Angiotensin-converting enzyme insertion/deletion gene polymorphism in Egyptian children with systemic lupus erythematosus: a possible relation to proliferative nephritis

Introduction Angiotensin-converting enzyme (ACE) is crucial in the pathogenesis of systemic lupus erythematosus through angiotensin II which regulates vascular tone and endothelial functions. Objectives To study the frequency of ACE insertion/deletion (I/D) gene polymorphism in Egyptian children with systemic lupus erythematosus and its possible relation to the renal pathology in cases with lupus nephritis. Subjects and methods The frequency of ACE gene insertion/deletion polymorphism genotypes was determined in 78 Egyptian children with systemic lupus erythematosus and compared to a matched group of 140 healthy controls using polymerase chain reaction. Results The DD genotype of the ACE gene was higher in systemic lupus erythematosus patients when compared to controls ( P<0.0001; odds ratio (OR) 2.4; 95% confidence interval (CI) 1.7-3.3) and the D allele was more frequent than the I allele in systemic lupus erythematosus patients in comparison to controls ( P < 0.0001; OR = 2.2; 95% CI = (1.6-3.1). In the lupus nephritis group, the DD genotype was significantly higher in those with proliferative lupus nephritis when compared to those with non-proliferative lupus nephritis ( P = 0.02; OR = 1.45; 95% CI = 1.4-1.6). Also, patients with proliferative lupus nephritis showed a higher frequency of the D allele ( P < 0.001; OR = 1.98; 95% CI = 1.3-2.9). Conclusion The D allele and DD genotype of the ACE gene appear to be a risk factor for the susceptibility of systemic lupus erythematosus and occurrence of proliferative nephritis in Egyptian children.

Serum 25-OH vitamin D level in treatment-naïve systemic lupus erythematosus patients: Relation to disease activity, IL-23 and IL-17

Objectives The aim of this study was to assess the vitamin D status in treatment-naïve SLE patients and its association with clinical and laboratory markers of disease activity, including serum levels of IL-17 and IL-23. Methods Fifty-seven treatment-naïve SLE patients along with 42 matched controls were included. SLEDAI score was used to estimate disease activity. Serum levels of 25(OH) D, IL-17 and IL-23 were measured. Results The median level of 25(OH) D in SLE patients (40.8; 4-70 ng/ml) was significantly lower than in the controls (47; 25-93 ng/ml) ( P = 0.001). A total of 38.6% of SLE cases had 25 (OH) D levels < 30 ng/ml (hypovitaminosis D) vs. 4.8% of the controls ( P < 0.0001). Apart from thrombocytopenia, vitamin D was not associated with clinical signs of SLE. There were negative correlations between serum 25(OH) D and serum levels of IL-17, IL-23 and ANA (rho = -0.5, -0.8, -0.5, P ≤ 0.05) in SLE patients. Conclusion Hypovitaminosis D is prevalent in treatment naïve SLE patients. It contributes to ANA antibody production and is associated with high serum levels of IL-23 and IL-17; thus they may trigger the inflammatory process in SLE.