Cheryl is a 65-year-old retiree and avid gardener who reports a 24-hour history of redness, discomfort, irritation and tearing affecting the right eye.

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<p>Cheryl is a 65-year-old retiree and avid gardener who reports a 24-hour history of redness, discomfort, irritation and tearing affecting the right eye.</p><p>The symptoms started shortly after an assertive bout of weeding and dealing with a hairy caterpillar infestation of her veggie patch.</p><p>She does not recall any trauma or injury to the eye.</p><p>She wears contact lenses very occasionally, mostly for water sports, which she hasn’t done for some months.</p><p>Cheryl is systemically well, with no history of atopy, and no URTI symptoms. There is no pain on eye movement.</p><p>On examination, vital signs are unremarkable, pupils are equal and reactive. The right conjunctiva appears diffusely red.</p><p>VA is 6/9 corrected bilaterally. Fluorescein staining findings for the right eye are pictured. The left eye examines normally.&nbsp;</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.