Peripheral neuropathy as an early marker of AL amyloidosis.

Fifty-one of 146 patients with primary amyloid deposits of light-chain origin (AL) examined between 1972 and 1986 were found to have peripheral neuropathy as part of their systemic amyloidosis. Peripheral neuropathy was the presenting symptom in 11 patients, and it was a later symptom or an incidental physical examination finding at the time of amyloid workup in 40 additional patients. The median duration of time from first symptom to the diagnosis of primary amyloidosis was longer in those whose first symptom was neuropathy (48 months vs 12 months). In addition, survival time after diagnosis for these patients was significantly longer (at least 35 months vs 16 months). Peripheral neuropathy is not an uncommon symptom of primary amyloidosis and may mark the onset of the disease process years before infiltration of vital structures of the heart, kidneys or gastrointestinal tract leads to failure and a subsequent downhill course. Appreciating amyloid disease at this early stage may widen the potential therapeutic window.