What is the incidence of endophthalmitis (inflammation of the interior of the eye) in the pediatric population?

Incidence of Endophthalmitis in Pediatric Population

Pediatric endophthalmitis is rare but devastating, with an overall postoperative incidence of approximately 0.17%, though the incidence varies dramatically by etiology—post-traumatic endophthalmitis occurs in 54% of open globe injuries while post-surgical endophthalmitis ranges from 0.17% to 2-3 per 1,000 procedures depending on the type of surgery.

Overall Incidence by Etiology

The incidence of pediatric endophthalmitis depends critically on the underlying cause:

Post-Traumatic Endophthalmitis

• Ocular trauma represents the most common cause of pediatric endophthalmitis, accounting for 78.3% of all cases 1
• Post-traumatic endophthalmitis develops in 54.16% of pediatric open globe injuries, making it the highest-risk scenario 2
• The risk increases substantially when primary repair is delayed beyond 24 hours, with delayed repair being the only significant independent risk factor in multivariate analysis 2
• Specific injury mechanisms carry different risks: bow and arrow injuries and household kitchen injuries show significantly higher endophthalmitis rates 2

Post-Surgical Endophthalmitis

• The incidence of postoperative endophthalmitis in children is 0.17% over a 7-year period at major tertiary centers 3
• For cataract surgery specifically, the risk without antibiotic prophylaxis is 2-3 per 1,000 procedures (0.2-0.3%) 4
• Post-surgical cases account for 12.6% of all pediatric endophthalmitis cases 1
• Previous glaucoma surgery represents a major long-term risk factor, with 11 of 13 postoperative cases (85%) having at least one prior glaucoma procedure 3
• Time to presentation varies widely from 3 days to 78 months postoperatively, with children ≤3 years old and those with glaucoma procedures showing the longest time-to-onset 5

Endogenous Endophthalmitis

• Endogenous endophthalmitis accounts for 8.4% of pediatric cases 1
• In neonates specifically, 7.3% of all pediatric infective endocarditis cases occur in the first month of life, though this refers to cardiac endocarditis, not endophthalmitis 4
• Endogenous endophthalmitis occurs via hematogenous spread during candidemia or bacteremia, with Candida albicans being the most common causative organism 6
• Risk factors include prolonged hospitalization, indwelling central venous catheters, and immunosuppression 6, 7

Post-Strabismus Surgery Risk

The risk of endophthalmitis following strabismus surgery in both adults and children is exceptionally low at 1 in 30,000 to 1 in 185,000 procedures 4. This represents one of the lowest infection risks among all ophthalmic surgeries.

Age-Specific Considerations

Neonatal Population

• The incidence of neonatal infectious endocarditis has increased over the past 2 decades due to invasive techniques and central venous catheters 4
• Fewer than one-third of neonatal endocarditis cases occur with congenital cardiac disease; most are related to indwelling lines 4
• The mean age at presentation for pediatric endophthalmitis overall is 4.2-5.5 years, though cases range from 8 days to 16 years 3, 5

Older Children

• Children without structural heart disease or identifiable risk factors develop infective endocarditis in approximately 8-10% of pediatric cases, though this refers to cardiac endocarditis 4
• The mean age in one trauma series was 5.3 ± 2.8 years (range 3-10 years) 8

Critical Risk Factors Affecting Incidence

Delayed surgical repair beyond 24 hours is the single most important modifiable risk factor, significantly increasing both the incidence of endophthalmitis and worsening visual outcomes 2. Other key factors include:

• Type of injury: Bow and arrow injuries and household kitchen injuries carry higher risk 2
• Previous glaucoma surgery: Creates long-term elevated risk for postoperative endophthalmitis 3
• Central venous catheters: Major risk factor for endogenous cases 4, 6
• Retained intraocular foreign body: Associated with trauma cases 1

Microbiological Patterns

Culture-positive rates range from 46.2% to 66.7% in pediatric series 5, 8. When organisms are identified:

• Gram-positive bacteria predominate overall, particularly Staphylococcus and Streptococcus species 1, 8
• Streptococcus pneumoniae is the most common identified organism in some series (41.7% of culture-positive cases) 5
• Coagulase-negative staphylococci are common in postoperative cases 4
• Gram-negative organisms and Candida species occur in endogenous cases 4, 6
• Multiple organisms indicate particularly poor prognosis 8

Visual Outcomes and Prognosis

Despite the relatively low incidence, pediatric endophthalmitis carries devastating consequences:

• Only 30.5-42.3% of patients achieve favorable visual acuity (≥20/200) 1, 5
• 20-50% end with no light perception 1, 5
• 12.5-46.2% develop phthisis bulbi (anatomical failure of the eye) 1, 5
• Visual outcomes are significantly worse when primary repair is delayed beyond 24 hours 2