Painful red eyes in a contact lens wearer

A 21 year old woman from Singapore presented to the eye hospital with a two week history of painful red eyes, where the severity of the pain was continuing to worsen. She was short-sighted and wore rigid gas permeable contact lenses on most days and admitted to sometimes sleeping with them in situ. She had last worn contact lenses a week before presentation. She reported that she had been cleaning the lenses with tap water over the past two months, including during a holiday in Thailand. She had not been unwell recently, in close proximity to anyone with conjunctivitis, or been subject to trauma. No previous ophthalmic or medical history was noted.

On examination, the best corrected visual acuity was 6/36 right eye and 6/9 left eye, tested with glasses. The conjunctival vessels were diffusely injected. The corneas stained bilaterally in a punctate fashion with fluorescein over a patchy area of whitish haze within the centre and mid peripheries (fig 1⇓).