Antibiotico resistenza congiuntivale secondaria ad incongruo utilizzo sistemico di antibiotici

Antibiotic resistance in ophthalmology is an escalating public health concern, with a significant rise in cases of ocular infections resistant to conventional antibiotics. This prospective, interventional, non-randomized study involved 100 patients undergoing cataract surgery between January and September 2024 at the AOU Federico II in Naples, in collaboration with the University of Molise. Patients were divided into two groups: Group 1 (n=50), with a history of recurrent urinary tract infections treated with systemic antibiotics, and Group 2 (n=50), without such a history. Both groups received topical treatment with a 0.5% ozonized oil in liposomes eye drop formulation for three days prior to surgery. Conjunctival swabs were collected at baseline (T0) and immediately before surgery (T3) for microbiological analysis to identify bacterial pathogens and assess antibiotic susceptibility. The results demonstrated a significant reduction in bacterial load in both groups. Microbiological analysis revealed a predominance of Gram-positive bacteria, particularly Staphylococcus epidermidis, and an increasing resistance to various antibiotic classes, including fluoroquinolones and aminoglycosides, notably in Group 1. These findings suggest a selective pressure exerted by systemic antibiotic use, leading to the emergence of resistant strains, even to ophthalmic antibiotics, highlighting the risk of cross-resistance. The ozonized oil treatment exhibited comparable efficacy in reducing bacterial load and preventing postoperative infections across both groups, irrespective of prior antibiotic exposure. Furthermore, the treatment demonstrated high tolerability in both groups. Previous systemic antibiotic use may contribute to the emergence of resistant ocular strains, posing a risk of cross-resistance. Ozonized oil demonstrated high efficacy and tolerability, supporting its potential as a non-antibiotic antiseptic alternative in ophthalmology to address the growing challenge of antibiotic resistance.