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WhatsTheDx publishes a new Optometry case every day. Five clues, one diagnosis, and no account needed to play.
Play today's Optometry caseFive progressive clues
These are the case findings in their original reveal order, moving from the broader presentation to the most discriminating evidence.
Clue 1
A 52-year-old woman takes an urgent slot for a left eye that has been red for nine days. She has worked through two different bottles of drops from the pharmacy and neither has made the slightest difference, which is mostly why she has finally come in.
Clue 2
The redness sits in one sector rather than across the whole white of the eye, and it looks as though it is coming from underneath rather than sitting on the surface. There is no discharge and no stickiness in the morning. Vision is unchanged at 20/20 in each eye. She has had rheumatoid arthritis for six years and takes methotrexate.
Clue 3
Pressed on what the pain is actually like, she says it is severe, and boring rather than scratchy — nothing like having something in the eye. It is worse at night and has woken her in the early hours for four nights running. It radiates into her brow and jaw, it hurts more when she moves the eye, and the globe is tender when pressed gently through the closed lid.
Clue 4
Taken over to the window and looked at in daylight rather than under the slit lamp, the involved sector carries a blue-violet hue from the vessels in the deeper plane. There is no thinning of the white of the eye, no avascular patch and no necrosis. Intraocular pressure is 15 mmHg right and 16 mmHg left.
Diagnosis
Scleritis
Why the diagnosis fits
Two features carry this case, and both are about depth. The first is the pain. A red eye that itches, scratches or feels gritty is a surface problem; this pain is severe and boring, it wakes her in the early hours, it radiates into the brow and jaw, it is worse on eye movement, and the globe is tender through the closed lid. That is not a surface complaint, and it is the single most useful thing she says. The second is the phenylephrine drop. Phenylephrine constricts the superficial vessels. If the inflamed vessels were in the layer above the white of the eye, the eye would go quiet and white within minutes. Hers does not blanch at all, which places the engorged vessels below the reach of the drop — in the wall of the eye itself. The blue-violet hue seen in daylight rather than under the slit lamp says the same thing in colour: it is the deep vascular plexus showing through. The rest of the picture fits and adds context. Half of patients with this condition have an underlying autoimmune disease, with rheumatoid arthritis and the vasculitides commonest, and she has had rheumatoid arthritis for six years. Peak incidence runs from 47 to 60 with a 60% to 74% female predominance, and she is 52. Two negatives matter as much as the positives: there is no scleral thinning, avascular patch or necrosis, and the dilated examination is clean, so this is the mild-to-moderate anterior form rather than the necrotising or posterior variants that carry the real risk of visual loss. Her acuity is untouched at 20/20. One practical trap is worth naming. She has already failed two bottles of drops, and it would be easy to read that as evidence against inflammation. It is not: topical steroids have very limited success here, so failing topical treatment is expected rather than informative. The treatment is systemic — oral NSAIDs first-line, indomethacin 50 mg three times daily being a standard regimen, with systemic corticosteroids and immunosuppressives reserved for inadequate response. And because half of these patients have systemic disease, the eye finding is also a prompt to ask how well the rheumatoid disease is actually controlled.
Educational reference
The explanation and decisive case findings were checked against the source below.
Open the clinical referenceEditorial policy and correctionsFor education and entertainment only. This fictional case is not medical advice and does not replace supervised clinical training, diagnosis, or treatment.
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