# Endophthalmitis > Endophthalmitis for MBBS Ophthalmology: postoperative and post-traumatic hypopyon vitritis, EVS vitrectomy criteria, intravitreal vancomycin ceftazidime. - Canonical URL: https://prepelephant.com/topics/mbbs/ophthalmology/endophthalmitis - Exam / course: MBBS · Subject: Ophthalmology - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-02 - Last updated: 2026-10-02 - How to cite: "Endophthalmitis", PrepElephant, https://prepelephant.com/topics/mbbs/ophthalmology/endophthalmitis ## Direct answer Endophthalmitis is inflammation of the intraocular cavities and adjacent ocular coats, nearly always infective, classified as exogenous (postoperative — the commonest; post-traumatic; or post-injection) or endogenous (haematogenous spread from a liver abscess or endocarditis). The presentation is a red, painful, sight-threatened eye days to weeks after surgery or trauma, with lid oedema, hypopyon, severe anterior chamber inflammation, vitritis and loss of the red reflex. Treatment is an emergency: aqueous and vitreous taps for microscopy and culture with intravitreal antibiotics — vancomycin plus ceftazidime (or amikacin) — guided by the Endophthalmitis Vitrectomy Study, which showed vitrectomy benefits eyes with light perception only and that systemic antibiotics added little postoperatively. Post-traumatic cases with soilage carry the worst prognosis, Bacillus cereus being the notorious organism. ## What you must remember - **Categories and their clocks:** acute postoperative (within six weeks, typically days 1-5) — coagulase-negative staphylococci and Staphylococcus aureus; delayed postoperative — Propionibacterium (now Cutibacterium) acnes and fungi; post-traumatic — often polymicrobial, with Bacillus cereus after wooden foreign bodies producing devastation within 24-48 hours; endogenous — Klebsiella pneumoniae from a liver abscess is the classic Indian association with poor prognosis, plus Candida in line-sepsis. - **Clinical picture:** pain out of proportion to the surgical expectation, eyelid oedema, chemosis, intense injection, hypopyon, fibrin, vitritis obscuring the fundus and a poor red reflex; endogenous cases may present subtly in a septic patient. - **The EVS verdicts to quote:** in postoperative endophthalmitis, immediate pars plana vitrectomy improved outcomes only in eyes with light-perception vision; intravitreal antibiotics benefited all severities; systemic antibiotics of that era added no benefit. - **Intravitreal regimen:** vancomycin 1 mg in 0.1 mL plus ceftazidime 2.25 mg in 0.1 mL (amikacin as the aminoglycoside alternative), repeatable at 48-72 hours; amphotericin or voriconazole for fungal disease; adjunctive fortified topicals, cycloplegics and topical steroids. - **Sample before therapy:** aqueous and vitreous taps for Gram stain, culture and sensitivity — therapy must not wait for results but must be preceded by the sample. - **Prevention details examiners like:** povidone-iodine 5-10% ocular surface antisepsis before surgery is the most evidence-based step; proper wound construction; treatment of chronic dacryocystitis and blepharitis before elective intraocular surgery; and vigilance after intravitreal injections, now a leading iatrogenic cause. - **Differential in the early postoperative eye:** toxic anterior segment syndrome — sterile, within 24 hours, from solution or instrument contaminants, with corneal oedema, minimal pain and no vitritis; it resolves with topical steroids, and mistaking it either way changes therapy unnecessarily. - **Prognosis anchors:** final vision correlates with organism virulence and timing — coagulase-negative Staphylococcus does best; streptococci, Bacillus and gram-negatives worst; endogenous Klebsiella cases in India often present late with poor salvage. ## How to work through day-four pain after cataract surgery A 68-year-old diabetic woman phones on the fourth evening after uneventful phacoemulsification: increasing pain, redness and vision fallen to hand movements. She is seen the same night: lids swollen, intense injection, a 2 mm hypopyon, fibrin across the pupil and no fundus view. Reason it aloud: acute postoperative endophthalmitis until proven otherwise — a same-night plan, not a next-day review. Acuity is hand movements (better than light perception), so per EVS logic she needs tap-and-inject: aqueous and vitreous samples for Gram stain and culture, then intravitreal vancomycin and ceftazidime, with fortified topicals, cycloplegia and review at 24-48 hours for repeat injection if uncontrolled. Culture grows coagulase-negative Staphylococcus; two weeks later the eye is quiet at 6/18. The counterfactuals the examiner wants: light-perception-only vision means immediate vitrectomy; a farm injury with a wooden intraocular foreign body and day-one hypopyon means assume Bacillus cereus with guarded prognosis and vitrectomy with foreign-body removal; a quiet, achy eye 6 weeks after surgery with a white plaque in the capsular bag is delayed C. acnes endophthalmitis needing partial capsulectomy with intravitreal vancomycin. ## Where students slip Two slips dominate. First, delay: waiting for morning, or for culture reports before treating, forfeits the eye — the sample precedes the injection, but both happen the same hour. Second, protocol confusion: intravenous antibiotics are not the primary therapy — the EVS position is that intravitreal antibiotics treat the disease and systemic therapy adds little postoperatively (endogenous and post-traumatic cases differ, and systemic agents are used there alongside the intravitreal route). Also separate TASS from infection on day one: sterile, painless, cornea-oedematous, no vitritis — a distinction that changes therapy completely. ## Frequently asked questions ### How is endophthalmitis classified? Exogenous — postoperative, post-traumatic or post-injection, from organisms entering the eye — and endogenous, from haematogenous seeding: Klebsiella liver abscess, candidaemia. ### What did the Endophthalmitis Vitrectomy Study conclude? Immediate vitrectomy improved outcomes only in eyes with light perception vision; intravitreal antibiotics were essential across severities; systemic antibiotics added no benefit in post-cataract endophthalmitis as tested. ### Which intravitreal antibiotics form standard empirical therapy? Vancomycin 1 mg per 0.1 mL plus ceftazidime 2.25 mg per 0.1 mL (or amikacin), injected after aqueous and vitreous sampling, repeatable at 48-72 hours. ### Which organism makes post-traumatic endophthalmitis feared? Bacillus cereus, classically after wooden foreign-body injuries, producing destruction within 24-48 hours and a guarded prognosis despite early vitrectomy. ### How is TASS different from acute postoperative endophthalmitis? Toxic anterior segment syndrome is sterile, appears within a day of surgery, is relatively painless with corneal oedema and a mid-dilated pupil, lacks vitritis, and responds to intensive topical steroids.