Luciano Schiazza M.D.
Pigmented papillae of the tongue (PFPT) is a benign condition characterized by well-circumscribed hyperpigmentation confined solely to fungiform papillae. Lesions are generally asymptomatic. PFPT may begin during late infancy but usually occurs in the second and third decade of life with a predilection for females.
Fungiform papillae normally are pink, mushroom shaped projections (as the name implies) with discrete predominance along the ventral-anterior and lateral aspects of the tongue. They rise above the general level of the filiform papillae.
PFPT is generally considered as a common finding in African American individuals, in Australian aborigines and Indians. It is considered rare people with light skin.
The pathogenesis and the reason for the abnormalities being limited to the fungiform papillae remains unknown. It could be considered a benign variant of oral hyperpigmentation seen in high phototypes and would denote an active pigmentation system in an area where it is generally inactive.
The histological features of pigmented fungiform papillae include numerous melanophages in the lamina propria of the papillae with lack of inflammatory infiltrates. The pigment located within the melanophages stains positive for melanin with Fontana-Masson and negative for iron with Prussian blue.
PFPT have been classified into three clinical types:
the first type is a well-circumscribed hyperpigmented area involving all the fungiform papillae on the anterolateral side or towards the tip of the tongue.
the second type shows hyperpigmentation involving 3-7 fungiform papillae scattered on the dorsal surface of the tongue,
the third type hyperpigmentation is seen on every fungiform papilla on the dorsum of the tongue.
Dermoscopy showed projections with pigmented borders, interspersed by dichotomized vessels originated in their base, with aspect resembling ‘‘rose petals”
Differential diagnosis include other causes of pigmentation of the oral mucosa such as hemochromatosis, pernicious anemia, amalgam tattoo, Peutz-Jeghers syndrome, Addison's disease, von Recklinghausen syndrome and melanocytic nevus.
However, a clear diagnosis can be reached in all those disorders on the basis either of the distribution and clinical characteristics of the pigmentation or the accompanying manifestations.