Gastrointestinal Protein Loss in Rheumatoid Arthritis, Studied with ⁵¹cr-Chromic Chloride and ¹²⁵i Albumin

Abstract

Patients with rheumatoid arthritis and healthy controls have been studied with respect to the gastrointestinal excretion during 7 days of ⁵¹Cr-activity after the intravenous administration of ⁵¹Cr-CrCl₃ according to a method described by Rootwelt, 1966. Most of the subjects included were simultaneously studied with respect to albumin pools and catabolism by ^l23I-labelled albumin.

1. The control group had a mean cumulative ⁵¹Cr excretion during 7 days of 0.7±0.33 % of the dose.

2. The patients with rheumatoid arthritis had a mean ⁵¹Cr excretion of 1.7±1.0% of the dose, which is significantly higher than the mean control value.

3. The low normal chromium excretion makes it possible to assess even small elevations of the gastrointestinal protein loss.

4. The possibility that the small gastrointestinal protein loss could be a symptom of early amyloid vascular lesion in patients with long-standing rheumatoid arthritis is pointed out.

5. Intravenous injection of ⁵¹Cr-CrCl₃ is a comparatively convenient method for the diagnosis and quantitation of gastrointestinal protein loss.