Interventional nephrology and vascular access practice: A perspective from South and Southeast Asia.

South and Southeast Asia is the most populated, heterogeneous part of the world. The Association of Vascular Access and InTerventionAl Renal physicians (AVATAR Foundation), India, gathered trends on epidemiology and Interventional Nephrology (IN) for this region. The countries were divided as upper-middle- and higher-income countries as Group-1 and lower and lower-middle-income countries as Group-2. Forty-three percent and 70% patients in the Group 1 and 2 countries had unplanned hemodialysis (HD) initiation. Among the incident HD patients, the dominant Vascular Access (VA) was non-tunneled central catheter (non-TCC) in 70% of Group 2 and tunneled central catheter (TCC) in 32.5% in Group 1 countries. Arterio-Venous Fistula (AVF) in the incident HD patients was observed in 24.5% and 35% of patients in Group-2 and Group-1, respectively. Eight percent and 68.7% of the prevalent HD patients in Group-2 and Group-1 received HD through an AVF respectively. Nephrologists performing any IN procedure were 90% and 60% in Group-2 and Group 1, respectively. The common procedures performed by nephrologists include renal biopsy (93.3%), peritoneal dialysis (PD) catheter insertion (80%), TCC (66.7%) and non-TCC (100%). Constraints for IN include lack of time (73.3%), lack of back-up (40%), lack of training (73.3%), economic issues (33.3%), medico-legal problems (46.6%), no incentive (20%), other interests (46.6%) and institution not supportive (26%). Routine VA surveillance is performed in 12.5% and 83.3% of Group-2 and Group-1, respectively. To conclude, non-TCC and TCC are the most common vascular access in incident HD patients in Group-2 and Group-1, respectively. Lack of training, back-up support and economic constraints were main constraints for IN growth in Group-2 countries.

A single arm, prospective, open label, multicentre study for evaluation of efficacy and safety of IV CERA for treatment of chronic renal anaemia in dialysis patients not currently treated with ESA.

INTRODUCTION: CERA, a continuous erythropoietin receptor activator, has reported effective correction of anaemia in international clinical trials. OBJECTIVE: Objective of this study was to evaluate efficacy and safety of CERA in Indian patients who were on dialysis and has not received erythropoiesis stimulating agent (ESA) therapy in last 8 weeks. METHODS: In this open label, single arm, prospective, multi-centre study, 189 patients on dialysis, having Haemoglobin (Hb) between 8 - 10 g/dL and not receiving any ESA for last 8 weeks were included at 14 centers across India. CERA was given intravenous (IV) at the dose of 0.6 microg/kg every two weeks. Primary end point of the study was mean change in Hb concentration from baseline to end of the treatment period (TP) of 16 weeks. RESULTS: Mean change of Hb from baseline to end of TP was 2.11 +/- 1.37 g/dL and 2.08 +/- 1.29 g/dL in intent to treat (ITT) and per protocol (PP) population respectively. Mean time to achieve Hb response was 6.10 +/- 3.87 weeks and 6.16 +/- 3.92 weeks in ITT and PP populations respectively. Out of 68 adverse events (AEs) seen during study period, 33 were serious adverse events (SAEs). As per investigators all SAEs were related to underlying disease and not to the study medication. CONCLUSION: It is concluded that CERA administered once in two weeks in dialysis patients effectively corrected chronic kidney disease (CKD) related anaemia and was well tolerated with no significant untoward effect directly related to drug therapy in Indian population.

Serum catalytic Iron: A novel biomarker for coronary artery disease in patients on maintenance hemodialysis.

Cardiovascular disease is the leading cause of morbidity and mortality in maintenance hemodialysis (MHD) patients. We evaluated the role of serum catalytic iron (SCI) as a biomarker for coronary artery disease (CAD) in patients on MHD. SCI was measured in 59 stable MHD patients. All patients underwent coronary angiography. Significant CAD was defined as a > 70% narrowing in at least one epicardial coronary artery. Levels of SCI were compared with a group of healthy controls. Significant CAD was detected in 22 (37.3%) patients, with one vessel disease in 14 (63.63%) and multi-vessel disease in eight (36.36%) patients. The MHD patients had elevated levels of SCI (4.70 ± 1.79 µmol/L) compared with normal health survey participants (0.11 ± 0.01 µmol/L) (P < 0.0001). MHD patients who had no CAD had SCI levels of 1.36 ± 0.34 µmol/L compared with those having significant CAD (8.92 ± 4.12 µmol/L) (P < 0.0001). Patients on MHD and diabetes had stronger correlation between SCI and prevalence of CAD compared with non-diabetics. Patients having one vessel disease had SCI of 8.85 ± 4.67 µmol/L versus multi-vessel disease with SCI of 9.05 ± 8.34 µmol/L, P = 0.48. In multivariate analysis, SCI and diabetes mellitus were independently associated with significant CAD. We confirm the high prevalence of significant CAD in MHD patients. Elevated SCI levels are associated with presence of significant coronary disease in such patients. The association of SCI is higher in diabetic versus the non-diabetic subgroup. This is an important potentially modifiable biomarker of CAD in MHD patients.

Is carbon dioxide a safe and good alternative for diatrizoate meglumine as a contrast in digital subtraction angiography?

Contrast-induced nephropathy is well-known sequelae of iodinated contrast (diatrizoate meglumine). Carbon dioxide (CO(2)) can be used as an alternative contrast agent. The aim of this study was to compare the renal injury and the quality of images of aortogram using iodinated contrast versus CO(2) using digital subtraction angiography (DSA). This prospective randomized study was done in 29 healthy dogs using DSA aortogram. Dogs were randomly assigned to receive iodinated contrast or CO(2). 6-F pigtail catheter was introduced via femoral artery approach to perform aortogram under general anesthesia. Serum creatinine (S.Cr.) and urinary enzymes, namely: N-acetyl D-glucosaminidase (NAG), alanine aminopeptidase (AAP), and gamma glutamyl transferase (GGT), were measured before and 48 hours after aortogram. There was no change in S.Cr. in both the groups. Significantly more enzymuria was seen following iodinated contrast than CO(2). Enzymuria pre and postaortogram following the iodinated contrast was GGT: 14.9 +/- 5.92 vs. 26.2 +/- 15.1 (P = 0.001), NAG: 1.63 +/- 0.90 vs. 3.6 +/- 2.14 (P = 0.0001), and AAP: 1.51 +/- 0.75 vs. 3.38 2.41 (P = 0.001), and in the CO(2) group was GGT: 15.5 +/- 4.9 vs. 21.1 +/- 9.04 (P = 0.02), NAG: 2.12 +/- 1.06 vs. 3.82 3.27 (P = 0.08), and AAP: 1.28 +/- 0.76 vs. 2.51 +/- 1.72 (P = 0.03). More than 50% increase over the preprocedural value was significantly less following CO(2). Images obtained with iodinated contrast were superior to those with CO(2,) however, the quality of image with CO(2) was adequate for delineation of the renal artery and major branches. Both iodinated contrast and CO(2) cause significant enzymuria. More severe enzymuria (>50% increase) was seen significantly less with the use of CO(2). Quality of images is better with iodinated contrast.