Редкие инфекции после лазерной коррекции зрения требуют новых протоколов лечения

Keen awareness of new threats and thorough preparation vital in laser vision correction Key takeaways: - Atypical clinical presentations should increase suspicion for infection from newer pathogens. - Refractive surgical teams should be familiar with and apply strict aseptic practices in ophthalmic surgeries. Infections associated with laser vision correction procedures remain a rare but potentially devastating occurrence. Precise rates of infection are uncertain due to underreporting and incomplete reporting. Estimates suggest an approximate incidence rate of one in 5,000 LASIK procedures and one in 1,000 surface ablation procedures, higher in part due to breach of the corneal epithelial barrier and use of a therapeutic contact lens. Around 2000, a shift in the organisms recovered in laser vision correction (LVC)-associated infections was observed from common pathogens such as staphylococci, streptococci and pseudomonal species to less common, “atypical” pathogens, including species of nontuberculous mycobacteria (Freitas et al.; John et al.). Investigations of cluster outbreaks often identify the role of water and contaminated equipment in the outpatient environment as sources of these opportunistic causative pathogens (Freitas et al.). Treatment was challenging and protracted, and it often resulted in suboptimal outcomes (Freitas et al.; John et al.). Earlier this year, the CDC disseminated an alert of a newer threat with an outbreak of Purpureocillium lilacinum keratitis in three patients undergoing outpatient surface ablation LVC in an ophthalmology clinic in New York in late 2024 (Chang et al.). This filamentous fungus (formerly Paecilomyces lilacinum) is an environmental mold that in immunocompetent individuals is a rarer cause of mycotic keratitis after ocular trauma, contact lens wear or ophthalmic surgery. The organism (Figure 1) can cause deep, fulminant, severe keratitis often recalcitrant to conventional antifungal treatments, resulting in keratolysis with corneal perforation and/or contiguous scleral spread. In the 2024 outbreak, all three patients underwent surface ablation with use of an epikeratome. Environmental cultures were negative for P. lilacinum, but fungal amplicon sequencing detected P. lilacinum DNA in the epikeratome suction tubing. A number of deficiencies in infection prevention and control practices were detected during the investigation of the office-based clinical environment where the LVC took place. Cool mist humidifiers were in use, which have been previously implicated in Mycobacterium chelonae ocular infections (Edens et al.). Current health care engineering guidelines specify that steam humidification should be used. P. lilacinum is less susceptible to polyene antifungal agents, and treatment with amphotericin B and natamycin has been linked to poorer clinical outcomes (Chang et al.). Aggressive treatment of P. lilacinum keratitis with off-label use of azole antifungals topically (voriconazole), intrastromally (voriconazole) and orally (posaconazole) is recommended over polyene antifungal agents. Careful monitoring of systemic hepato- and cardiotoxicity is required in collaboration with appropriate subspecialists. Despite this antifungal treatment, many cases may progress such that therapeutic keratoplasty is performed before further spread or corneal perforation. With the reported outbreak after LVC, one of three cases of severe P. lilacinum keratitis went on to corneal perforation requiring therapeutic keratoplasty (Chang et al.). While P. lilacinum has been a rarer cause of fungal keratitis compared with other filamentous fungi (ie, Fusarium and Aspergillus species), recovery rates from commercial microbiological laboratories have demonstrated recently increasing detection of P. lilacinum from 2019 to 2025 (Smith et al.). This observed increase may be due to the intentional introduction of P. lilacinum as a bionematocide in agricultural control of plant parasites. P. lilacinum should be considered as a potential cause of severe, drug-resistant keratitis with LVC procedures. Heightened awareness of atypical clinical presentations should increase suspicion for early infection from newer pathogens in patients undergoing LVC procedures. Prompt diagnosis is essential, as often there is a significant delay in proper diagnosis and initiation of aggressive selective antifungal treatment (topical, intracorneal and systemic), with immediate suspension topical corticosteroid medications. LVC is corneal surgery, and the refractive surgical team should be familiar with standard aseptic practices in ophthalmic surgeries with strict adherence to infection control and prevention practices. Lessons learned dating from the inception of laser keratorefractive procedures emphasize “prior proper preparation preventing poor performance.” For more information: Terrence P. O’Brien, MD, a Healio | OSN Cornea/External Disease Board Member and professor of ophthalmology and Charlotte Breyer Rodgers Distinguished Chair at Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, can be reached at [email protected].