measurement of calcium, phosphorus, creatinine, microalbumin and markers of tubular dysfunction (NGAL, NAG and RBP). Urine NGAL/creatinine (UrNGAL/Cr), urine NAG/creatinine (UrNAG/Cr) and urine RBP/creatinine (UrRBP/Cr) ratios were used for accuracy. Patients were classified into 2 groups: group A, with tubular dysfunction and group b, without tubular dysfunction. RESULTS: Group A showed statistically significant higher UrNGAL/Cr (p < 0.001), UrRBP/Cr (p < 0.001) and UrNAG/Cr (p <0.001) than group B. In group A, microalbuminuria was detected only in 7 patients (28%) while it was detected in 12 patients (33.3%) in group B. By using ROC curve analysis, the diagnostic cutoff values for UrNGAL/Cr, UrRBP/Cr and UrNAG/Cr were 3713.38, 1614.85 and 56.56 ng/g, respectively. We found a statistically significant superiority of UrNGAL/Cr over UrRBP/Cr (p < 0.001) and UrRBP/Cr over UrNAG/Cr (p < 0.001). CONCLUSION: Evaluation of UrNGAL/Cr, UrRBP/Cr and UrNAG/Cr could early discriminate tubular dysfunction TDT patients from those with normal tubular function. UrNGAL/Cr is more accurate in early detection of tubular dysfunction when compared with the other two biomarkers.