What Is Your Diagnosis? Stinkbug Staining

The Diagnosis: Stinkbug Staining

After discussing management options with the patient including biopsy, we decided that we would photograph the lesion and follow-up in clinic. While dressing, the patient discovered the source of the pigment, a stinkbug, stuck to the corresponding area of the sock.

The brown marmorated stinkbug (Halyomorpha halys)(Figure) is a member of the Pentatomidae family. This insect is native to East Asia and has become an invasive species in the United States. Their presence has recently increased in the eastern United States and they have become an important agricultural pest as well as a household nuisance. Stinkbugs most commonly interact with humans during the fall and winter months when they enter homes because of cooler temperatures outdoors. They can fit into many unexpected places because of their thin profile.¹

The brown marmorated stink bug (Halyomorpha halys).

Stinkbugs earned their name because of their defensive release of a malodorous chemical. This chemical is comprised of trans-2-decenal and trans-2-octenal, which are both aldehydes and are chemically related to formaldehyde. Based on the material safety data sheet, trans-2-decenal also may be responsible for the orange-brown color seen on the patient’s skin.² Contact dermatitis caused by direct excretion of this chemical onto human skin has been reported³; anecdotal reports of irritation in agricultural workers have been noted. Stinkbugs are becoming a more common household and agricultural pest and should be recognized as possible causes of some presentations in the dermatology clinic.