Distal sensory polyneuropathies are often of diabetic or chronic inflammatory origin. Rarely they may be sporadic manifestations of familial amyloid polyneuropathy (FAP). Its early diagnosis is important, because a therapy is available for transthyretin (TTR)-related FAP.

Case report:

A white male of 65 years has had tingling sensations of hands and feet since two years, weight loss of 15 kg and reduced exercise capacity, further orthostatic syncopes and episodes of diarrhea. 

Neurologically we found distal symmetric hypaesthesia and hypalgesia with atrophies of the small foot and hand muscles, loss of malleolar vibration sense and mild ataxia in Romberg’s test. Tendon reflexes at the lower extremities were absent, there was no manifest paresis.

TTR-FAP is an autosomal dominant amyloidosis, caused by misfolded monomeres of the TTR protein with amyloid deposits at nerve ends and inner organs. The late-onset type is quite common, its clinical features are rapidly progressive polyneuropathy with ataxia, involving also the hands and autonomic functions (Dohrn et al., J. Neurol. 2013). Our case shows that TTR-FAP may also manifest as mild sensory neuropathy without ataxia, but with autonomic symptoms. Causal therapy is liver transplantation, whereas medical treatment with tafamidis may improve or delay symptoms.