Exaggerated arthropod reaction usually manifests as a smooth, red, papular lesion without bubble formation from a central pore.
Ruptured epidermal cyst would be considered if there was a known preexisting cyst that recently changed. No bubble formation would be observed from the central pore.
Extraction is the treatment of choice
Treatment of furuncular myiasis involves removing the larvae or forcing them out of the lesion. Wounds can be covered with a substance, such as petrolatum, nail polish, beeswax, paraffin, or mineral oil, to block respiration.3 Occlusion may be needed for 24 hours to create adequate localized hypoxia to force the larvae to migrate from the wound and allow for easier manual extraction. Surgical removal of the larvae is also effective. A cruciate incision can be made adjacent to the central pore to avoid damaging the organisms.3 A topical, broad-based antiparasitic, such as a 10% ivermectin solution, has also been successfully used to treat furuncular myiasis. This approach works by either inducing larval migration outward or simply killing the larvae.3
Our patient recovered well after we performed a punch biopsy to make a larger wound opening and remove the intact larvae.
ACKNOWLEDGMENT
We thank Richard Pollack, PhD, at IdentifyUS, LLC, for providing the botfly larvae photo.