Switching temporary hemodialysis catheters to long-term catheters: exchange versus de-novo placement, any difference in line infection?
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BACKGROUND: Shifting from a short-term catheter to a long-term one is done either by removing the old catheter and placing a new long-term one via fresh new puncture site, or by replacing the old catheter with a long-term one over a guidewire. AIM: We aimed to describe our technique in changing a temporary line to a long-term catheter (LTC) over a guidewire and to determine the incidence of line-related infections following this procedure. MATERIALS AND METHODS: A retrospective pilot study was conducted between 2005 and 2010 at the American University of Beirut Hospital. We compared the first group (A), which consisted of 20 patients who underwent exchange of a short-term dialysis catheter with a tunneled one over a guidewire using our technique, to a second group (B) of 60 patients who underwent de-novo LTC placement. The two groups were matched by age, with a follow-up of at least 1 month. RESULTS: The technical success rate of the catheter-conversion procedure was 100%. Our results revealed no significant difference of catheter duration between the two groups, with median duration of 6.5 vs. 4.0 days for group A and group B, respectively (p = 0.21). Moreover, there was also no significant mean time difference between any infection and long term catheter (LTC) insertion among the two groups (p = 0.31). Furthermore, there was no difference of catheter infection between the two groups (p = 0.1). CONCLUSION: We concluded that there was no difference in terms of side effects or risk of infection in the guidewire group when compared to standard technique.
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Prevalence of peripheral vascular calcifications in patients on chronic hemodialysis at a tertiary care center in Beirut: a pilot study.

BACKGROUND: Vascular calcifications are highly prevalent in patients maintained on chronic hemodialysis. They have been linked to numerous risk factors and have been associated with an increased risk of cardiovascular morbidity and mortality. The purpose of this pilot study is to assess the prevalence of vascular calcifications among dialysis patients in our tertiary care center and to identify the associated risk factors. METHODS: In the current study, we reviewed the charts of 43 patients undergoing hemodialysis at our center. We estimated the prevalence of vascular calcifications among dialysis patients using plain X-ray of the hand as the screening tool. We compared patient's characteristics and tried to identify possible risk factors, with a special emphasis on the subgroup of patients with diabetes. RESULTS: Vascular calcifications were prevalent among half of the patients on hemodialysis. Duration of dialysis (p = 0.02), diabetes (p < 0.001), and hypertension (p = 0.01) were highly associated with vascular calcifications. No association was found between vascular calcifications and age, gender, calcium-based phosphate binders, vitamin D supplementation, smoking, and lipid control. In multivariate analyses, diabetes and duration of dialysis were the only independent predictors of vascular calcifications and diabetics developed vascular calcifications earlier than nondiabetics (31 months vs 69 months). CONCLUSION: Vascular calcifications are moderately prevalent among patients undergoing hemodialysis at our center, and were found to be strongly correlated with diabetes and duration of dialysis. A larger, multicenter, prospective study should be conducted at national level, in order to confirm the findings of this study and to identify further modifiable risk factors, to decrease the incidence of vascular calcifications and the incurring cardiovascular morbidity and mortality in our population.

Influence of HLA disparity, immunosuppressive regimen used, and type of kidney allograft on production of anti-HLA class-I antibodies after transplant and occurrence of rejection.

We studied the effects of HLA disparity, immunosuppressive regimen used, and the type of kidney allograft on production of anti-HLA antibodies after transplant and the occurrence of rejection episodes. Five living-unrelated donors and 4 living-related donors kidney recipients received quadruple therapy (including sirolimus and mycophenolate mofetil). Fifteen living-unrelated donors and 19 living-related donors received triple therapy (excluding sirolimus). A single bolus of 4 to 6 mg/kg rabbit anti-human T-lymphocyte immune serum was included with both regimens. Recipients were studied over a 3-year period. Human leukocyte antigen profiles were determined by DNA (SSP) typing, and anti-HLA class-I antibodies were determined by the complement-dependent microcytotoxicity assay and an enzyme-linked immunosorbent assay. The degree of HLA disparity did not appear to affect anti-HLA antibody production or the occurrences of rejection episodes. None of the patients who received quadruple therapy developed anti-HLA class-I antibodies. Two living-unrelated donors and 2 living-related donors recipients who received triple therapy developed anti-HLA class-I antibodies. One of the 2 living-unrelated donors antibody-positive patients rejected the kidney and returned to dialysis, and the other patient has normal graft function 3 years after the transplant. The 2 living-related donors patients with normal graft function were antibody-positive 1 year after the transplant but were antibody-negative at 2 and 3 years after transplant. Sirolimus appeared to inhibit production of antibodies after transplant. Moreover, use of present day immunosuppressive agents diminishes the role of HLA matching in relation to the occurrence of rejection episodes.

High-output cardiac failure secondary to a large arteriovenous fistula: a persistent threat to the dialysis and kidney transplant patient.

High-output cardiac failure secondary to a surgically constructed arteriovenous fistula (AVF) is a rare entity that is usually under-diagnosed in the dialysis population. We herein present a case of a 35-year-old female who was diagnosed with high-output cardiac failure secondary to an AVF and later managed with surgical division of the fistula. Risk factors associated with this entity are discussed, and preventive screening strategies are recommended.