Familial amyloidosis with polyneuropathy. Aspects of the relationship between gastrointestinal symptoms, EMG findings, and malabsorption studies.

Fifty-two patients with a confirmed diagnosis of familial amyloidosis with polyneuropathy living in northern Sweden were investigated. Gastrointestinal symptoms, mainly in the form of changed bowel habits, were found in 47 patients. Symptoms of polyneuropathy of the peripheral nerves usually preceded the gastrointestinal symptoms, but in 12 patients gastrointestinal dysfunction started either before or simultaneously with the neurological symptoms. Steatorrhea was found in 30 patients (58%) and an impaired D-xylose absorption in 52%. Diarrhea, anal incontinence, and a high degree of peripheral denervation indicating a severer disease were related to the presence of steatorrhea. The results of oral lactose and glucose tolerance tests were essentially normal. The results suggest that the main reason for the gastrointestinal dysfunction is a disruption of the gut autonomic nervous system rather than a barrier to the absorption of nutrients across the intestinal wall.