Carpal Tunnel Syndrome: A Potential Early, Red-Flag Sign of Amyloidosis.

Carpal tunnel syndrome (CTS) can be caused by the deposition and accumulation of misfolded proteins called amyloid and is often an early manifestation of systemic amyloidosis. In patients undergoing surgery for idiopathic CTS, a recent study identified amyloidosis by tenosynovial biopsy in 10.2% of men older than 50 years and women older than 60 years; all positive patients had bilateral symptoms. These findings have led to a renewed interest in amyloidosis as an etiology of CTS. The 2 most common systemic amyloidoses, immunoglobulin light chain and transthyretin amyloidosis, affect the heart, nerves, and other organ systems throughout the body including the soft tissues. Patients with cardiac involvement of amyloidosis have an especially poor prognosis if the disease remains unrecognized and untreated. Early diagnosis is paramount, and patients classically present with cardiac disease several years after being operated on by a hand surgeon for carpal tunnel release. Herein, we present a review of amyloidosis as it pertains to CTS and an algorithm for the detection of amyloidosis in patients undergoing carpal tunnel release. Implementation of this straightforward algorithm will allow for early diagnosis of amyloidosis, a group of progressive and lethal diseases.