Endophthalmitis as a Serious Complication of Intravitreal Drug Delivery

Background: Endophthalmitis, regarded as a severe complication, can occur after intraocular injection of drugs (IVI). At present only few reports exist on the development of this disease, although recently the number of intraocular injections to treat especially age-related macular degenerations is increasing considerably. Methods: In this paper we present our results of a retrospective study of 27 patients suffering from endophthalmitis after IVI. Treatment had been performed between January 2008 and March 2012. The indications for IVI were as follows: age-related macular degeneration 19, venous branch occlusion 1, diabethic retinopathies 6, uveitis 1. The following drugs were injected: bevacizumab in 8, Rranibizumab in 19 patients. The following data were assessed: incubation time, best corrected visual acuity that had been determined before treatment and later 3, 6 and 9 months after therapeutic vitrectomy. Additionally we describe the ophthalmoscopic changes and the results of bacteriological studies. Results: Endophthalmitis was diagnosed 5.8 days after IVI on average. The vision of all patients had only been hand movements during the first examination. During the observation time the postoperative visual acuity could be improved only to 1/35 on average. During vitrectomy in 24 out of 27 patients a whitish retinal infiltration could be observed. 18 of 27 patients showed a hypopyon during slit lamp examination. 11 patients developed a retinal detachment and one eye had to be enucleated. Conclusions: Endophthalmitis must be regarded as a severe complication causing a high risk of retinal detachment with permanent loss of visual acuity. Retinal infiltrations and haemorrhages occur already in the early stages and cause finally a very poor prognosis. The incubation time as a rule amounts to 6 days. The increasing number of IVI and the high risk of damaged retinal structures due to intraocular infections should make postoperative retinal follow-up examinations mandatory, especially during the first 6 days.