Ferric ammonium citrate as a positive bowel contrast agent for MR imaging of the upper abdomen. Safety and diagnostic efficacy.
OBJECTIVE
To evaluate the safety and diagnostic efficacy of two different doses of ferric ammonium citrate as a paramagnetic oral contrast agent for MR imaging of the upper abdomen.


METHODS
Ninety-nine adult patients referred for MR imaging for a known or suspected upper abdominal pathology were included in this randomized multicenter double-blind clinical trial. Imaging was performed with spin-echo (T1- and T2-weighted) and gradient-echo (T1-weighted) techniques before and after administration of either 1200 mg or 2400 mg of ferric ammonium citrate dissolved in 600 ml of water. Safety analysis included monitoring of vital signs, assessment of adverse events, and laboratory testing. Efficacy with regard to organ distension, contrast distribution, bowel enhancement and delineation of adjacent structures was graded qualitatively.


RESULTS
No serious adverse events were reported for either of the two concentrations. A total of 31 minor side effects were noted, of which significantly more occurred in the higher dose group (p<0.01). The diagnostic confidence in defining or excluding disease was graded as better after contrast administration for 48% of all images. Marked or moderate enhancement of the upper gastrointestinal tract was achieved at both doses in 69.5% of cases with no evident difference between the two doses. The higher dose tended to show better results in terms of the contrast assessment parameters.


CONCLUSIONS
Ferric ammonium citrate is a safe and effective oral contrast agent for MR imaging of the upper abdomen at two different dose levels. The higher dose showed a tendency toward better imaging results while the lower dose caused significantly fewer side effects. Therefore the 1200 mg dose can be recommended in view of the risk-to-benefit ratio.
Kivelitz
D
D
Institut für Radiologie, Universitätsklinikum Charité, Berlin, Germany.
Gehl
H B
HB
Heuck
A
A
Krahe
T
T
Taupitz
M
M
Lodemann
K P
KP
Hamm
B
B
D000005:Abdomen; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D003287:Contrast Media; D004064:Digestive System / Q000473:pathology*; D004311:Double-Blind Method; D005260:Female; D005290:Ferric Compounds / Q000008:administration & dosage; D005767:Gastrointestinal Diseases / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D000644:Quaternary Ammonium Compounds / Q000008:administration & dosage; D015203:Reproducibility of Results; D012449:Safety
D003287:Contrast Media; D005290:Ferric Compounds; D000644:Quaternary Ammonium Compounds; C013531:ferric ammonium citrate