Case Report|Articles in Press

A Nonsurgical Approach to Management of Lepidopterism due to Woolly Bear Caterpillar Ingestion

Published:March 01, 2023DOI:
      Systemic symptoms resulting from exposure to members of the Lepidoptera order, such as moths, butterflies, and caterpillars, are known as lepidopterism. Most cases of lepidopterism are mild and result from dermal exposure to urticating hairs; ingestion is less common and generally more medically significant because the hairs may get embedded in the patient’s mouth, hypopharynx, or esophagus, leading to dysphagia, drooling, edema, and possible airway obstruction. In previous cases of symptomatic caterpillar ingestion reported in the literature, extensive efforts, including direct laryngoscopy, esophagoscopy, and bronchoscopy, were undertaken to remove these hairs. We review the case of a 19-mo-old previously healthy male infant who presented to the emergency department with vomiting and inconsolability after ingesting half of a woolly bear caterpillar (Pyrrharctia isabella). His initial examination was notable for embedded hairs in his lips, oral mucosa, and right tonsillar pillar. The patient underwent a bedside flexible laryngoscopy, which revealed a single hair embedded in the epiglottis, without significant edema. He was stable from a respiratory standpoint and, thus, was admitted for observation and IV dexamethasone without any attempt to remove the hairs. He was discharged in good condition after 48 h; at a follow-up visit 1 wk later, no remaining hairs were visible. This case demonstrates that lepidopterism secondary to caterpillar ingestion is amenable to conservative management and does not require routine removal of urticating hairs in patients who do not show signs of airway distress.


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