Genome-Wide DNA Methylation Analysis of Chinese Patients with Systemic Lupus Erythematosus Identified Hypomethylation in Genes Related to the Type I Interferon Pathway.

BACKGROUND: Epigenetic variants have been shown in recent studies to be important contributors to the pathogenesis of systemic lupus erythematosus (SLE). Here, we report a 2-step study of discovery followed by replication to identify DNA methylation alterations associated with SLE in a Chinese population. Using a genome-wide DNA methylation microarray, the Illumina Infinium HumanMethylation450 BeadChip, we compared the methylation levels of CpG sites in DNA extracted from white blood cells from 12 female Chinese SLE patients and 10 healthy female controls. RESULTS: We identified 36 CpG sites with differential loss of DNA methylation and 8 CpG sites with differential gain of DNA methylation, representing 25 genes and 7 genes, respectively. Surprisingly, 42% of the hypomethylated CpG sites were located in CpG shores, which indicated the functional importance of the loss of DNA methylation. Microarray results were replicated in another cohort of 100 SLE patients and 100 healthy controls by performing bisulfite pyrosequencing of four hypomethylated genes, MX1, IFI44L, NLRC5 and PLSCR1. In addition, loss of DNA methylation in these genes was associated with an increase in mRNA expression. Gene ontology analysis revealed that the hypomethylated genes identified in the microarray study were overrepresented in the type I interferon pathway, which has long been implicated in the pathogenesis of SLE. CONCLUSION: Our epigenetic findings further support the importance of the type I interferon pathway in SLE pathogenesis. Moreover, we showed that the DNA methylation signatures of SLE can be defined in unfractionated white blood cells.

Roxadustat (FG-4592): Correction of Anemia in Incident Dialysis Patients.

Safety concerns with erythropoietin analogues and intravenous (IV) iron for treatment of anemia in CKD necessitate development of safer therapies. Roxadustat (FG-4592) is an orally bioavailable hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor that promotes coordinated erythropoiesis through HIF-mediated transcription. We performed an open-label, randomized hemoglobin (Hb) correction study in anemic (Hb≤10.0 g/dl) patients incident to hemodialysis (HD) or peritoneal dialysis (PD). Sixty patients received no iron, oral iron, or IV iron while treated with roxadustat for 12 weeks. Mean±SD baseline Hb was 8.3±1.0 g/dl in enrolled patients. Roxadustat at titrated doses increased mean Hb by ≥2.0 g/dl within 7 weeks regardless of baseline iron repletion status, C-reactive protein level, iron regimen, or dialysis modality. Mean±SEM maximal change in Hb from baseline (ΔHb(max)), the primary endpoint, was 3.1±0.2 g/dl over 12 weeks in efficacy-evaluable patients (n=55). In groups receiving oral or IV iron, ΔHb(max) was similar and larger than in the no-iron group. Hb response (increase in Hb of ≥1.0 g/dl from baseline) was achieved in 96% of efficacy-evaluable patients. Mean serum hepcidin decreased significantly 4 weeks into study: by 80% in HD patients receiving no iron (n=22), 52% in HD and PD patients receiving oral iron (n=21), and 41% in HD patients receiving IV iron (n=9). In summary, roxadustat was well tolerated and corrected anemia in incident HD and PD patients, regardless of baseline iron repletion status or C-reactive protein level and with oral or IV iron supplementation; it also reduced serum hepcidin levels.

Severe hypocalcaemia and hyperphosphataemia caused by oral sodium phosphate fleet solution in a haemodialysis patient after parathyroidectomy.

We report a case with severe electrolyte disturbance after the use of oral sodium phosphate solution (OSPS). A 69-year-old patient on haemodialysis received 45 mL of OSPS for bowel preparation. He had symptomatic hypocalcaemia with a serum calcium level of 0.95 mmol/L and serum phosphate level of 4.73 mmol/L. He was treated with haemodialysis and intravenous calcium supplementation. This patient had total parathyroidectomy recently leading to the absence of parathyroid hormone response. OSPS has been reported to cause life-threatening electrolyte disturbance especially in patients with renal failure. We suggest the use of safer alternatives for bowel preparations in renal failure patients.