Clinical Chemistry, Vol 15, 295-306, Copyright © 1969 by the American Association for Clinical Chemistry

Lipiodol Absorption and Urinary Iodide Excretion as a Screening Test for Steatorrhea

¹ Clinical Chemistry Laboratory, University Health Center of Pittsburgh, and Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pa. 15213.

The Lipiodol absorption test, quantifying urinary iodide concentration 8-12 hr. after ingestion of Lipiodol, is proposed as an effective screening technic for lipid malabsorption. Urinary iodide is converted to free iodine with nitrous acid; the free iodine is extracted into chloroform, producing a characteristic pink color which is quantified photometrically. Under the dosage conditions used, a urinary iodide concentration of less than 0.4 mM/L strongly suggests abnormal absorption of fat. The results of this test have been correlated with fat balance studies in 12 patients with symptoms of intestinal disease and 12 patients asymptomatic for intestinal disease. The screening test was abnormal in all 7 patients with abnormal fat balance studies and in 2 patients with normal fat balance studies. The remaining 15 patients had a normal screening test and normal fat balance studies. No false negatives were found. The simplicity of the test, coupled with its high correlation with the fat balance studies, recommend its use in the clinical laboratory as a valid screening procedure in all patients with suspected steatorrhea.