BACKGROUND: Diabetic nephropathy (DN) is the most common cause of end-stage renal disease (ESRD) among type 2 diabetes mellitus patients (DM) in Malaysia. This study used microarray analysis to determine the gene expression profiling in ethnic Malay patients with type 2 DM.
METHODS: A total of 312 patients were recruited; 25 were on dialysis due to ESRD, 128 were classified as normoalbuminuric, 93 as microalbuminuric and 66 as macroalbuminuric, based on urine albumin to creatinine ratio of <3.5, between 3.5 and 35 and =35 mg/mmol, respectively.
RESULTS: Microalbuminuria was associated with up- and down-regulation of 2,694 and 2,538 genes, respectively, while macroalbuminuria was associated with up-regulation of 2,520 genes and down-regulation of 2,920 genes. There was significant up-regulation of 1,135 genes and down-regulation of 908 genes in the ESRD samples. Thirty-seven significantly up-regulated genes and 40 down-regulated genes were commonly expressed in all 3 groups of patients with worsening of renal functions. Up-regulated genes included major histocompatibility complex (HLA-C), complement component 3a receptor 1 (C3AR1), solute carrier family 16, member 3 (SLC16A3) and solute carrier family 9 (sodium/hydrogen exchanger) (SLC9A8). Consistently down-regulated genes included were bone morphogenetic phosphatase kinase (BMP2K), solute carrier family 12, member 1 (SLC12A1), solute carrier family 7 (SLC7A2), paternally expressed 10 (PEG10) and protein phosphatase 1 regulatory (inhibitor unit) (PPP1R1C).
CONCLUSION: This study has identified several genes of interest, such as HLA-C, SLC16A3, SLC9A8, SLC12A1 and SLC7A2, that require verification of their roles as susceptibility genes for diabetic nephropathy in ethnic Malays with type 2 DM.
Only unbiased estimates of end-stage renal disease (ESRD) incidence and trends are useful for disease control-identification of risk factors and measuring the effect of intervention.
♦ BACKGROUND: Peritonitis is one of the most common complications of peritoneal dialysis (PD). Understanding the risk factors of peritonitis in a multi-racial Asian population may help to improve outcomes on PD. ♦ METHODS: We conducted a prospective observational study to identify risk factors for PD-related peritonitis over a 1-year period in 15 adult PD centers. All peritonitis episodes were independently adjudicated. ♦ RESULTS: A total of 1,603 participants with a mean age of 51.6 years comprising 52.7% females, 62.6% ethnic Malays, 27.0% Chinese, and 8.1% Indians were recruited. The overall peritonitis rate was 1 episode per 44.0 patient-months with 354 episodes recorded in 282 (17.6%) patients over 15,588 patient-months. Significant risk factors of peritonitis were severe obesity (incidence-rate ratio [IRR] 3.32, 95% confidence interval [CI]: 1.30, 8.45), hypoalbuminemia (IRR 1.61, 95% CI: 1.06, 2.46), Staphylococcus aureus nasal carriage (IRR 2.26, 95% CI: 1.46, 3.50), and use of Fresenius system (Fresenius Medical Care North America, Waltham, MA, USA) (IRR 2.49, 95% CI: 1.27, 4.89). The risk of peritonitis was lower in those on automated PD compared with standard PD (IRR 0.43, 95% CI: 0.25, 0.74), and in centers with a patient-staff ratio of 15 to 29.9 (IRR 0.67, 95% CI: 0.49, 0.90) and ≥ 30 (IRR 0.52, 95% CI: 0.34, 0.80). Prevalent patients and exit-site care with topical antibiotics were also protective against peritonitis. Peritonitis rates varied between racial groups. The IRRs of overall peritonitis and gram-positive peritonitis in Chinese versus other racial groups were 0.65 (95% CI: 0.46, 0.90) and 0.47 (95% CI: 0.24, 0.91), respectively. ♦ CONCLUSIONS: Multiple patient, center, and PD-system factors influence the risk of peritonitis. In the Asian population, there are racial differences in the risk of peritonitis.