To evaluate the distinguishing characteristics that may assist in the clinical diagnosis of sterile endophthalmitis from intravitreal triamcinolone injection.

From January 2005 to June 2006, the medical records of 163 eyes that received intravitreal triamcinolone injection were reviewed. In 5 eyes of 5 patients who complained of decreasing vision and mild ocular pain within three days after injection, slit lamp bimicroscopy revealed hypopyon, anterior chamber reaction, and vitritis. We analyzed clinical pictures retrospectively.

Intravitreal triamcinolone injections were performed for diabetic macular edema in 4 patients and for panuveitis in 1 patient with Behçet's disease. Pseudophakia was found in all five eyes. Inflammations in three eyes resolved with topical and oral antibiotics within 13 days, and the other two patients were treated with a vitreous culture and intravitreal antibiotic injection. However, vitreous tap showed no evidence of endophthalmitis, and inflammation resolved within the same period.

Presumed sterile endophthalmitis presents within 3 days after intravitreal triamcinolone injection and may be accompanied by decreased vision and ocular discomfort, although it is characterized by no distinct ocular pain. The symptoms and ocular inflammation resolved quickly within 13 days with a favorable visual outcome. Inflammations in three eyes resolved without surgical intervention, so it may be necessary to closely observe clinical manifestations before assuming that the eye is suffering from infectious endophthalmitis.