Additional conjunctival and penile pigmentation in Laugier–Hunziker syndrome: a report of two cases

Background  Laugier–Hunziker syndrome is a rare acquired hyperpigmentation of the oral mucosa and lips which is often associated with longitudinal melanonychia. We report two patients exhibiting the classical features of Laugier–Hunziker syndrome with additional and previously unreported conjunctival and penile pigmentation. Patients and methods  Two patients presented with a history of progressive acquired macular pigmentation of the oral mucosa, the lips, the ocular conjunctiva and the penis. Longitudinal melanonychia was found in one patient. Microscopic features (basal epithelial melanosis, moderate acanthosis and superficial pigmentary incontinence) and ultrastructural details (increased number of normal-appearing melanosomes inside basal keratinocytes and dermal melanophages) were characteristic of Laugier–Hunziker syndrome. Conclusions  These two observations illustrate the topographical variations of Laugier–Hunziker syndrome and highlight the need to expand the originally described features to include more widespread areas of hyperpigmentation.