Millipede Dermatitis Mimicking Pediatric Snake Envenomation: A Case Report

Millipede dermatitis is an uncommon clinical presentation caused by exposure to defensive secretions released by millipedes, often resulting in striking cutaneous discoloration that may mimic more serious conditions such as envenomation, infection, vasculitis, or tissue necrosis. We present the case of a previously healthy four-year-old male who developed acute black discoloration and mild pain involving the plantar surfaces of the right toes after playing barefoot outdoors. Physical examination demonstrated sharply demarcated black discoloration with surrounding erythema and mild edema while preserving neurovascular function and sparing the interdigital spaces. Initial concern for possible snake envenomation prompted empiric administration of CroFab and clindamycin prior to transfer. Laboratory evaluation, including complete blood count, coagulation studies, fibrinogen, creatine kinase, and metabolic testing, was unremarkable. Further history later revealed exposure to a black-and-yellow millipede, and the discoloration partially improved with alcohol swabbing, confirming exogenous pigmentation rather than tissue necrosis. The patient was managed conservatively with supportive care and experienced complete resolution without complications. This case highlights the importance of recognizing millipede dermatitis as a benign mimic of more serious toxicologic and infectious conditions in pediatric patients. Increased awareness may help avoid unnecessary antivenom administration, invasive interventions, hospital transfers, and healthcare costs.