Increased nitric oxide production during acute rejection in kidney transplantation: a useful marker to aid in the diagnosis of rejection.

BACKGROUND: The diagnosis of acute rejection (AR) relies on biopsy (Bx), with all the noninvasive tests failing to show satisfactory predictive value. Nitric oxide (NO) has been shown to play a role in AR. The aim of this study is to analyze the relationship between NO and (1) biopsy-proven allograft rejection and (2) other reasons of allograft dysfunction. PATIENTS AND METHODS: Fifty consecutive renal allograft recipients ages 23-72 yrs who were transplanted were prospectively recruited. Blood samples were collected for 3 months. Endogenous serum nitrate (SNO(3)) levels were measured with Griess reagent in 1178 samples. Biopsies were performed as clinically indicated. Tacrolimus levels, urinary cultures, and renal function tests were done as per unit protocol. RESULTS: Fifty recipients (mean+/-SD age 45.2+/-2.18 yrs, 24 men and 6 women) underwent 68 biopsies. Forty-five Bx (66.2%) showed AR in 19 recipients (mean age 47+/-8) and 23 (33.8%) Bx in 13 recipients (mean age 43+/-12) showed no AR. SNO(3) in AR was (73+/-8.89 micromol/L) compared with negative Bx (45+/-4.5 micromol/L; P<0.05). There was also a significant difference in SNO(3) during AR and other causes of allograft dysfunction; delayed graft function (54+/-7.8 micromol/L), urinary tract infection (44+/-2.9 micromol/L), tacrolimus toxicity (51+/-2.86 micromol/L), and increase in serum creatinine (44+/-2.36 micromol/L). CONCLUSION: There is a significant increase of serum nitrate with episodes of acute rejection compared with other causes of renal dysfunction. SNO(3) can therefore aid in the diagnosis of acute rejection.

Lack of motivation: a new modifiable risk factor for peritonitis in patients undergoing peritoneal dialysis?

AIM: Can we identify modifiable risk factors for peritonitis in patients undergoing peritoneal dialysis (PD)? We aimed to determine whether housing standard, PD exchange technique or patient motivation might be modifiable risks for peritonitis. We also explored the relationship between lack of motivation and depression. METHODS: Nurse home visits assessed PD exchange technique, environment and patient motivation. Motivation scores were correlated separately with an Apathy Evaluation Score and a depression score using PHQ-9 questionnaires. RESULTS: Home hygiene, exchange technique and motivation were above average in 53%, 56% and 60%, respectively in 104 patients undergoing PD. After 15 months, 25.9% patients developed peritonitis but nurses' ratings of homes and exchange techniques were not predictive. Low patient motivation was predictive. Patients rated to have above or below median motivation had significantly different Apathy Scores (p = 0.0002). Unmotivated depressed patients were significantly more likely to develop peritonitis compared to motivated depressed patients. CONCLUSION: Lack of motivation predicted peritonitis particularly if associated with depression. Further studies are required focusing on specific motivation scoring schemes and the psychosocial support that might lead to better outcomes.

Endovascular repair of symptomatic hemodialysis access graft pseudoaneurysms.

AIM: Repeated needle punctures of arteriovenous hemodialysis grafts can lead to the development of pseudoaneurysms. As they enlarge, graft pseudoaneurysms are associated with significant morbidity and require treatment. We present our single-center experience using stent grafts in selected patients to exclude symptomatic hemodialysis graft pseudoaneurysms. MATERIALS AND METHODS: Between March 2007 and December 2010, 11 consecutive patients (7 men and 4 women, mean age 57 years) underwent percutaneous endovascular repair of symptomatic hemodialysis access graft pseudoaneurysms. Indications for treatment were rapidly enlarging pseudoaneurysm in 5 patients, high venous pressures, limb edema and pseudoaneurysm in 3, skin breakdown over the pseudoaneurysm site in 2 and acute rupture and bleeding in 1 patient. No patient was lost to follow-up. RESULTS: Technical success across the 11 patients was 90.9%. The patient who presented with rupture required ligation of the access due to continuous bleeding after stent graft insertion. Balloon angioplasty of a separate hemodynamically significant stenosis at the time of stent graft insertion was performed in 7 of 11 (63.6%) patients. The primary access patency rates were 72.7% (95% CI of 0.390-0.939) at 3 months and 36.4% (95% CI 0.109-0.692) at 6 months. Secondary access patency rates were 72.7% at 6 months (95% CI 0.233-0.832). There were no procedure-related complications. Mean follow-up was 9 months (range 2-29 months). CONCLUSIONS: Endovascular treatment of symptomatic hemodialysis graft pseudoaneurysms is safe and effective with similar patency rates to surgical approaches. Importantly, this approach allows aggressive management of associated access circuit stenoses at the same time and avoids interval tunneled dialysis line insertion.

Cephalic arch stenosis in autogenous haemodialysis fistulas: treatment with the viabahn stent-graft.

PURPOSE: Cephalic arch stenosis (CAS) is an important and common cause of dysfunction in autogenous haemodialysis fistulas that requires multiple reinterventions and aggressive surveillance. We evaluated the safety and efficacy of the Viabahn stent-graft for the management of CAS. METHODS: Between April 2005 and October 2011, 11 consecutive patients [four men and seven women (mean age 56.7 years)] with CAS and dysfunctional fistulas were treated with insertion of 11 Viabahn stent-grafts. Six stent-grafts were inserted due to residual stenosis after angioplasty and five for fistuloplasty-induced rupture. No patient was lost to follow-up. RESULTS: The technical and clinical success rate was 100 %. Primary access patency rates were 81.8 % [95 % confidence interval (CI) 0.482-0.977] at 6 months and 72.7 % (95 % CI 0.390-0.939) at 12 months. Secondary access patency rates were 90.9 % at 6 months (95 % CI 0.587-0.997). There were no procedure-related complications. Mean follow-up was 543.8 days (range 156-2,282). CONCLUSION: The use of the Viabahn stent-graft in the management of CAS is technically feasible and, in this small series, showed patency rates that compare favorably with historical data of angioplasty and bare stents.

Lanthanum associated abnormal liver function tests in two patients on dialysis: a case report.

Lanthanum (La) is a phosphate binder used in patients on dialysis in the UK. As it has only recently been in use, there are no long-term data about safety of this rare metal in human subjects with renal failure on renal replacement therapy. La has not been previously reported to cause any adverse reactions apart from nausea, sickness, dialysis graft occlusion and abdominal pain. We report here La induced abnormal liver function tests in a male and a female patient of 70 and 44 years old each, on peritoneal dialysis (PD) and haemodialysis (HD) respectively, the first report of such an adverse reaction to this agent.