Insect and Arachnid Injuries
Bee and wasp stings to the cornea and/or conjunctiva cause conjunctival hyperemia and chemosis acutely, sometimes associated with severe pain, corneal edema, and infiltration, with subsequent decreased vision. The significant variability in the acute response is thought to reflect differences in the quantity of the venom injected and whether the reaction to the venom is primarily toxic or immunologic. In rare instances, other sequelae have been documented, including hyphema, lenticular opacities, anterior uveitis, secondary glaucoma, and heterochromia. Initial therapy with cycloplegics and topical (and occasionally systemic) corticosteroids is beneficial. Removal of externalized stingers may be attempted. After the acute episode, retained stingers may remain inert in the cornea for years. Caterpillar and tarantula hairs (urticating hairs) may also become embedded in the cornea and conjunctiva. These hairs are very fine and usually cannot be removed manually. Because of their structure, these urticating hairs tend to migrate more deeply into ocular tissues and elicit a localized granulomatous inflammatory response (ophthalmia nodosum). In these cases, the patient will have an extreme foreign-body sensation until the hairs migrate below the corneal surface. Inflammatory sequelae usually respond to topical corticosteroids.
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Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.