An association between subcortical dementia and pernicious anemia--a psychiatric mask.

A case report from our psychiatric ward demonstrates the emergence of two different organic pathologies, a subcortical dementia and a pernicious anemia, preceded by a psychiatric presentation mimicking a dementia of depression. We emphasize that the psychiatric mask and the lack of other clinical and paraclinical cobalamin deficiency signs were the chief obstacles to early diagnosis. Only a complete and thorough assessment allowed the real diagnosis. We describe a subcortical dementia, and after a review of the literature, we support the causalty of B12 hypovitaminosis (pernicious anemia) in the genesis of this dementia, in the absence of other organic causes of mental syndromes and in the presence of a positive and well-maintained response to vitamin B12 administration.