Use of therapeutic plasma exchange to remove lipoprotein X in a patient with vanishing bile duct syndrome presenting with cholestasis, pseudohyponatremia, and hypercholesterolemia: A case report and review of literature.

INTRODUCTION: Lipoprotein X (Lp-X) is an abnormal lipoprotein found in multiple disease conditions, including liver dysfunction and cholestasis. High Lp-X concentrations can interfere with some laboratory testing that may result in spurious results. The detection of Lp-X can be challenging, and there is currently a lack of consensus regarding the management of Lp-X other than treating the underlying disease. CASE PRESENTATION: A 42-year-old female with Hodgkin's lymphoma treated with dexamethasone, high dose cytarabine and cisplatin and vanishing bile duct syndrome confirmed by liver biopsy presented with cholestasis, pseudohyponatremia (sodium, 113 mmol/L; reference range 136-146 mmL/L; serum osmolality, 303 mOsm/kg), and hypercholesterolemia (> 2800 mg/dL, reference range < 200 mg/dL). Lp-X was confirmed by lipoprotein electrophoresis (EP). Although she did not manifest any specific signs or symptoms, therapeutic plasma exchange (TPE) was initiated based on laboratory findings of extreme hypercholesterolemia, spuriously abnormal serum sodium, and HDL values, and the potential for short- and long-term sequelae such as hyperviscosity syndrome, xanthoma, and neuropathy. During the hospitalization, she was treated with four 1.0 plasma volume TPE over 6 days using 5% albumin for replacement fluid. After the first TPE, total cholesterol (TC) decreased to 383 mg/dL and sodium was measured at 131 mmol/L. The patient was transitioned into outpatient maintenance TPE to eliminate the potential of Lp-X reappearance while the underlying disease was treated. Serial follow-up laboratory testing with lipoprotein EP showed the disappearance of Lp-X after nine TPEs over a 10-week period. LITERATURE REVIEW: There are seven and four case reports of Lp-X treated with TPE and lipoprotein apheresis (LA), respectively. While all previous case reports showed a reduction in TC levels, none had monitored the disappearance of Lp-X after completing a course of therapeutic apheresis. CONCLUSION: Clinicians should have a heightened suspicion for the presence of abnormal Lp-X in patients with cholestasis, hypercholesterolemia, and pseudohyponatremia. Once Lp-X is confirmed by lipoprotein EP, TPE should be initiated to reduce TC level and remove abnormal Lp-X. Most LA techniques are not expected to be beneficial since Lp-X lacks apolipoprotein B. Therefore, we suggest that inpatient course of TPE be performed every other day until serum sodium, TC and HDL levels become normalized. Outpatient maintenance TPE may also be considered to keep Lp-X levels low while the underlying disease is treated. Serum sodium, TC, and HDL levels should be monitored while on maintenance TPE.

Effect of high nucleated cell concentration on product viability and hematopoietic recovery in autologous transplantation.

BACKGROUND: Administering lower total product volumes with high nucleated cell (NC) concentrations may have the potential benefit of decreasing volume- and dimethyl sulfoxide (DMSO)-related patient complications, while maximizing the laboratory's freezer storage capacity. Our study is a retrospective investigation of the effect of HPC(A) products with cell concentrations greater than 3 × 108 NC/mL on clinical and product outcomes in patients undergoing autologous peripheral blood stem cell (PBSC) transplantation. STUDY DESIGN AND METHODS: A total of 113 consecutive patients with hematological malignancies who underwent autologous PBSC transplantation were included in this retrospective analysis. The primary outcomes were days to initial absolute neutrophil count (ANC) recovery and initial platelet recovery. The secondary outcomes included the storage duration, segment thaw viability, and dose of viable CD34+ cells/kg administered. RESULTS: Of 92 patients and 176 apheresis procedures, 81 patients received HPC(A) products with high NC concentration (4.1 × 108 NC/mL), and 11 patients received low NC concentration products (2.4 × 108 NC/mL). There were no observed differences in clinical outcomes with respect to ANC recovery (14 vs. 14 vs. 12 days) and platelet recovery (16 vs. 16 vs. 15 days) when very high NC (5.2 × 108 NC/mL) and high NC (4.1 × 108 NC/mL) groups were compared to the low NC group (2.4 × 108 NC/mL). CONCLUSION: Our retrospective investigation provides further supporting evidence that HPC(A) products with cell concentration greater than 3 × 108 NC/mL did not show detrimental effects on the clinical outcomes in patients undergoing autologous PBSC transplantation.