Non-surgical salvage of thrombosed arterio-venous fistulae: a case series and review of the literature.

Attempts to salvage thrombosed hemodialysis arterio-venous fistulae (AVF) using interventional techniques are not universally performed. Patients often require temporary dialysis catheters pending creation of a new vascular access. We determined the long-term outcome of interventional (non-surgical) repair of completely thrombosed AVF in 49 consecutive accesses (22 radio-cephalic, 1 radio-basilic, 19 brachio-cephalic, and 7 brachio-basilic) referred for an intervention within 48 hours of thrombosis. Subjects were 65% male (32), with mean +/- SD age 63.7 +/- 13.5 years (range 33-91), 51% African-American (25), 47% Caucasian (23) and 65% had diabetes (32). Overall, 96% (47/49) of thrombosed AVF were salvaged with complications observed in four cases (two extravasations of contrast; two radial artery emboli), with no serious long-term sequelae. Interventional procedures included 34 venous angioplasties, 11 venous angioplasties with stenting and two combined venous and arterial angioplasties. The primary and secondary patency rates for all salvaged AVF were 50.5 +/- 8.7%, 72.5 +/- 7.8% at 1 year, and 43.3 +/- 10%, 55.4 +/- 12.7% at 2 years, respectively. The median estimate to first intervention after the declot procedure was 14.7 months. The median estimate for continued function exceeded 23.1 months. There was no significant statistical difference in the primary (p = 0.73) and secondary patency rates (p = 0.057) for forearm vs. upper arm AVF. We conclude that interventional repairs should routinely be employed to salvage newly thrombosed AVF. The vast majority of these individuals can avoid receiving dialysis catheters or placement of a new dialysis vascular access.

A leucine repeat in the carnosinase gene CNDP1 is associated with diabetic end-stage renal disease in European Americans.

BACKGROUND: Four linkage analyses have identified a region on chromosome 18q22-23 that appears to harbour a diabetic nephropathy (DN) susceptibility locus. A trinucleotide repeat sequence in exon 2 of the carnosinase gene (CNDP1) residing on 18q22.3 was subsequently associated with DN in European Caucasians and Arabs. METHODS: We evaluated the role of the CNDP1 5 leucine/5 leucine (5-5) polymorphism (CNDP1 Mannheim) in diabetic end-stage renal disease (ESRD) susceptibility in 858 European Americans: 294 with type 2 DN-associated ESRD (DN-ESRD), 258 with diabetes mellitus (DM) lacking nephropathy and 306 healthy controls. RESULTS: Subjects with DM lacking nephropathy were significantly more likely to be homozygous for the 5-leucine repeat CNDP1 genotype (5-5), compared with those with DN-ESRD (P=0.02). Healthy controls were also more likely to be homozygous for the 5-5 genotype, compared with those with DN-ESRD (P=0.008). No significant difference in 5-5 genotype frequency was observed between healthy controls and DM cases without nephropathy (P=0.74). CONCLUSION: European Americans homozygous for the 5-5 leucine repeat polymorphism in the CNDP1 gene are at significantly reduced risk for developing diabetic ESRD. This replicates the CNDP1 gene association with DN that was initially detected in European Caucasians and in Arabs, and further demonstrates that the CNDP1 gene and carnosine pathway appear to play a role in susceptibility to DN.