From the Guidelines
Exogenous endophthalmitis most commonly occurs through direct inoculation of microorganisms into the eye following trauma or surgery. This route of infection can introduce a variety of pathogens into the eye, including gram-positive organisms, environmental organisms such as dematiaceous fungi, and glucose fermenting gram-negative rods 1. The spectrum of causative agents in exogenous endophthalmitis varies depending on the mode of pathogenesis, with post-operative endophthalmitis often caused by gram-positive organisms like coagulase-negative staphylococci, and chronic post-operative endophthalmitis sometimes due to P. acnes 1.
Some key points to consider in the context of exogenous endophthalmitis include:
- The importance of proper surgical technique and preoperative antisepsis with povidone-iodine to reduce the risk of infection
- The role of perioperative antibiotics in preventing post-operative endophthalmitis
- The need for maintaining sterile conditions during any invasive ocular procedure to minimize the risk of introducing pathogens into the eye
- The potential for compromised wound closure, prolonged surgery, or pre-existing conditions like blepharitis to increase the risk of exogenous endophthalmitis
In terms of specific routes of infection, trauma-related endophthalmitis occurs when foreign bodies penetrate the eye, carrying microorganisms from the environment or skin, while intravitreal injections can create a direct pathway for pathogens to enter the vitreous cavity 1. Less commonly, contaminated irrigation solutions or intraocular lenses can introduce pathogens during surgery. Understanding these routes of infection is crucial for implementing effective preventive measures and recognizing high-risk situations that may require more aggressive prophylaxis.
From the Research
Exogenous Endophthalmitis Route
- Exogenous endophthalmitis occurs when infecting organisms gain entry into the eye via direct inoculation 2
- The route of infection can be through ocular surgery, penetrating ocular trauma, or intraocular foreign bodies 3
- Exogenous endophthalmitis can also occur when pathogens enter the eye through direct inoculation, as opposed to endogenous endophthalmitis which develops when pathogens get into the eye through the hematogenous route from a distant infection focus 4
Causes of Exogenous Endophthalmitis
- Post-cataract extraction surgery is a common cause of exogenous endophthalmitis 5
- Post-intravitreal injection is also a common cause of exogenous endophthalmitis 5
- Penetrating ocular trauma and intraocular foreign bodies can also lead to exogenous endophthalmitis 3
Diagnosis and Treatment
- Diagnosis of exogenous endophthalmitis depends mostly on clinical findings on ophthalmological examination 2
- Early diagnosis and proper treatment are keys to saving the eye 2, 4
- Prompt intravitreal antimicrobial therapy is key to successful management of exogenous endophthalmitis, and vitrectomy is essential in severe cases 3
- Early surgical intervention is the current trend in the management of endophthalmitis 2