Dermatology Online Journal

Letter: Tunga Penetrans – Egg head?
Rebecca Dunn MBBS, Ruth Asher MBChB FRCPath, Jonathan Bowling MBChB FRCP
Dermatology Online Journal 16 (10): 14

Churchill Hospital, Oxford, United Kingdom

---

Figure 1
Figure 1. Misleading histopathology with arrows pointing to nucleated cells in the Tunga penetrans flea head, not to eggs as was suggested in the initial manuscript. (H&E, x10)

We appreciate the contribution of your journal to increasing awareness that tungiasis is becoming a more frequent presentation in returned travellers from endemic areas. However, in reference to the paper “Tungiasis in the United States: A travel souvenir” [1] published in December 2008, the histology depicted is misleading. The image is labeled with the green arrows pointing to round structures consistent with eggs but the histology specimen clearly demonstrates the head, substantiated by the presence of eye sockets peripherally and mouth parts centrally. The round structures appear to be nucleated cells (Figure 1). The eggs of Tunga penetrans are ovoid, measure approximately 600 x 320 µm [2] and are clearly visible with naked eye. Eggs are typically confined to the parasite’s abdomen, which is not shown in this section.

The abdomen of an impregnated female Tunga penetrans flea undergoes massive hypertrophy while embedded in the skin of its host. During this time it produces 100-300 eggs, which are released into the environment before it dies and is extruded from the skin by normal repair mechanisms.

The head is a rare finding in biopsy specimens of Tunga penetrans [3] and may be the reason for misinterpretation.

References

1. Hager J Jacobs A Orengo I Rosen T. Tungiasis in The United States: A travel souvenir. Dermatology Online Journal. 2008; 14(12):3 [PubMed]

2. Nagy N et al. Investigations on the life cycle and morphology of Tunga penetrans in Brazil. Parasitol Res. 2007. 101(S2):S233-S242 [PubMed]

3. Smith M. Procop G. Typical histologic features of Tunga penetrans in skin Archives of Pathology and Laboratory Medicine 2002;126(6): 714-7 [PubMed]

© 2010 Dermatology Online Journal