Regional citrate anticoagulation vs systemic heparin anticoagulation for double-filtration plasmapheresis.

INTRODUCTION: Double-filtration plasmapheresis (DFPP) has been utilized for immunomodulation in kidney transplantation. Anticoagulation is important to maintain circuit patency during DFPP. We aimed to compare the efficacy and safety of regional citrate anticoagulation (RCA) with systemic heparin anticoagulation during DFPP in kidney transplant recipients. METHODS: A retrospective cohort study was conducted to compare the efficacy and safety of RCA (RCA-DFPP) to systemic heparin anticoagulation (Hep-DFPP) for DFPP among kidney transplant recipients in a single tertiary center. RESULTS: A total of 112 sessions of DFPP were performed for 23 subjects, of which 62 sessions were RCA-DFPP and 50 sessions were Hep-DFPP. There were 13 sessions (11.6%) of premature circuit clotting, 10 sessions (16.1%) for RCA-DFPP and 3 sessions (6.0%) for Hep-DFPP (P = .10). All premature circuit clotting episodes occurred in subjects who underwent DFPP through a vascular catheter. Premature circuit clotting was associated with the use of a vascular catheter (odds ratio [OR] 14.2, 95% confidence interval [CI] 2.7-73.7; P < .01) and high postfilter ionized calcium (OR 12.7, 95% CI 1.4-112.5; P < .01). There was no major bleeding event. Hep-DFPP was associated with higher occurrence of hypocalcemia (OR 1.1, 95% CI 1.0-1.2; P < .01) and metabolic acidosis (OR 1.4, 95% CI 1.2-2.0; P = .04), while hypomagnesemia was more common for RCA-DFPP (OR 2.9, 95% CI 1.1-7.4; P = .03). CONCLUSION: Amongst kidney transplant patients who receive DFPP therapy, RCA-DFPP may be comparable to Hep-DFPP for the maintenance of circuit patency. Functioning vascular access is vital in avoiding premature clotting of the circuit. Close monitoring of electrolyte imbalances and coagulopathy related to DFPP is recommended.

Outcomes of arteriovenous fistula in elderly patients on maintenance haemodialysis.

BACKGROUND: The optimal vascular access strategy in elderly patients receiving haemodialysis (HD) remains controversial. We aim to report the outcomes of arteriovenous fistula (AVF) in elderly patients initiated on maintenance HD in our centre. METHODS: Medical records of 688 incident patients initiated on HD from 2010 to 2012 in a tertiary centre were retrospectively reviewed. Patients' characteristics and AVF outcomes were compared among those < 65 years (non-elderly), ≥ 65-75 years (early elderly) and ≥ 75 years (late elderly). RESULTS: There were 418 non-elderly, 184 early elderly and 86 late elderly patients. There is a higher proportion of brachiocephalic and brachiobasilic fistula created in the late elderly (24.9% vs. 37.0% vs. 41.8%, p = 0.001). The outcomes of accesses created were comparable in the 3 age groups with similar proportions of functional AVFs (80.4% vs. 79.3% vs. 75.6%, p = 0.832) and comparable 1-, 3- and 5-year primary and secondary patency rates (p = 0.351 and 0.282, respectively). However, a longer maturation time (2.78 vs. 2.86 vs. 3.72 months, p = 0.010) and a higher mean number of interventions to assist maturation of the first AVF were required in late elderly patients (0.19 vs. 0.22 vs. 0.35, p = 0.014). Following AVF creation, median patient survival in the non-elderly, early and late elderly was 65.2 vs. 55.1 vs. 49.8 months respectively. CONCLUSION: AVFs created in elderly patients have comparable outcomes compared to non-elderly patients although more interventions are required to assist maturation with a longer maturation time necessitating early access creation to allow for time needed due to maturation delay.

Understanding factors that influence the demand for dialysis among elderly in a multi-ethnic Asian society.

BACKGROUND: Despite literature suggesting conservative management (CM) is a viable option for elderly comorbid ESRD patients, the vast majority in Singapore receive dialysis. We hypothesized that the high demand for dialysis is driven by 1) lack of knowledge of CM and relative benefits of dialysis to CM, 2) adherence to physician recommendations which favour dialysis, and 3) high subsidies for haemodialysis (HD). METHODS: We tested these hypotheses via a survey, including a discrete choice experiment (DCE), administered to 151 elderly pre-dialysis kidney patients and their family caregivers. RESULTS: Results are consistent with the hypotheses: 40% (95% Confidence Interval (CI) 32-48) of patients and 46% (CI 38-55) of caregivers reported not being aware of CM, and 43% (CI 35-51) of patients and 24% (CI 17-31) of caregivers could not provide information on expected survival for dialysis or CM. Yet, once aware of CM as an option, 54% of patients and 42% of caregivers chose CM. However, if their physician recommended dialysis, 49% (CI 40-58) of patients and 68% (CI 59-77) of caregivers switched their choice. Subsidies on HD further reduced demand for CM by 6 percentage points. CONCLUSIONS: These results reveal that the high demand for dialysis is driven mostly by lack of awareness of CM as an option and by physician recommendations for dialysis over CM.

Metastatic pulmonary calcification: Experience from a single center in Singapore.

Metastatic pulmonary calcification (MPC) was seen in 79% of patients with end-stage renal disease (ESRD) during autopsy. However, it is not commonly diagnosed in vivo. Its pathogenesis is not fully understood. We report a retrospective series of 5 cases of MPC from a single center in Singapore. MPC were diagnosed using radiological or histological features. Mean onset of MPC from diagnosis of ESRD was 22.6 ± 3.1 years. One patient remains asymptomatic. Four patients died, one was related to MPC. All patients had calcifications at the lung apices on radiological studies. Three patients with MPC were diagnosed based on radiological features while 2 had histological features. Four patients underwent parathyroidectomy without radiological changes before parathyroidectomy. Median intact parathyroid hormone of this series was 5.6 pmol/L (IQR 1.3-139.4), alkaline phosphatase 74 U/L (IQR 62-461), calcium 2.10 mmol/L (IQR 1.85-2.40), and phosphate 1.30 mmol/L (IQR 0.87-1.63). The observed low iPTH suggests that MPC might occur in low iPTH. Our case series showed MPC might occur in low iPTH after parathyroidectomy, in contrast to existing literature that suggests MPC is diagnosed in patients with elevated iPTH. Parathyroidectomy does not prevent MPC.

Microbiology and audit of vascular access-associated bloodstream infections in multi-ethnic Asian hemodialysis patients in a tertiary hospital.

BACKGROUND: In view of high mortality and morbidity rates associated with vascular access-associated bloodstream infection (VAABSI) in hemodialysis patients, clinical practice guidelines recommend empiric antibiotic therapy for suspected vascular access-related infections. We aim to describe the microbiology of confirmed VAABSI and evaluate the choice of empiric antibiotics, and whether they are prescribed in concordance with the in-house antibiotic guidelines. METHODS: This was a single-center, retrospective, observational study conducted in a tertiary hospital. All adult hemodialysis patients aged 21 years and above who had confirmed VAABSI with positive blood culture results dated from January 2011 to June 2012 were recruited. Relevant information was retrieved electronically from the hospital patient online database, SCM 5.5 Sunrise Enterprise Gateway. RESULTS: A total of 144 episodes of VAABSI were recorded from 118 patients. Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) accounted for 64.2% (68/106) of the gram-positive infections. Gram-negative organisms grew in 26.4% (38/144) of blood cultures and Pseudomonas aeruginosa was the most common organism isolated. The recommended in-house guideline was used as empiric therapy in 24 episodes of VAABSI (16.7%). Five patients died due to VAABSI and none were prescribed antibiotics in concordance with in-house guidelines. CONCLUSIONS: Empiric antibiotics against MSSA and MRSA, as well as gram-negative organisms, especially P. aeruginosa, should be used in patients with suspected vascular access-related infections in our institution. Monitoring of microbiological profile is necessary to guide timely administration of appropriate empiric antibiotics. Further studies are necessary to evaluate the relationship between adherence to in-house guidelines and patients' outcomes.