Geographic tongue in two siblings.

We report two illustrative cases of geographic tongue which occurred in 6- and 4-year-old sisters whose father had fissured tongue. The elder sister had mild atopic dermatitis and nail changes, but there was no family history suggestive of psoriasis. Histologically, the geographic tongue in the elder sister showed the same features as the oral lesions in pustular psoriasis. From a review of the literature we suggest that geographic tongue may be classified into two types, one that commonly occurs in atopics and another that develops as an oral manifestation of pustular psoriasis, although both types show similar histopathological features.