Abstract：
Neuropathy is a frequent complication of Waldenström\'s macroglobulinemia (WM), the most common being a demyelinating polyneuropathy with anti-myelin associated glycoprotein (MAG) antibodies, but also cryoglobulins, vasculitis, neurolymphomatosis, and amyloidosis. We describe a patient with IgM/kappa WM who presented with a severe, not length-dependent, peripheral neuropathy as clinical onset of IgM/kappa-related amyloidosis.
A 69-year-old woman came to our attention for weight loss, gait imbalance and sensory loss at upper limbs. In her medical history, she was in hematological follow-up for WM, and had undergone left carpal tunnel release. At neurological evaluation she had weakness and loss of sensation at upper limbs up to the elbows, more at the left side, gait was unsteady with right foot drop. Hypotrophy and areflexia were present at four limbs. Sensory loss and vibration sense were dramatically reduced. She underwent extensive diagnostic workup.
Laboratory workup revealed an IgM/kappa monoclonal paraprotein of 16 g/L and increased NT-proBNP; anti-MAG antibodies were absent. Bone marrow biopsy demonstrated a population of neoplastic B-lymphocytes. Total-body CT scan and echocardiogram were negative. Neurophysiology revealed a symmetric, no length dependent sensory-motor polyneuropathy Periumbilical fat biopsy was positive for amyloid. Sural nerve biopsy detected amyloid in the wall of an epineurial vein.
This case report describes a rare and unusual manifestation of IgM-related AL amyloidosis in WM. The patient presented with a subacute clinically asymmetric neuropathy with no pain or dysautonomic features as clinical onset of IgM/kappa-related amyloidosis. Sural nerve biopsy was crucial for the diagnosis.
A 69-year-old woman came to our attention for weight loss, gait imbalance and sensory loss at upper limbs. In her medical history, she was in hematological follow-up for WM, and had undergone left carpal tunnel release. At neurological evaluation she had weakness and loss of sensation at upper limbs up to the elbows, more at the left side, gait was unsteady with right foot drop. Hypotrophy and areflexia were present at four limbs. Sensory loss and vibration sense were dramatically reduced. She underwent extensive diagnostic workup.
Laboratory workup revealed an IgM/kappa monoclonal paraprotein of 16 g/L and increased NT-proBNP; anti-MAG antibodies were absent. Bone marrow biopsy demonstrated a population of neoplastic B-lymphocytes. Total-body CT scan and echocardiogram were negative. Neurophysiology revealed a symmetric, no length dependent sensory-motor polyneuropathy Periumbilical fat biopsy was positive for amyloid. Sural nerve biopsy detected amyloid in the wall of an epineurial vein.
This case report describes a rare and unusual manifestation of IgM-related AL amyloidosis in WM. The patient presented with a subacute clinically asymmetric neuropathy with no pain or dysautonomic features as clinical onset of IgM/kappa-related amyloidosis. Sural nerve biopsy was crucial for the diagnosis.
摘要：
目的：神经病是Waldenström巨球蛋白血症（WM）的常见并发症，最常见的是带有抗髓鞘相关糖蛋白（MAG）抗体的脱髓鞘性多发性神经病，还有冷球蛋白，血管炎,神经淋巴瘤病，淀粉样变性.我们描述了一名IgM/κWM患者，不依赖于长度，作为IgM/κ相关淀粉样变的临床发作的周围神经病变。
方法：一位69岁的女性因减肥引起了我们的注意，步态失衡和上肢感觉丧失。在她的病史中,她正在接受WM的血液学随访，并经历了左腕管释放。在神经学评估中，她的上肢一直到肘部都有虚弱和感觉丧失，更多的在左边,步态不稳定，右脚下垂。四肢存在肥大和反射不足。感觉损失和振动感显著减少。她接受了广泛的诊断检查。
结果：实验室检查显示IgM/κ单克隆副蛋白为16g/L，NT-proBNP升高；缺乏抗MAG抗体。骨髓活检显示肿瘤B淋巴细胞群。全身CT扫描和超声心动图均为阴性。神经生理学揭示了一种对称的，无长度依赖性感觉运动多发性神经病脐周脂肪活检显示淀粉样蛋白阳性.腓肠神经活检在神经外膜静脉壁中检测到淀粉样蛋白。
结论：该病例报告描述了WM中IgM相关的AL淀粉样变性的一种罕见和不寻常的表现。该患者表现为亚急性临床不对称神经病，无疼痛或自主神经功能异常，为IgM/κ相关淀粉样变性的临床发作。腓肠神经活检对诊断至关重要。本文受版权保护。保留所有权利。
方法：一位69岁的女性因减肥引起了我们的注意，
结果：实验室检查显示IgM/κ单克隆副蛋白为16g/L，NT-proBNP升高；缺乏抗MAG抗体。
结论：该病例报告描述了WM中IgM相关的AL淀粉样变性的一种罕见和不寻常的表现。
