What could be causing a male patient's left eye pain when keeping the eye closed, without redness, discharge, or itching, for 2 days?

Eye Pain on Closure Without Redness: Differential Diagnosis and Management

This patient's presentation of unilateral eye pain specifically triggered by eye closure, without redness, discharge, or itching, most likely represents a non-inflammatory ocular surface disorder, referred pain from periocular structures, or early intermittent angle closure—requiring systematic evaluation to exclude vision-threatening conditions before attributing symptoms to benign causes. 1, 2

Immediate Assessment Priorities

Critical Red Flags to Exclude First

• Measure visual acuity immediately to determine if this represents a vision-threatening condition requiring urgent ophthalmology referral 3
• Check intraocular pressure (IOP) to exclude intermittent angle closure glaucoma, which can present with pain in a quiet eye and is a vision-threatening emergency 1, 2
• Assess pupil size and reactivity as mid-dilated or poorly reactive pupils suggest angle closure 4
• Perform careful slit-lamp examination if available, as pain without redness can still represent serious pathology 3, 2

Key Historical Features to Elicit

• Ask about episodes of blurred vision, halos around lights, or previous similar episodes, which suggest intermittent angle closure 4
• Determine if the patient is hyperopic (farsighted), as hyperopic eyes have narrower anterior chamber angles and increased risk of angle closure 4
• Inquire about medications including sulfonamides, topiramate, anticholinergics, or adrenergic agents that can precipitate angle closure 4
• Ask about systemic symptoms including fatigue, dry mouth, or joint pain, as Sjögren's syndrome can cause ocular pain and affects women 20:1 over men 5

Most Likely Diagnostic Considerations

Ocular Surface Disorders Without Inflammation

• Recurrent corneal erosion can cause pain specifically with eye closure or upon awakening, without visible redness, and may follow minor trauma or occur spontaneously 1, 3
• Dry eye disease with corneal epitheliopathy can cause pain on lid closure without obvious external signs, particularly if the patient has risk factors like prolonged screen time or environmental exposures 5
• Superior limbic keratoconjunctivitis (SLK) may present with pain and foreign body sensation, though typically shows some conjunctival injection on careful examination 4

Intermittent Angle Closure

• Early or intermittent angle closure glaucoma can present with pain in a quiet eye between acute episodes, and represents a vision-threatening emergency requiring immediate ophthalmology referral 4, 1, 2
• This diagnosis is more likely if the patient is hyperopic, older, or has a family history of angle closure 4

Referred Pain Syndromes

• Trigeminal neuralgia, sinus disease, or other neurologic conditions can manifest as eye pain without ocular findings 1, 2
• Giant cell arteritis must be considered in patients over 50 years old, as it requires urgent corticosteroid treatment to prevent vision loss 1

Diagnostic Approach Algorithm

Step 1: Urgent Ophthalmology Referral Indicated If:

• Any decrease in visual acuity 6, 3
• Elevated IOP or shallow anterior chamber 4, 1
• Mid-dilated or poorly reactive pupil 4
• Corneal epithelial defect on fluorescein staining 4, 3
• Patient age >50 with new-onset pain and systemic symptoms (to exclude giant cell arteritis) 1

Step 2: If No Red Flags Present, Consider:

• Trial of preservative-free artificial tears for suspected dry eye or mild epitheliopathy 5
• Evaluate for underlying Sjögren's syndrome if patient is female with rapid onset symptoms, by ordering anti-SSA/Ro, anti-SSB/La, rheumatoid factor, and ANA 5
• Consider recurrent corneal erosion if pain is worse upon awakening or with eye opening/closing, and refer to ophthalmology for definitive diagnosis and treatment 1, 3

Step 3: Arrange Follow-up

• Re-evaluate within 24-48 hours if symptoms persist or worsen 3
• Immediate ophthalmology referral if any new symptoms develop including redness, photophobia, vision changes, or increased pain 6, 3

Critical Pitfalls to Avoid

• Never assume "no redness" means "not serious"—intermittent angle closure, optic neuritis, and early uveitis can present with pain in a quiet eye 1, 2
• Do not prescribe topical corticosteroids empirically without proper examination, as they can worsen infectious conditions and mask serious pathology 6
• Avoid dismissing unilateral symptoms as they are more likely to represent structural ocular pathology than bilateral presentations 1, 3
• Do not delay referral if IOP measurement or gonioscopy is unavailable in your setting, as intermittent angle closure requires specialist evaluation 4, 2

Specific Management Based on Most Likely Diagnosis

If Recurrent Corneal Erosion Suspected:

• Ophthalmology referral for confirmation and consideration of treatments including hypertonic saline, bandage contact lens, or anterior stromal puncture 4, 3

If Dry Eye/Sjögren's Suspected:

• Initiate preservative-free artificial tears and environmental modifications 5
• Order serological testing (anti-SSA/Ro, anti-SSB/La, RF, ANA) 5
• Co-manage with rheumatology if Sjögren's confirmed, due to systemic complications including lymphoma risk 5

If Angle Closure Cannot Be Excluded:

• Urgent same-day ophthalmology referral for gonioscopy and IOP measurement 4, 1, 2

Given the 2-day duration without progression to obvious inflammation, this likely represents a non-emergent condition, but the absence of external signs does not exclude serious pathology—proceed systematically through the evaluation algorithm above, maintaining a low threshold for ophthalmology referral. 1, 3, 2