**6. Endophthalmitis post-intravitreal injections**

The use of intravitreal agents (e.g., Anti-VEGF and steroids ) to treat various retinal diseases has increased significantly since the 1990s.

The incidence rate of infectious endophthalmitis after intravitreal injection is low when compared to other post-surgical infectious endophthalmitis, it varies between 0.038% and 0.053% [36].

The most commonly causative pathogens are Streptococcus or Staphylococcus species suggesting the commensal flora of the ocular adnexa and oropharynx as the source. Published reports confirmed that Streptococcus is significantly more frequent after intravitreal injection than after other intraocular surgeries [37, 38].

The use of post-injection antibiotics does not decrease the frequency of subsequent endophthalmitis; however, it may possibly cause drug-resistant bacteria in the nasopharynx [39].

Post-intravitreal infectious endophthalmitis should be differentiated from sterile endophthalmitis, a well-recognized condition that can occur after intravitreal injections. In the latter patients present with painless reduction in vision, no or minimum redness, anterior chamber cells, fibrin, and/or hypopyon. In the MARINA trial, there was a 1% rate of serious inflammation in patients who received intravitreal injection with ranibizumab [40].

In contrary, the presentation post-intravitreal infectious endophthalmitis is more aggressive similar to the presentation seen after other intraocular procedures; this may include significant painful loss of vision, marked anterior chamber cells, fibrinous reaction, hypopyon, and/or vitritis [41].

The outcome is variable. In a large series of post-intravitreal infectious endophthalmitis; most of the eyes that developed (15 of 23) returned to baseline vision within 3 months after treatment and there was no significant difference in the rate of endophthalmitis between the types of anti-VEGF injected [42].
