Author: Claude (AI), from PubMed abstracts · Reviewed by: Dr Mina Abdelmseih · Reviewed: 2026-11-15 · Review due: 2027-11-15

Educational content only. Not personalised medical advice. Clinical decisions remain the responsibility of the treating clinician.

Post-operative endophthalmitis

Postoperative endophthalmitis is a sight-threatening emergency: purulent intraocular inflammation caused by an infective agent introduced during surgery, requiring prompt diagnosis and treatment [S7]. It is rare after cataract surgery, but outcomes are often poor, especially in low-resource settings and with virulent organisms [S1] [S2] [S6].

Key points - The ESCRS 2024 guideline recommends intracameral antibiotics to prevent endophthalmitis [S12]; they reduced its incidence 3.5-fold in pooled evidence summarised in a review [S9]. - Treatment starts with prompt intravitreal antibiotics; most post-cataract pathogens are susceptible to vancomycin and ceftazidime, and sampling can be deferred if it would delay injection [S10]. - In the only RCT (EVS, 420 participants), early vitrectomy did not improve acuity compared with vitreous tap and injection [S7]; newer non-randomised studies suggest a role for early complete vitrectomy [S8]. - Toxic anterior segment syndrome (TASS) is non-infectious, typically starts within 12 to 48 hours, and must be distinguished from infection [S5]. - Contaminated surgical solutions can cause outbreaks; one Pseudomonas outbreak after MSICS had a poor outcome in about 50% of patients [S6].

Evidence last checked: 2026-10-17 (PubMed abstracts).

Red flags

• Pain, reduced vision and increasing inflammation after intraocular surgery: treat as endophthalmitis until proven otherwise [S7].
• Very poor presenting acuity: initial visual acuity and organism virulence are the most important predictors of a poor outcome [S2].
• Several cases from one theatre list or batch: suspect a contaminated solution or instrument; an outbreak was traced to trypan blue [S6].
• Previous vitrectomy: a major risk factor in several Asian studies [S2].

Recognise it

• Incidence. 0.06% (140/233,115) after cataract surgery in Chinese reports 1995 to 2009 [S1]; incidence in Asian populations is generally consistent with Caucasian data [S2].
• Organisms. Coagulase-negative staphylococci were most frequent in most Asian studies, but Pseudomonas aeruginosa and Nocardia predominated in some [S2]. In China, 60.1% of samples were culture positive: 87.3% bacterial, 12.7% fungal [S1].
• Presentation. In the Chinese series, 75.3% of eyes presented with acuity worse than 5/200 [S1].
• TASS vs infection. TASS shows prominent limbus-to-limbus corneal oedema and anterior chamber inflammation, usually within 12 to 48 hours of surgery; most patients do well with prompt diagnosis and treatment [S5]. Distinguishing sterile from infectious inflammation remains a recognised area of uncertainty [S11].

Confirm it

• Vitreous cultures have a better diagnostic yield than aqueous cultures [S10].
• Culture results help prognosis but rarely change management; eyes managed without cultures had similar outcomes in the studies reviewed [S10].
• Microbiological yield is limited and molecular techniques have uncertain clinical interpretation [S11].

Manage it

Before acting on this section, check the national and local guidelines, product information and regulatory approvals that apply where you practise. See the medical disclaimer.

Tier A (primary care / no specialist)

• Any patient with pain, redness or falling vision in the weeks after eye surgery needs same-day transfer to an eye surgeon able to give intravitreal antibiotics [G1]. Do not delay transfer for tests.

Tier B (general eye clinic)

1. Give intravitreal antibiotics promptly. Empiric antibiotics are given before microbiology results; vancomycin and ceftazidime cover the large majority of post-cataract pathogens [S10]. Doses are not given in these abstracts: follow your national or local protocol.
2. Take a sample if it does not delay treatment. Vitreous sampling is preferred to aqueous [S10].
3. Prevention. Use intracameral antibiotics [S12]. Moxifloxacin and cefuroxime are the most common choices; 500 μg intracameral moxifloxacin (as reported in [S9]) was cost-effective, including after posterior capsule rupture [S9]. One analysis estimated 2500 patients treated to prevent one case [S9]. Topical antibiotics added no prophylactic benefit to intracameral regimens [S9].
4. Prepare intracameral drugs carefully. Adverse events are rare and mostly due to preparation errors [S9]; compounding or dilution errors with cefuroxime cause ocular toxicity [S4]. Cefuroxime can be given safely to penicillin-allergic patients (level 2a evidence) [S4].

Tier C (specialist centre)

• Vitrectomy. The EVS found no significant difference in acuity between vitrectomy and tap at three months; 41% of all participants reached 20/40 or better (very low-certainty evidence, a single trial published 27 years before the Cochrane review) [S7]. Recent, less rigorous studies propose early complete vitrectomy regardless of presenting acuity; treat this with caution [S8].
• Outbreak investigation. Culture patient and environmental samples; genomic typing linked a multidrug-resistant Pseudomonas outbreak to contaminated trypan blue, susceptible only to imipenem [S6].
• Unresolved issues. Adjunctive corticosteroids, fungal and culture-negative disease, and rising antimicrobial resistance remain areas of uncertainty [S11].

Refer when

Pitfalls

• Waiting for culture results before injecting antibiotics [S10].
• Labelling infection as TASS, or TASS as infection, without close review [S5] [S11].
• Dilution errors when preparing intracameral cefuroxime [S4].
• Relying on topical antibiotics instead of intracameral prophylaxis [S9].
• Assuming coagulase-negative staphylococci everywhere; Pseudomonas and Nocardia predominate in some regions [S2].

Evidence notes

• The triage sheet contained no RCT of intracameral antibiotics; efficacy figures come from reviews [S9] and a guideline [S12]. The ESCRS study is referred to as level 1 evidence that has not been adopted universally [S3].
• Vitrectomy evidence conflicts: the only RCT is old [S7], and newer supporting studies are less rigorous [S8].
• Endophthalmitis incidence fell after 2007 as intracameral use grew; nearly all drugs used gave comparable protection [S3].
• Not covered by these sources: intravitreal antibiotic doses, systemic antibiotics, post-injection and post-traumatic endophthalmitis, and povidone-iodine regimens.

Related articles

• Complications of cataract surgery
• Safety of intravitreal drugs: inflammation, vasculitis and endophthalmitis
• Open-globe injury

References

See the numbered source list below. Each marker [S#] links to its PubMed and DOI record.