Novel renal replacement strategies for the elimination of serum free light chains in patients with kappa light chain nephropathy

Comparison between on-line high-efficiency hemodiafiltration and conventional high-flux hemodialysis for polyclonal free light chain removal

BACKGROUND

Polyclonal free light chains (FLC) are considered as middle molecular weight uremic toxins in chronic kidney disease. In this study, we investigate polyclonal FLC removal by comparing conventional high-flux hemodialysis (HD) and online high-efficiency hemodiafiltration (ol-HDF) in end-stage renal disease patients.

METHODS

We analyzed 31 chronic dialysis patients who were treated by HD then by postdilution ol-HDF during a prospective study. All patients were anuric and without monoclonal gammopathy. Serum pre- and postdialysis FLC were collected during 4 sessions: 1 HD session and 3 ol-HDF sessions. We calculated the reduction ratio using kinetic modeling.

RESULTS

The κ reduction ratio was higher with ol-HDF than with HD (66 ± 14 vs. 52 ± 13%, p < 0.001). However, the λ reduction ratio was not significantly higher with ol-HDF (37 ± 20 vs. 37 ± 15%, p = 0.67). Furthermore, predialysis κ- and λ-FLC increased with ol-HDF compared with HD (κ 155 ± 82 vs. 87 ± 47 mg/l, p < 0.05; λ 101 ± 46 vs. 72 ± 41 mg/l, p < 0.05). Postdialysis FLC levels were raised only for λ-FLC with ol-HDF (74 ± 39 vs. 53 ± 31 mg/l, p < 0.05) and were not significantly different for κ.

CONCLUSIONS

This study shows that κ-FLC removal is better in ol-HDF compared with HD, whereas there is no difference in λ-FLC removal. Surprisingly, predialysis κ and λ levels are both increased in ol-HDF, which is disturbing since polyclonal excess of λ-FLC is associated with mortality in chronic kidney disease.

Endotoxemia after high cutoff hemodialysis for treatment of patient with multiple myeloma can be prevented by using ultrapure dialysate: a case report

To report endotoxemia presented in a case with multiple myeloma (MM) treated by high cutoff hemodialysis (HCO-HD) being prevented by using ultrapure dialysate. A female inpatient with MM received six times HCO-HD (HCO 2100 dialyzer) within 3 weeks after initiation of a chemotherapy based on vincristine+epirubicin+dexamethasone protocol. Conventional dialysate was used in the first three times and then changed to ultrapure dialysate due to elevation of body temperature after HCO-HD. Free light chains (FLC) and endotoxin levels in blood and dialysate were monitored. After six times HCO-HD, her serum FLC λ decreased from 4689 mg/L to 492.7 mg/L, with a trend of decline of serum creatinine. The clearance, reduction ratio, and removal amount of FLC λ was 38.4 mL/min, 71.0-85.2%, and 9.06-18.02 g, respectively, in the setting of dialysate flow rate 500 mL/min, while in the setting of dialysate flow rate 200 mL/min, the removal efficacy of FLC λ was lower than the former. A rise of body temperature up to 38.5°C after treatment and endotoxemia (endotoxin levels 0.122 EU/mL) was found when using conventional dialysate (endotoxin levels 0.112-0.145 EU/mL), but not seen after changing to ultrapure dialysate. Combined with appropriate chemotherapy, HCO-HD can effectively remove and reduce blood FLC. Attention should be paid to the endotoxemia and the rise of temperature after treatment when conventional dialysate is used, which can be prevented by using ultrapure dialysate.

Impact of free light chain hemodialysis in myeloma cast nephropathy: a case-control study

New very high permeability dialysis membranes have been developed to enable the clearance of free light chains in myeloma cast nephropathy. These new dialysis techniques, in combination with chemotherapy, should allow improved prognosis in patients with myeloma cast nephropathy. We report a prospective observational study comparing patients who underwent hemodialysis in our center in 2009 for cast nephropathy revealing multiple myeloma vs. patients treated for the same condition during the same period in other centers in our region. The main difference in the management protocols was the use of high cutoff (HCO) membranes in our center. We described the clinical features, the management protocols, and the outcomes as of June 1, 2010. In 2009, five patients were treated for myeloma cast nephropathy with HCO hemodialysis in our center. At 386 ± 100 days follow-up, one patient died, while three of the five patients recovered their renal function, allowing cessation of hemodialysis. During the same period, five patients were treated for myeloma cast nephropathy in other centers in our region. At 398 ± 131 days follow-up, four patients died, and none of the patients recovered renal function, allowing cessation of hemodialysis. In our study, light chain clearance allowed recovery of renal function and cessation of hemodialysis in three of five patients with acute kidney injury secondary to myeloma cast nephropathy. A randomized trial comparing this technique with conventional hemodialysis techniques should be conducted to raise the level of proof for this therapeutic option. The overall prognosis, including quality of life and cost-effectiveness, of HCO hemodialysis should also be examined.

Bendamustine in patients with relapsed or refractory multiple myeloma

Objective

In patients with multiple myeloma, bendamustine monotherapy is effective as 1^st and 2^nd line therapy. However, data for patients with advanced multiple myeloma is rare.

Methods

In this retrospective analysis we have identified 39 patients with relapsed or refractory multiple myeloma by means of case research, who have been treated at our institution with bendamustine as salvage therapy. After in median 2 lines of prior therapy (range:1-5) patients received in median 3 (range: 1-10) cycles of bendamustine. Bendamustine dosage was 80-150 mg on day 1+2 of a monthly cycle. Bendamustine was administered as monotherapy in 39% of patients, whereas 61% received concomitant steroids.

Results

Toxicity was mild to moderate. Response rates were as follows: 3% vgPR, 33% PR, 18% MR, 26% SD and 20% PD. The median event-free and overall survival were 7 and 17 months, respectively.

Conclusions

In conclusion, in patients with advanced multiple myeloma bendamustine is effective and associated with mild toxicity. Therefore, the role of bendamustine in patients with multiple myeloma should be investigated in further clinical trials.