Albumin losses during hemodiafiltration: all dialyzers are not created equal - a case report.

BACKGROUND: Online hemodiafiltration (OL-HDF) is associated with better removal of both small and middle molecules and might improve survival compared to conventional hemodialysis (HD). Nevertheless, hemodiafiltration (HDF) can lead to an increase in albumin loss across the dialyzer, especially with high permeability membrane and high convective volume (CV). We present the case of a patient treated by OL-HDF who developed severe hypoalbuminemia resulting from massive albumin loss into dialysate. CASE PRESENTATION: A 71-year-old woman with ESRD started renal replacement therapy in December 2016. She was treated by high volume post-dilution OL-HDF, 4 h, 3 times per week. The dialyzer was the Phylther HF20SD (a 2.0m2 heat sterilized high flux (HF) polyphenylene membrane from Bellco). At the initiation of dialysis, the serum albumin was 4.0 g/dl. During the following months, the patient developed severe hypoalbuminemia. The lowest value observed was 2.26 g/dl in July 2017. Diagnostic workup excluded nephrotic syndrome, hepatic failure and malabsorption. The patient was shifted from OL-HDF to standard HF HD, keeping the same dialyzer and dialysis schedule. During the following months, we observed a progressive correction of the hypoalbuminemia (3.82 g/dl at last follow-up). To precise the impact of the epuration technique on the albumin losses in this patient, we measured the amount of albumin in dialysate during one session with the Phylther HF20SD on OL-HDF and one session with the same filter but on standard HD. The CV was 29.0 l for the HDF session. The total albumin losses were 23.6 g on OL-HDF and 4.6 g on HD. CONCLUSION: OL-HDF can lead to significant albumin loss into the dialysate, especially with high permeability membrane and high CV. When prescribing post-dilutional OL-HDF, the choice of the dialyzer membrane should be made with caution. Users of the steam sterilized polyphenylene membrane, the Phylther SD, should be informed of the risk of large albumin loss with this membrane during post-dilution OL-HDF.

Cutaneous Mycobacterium chelonae infection distal to the arteriovenous fistula.

A few single cases of Mycobacterium chelonae skin infection have been reported in haemodialysis patients. We report three additional cases that share peculiar clinical characteristics, pointing to diagnostic clues. All three cases presented as erythematous nodules developing distally to a proximal arteriovenous fistula (AVF). This presentation was identical to that of two published cases. A survey of all Belgian haemodialysis units during the period 2007-11 yields an estimated incidence of ∼0.9/10 000 patient-years. Although the source of M. chelonae remains unclear, this specific clinical presentation should be added to the listing of potential complications of an AVF and should be recognized, as it is fully treatable if diagnosed by culture and tissue biopsy.

Proton-pump inhibitors do not influence serum magnesium levels in renal transplant recipients.

Severe hypomagnesemia has been reported with use of proton-pump inhibitors (PPIs). We assessed the effect, if any, of PPI use on serum magnesium level in a cross-sectional analysis of a large published cohort of renal transplant recipients (RTRs). Between February 2004 and February 2006, 512 consecutive prevalent RTRs were enrolled at two university hospitals in Belgium (Brussels and Ghent). Serum creatinine was 1.5 ± 0.7 mg/dl, and estimated glomerular filtration rate (eGFR) 53 ± 19 ml/min/1.73 m(2). Mean (and median) magnesium level was 1.91 ± 0.23 mg/dl. PPIs were prescribed in 20 % (n = 101) of cases. At multivariable analysis, PPI use was not an independent predictor of serum magnesium level or hypomagnesemia. The independent predictors of a lower serum magnesium level were the use of tacrolimus, cyclosporin and sirolimus, the absence of use of mycophenolate mofetil, lower levels of parathyroid hormone and higher eGFR. This study is the first to analyze the potential impact of PPIs on magnesium level in a large, representative cohort of RTR patients. Our results suggest that PPIs may be used without particular fear of favoring hypomagnesemia-related side effects in RTRs, an important finding in a population at high risk of hypomagnesemia.