The Correct Answer is C!

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A 75 year-old woman with a history of hypertension, hyperlipidemia, and diabetes presents with acute onset of severe right eye pain and blurred vision. On the way to the hospital, she notes that lights looked like they were surrounded by halos. On physical examination, she is in pain and anxious. The right eye is red with a cloudy cornea, and the eye is tender and firm to palpation. The pupil is moderately dilated at 5 mm and unreactive. Visual acuity is decreased in the right eye.

Which of the following is the most likely diagnosis?

  1. Acute bacterial conjunctivitis
  2. Acute anterior uveitis
  3. Acute angle closure glaucoma
  4. Corneal ulcer


The diagnosis here is acute angle closure glaucoma which is the result of closure of a preexisting narrow anterior chamber angle. The features in this case including pain, loss of visual acuity, halo around lights, moderately dilated, nonreactive pupil, and hardness of the eye are all characteristic of acute angle closure glaucoma. The condition is most common in the elderly and can be precipitated by darkness, stress, and use of sympathomimetic or anticholinergic medications. Acute angle closure glaucoma is an ophthalmologic emergency, and without treatment, optic nerve atrophy and vision loss can ensue within hours. Immediate treatment to decrease intraocular pressure is required. Acute anterior uveitis can also present as a painful, red eye, but it is not as likely of a diagnosis here as it more typically presents with a constricted pupil that is sluggishly reactive. Bacterial conjunctivitis also can present as a red eye, but typically, there is obvious discharge, no pain, and no loss of vision or pupil reactivity. Corneal ulcer, most commonly caused by infections, can similarly present as a red, painful eye, with decreased visual acuity; however, discharge is usually present, and pupil size is usually normal and reactive.

1.  Source: "Comparative Analysis of Pre/Post Assessments of Live/Didactic Course Attendees when compared to Mico-Learning/Online Course Users., "Knowledge to Practice, 2017.