Topical Linezolid for Refractory Bilateral Mycobacterium chelonae Post–Laser-Assisted In Situ Keratomileusis Keratitis

Abstract

not emphasized in previously reported cases: (1) early diagnosis; (2) successful combination of topical, oral, and intraocular therapy with drugs that can reach therapeutic levels in aqueous and vitreous 4,5 and are effective in vivo 6 for other Acanthamoeba infections; and (3) guiding treatment by effective monitoring of the response by Acanthamoeba.We think oral and topical administration of voriconazole must have achieved a sustained therapeutic dose and frequent administration of intraocular voriconazole produced high peak levels, increasing effectiveness. Topical chlorhexidine was used before the PK but the keratitis worsened, raising the question of its effectiveness in our patient. It is unknown whether topical chlorhexidine can reach aqueous therapeutic levels; however, rabbit studies have shown that frequent instillation of chlorhexidine, 0.02%, in epithelialized corneas 7 produces concentrations 10 to 40 times lower than voriconazole but, in our experience, a similar 90% inhibitory concentration. Moreover, in the other described cases, topical antiseptics such as chlorhexidine used after PK did not prevent endophthalmitis. Therefore, we believe chlorhexidine did not play a major role in our case. The susceptibility of Acanthamoeba to trimethoprim/sulfamethoxazole, also used in our patient, is based on a few reports 8 ; we have not tested the susceptibility of the patient's strain and cannot be sure of its real contribution.

Mycobacterium chelonae Keratitis following Keratorefractive Lenticule Extraction: Highlighting Diagnostic and Treatment Complexities

“…Fortunately, these infections remain infrequent, with a reported incidence of 1 in 5,000 to 10,000 procedures [ 5 , 6 ]. Typically, they manifest as conjunctival inflammation and a prominent corneal infiltrate, primarily involving the edge of the treatment zone [ 5 , 7 , 8 ]. Atypical mycobacteria and Gram-positive bacteria are the most common infectious organisms attributed to post-refractive keratitis [ 6 ].…”

Late-Onset Nontuberculous Mycobacterial Keratitis After Small Incision Lenticule Extraction

“…1,10 Topical linezolid could be an option for multidrug-resistant M. chelonae keratitis after LASIK. 11 The length of medical treatment is typically prolonged with no specific guidelines regarding the treatment duration. In a post-LASIK M. chelonae keratitis series, treatment duration ranged from 31 to 51 weeks (mean 41 wk).…”

Minimum inhibitory concentrations and resistance for selected antimicrobial agents (including imipenem, linezolid and tigecycline) of bacteria obtained from eye infections

“…Topical use of both imipenem and linezolid has been reported in few cases of corneal infections [14][15][16][17][18][19][20][21]. Furthermore, Elsahn et al reported that 21 isolates of Staphylococcus aureus and 29 of methicillin-resistant coagulasenegative Staphylococcus recovered from infectious keratitis cases showed 100% in vitro susceptibility for linezolid [22].…”