Abstract:
Background: Light-chain proximal tubulopathy (LCPT) is a rare disease characterized by the accumulation of monoclonal light chains within proximal tubular cells. This study aimed to investigate the clinical characteristics of LCPT from a single Chinese nephrology referral center.Methods: Patients with kidney biopsy-proven isolated LCPT between 2016 and 2022 at Peking University First Hospital were retrospectively included. Clinical data, kidney pathological type, treatment, and prognosis were analyzed.Results: Nineteen patients were enrolled, the mean age at diagnosis was 57 ± 11 and the sex ratio was 6/13 (female/male). Mean proteinuria was 2.44 ± 1.89 g/24 hr and the mean estimated glomerular filtration rate (eGFR) at the point of biopsy was 59.640 ± 27.449 ml/min/1.73 m2. κ-restriction (84%) was dominant among LCPTs. An abnormal free light chain ratio was observed in 86% of the patients. Proximal tubulopathy with cytoplasmic inclusions accounted for the majority (53%), followed by tubulopathy associated with interstitial inflammation reaction (26%), proximal tubulopathy without cytoplasmic inclusions (16%), and proximal tubulopathy with lysosomal indigestion/constipation (5%). One patient presented with acute kidney injury and 16 patients presented with chronic kidney disease. Regarding follow-up, patients received bortezomib-based or R-CHOP chemotherapy or supportive treatment only. The mean follow-up time was 22 ± 16 months, and the mean eGFR was 63.098 ± 27.439 ml/min/1.73 m2 at the end of follow-up. These patients showed improved or stable kidney function.Conclusions: This is the first case series report of LCPT in four different pathological types in northern China. Clone-targeted chemotherapy may help preserve the kidney function in these patients.
摘要:
背景:轻链近端肾小管病(LCPT)是一种罕见的疾病,其特征是单克隆轻链在近端肾小管细胞内积累。本研究旨在探讨中国单一肾内科转诊中心LCPT的临床特点。方法:回顾性分析2016-2022年北京大学第一医院肾活检证实的孤立性LCPT患者。临床数据,肾脏病理类型,治疗,并对预后进行分析。结果:共纳入19例患者,诊断时的平均年龄为57±11岁,性别比例为6/13(女性/男性).平均蛋白尿为2.44±1.89g/24小时,活检点的平均估计肾小球滤过率(eGFR)为59.640±27.449ml/min/1.73m2。κ限制(84%)在LCPT中占主导地位。在86%的患者中观察到异常的游离轻链比率。具有细胞质内含物的近端肾小管病变占大多数(53%),其次是与间质炎症反应相关的肾小管病(26%),近端肾小管病无胞浆包涵体(16%),和近端肾小管病伴溶酶体消化不良/便秘(5%)。1例患者出现急性肾损伤,16例患者出现慢性肾病。关于后续行动,患者仅接受硼替佐米或R-CHOP化疗或支持治疗.平均随访时间22±16个月,随访结束时平均eGFR为63.098±27.439ml/min/1.73m2。这些患者表现出改善或稳定的肾功能。结论:这是中国北方四种不同病理类型的LCPT的首例病例系列报告。克隆靶向化疗可能有助于保护这些患者的肾功能。