Assessment the microbial contamination rate of re-used vials of bevacizumab(Avastin) and the risk of endophthalmitis.

Introduction of anti-VEGF therapy has revive the way of management to the retinal diseases .Pegaptanib (macugen)was the first to be approved and was followed by other agents ,including ranibizumab(Lucentis,Genentech,San Francisco,Calif.) ,bevacizumab (Avastin,Genentech) and aflibercept (Eylea,Regeneron,Tarrytown,N.Y.)Studies have shown the safety and efficacy of these agents in the treatment of wet ARMD ,RVO and DME .These drugs delivered into the vitreous cavity through pars plana injection ,and are generally safe with little serious complications. Aim :To evaluate the rate of microbial contamination and safety aspects of multi puncture vials of bevacizumab(Avastin) and to determine the rate of endophthalmitis in patients who received intravitreal injections .Methods :A multi-centric prospective study conducted at the Basrah general teaching hospital and Al-zubair general hospital , Basrah ,Iraq, a total of of 28 consecutive vials of bevacizumab {Avastin;F.Hoffmann-LaRoche Ltd.Switzerland}were used .A total 1096 injections were administered to 899 patients between sept. 2019 and Nov. 2024.After puncture the vial ,multidoses used for intravitreal injections , residue bevacizumab in the vial was stored in the refrigerator at 2-8c and reused for up to 4 weeks .From each vial, sample of 0.05was withdrawn with the sterile 1ml syringe under aseptic technique at week 1,2,3 and 4th after opening the vial.These samples were sent for bacterial gram staining and culture .Patients who received the injections were given topical antibiotic eye drops and monitored for the signs and symptoms of inflammation or endophthalmitis for 6 weeks.Results: No evidence of microbial contamination was detected in 28 vials as approved by the results of microbial staining and culture.One patient of 899 patients who received intravitreal injections from these vials showed signs of inflammation,otherwise; no evidence of endophthalmits.Conclusion: Use multidoses Avastin vial after opening is safe.