Technetium-99m dextran: a promising new protein-losing enteropathy imaging agent.

The purpose of this study was to evaluate technetium-99m dextran (99mTc-Dx; molecular weight 81000) as a prospective protein-losing enteropathy (PLE) imaging agent. Twenty-two patients with diseases commonly associated with PLE and 12 healthy control subjects underwent intravenous 99mTc-Dx scintigraphy. All of the 22 test patients showed significant radiotracer accumulation in the intestines within 3-4 h post injection. The focal, regional or generalised nature of the enteropathy and involvement of the large or small intestine could be identified in most cases. Four of the 12 apparently healthy subjects also showed minimal accumulation in the abdominal area occurring late in the study period. This could have been physiological, related to food habits or due to unsuspected intestinal worms. We attribute the high sensitivity of 99mTc-Dx to its relatively fast blood (background) clearance. The radiotracer may have several other advantages over 99mTc-labelled human serum albumin in imaging PLE.