The difficulties attendant upon the differential diagnosis of sprue and pernicious anemia are well known to those called upon to treat the two conditions. In some cases it is impossible to distinguish between them and this has led some clinicians to regard them as the same disease. Christian (1) has suggested that they are one and the same disease and that sprue may develop into pernicious anemia. Wood (2) has added support to this idea by finding Monilia psilosis in cases of pernicious anemia, which yeasts are regarded by Ashford as the causative organism of sprue. Baumgartner (3) disagrees and thinks that they are two distinct diseases but states that some cases “probably cannot be correctly diagnosed, at least by methods now available.” This disagreement has been under discussion in the literature for years; the diagnosis of the two conditions meanwhile becomes constantly more complex.