Effect of Liposomal-Lactoferrin-Based Eye Drops on the Conjunctival Microflora of Patients Undergoing Cataract Surgery

INTRODUCTION: Postoperative endophthalmitis is typically caused by the patient's conjunctival bacterial flora. Povidone iodine solution (5%) is used perioperatively to obtain periocular and ocular antisepsis. However, an adjunctive prophylaxis procedure could further help control the conjunctival microbial load. Considering the increase in antibiotic resistance, a progressive shift toward alternative methods would be desirable. Somilux(®) eye drops (Alfa Intes, lactoferrin-based eye drops) are medical devices containing liposomal lactoferrin (LF). This study evaluates the effects on conjunctival microflora of LF-based eye drops used in the preoperative phase in patients scheduled for cataract surgery. METHODS: LF-based eye drops or a vehicle solution (water solution) were instilled 4 times a day starting 3 days before cataract surgery. Before the therapy (T0) and at the time of surgery (T1), a conjunctival swab was performed in both eyes and processed to detect microbial growth, microbiological isolation, and species identification. The outcome was the quantification and characterization of the local microbial flora before and after using LF-based or vehicle-based eye drops. Safety of the treatments was also evaluated. RESULTS: 88 eyes of 44 patients (mean [± SD] age 75 [± 12.6] years) were enrolled. At baseline, 54 conjunctival swabs showed only saprophytic flora, 27 showed only potential pathogenic flora, and seven showed both of them. LF-based eye drops reduced the proportion of potentially pathogenic bacteria (36% at T0 vs. 9% at T1, p = 0.008) compared with the vehicle (41% at T0 vs. 55% at T1, p = 0.302) without altering the physiological ocular microbial composition. No adverse events have been reported. CONCLUSION: Our findings provide a novel contribution to the scientific knowledge on the role of LF in the ophthalmic field, supporting the use of LF-based eye drops as a safe and selective treatment to improve the ocular surface physiological defenses and control the bacterial ocular surface contamination prior to cataract surgery.