Serious eye infections must be diagnosed and treated promptly to avoid permanent loss of vision. The three main categories of vision-threatening eye infections that need to be considered are keratitis, uveitis, and endophthalmitis.
• What are the most common causes of keratitis?
In the United States, the most common causes of keratitis are herpes simplex, which causes either an epithelial or an interstitial keratitis, and bacterial infections, which typically cause ulcerative keratitis and are associated with the use of contact lenses.
• What are the most common infectious causes of uveitis?
Ten percent of all cases of anterior uveitis and 50% of cases of posterior uveitis are caused by infection. Herpes simplex virus type 1 causes most infectious cases of anterior uveitis, whereas toxoplasma and cytomegalovirus are important causes of posterior uveitis.
Morning Report Questions
Q: How should endogenous endophthalmitis be treated?
A: Endogenous endophthalmitis is treated by direct intravitreal injection of antibiotics to treat the endophthalmitis and systemic therapy to treat the underlying bacteremia or fungemia. Systemic antibiotics alone do not clear endophthalmitis; intravitreal injection of antibiotics is essential. Vitrectomy, or surgical debridement of the vitreous, may be important in severe cases to rapidly clear the vitreous and protect the retina from further damage by microbes and inflammatory cells.
Q: What is the visual prognosis for cases of aspergillus endophthalmitis?
A: In cases of aspergillus endophthalmitis, the visual prognosis is usually very poor; more than three quarters of patients are left with a visual acuity that is limited to being able to count fingers or worse in the affected eye. Early diagnosis and prompt and aggressive treatment are important for the recovery of vision.
Table 2. Differential Diagnosis of Posterior Uveitis with Vitritis.