Schilling test – Stage 1
1. An
oral dose of Co57 labeled vitamin B12 is given
2. Two hours later an intramuscular
injection of unlabeled
vitamin B12 is given
This
is called a “flushing dose”
Purpose
is to saturate storage sites (liver) to eliminate
absorbed labeled B12 from all going to storage
3. A 24 hr. urine collection is
performed and tested for
presence of radioactivity (Co57
labeled
B12)
If
radioactivity detected: >7%
Normal
absorption of B12 takes place
If
no radioactivity detected: <7%
Malabsorption
of B12 need to go to stage 2