(111)Indium-transferrin for localization and quantification of gastrointestinal protein loss.
OBJECTIVE
To evaluate the indium-111 ((111)In)-transferrin method as a means of localization and quantification of gastrointestinal protein loss.


METHODS
Fourteen patients and 15 healthy subjects underwent an (111)In-transferrin study consisting of abdominal scintigraphy, whole-body counting measurement and determination of plasma activity of (111)In during the course of 5 days. Two of the patients went through a subsequent chromium-51-trichloride test with analysis of radioactivity in faeces in order to compare the results of the two methods.


RESULTS
The patients had a mean +/-SEM whole-body loss of (111)In of 10.9+/-2.9% for 96 h, while the healthy controls lost 1.8+/-1.3% (p=0.0045). The decay in plasma activity followed biexponential kinetics. The characteristic plasma transit time was 5.0+/-1.0 h in patients and 12.1+/-1.5 h in controls (p=0.0007). Scintigraphically, patients had obvious abdominal foci of activity, while the control subjects showed diffuse activity. Anatomic localization of the leaking spot seemed more uncertain. By comparison with the (51)CrCl(3) test, the loss of radio-labelled protein appeared to be in the same order of magnitude.


CONCLUSIONS
Quantification of gastrointestinal protein loss can be done without collecting faeces. Normal subjects have a loss of a few per cent, making the (111)In-transferrin method comparable with the former standard using (51)CrCl(3). Plasma measurements of (111)In are not predictive of the magnitude of the loss. Scintigraphic localization of the site of the loss needs to be optimized, for instance by serial imaging or image fusion with an anatomical modality.
Simonsen
Jane Angel
JA
Department of Nuclear Medicine, Odense University Hospital, Odense C, Denmark. Jane.Simonsen@ouh.regionsyddanmark.dk
Braad
Poul-Erik
PE
Veje
Annegrete
A
Gerke
Oke
O
Schaffalitzky De Muckadell
Ove B
OB
Høilund-Carlsen
Poul Flemming
PF
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007204:Indium; D007205:Indium Radioisotopes; D008297:Male; D008875:Middle Aged; D011504:Protein-Losing Enteropathies / Q000000981:diagnostic imaging*; D011506:Proteins / Q000032:analysis*; D011877:Radionuclide Imaging; D014168:Transferrin
D007205:Indium Radioisotopes; D011506:Proteins; D014168:Transferrin; D007204:Indium