Three patients had pustular psoriasis and one had pityriasis rubra pilaris. They all had identical lesions of the tongue and buccal mucosa, which consist of slightly raised annular, polycyclic, or striate lesions varying in color from gray to yellowish white. The clinical appearance and histopathologic findings of these tongue lesions and those seen in Reiter's syndrome and geographic tongue are identical. "Annulus migrans" is suggested as the most appropriate name for this entity.
O'Keefe E, Braverman IM, Cohen I. Annulus MigransIdentical Lesions in Pustular Psoriasis, Reiter's Syndrome, and Geographic Tongue. Arch Dermatol. 1973;107(2):240-244. doi:10.1001/archderm.1973.01620170052014