In which cases of post-injection endophthalmitis should early vitrectomy be considered if there is little to no improvement 48 hours after a tap and inject and there is no organism isolated?  

Prompt vitrectomy should be considered in all patients with post-injection endophthalmitis (PIE) if there is no improvement 48 hrs after a tap and inject. The initial tap did not identify the organism. Non-infectious endophthalmitis can be included in the differential diagnosis of persistent inflamm...

While I agree with my colleagues above, I feel compelled to point out several observations I have made over the years. There really isn't any great data along the lines of the EVS for post-injection endophthalmitis. Post-injection endophthalmitis is by far more common as a percentage than post-sur...

Yes. Sometimes a vitrectomy is helpful to debulk the infection and allow the antibiotics to spread through the vitreous cavity. I only do a core vitrectomy in these cases, as the retina can be quite friable, and attempting to lift the hyaloid can cause a detachment or tear.