Histopathological features of tungiasis in Peru.

Tungiasis is an ectoparasitic skin disease caused by Tunga penetrans and Tunga trimamillata. There is a lack of histopathological studies that evaluate the recognition of this flea in tissues. We describe the ex vivo dermoscopic and the histopathological patterns of six cases and relate the findings to the developmental stage of the parasite as defined by the Fortaleza classification: two were classified as Fortaleza 3b, 3 as 4a, and 1 as 4b. Two dermoscopic patterns were observed: a brown pigmented ring and a radial crown with a central pore. The most common histopathological findings were an eosinophilic cuticle, eggs in different stages of development, tracheal rings (parasite), and basal hyperplasia (host). The eosinophilic cuticle, eggs in different stages of evolution, and tracheal rings can help to establish the diagnosis when other parts of the parasite are lacking. The Fortaleza staging may represent a tool for pathology reporting purposes.