背景:脂蛋白X(Lp-X)是在多种疾病中发现的异常脂蛋白,包括肝功能障碍和胆汁淤积。高Lp-X浓度会干扰一些实验室测试,这可能导致虚假结果。Lp-X的检测具有挑战性,除了治疗基础疾病外,目前对于Lp-X的治疗缺乏共识.
方法:一名42岁女性霍奇金淋巴瘤患者接受地塞米松治疗,大剂量阿糖胞苷和顺铂和肝活检证实胆管消失综合征表现为胆汁淤积,假性低钠血症(钠,113mmol/L;参考范围136-146mmL/L;血清渗透压,303mOsm/kg),和高胆固醇血症(>2800毫克/分升,参考范围<200mg/dL)。脂蛋白电泳(EP)证实Lp-X。尽管她没有表现出任何特定的体征或症状,治疗性血浆置换(TPE)是根据极端高胆固醇血症的实验室结果启动的,虚假异常的血清钠,和HDL值,以及高粘血症等短期和长期后遗症的可能性,黄色瘤,和神经病。住院期间,她在6天内接受了4例1.0血浆容量的TPE治疗,使用5%白蛋白作为替代液.在第一次TPE之后,总胆固醇(TC)降至383mg/dL,钠在131mmol/L时测得在治疗基础疾病的同时,将患者转变为门诊维持TPE以消除Lp-X重新出现的可能性。使用脂蛋白EP进行的连续随访实验室测试显示,在10周内进行了9次TPE后,Lp-X消失。
方法:有7例和4例Lp-X用TPE和脂蛋白单采术(LA)治疗,分别。虽然以前的所有病例报告都显示TC水平降低,在完成一个疗程的治疗性单采手术后,没有人监测到Lp-X的消失。
结论:临床医生应高度怀疑胆汁淤积患者存在异常Lp-X,高胆固醇血症,和假性低钠血症.一旦Lp-X被脂蛋白EP证实,应启动TPE以降低TC水平并消除异常Lp-X。由于Lp-X缺乏载脂蛋白B,因此大多数LA技术预计不会有益。我们建议每隔一天进行一次TPE的住院疗程,直到血清钠,TC和HDL水平变得标准化。门诊维持TPE也可以被认为在治疗潜在疾病时保持Lp-X水平低。血清钠,TC,在维持TPE时,应监测HDL水平。
BACKGROUND: 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.
METHODS: 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.
METHODS: 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.
CONCLUSIONS: 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.