Fungal endophthalmitis is a rare, severe infection affecting the inner parts of the eye, specifically the vitreous and aqueous humor. If not diagnosed and treated promptly, it carries a high risk of permanent vision loss.
Understanding Fungal Endophthalmitis
Fungal endophthalmitis is an inflammation of the eye’s internal fluids, such as the vitreous (the jelly-like substance in the back of the eye) and aqueous humor (the fluid in the front of the eye), caused by a fungal infection. The fungi responsible for these infections vary by region, but common types include Candida species, Aspergillus species, and Fusarium species. Candida albicans is frequently implicated in endogenous cases, while Aspergillus and Fusarium are often seen in exogenous infections.
The infection enters the eye through one of two main routes: exogenous or endogenous. Exogenous fungal endophthalmitis occurs when fungal spores enter the eye from an external source, often following eye surgery, injections into the eye, or eye trauma. For instance, post-cataract surgery fungal endophthalmitis is rare, with an incidence of about 0.002% to 0.005% in the United States. Endogenous fungal endophthalmitis, which is less common, results from a fungal bloodstream infection spreading to the eye from another part of the body. This type is more prevalent in individuals with compromised immune systems.
Several factors can increase an individual’s susceptibility to fungal endophthalmitis. Recent eye surgery, such as cataract surgery, or penetrating eye injuries are significant risk factors for exogenous infections. For endogenous infections, conditions that weaken the immune system, like diabetes, HIV, or prolonged use of corticosteroids, increase the risk. Intravenous drug use, long-term antibiotic use, and the presence of central venous catheters are also associated with a higher likelihood of developing endogenous fungal endophthalmitis.
Recognizing the Signs
Common symptoms include eye pain, redness, blurred vision, and a decrease in overall visual acuity. Individuals may also experience sensitivity to light, known as photophobia, and the appearance of floaters or dark spots in their vision. In some cases, there might be white or yellow discharge from the eye or swollen eyelids.
The onset of symptoms can vary, depending on the type of fungus and how the infection entered the eye. Exogenous infections, particularly after surgery or trauma, may present with symptoms within a few days, indicating an acute onset. However, fungal endophthalmitis can also develop more gradually, with symptoms worsening over days to weeks, which is often seen in endogenous cases or with certain fungal species like Candida. Aspergillus endophthalmitis, however, can lead to rapid progression of severe vision loss.
Any new or worsening eye symptoms, especially following eye surgery or trauma, warrant immediate medical attention. Prompt evaluation can help differentiate fungal endophthalmitis from other less severe eye conditions and ensure that appropriate treatment begins as quickly as possible.
Diagnosis and Treatment
Diagnosing fungal endophthalmitis involves a thorough assessment due to its variable clinical presentation. The process begins with a comprehensive eye examination, where the ophthalmologist looks for signs of inflammation within the eye, such as vitreous exudates or haze. Imaging tests, like ocular ultrasound, can provide additional information about the extent of the internal eye inflammation. However, the definitive diagnosis relies on laboratory analysis of fluid samples taken directly from the eye, often through a vitreous tap or a vitrectomy, to identify the specific fungus causing the infection. Blood cultures may also be performed, especially if an endogenous infection is suspected, though they are positive in only about one-third to one-half of confirmed endogenous cases.
Once diagnosed, treatment primarily involves antifungal medications and, in some instances, surgical intervention. Antifungal drugs can be administered through various routes, including oral pills, intravenous infusions, or direct injections into the eye (intravitreal injections). For instance, intravitreal amphotericin B or voriconazole are common choices for direct eye injection. Systemic oral or intravenous antifungal medications, such as voriconazole or fluconazole, are also used, sometimes in combination with intravitreal injections, depending on the specific fungus and infection severity.
Surgical intervention, specifically a pars plana vitrectomy, plays a role in managing more severe cases. This procedure involves the surgical removal of the infected vitreous gel, which helps to reduce the fungal load within the eye and can improve the penetration of antifungal medications. Vitrectomy can also be performed to obtain a larger vitreous sample for diagnosis. Early vitrectomy can decrease the incidence of complications like retinal detachment. The prognosis for fungal endophthalmitis varies, but early diagnosis and aggressive, tailored treatment significantly improve outcomes.
Prevention Strategies
Preventing fungal endophthalmitis focuses on minimizing exposure to fungi, particularly for individuals at higher risk. Strict adherence to sterile techniques during all eye surgeries and injections is paramount, including meticulous hand hygiene and preparation of the surgical site.
For individuals who experience eye injuries, proper and prompt wound care is important to prevent fungal entry. This includes cleaning the wound thoroughly and seeking medical attention for deep or contaminated injuries. Contact lens wearers should practice safe hygiene, including washing hands before handling lenses, using fresh solution, and avoiding tap water, to reduce contamination risk.
Managing underlying health conditions that compromise the immune system, such as diabetes or HIV, helps to reduce the risk of endogenous infections. This involves consistent medical management and following healthcare provider recommendations.