Renal Division, Department of Medicine, Peking University First Hospital; Institute of Nephrology, Peking University; Renal Pathology Center, Institute of Nephrology, Peking University; Key Laboratory of Renal Disease, Ministry of Health of China; Key Laboratory of CKD Prevention and Treatment, Ministry of Education of China; Ministry of Education of China; Research Units of Diagnosis and Treatment of Immune-mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, 100034, People's Republic of China.
Laboratory of Electron Microscopy, Pathological Centre, Peking University First Hospital, Beijing, 100034, People's Republic of China.
J Nephrol. 2021 Aug;34(4):1169-1177. doi: 10.1007/s40620-020-00926-7. Epub 2021 Jan 4.
Light chain cast nephropathy is the most common form of renal lesion in multiple myeloma. Kidney impairment caused by light chain cast nephropathy can be reversed and survival can be improved if early diagnosis is available. It is thus of imperative importance to develop a non-invasive method to diagnose light chain cast nephropathy once the kidney biopsy is not always applicable.
We consecutively screened newly diagnosed multiple myeloma patients with kidney biopsies from 4 centers in China. Kidney pathologies were reviewed and clinical presentations were recorded. Then a diagnostic model was established by logistic regression and the predictive values were assessed.
Between 1 June 1999 and 30 June 2019, a kidney biopsy was performed in 94 patients with newly diagnosed multiple myeloma, and light chain cast nephropathy was the most common pattern, seen in 52% of biopsied patients. The diagnostic model was established by multivariate logistic regression analysis as P(z) = 1/(1 + e) and z = - 0.093 Hemoglobin (g/L) + 0.421 Serum albumin (g/L) + 3.463 Acute kidney injury (0/1) - 9.207 High-density lipoprotein (mmol/L). If P(z) ≥ 0.55, the diagnosis pointed to light chain cast nephropathy; if P(z) < 0.55, the diagnosis favored non-light chain cast nephropathy. The area under the receiver operating characteristic curves was 0.981 (95% CI 0.959, 1.000). The model had a sensitivity of 93.9%, a specificity of 95.6%, a positive predictive value of 96.0%, a negative predictive value of 94.0%, and a total consistency of 95.0%.
We built a novel, non-invasive diagnostic model through a multicenter study, which may be helpful in the diagnosis of light chain cast nephropathy in newly diagnosed multiple myeloma patients.
轻链 casts 肾病是多发性骨髓瘤最常见的肾脏病变类型。如果能早期诊断，轻链 casts 肾病引起的肾脏损害是可以逆转的，生存也可以得到改善。因此，开发一种非侵入性的方法来诊断轻链 casts 肾病至关重要，因为并非总是可以进行肾活检。
我们连续筛查了来自中国 4 家中心的新诊断多发性骨髓瘤患者的肾活检。回顾了肾脏病理，并记录了临床表现。然后通过逻辑回归建立了一个诊断模型，并评估了预测值。
1999 年 6 月 1 日至 2019 年 6 月 30 日，对 94 例新诊断多发性骨髓瘤患者进行了肾活检，其中最常见的病理类型是轻链 casts 肾病，在活检患者中占 52%。多变量逻辑回归分析建立了诊断模型，P(z)=1/(1+e)，z=-0.093 血红蛋白（g/L）+0.421 血清白蛋白（g/L）+3.463 急性肾损伤（0/1）-9.207 高密度脂蛋白（mmol/L）。如果 P(z)≥0.55，则诊断指向轻链 casts 肾病；如果 P(z)<0.55，则诊断更倾向于非轻链 casts 肾病。受试者工作特征曲线下面积为 0.981（95%CI 0.959，1.000）。该模型的灵敏度为 93.9%，特异性为 95.6%，阳性预测值为 96.0%，阴性预测值为 94.0%，总一致性为 95.0%。
我们通过多中心研究建立了一种新的非侵入性诊断模型，可能有助于诊断新诊断多发性骨髓瘤患者的轻链 casts 肾病。
