Five-Year Risk and Safety Profile of Autologous Serum Eye Drop Therapy

Purpose To evaluate the risk and safety profile of autologous serum eye drop therapy in clinical routine over a period of 5 years. Methods This retrospective study involved all patients treated with autologous serum between July 2014 and December 2019 at a tertiary ophthalmic referral center. The electronic patient record system was searched for all patients with autologous serum eye drop therapy at any time point. These records were subsequently searched for keywords such as infectious keratitis, corneal ulcer, conjunctivitis, or endophthalmitis at any recorded contact. The probability of an association between the therapy with autologous serum eye drops and infectious complications was investigated independently by three corneal specialists and rated as likely, potential, or unlikely. Results In total, 752 patients were treated with autologous serum eye drops between July 2014 and December 2019. There were 5 384 batches with a total of 107 680 bottles of serum eye drops that had been produced and dispensed for these patients during this period. The records of 291 patient showed a combination of autologous serum therapy and at least one keyword for infectious diseases. In 288 patients, individual case analyses revealed an unlikely association between the therapy and infection, as their infectious episodes occurred either before the start of the therapy, more than 1 month after the therapy ceased, or in the contralateral untreated eye in the case of unilateral therapy. Three cases of infectious keratitis were classified as potentially associated with autologous serum therapy. However, all three patients suffered from chronic anterior eye diseases with a high risk of spontaneous infectious complications independent of therapy with autologous eye drops. None of the infectious events was rated as being likely due to the serum eye drops. Conclusions Serum eye drops are often used in patients with severe or chronic anterior eye diseases with an intrinsic risk of infectious diseases. Despite these preexisting risk factors, autologous serum eye drops can be considered safe, even in patients with a compromised ocular surface.