Acquired amyloid peripheral neuropathy

Acquired amyloid peripheral neuropathy is a neurological condition in which abnormal amyloid protein deposits accumulate in peripheral nerves, leading to progressive nerve damage. Unlike hereditary forms of amyloid neuropathy (such as those caused by transthyretin gene mutations), this condition arises in the context of acquired systemic amyloidosis, most commonly AL (immunoglobulin light chain) amyloidosis associated with plasma cell dyscrasias, or less frequently AA amyloidosis related to chronic inflammatory conditions. The amyloid deposits infiltrate and damage peripheral nerve fibers, affecting both sensory and motor function. The condition primarily affects the peripheral nervous system, often presenting as a length-dependent sensorimotor polyneuropathy. Key symptoms include numbness, tingling, burning pain, and loss of sensation in the hands and feet, which may progress proximally over time. Motor weakness can develop as the disease advances. Autonomic nervous system involvement is common and may manifest as orthostatic hypotension, gastrointestinal dysmotility (constipation, diarrhea), erectile dysfunction, and abnormal sweating. Carpal tunnel syndrome is a frequent early manifestation, sometimes preceding other neuropathic symptoms by years. Other organ systems, including the heart, kidneys, and liver, may also be affected depending on the type and extent of systemic amyloid deposition. Treatment is directed at the underlying cause of amyloid production. For AL amyloidosis, chemotherapy regimens targeting the abnormal plasma cell clone (such as bortezomib-based combinations, melphalan, or autologous stem cell transplantation) are the mainstay of therapy. Supportive management of neuropathic symptoms includes pain medications (gabapentin, pregabalin, duloxetine), physical therapy, and treatment of autonomic dysfunction. Early diagnosis and treatment of the underlying amyloidosis are critical, as nerve damage may be partially irreversible once established. Prognosis depends on the extent of systemic organ involvement and response to treatment.

Common questions about Acquired amyloid peripheral neuropathy