Intravitreal Injections and Secondary Sterile Endophthalmitis

Sterile endophthalmitis appears as an infrequent complication of intravitreal injections and seems to
develop mainly in the context of the off-label use of drugs that have not been conceived for
intravitreous administration. The aetiology of sterile endophthalmitis, independently of the
administered drug, remains uncertain and a multi-factorial origin cannot be discarded. Sterile
inflammation secondary both to intravitreal triamcinolone acetonide and to intravitreal bevacizumab
share many characteristics such as the acute and painless vision loss present in the big majority of
the cases. Dense vitreous opacity is a common factor, while anterior segment inflammation appears
to be mild to moderate. In eyes with sterile endophthalmitis, visual acuity improves progressively as
the intraocular inflammation reduces without any specific treatment. If by any chance the
ophthalmologist is not convinced of the sterile origin of the inflammation, this complication must be
treated as an acute endophthalmitis because of the devastating visual prognosis of this intraocular
infection in the absence of therapy.