**25. Visual outcome in endogenous endophthalmitis**

to have fungal isolates with a predominance of Candida albicans. The most common Gram positive organisms are Staphylococcus aureus, group B streptococci, Streptococcus pneumo‐ niae,and Listeria monocytogenes; the most common Gram negative organisms are Klebsiella spp., Escherichia coli, Salmonella, Pseudomonas aeruginosa, and Neisseria meningitidis. [2,

The optimal treatment for endogenous endophthalmitis is controversial. When indicated, these patients may require systemic antibiotics in addition to the PPV. While EVS has provid‐ ed guidelines for the role of early vitrectomy and intra-vitreal antibiotics in post-operative en‐ dophthalmitis, no such study has addressed endogenous endophthalmitis. Data from the EVS may not be applicable to cases of endogenous endophthalmitis because the spectrum of caus‐ ative organisms differs significantly in endogenous endophthalmitis as compared to post-op‐ erative endophthalmitis. Although systemic and intra-vitreal antibiotics may be sufficient in milder forms of infection, PPV has been shown to be helpful in severe cases of endogenous en‐ dophthalmitis. More virulent organisms such as endotoxin-producing Streptococcus and Ba‐ cillus species are commonly involved in endogenous endopthalmitis. [67, 71] In addition, material from vitrectomy may provide a better source for culture. This is particularly true in children because of the variety of pediatric cases and lack of sufficient experience in diagnos‐ ing in this age group. [7] In the adults, early intervention with PPV has been found to be high‐ ly effective, no such data has been proven for cases of pediatric endogenous endophthalmitis. Suggested medical treatment in these patients include topical, sub-conjunctival and intra-vi‐ treal injection of antibiotics having broad coverage with consideration for corticosteroids in cases of severe inflammation. Patients with endogenous endophthalmitis should be evaluat‐ ed for underlying systemic conditions. Systemic anti-microbial therapy is the mainstay of en‐ dogenous endophthalmitis. Intravitreal antibiotic selection is similar to exogenous endophthalmitis including Vancomycin (1.0 mg/0.1 mL) for Gram-positive coverage or in combination with Ceftazidime (2.25 mg/0.1 mL) or Amikacin (400 ug/0.1 mL) for Gram-nega‐ tive coverage.. In general, systemic therapy must be continued for several weeks to ensure eradication of the infection. Generally, a combination of intra-vitreal antibiotics is injected that may include Vancomycin, Cephazolin or Ceftazidime and Amikacin after the tap has been performed. Systemic antibiotics are administered according to the focus of the infection. Infec‐ tious diseases consultation may be sought in cases of endocarditis and early vitrectomy should be planned if indicated. [88] Immediate vitrectomy is performed in eyes with lightperception-only vision at the initial visit. Routine immediate vitrectomy is not necessary in eyes presenting with better than light-perception vision. Aggressive therapy and early vitrec‐ tomy may be considered in endogenous endophthalmitis caused by virulent pathogens such Pseudomonas aeruginosa and in cases of Klebsiella endophthalmitis. [81, 97, 99] Patients with endogenous endophthalmitis who undergo PPV early in the course of endogenous endoph‐

**24. Management of endogenous endophthalmitis**

thalmitis may end up with some useful vision.

3, 69, 91]

198 Common Eye Infections

Endogenous endophthalmitis is generally associated with high mortality and poor visual outcomes, particularly when caused by more virulent species such as Aspergillus. [98] Fun‐ gal endopthalmitis has a poor visual outcome as compared to bacterial endophthalmitis. [100] The visual outcome in cases of treated Streptococcal endophthalmitis is generally poor than some of the Staphylococcal species. Patients with good initial VA typically have good final VA. It is believed that an active therapeutic approach including intra-vitreal antibiotics and vitreo-retinal surgery may save eyes from blindness. In the past, the visual outcome has been poor with most cases leading to blindness in the affected eye. [70, 81] In an experimen‐ tally model of endogenous endophthalmitis, infant rats inoculated by either intra-nasal or intra-peritoneal injection of Haemophilus influenzae type b, suppurative endophthalmitis occurred in 50% of bacteremic animals who survived. [101] This experimental induced en‐ dogenous endophthalmitis ultimately progressed to panophthalmitis followed by organiza‐ tion of the exudate and phthisis bulbi. Recent data for the effectiveness of vitrectomy and intra-vitreal antibiotics to save some vision has been encouraging. [88] Endophthalmitis due to Streptococcal species may result in earlier onset and perhaps worse visual outcome. On the other hand, endophthalmitis which yields no positive results from culture usually have delayed onset of infection and better visual results.
