What are the common causes of sore eyes in a 1-year-old child?

Common Causes of Sore Eyes in a 1-Year-Old Child

The most common causes of sore eyes in a 1-year-old include infectious conjunctivitis (bacterial, viral, chlamydial), nasolacrimal duct obstruction with secondary dacryocystitis, allergic conjunctivitis, corneal foreign body or abrasion, and less commonly, serious vision-threatening conditions like congenital glaucoma or preseptal/orbital cellulitis. 1, 2, 3

Infectious Causes (Most Common)

Bacterial Conjunctivitis

• Presents with mucopurulent discharge, eyelid swelling, and conjunctival injection 1, 2
• In infants, any purulent conjunctivitis is an emergency until gonococcal causes are ruled out, as gonococcal infection can cause corneal perforation within 24-48 hours, septicemia, meningitis, and death 2
• Gonococcal conjunctivitis manifests 1-7 days after birth with severe, rapidly reaccumulating purulent discharge and marked eyelid swelling, requiring immediate systemic antibiotics 2, 4
• Chlamydial conjunctivitis appears 5-19 days after birth, presents with follicular conjunctivitis, and requires systemic (not just topical) antibiotics 2, 4
• Standard bacterial conjunctivitis remains infectious until 24-48 hours after starting appropriate antibiotic treatment 4

Viral Conjunctivitis

• The presence of eyelid vesicles is pathognomonic for herpes simplex virus conjunctivitis and requires immediate ophthalmology referral, as it can progress to keratitis, corneal scarring, perforation, uveitis, and retinitis 2
• Viral conjunctivitis typically presents with watery discharge and is highly contagious through eye-hand contact and contaminated droplets 5

Nasolacrimal Duct Obstruction and Dacryocystitis

• Nasolacrimal duct obstruction is the most common cause of persistent tearing in children under 1 year 3
• When complicated by infection (acute dacryocystitis), presents with erythema, swelling, warmth, and tenderness over the lacrimal sac 3
• Acute dacryocystitis must be identified and treated early to prevent periorbital cellulitis, orbital cellulitis, meningitis, brain abscess, and sepsis 3
• Dacryocystoceles (swelling with bluish discoloration over the nasolacrimal sac) require urgent ophthalmology referral due to high risk of complications 3

Allergic Causes

Allergic Conjunctivitis

• Occurs in 6% to 40% of the general population and can present in young children 5
• Typically presents with itching, watery discharge, and bilateral involvement 5
• Higher socioeconomic position or type 1 diabetes may increase risk of developing allergies 5

Traumatic Causes

Corneal Abrasion or Foreign Body

• Common presentation in young children who may rub their eyes 6, 7
• Fluorescein staining is mandatory to detect corneal involvement 2
• Requires careful examination as children may have difficulty communicating visual symptoms 7, 8

Serious Vision-Threatening Conditions

Preseptal and Orbital Cellulitis

• Preseptal cellulitis presents with eyelid swelling, erythema, and warmth without proptosis or impaired extraocular muscle function 2
• If accompanied by proptosis or impaired extraocular muscle function, obtain contrast-enhanced CT scan immediately to rule out orbital cellulitis, subperiosteal abscess, or orbital abscess 2

Congenital Glaucoma

• Prevalence of 0.0015%-0.0054% in newborns 5
• Presents with tearing, photophobia, and corneal clouding 5
• Requires urgent ophthalmology referral 5

Red Flags Requiring Immediate Ophthalmology Referral

Refer immediately to ophthalmology if any of the following are present: 5, 1

• Visual loss or changes in visual behavior 1
• Moderate or severe pain causing significant distress 1
• Severe purulent discharge that rapidly reaccumulates after cleaning 1, 2
• Corneal involvement (infiltrates, ulceration, opacity) detected on fluorescein examination 1, 2
• Conjunctival scarring 1
• Lack of response to therapy after 3-4 days of appropriate antibiotic treatment 1
• Recurrent episodes 1
• History of immunocompromise 1
• Eyelid vesicles (pathognomonic for HSV) 2
• Proptosis or impaired extraocular muscle function 2

Critical Pitfalls to Avoid

• Delaying referral for severe purulent discharge in infants can lead to gonococcal conjunctivitis with corneal perforation and systemic complications 2
• Missing corneal involvement by failing to perform fluorescein staining can result in vision-threatening complications 2
• Treating chlamydial conjunctivitis with topical antibiotics alone is inadequate; systemic treatment is required 2, 4
• Dismissing eye pain in preschool children as functional without proper examination may miss serious underlying conditions, though functional eye pain is diagnosed in 91% of cases without obvious cause 8
• Missing signs of dacryocystitis or dacryocystocele can lead to serious complications including meningitis and sepsis 3