Comparison of survival between dialysis patients with incident high-flux hemodialysis versus on-line hemodiafiltration: A single center experience in Saudi Arabia.

Conventional hemodialysis (HD) is the most common treatment modality used for renal replacement therapy. The concept of HD is based on the diffusion of solutes across a semipermeable membrane. Hemofiltration (HF) is based on convective transport of solutes; hemodiafiltration (HDF) is based on combined convective and diffusive therapies. Data about survival benefit of on-line HDF (OL-HDF) over high-flux HD (HF-HD) is conflicting. We conducted this study to investigate if there is a survival difference between the two treatment modalities. This study is a retrospective, single-center study in which 78 patients were screened; 18 were excluded and 60 patients were analyzed. The study patients were aged 47.5 ± 20.7 years, 33 patients (55%) were on HF-HD, and 27 patients (45%) were on OL-HDF. A total of 24 patients (40%) of both groups were diabetic and, the mean duration on dialysis was 43.5 ±21.3 months in the HF-HD group and 41.2 ± 22.0 months in the OL-HDF group. The mean substitution volume for OL-HDF was 22.3 ± 2.5 L. Survival was 73% [95%, confidence interval (CI) 60-84] in the HF-HD group and 65% (95%, CI 54-75) in the OL-HDF group by the end of the study period. The unadjusted hazard ratio (HR) with 95% CI comparing HF-HD to high-volume postdilution OL-HDF was 0.78 (0.10-5.6; P = 0.810). Kaplan-Meier analysis for patient survival over five years showed no significant difference between the two modalities. Prospective controlled trials with a larger number of patients will be needed to assess the long-term clinical outcome of postdilution OL-HDF over HF-HD.

Vascular access types in patients starting hemodialysis after failed kidney transplant: does close nephrology follow-up matter?

BACKGROUND: Native arteriovenous fistulae (AVFs) are preferred while central venous catheters (CVCs) are least suitable vascular access (VA) in patients requiring hemodialysis (HD). Unfortunately, around 80% of patients start HD with CVCs. Late referral to nephrologist is thought to be a factor responsible for this. We retrospectively analyzed the types of VA at HD initiation in renal transplant recipients followed by nephrologists with failed transplant. If early referral to nephrologist improves AVF use, these patients should have higher prevalence of AVF at HD initiation. METHODS: All patients who failed their kidney transplants from January 2002 to April 2013 were included in the study. Data regarding planning of VA by nephrologist, documented discussion about renal replacement therapy (RRT), estimated glomerular filtration rate (eGFR) at 6 months and last clinic visit before HD initiation, time of VA referral, and subsequent VA at dialysis initiation were gathered and analyzed. RESULTS: Eighty-three patients failed their transplants during study period. Data were inaccessible in six patients. Eleven patients started peritoneal dialysis (PD) while 66 started HD. Thirty-two had previous functioning VA while 34 needed VA. There were 11/34 patients (32%) with eGFR <15 mL/min at six months while 21/34 (61%) had eGFR <15 mL/min at last clinic visit before HD initiation. Only 11/34 (32%) had documented RRT discussion, 8/34 (24%) had VA referral, and 7/34 (21%) had vein mapping. A total of 30/34 (88.3%) started HD with CVC while 4/34 (11.3%) started HD with AVF (p<0.0001). CONCLUSIONS: Early referral to nephrologist by itself may not improve VA care amongst patient with end-stage renal disease.

Chromophobe renal cell carcinoma occurring in the renal allograft of a transplant recipient presenting with weight loss.

The incidence of renal cell carcinomas (RCCs) in renal transplant recipients is reported as 1.1-1.5% in the native kidneys and 0.22-0.25% in the renal allograft. There are no data to support routine surveillance for tumors in transplant recipients. Most reported cases of RCCs occurring in renal allografts were incidental findings in asymptomatic patients. Herein, we report the second case of lone chromophobe RCC (ChRCC) of the renal allograft presenting with weight loss. Loss of weight is a presenting symptom in one-third of ChRCCs occurring in the native kidneys in the general population. Based on the age of the patient, R.E.N.A.L nephrometry score of the tumor and the lack of data on the prognosis of this histological subtype in a climate of long-term immunosuppression, we elected for radical nephrectomy. We suggest that RCCs should be considered in the differential diagnosis of a transplant recipient presenting with weight loss even in the absence of localizing symptoms or signs.

Proteomic analysis of Class IV lupus nephritis.

BACKGROUND: There have been several attempts to standardize the definition and increase reproducibility in classifying lupus nephritis (LN). The last was made by the International Society of Nephrology and Renal Pathology Society in 2003 where the introduction of Class IV subcategories (global and segmental) was introduced. METHODS: We investigated whether this subdivision is important using a proteomics approach. All patients with renal biopsies along with their clinical outcome of LN were identified and regrouped according to the above 2003 classifications. Fresh-frozen renal biopsies of Class IV LN (global and segmental), antineutrophil cytoplasmic antibody-associated vasculitis and normal tissue were analyzed using two-dimensional gel electrophoresis (2-DE) and mass spectrometry. Differentially expressed proteins were identified and subjected to principal component analysis (PCA), and post hoc analysis for the four sample groups. RESULTS: PCA of 72 differentially expressed spots separated Class IV global and Class IV segmental from both normal and antineutrophil cytoplasmic antibody-associated vasculitis (ANCA). The 28 identified proteins were used in a post hoc analysis, and showed that IV-global and IV-segmental differ in several protein expression when compared with normal and ANCA. To confirm the proteomic results, a total of 78 patients (50 Class IV-Global and 28 Class IV-Segmental) were re-classified according to 2003 classification. There was no difference in therapy between the groups. The renal survival and patient survivals were similar in both groups. CONCLUSIONS: There is no strong evidence to support a different outcome between the two subcategories of Class-IV LN and, they should thus be treated the same until further studies indicate otherwise.

Cyclosporine versus tacrolimus maintenance therapy in renal transplant.

OBJECTIVES: Several studies have shown comparable results in long-term graft and patient survival, comparing a tacrolimus-based therapy to cyclosporine, while other studies have shown that a tacrolimus-based regimen had a better renal function with fewer episodes of acute rejection. Most of these studies were in a white population. We describe our experiences comparing tacrolimus versus cyclosporine maintenance therapy in a Saudi population. MATERIALS AND METHODS: All patients from 2003 until 2008 in our transplant clinic were evaluated. A retrospective analysis was done comparing patient and graft survival, kidney function, and metabolic profile. RESULTS: There was no statistical difference in acute rejection rate between the cyclosporine group and the tacrolimus group (18.7% vs 20.9%; P = .756). Mean serum creatinine was not statistically different between the 2 groups. Patient and graft survival at 1 and 2 years also were similar. Although patient and graft survival were similar, the cyclosporine group had a higher level of cholesterol compared with the tacrolimus group (4.6 ± 1.03 mmol/L vs 4.1 ± 0.80 mmol/L; P = .010). CONCLUSIONS: There is no difference in 1- or 2-year patient and graft survival between patients maintained on cyclosporine compared with tacrolimus. However, patients on cyclosporine had a higher blood pressure and serum cholesterol level.