Black maculae between the toes: A rare form of Laugier–Hunziker syndrome?

Abstract

Dermoscopy on the dark spot between the third and fourth toes of the left foot exhibited unsymmetrical pigmentation without blue-white veil, which did not show a typical character of melanoma [Figure 2]a. After a detailed examination of the skin, we found black spots on the lip and oral mucosa [Figure 2]b with unknowing disease course, but no abnormity on fingernail, toenails, or genitalia was seen. The patient underwent enteroscopy examination which exhibited that colorectum mucosa had no obvious abnormity [Figure 2]f. Based on the clinical manifestation and the results of the accessory examinations, we diagnosed this case as Laugier–Hunziker syndrome (LHS), which to our knowledge was the first case report of LHS presenting melanotic macules between all the toes. [3],[4] PJS is characterized by mucocutaneous pigmentation and multiple gastrointestinal hamartomatous polyps that belong to autosomal dominant inherited disease due to LKB1/STK11 gene mutation or some other genetic disorders.