Misleading second-stage Schilling tests due to inactive intrinsic factor concentrate.
D000752:Anemia, Pernicious / Q000175:diagnosis*; D003951:Diagnostic Errors; D004355:Drug Stability; D004356:Drug Storage; D006801:Humans; D007410:Intestinal Diseases / Q000175:diagnosis*; D007437:Intrinsic Factor; D012546:Schilling Test
D007437:Intrinsic Factor