Endophthalmitis: Types, Organisms and Management

Last updated: October 2026

Endophthalmitis is the complication every surgeon fears. Recognising it early, sampling correctly and injecting the right antibiotics on the same day are the skills that save eyes.

Types and typical organisms

Recognise it

• Pain and reduced vision after surgery or injection are endophthalmitis until proven otherwise.
• Signs: lid swelling, conjunctival injection, anterior chamber cells and fibrin, hypopyon, vitritis, and loss of the red reflex.
• Use B-scan ultrasound if the fundus cannot be seen, to assess vitreous opacities and exclude a detachment or retained lens material.

Don't confuse it with TASS

Toxic anterior segment syndrome is a sterile inflammation from something introduced during surgery. Clues: onset within 12–24 hours, diffuse "limbus-to-limbus" corneal oedema, little pain, and a relatively clear vitreous. It responds to intensive topical steroids. When in doubt, treat as infection.

Management

• Same-day sampling: aqueous and vitreous tap (or vitrectomy), sent for Gram stain, culture and, where available, PCR.
• Intravitreal antibiotics (typical doses; follow your unit protocol):
  • Vancomycin 1 mg/0.1 mL (Gram-positive cover)
  • Ceftazidime 2.25 mg/0.1 mL, or amikacin 0.4 mg/0.1 mL (Gram-negative cover)
• Suspected fungal: intravitreal voriconazole (commonly 100 µg/0.1 mL) or amphotericin B (commonly 5 µg/0.1 mL), with systemic antifungals for endogenous disease.
• EVS rule for post-cataract cases: immediate vitrectomy if vision is light perception only; tap-and-inject if hand movements or better.
• Systemic treatment is essential for endogenous endophthalmitis and commonly used after trauma; the EVS found no benefit for systemic antibiotics in post-cataract cases.
• Intravitreal steroids are sometimes added to reduce inflammation, but their benefit is debated.
• Review at least daily. Repeat injections or vitrectomy if the eye worsens.
• Chronic endophthalmitis often needs capsulectomy or IOL removal plus vitrectomy, because the organisms hide in the capsular bag.

Prevention

• Povidone-iodine 5% to the conjunctival sac before surgery and injections has the strongest evidence.
• Drape the lashes away from the field and treat blepharitis before elective surgery.
• Intracameral antibiotic at the end of cataract surgery reduced endophthalmitis about fivefold in the ESCRS study.
• Secure, watertight wounds; avoid vitreous loss and long operations where possible.

Related: emergencies on call, how to do an AC tap, and EVS and ESCRS trials.