bubble_chart Overview

Purulent uveitis, also known as suppurative endophthalmitis, can begin in either the anterior or posterior uvea, with the disease progressing rapidly and violently. The pigment membrane tissue dissolves, leading to a large amount of purulent exudate. If diagnosis and treatment are inadequate, it can cause severe damage to the eye tissues, resulting in vision loss and eyeball atrophy.

bubble_chart Etiology

1. Exogenous: Due to ocular trauma, intraocular surgery, and perforation of corneal ulcers, bacteria directly enter the eye. Endophthalmitis caused by surgery is commonly induced by Gram-negative bacteria such as Pseudomonas aeruginosa. However, trauma-related cases are more frequently associated with fungi, anaerobic bacteria, and polymicrobial infections compared to postoperative infections. Typically, inflammation appears within 24–48 hours post-surgery. However, with the current routine subconjunctival injections of antibiotics and corticosteroids, endophthalmitis may be delayed and manifest 2–5 days after surgery. If pain worsens within 24–48 hours post-surgery, infection by more virulent microorganisms should be considered. Fungal endophthalmitis usually presents symptoms within 2–3 weeks after surgery or injury.

2. Endogenous: Endogenous (or metastatic) infectious endophthalmitis is often characterized by fungal infections and is caused by infections reaching the eye via the bloodstream. Pathogens may originate from distant foci of infection or systemic sepsis. The onset is usually insidious, with slow progression.

bubble_chart Clinical Manifestations

1. Suppurative choroiditis: Mainly affects the choroid and vitreous body. In the initial stage [first stage], there are no external signs of inflammation, but vision may be lost. A vitreous abscess forms, and a yellow reflex from the vitreous can be seen through the pupil. If the inflammation is not controlled and the vitreous abscess is not resolved, the inflammation can spread to the entire uvea, leading to endophthalmitis.

2. Suppurative endophthalmitis: Often caused by perforating trauma, extrusion of intraocular contents, or retained intraocular foreign bodies, where microorganisms enter the eye through the wound and rapidly spread, resulting in panuveitis. Patients experience sudden eye pain, tearing, and vision loss, with eyelid swelling, severe conjunctival congestion and edema, corneal opacity, yellow discoloration of the iris, constricted or irregular pupils, or pupillary membrane closure, along with pus accumulation in the anterior chamber and vitreous. Additionally, the inflammation can spread to tissues outside the eyeball and into the orbit, leading to panophthalmitis.

3. Panophthalmitis: Intraocular inflammation can spread through the scleral emissary canals, infecting the Tenon’s capsule and scleral tissues, while also causing suppurative inflammation within the eye. At this stage, intense eye pain and headache become unbearable. The pain results from highly toxic bacteria proliferating in the eye, producing proteases and purulent exudates, leading to elevated intraocular pressure or compression of the long posterior ciliary nerve by choroidal abscesses. Severe vision impairment or blindness occurs, with marked eyelid swelling and conjunctival congestion and edema, which may protrude through the palpebral fissure, and the eye becomes fixed. In severe cases, headache, nausea, vomiting, general malaise, high fever, and unconsciousness may occur. If the inflammation spreads intracranially, cavernous sinusitis or cavernous sinus syndrome may develop. The eyeball becomes filled with purulent exudates, and the cornea or sclera may necrose and perforate, allowing pus to drain and symptoms to alleviate, eventually leading to phthisis bulbi.

bubble_chart Treatment Measures

1. Systemic antibiotic therapy: Once the diagnosis is established, effective antibiotics should be administered immediately to achieve the required therapeutic concentration in the eye, particularly in the choroid membrane and retina. The combined use of two or more antibiotics can enhance the anti-inflammatory effect. Commonly used drugs include: penicillin, methicillin, and cefazolin administered intravenously or intramuscularly. Gentamicin is administered intramuscularly or intravenously, once or twice daily. Carbenicillin (10-15g) is dissolved in 300ml of normal saline and administered intravenously once daily. Amphotericin B is the drug of choice for fungal endophthalmitis.

2. Hormone therapy: The purpose of this treatment is to reduce inflammatory exudation and the formation of granulation tissue. However, its drawback is that it may weaken the bacteriostatic effect of antibiotics and reduce their ability to penetrate ocular tissues.

3. Intravitreal antibiotic injection: Commonly used antibiotics include: cefazolin 0.25mg or gentamicin 200u injected intravitreally. Gentamicin 200u plus dexamethasone 0.4mg; gentamicin 100u plus cefazolin 0.25mg. Amphotericin B 0.01mg can also be injected intravitreally.

4. Topical application of antibiotics and hormones or subconjunctival injection.

5. Surgical treatment: When there is a large amount of exudate in the anterior chamber, anterior chamber irrigation and antibiotic injection can be performed. For endophthalmitis, vitrectomy should be performed as early as possible, combined with intravitreal injection of antibiotics and hormones. If the inflammation cannot be controlled and vision is lost, evisceration may be performed.