Purpose To report successful medical management of Pythium insidiosum keratitis using an antibiotic combination of minocycline, linezolid, and chloramphenicol. Observations A 20-year-old Japanese man was referred for visual disturbance, hyperemia, and discharge from his right eye. Slit-lamp examination revealed a paracentral corneal hyphate ulcer. His visual acuity was 20/28. Smear examination of corneal scrapings revealed a filamentous fungus. Pimaricin ointment four times a day and voriconazole eye drops hourly were initially prescribed. Although intravenous liposomal amphotericin B 100 mg was added, the corneal infiltrates and ulcer worsened. The possibility of P. insidiosum keratitis was considered, and in vitro antifungal susceptibility testing were performed based on the disc diffusion method. The inhibition zones around each antibiotic disc revealed that the pathogen was susceptible to minocycline, linezolid, and chloramphenicol. Therefore, minocycline ointment four times a day, chloramphenicol eye drops hourly, and linezolid 1200 mg orally per day were also administered. Eventually, sequencing of ribosomal DNA confirmed the pathogen to be P. insidiosum . The triple regimen dramatically improved the patient's keratitis. Therapeutic penetrating keratoplasty for corneal perforation was successfully performed, and his visual acuity recovered from 20/2000 to 20/25. Conclusions and importance We have encountered a case of P. insidiosum keratitis that responded to a combination of minocycline, linezolid, and chloramphenicol. This triple combination should be considered in patients with P. insidiosum keratitis.

Objectives: To characterize higher-order aberrations (HOAs) in clinical and subclinical keratoconus (KC). Methods: The study included 33, 36, and 26 patients with clinical, topographic (no clinical signs), and pretopographic (normal topography and no clinical signs) KC and 30 controls. Ocular and corneal HOAs for the 4-mm pupils were measured using a wavefront sensor and expanded up to the sixth order of Zernike polynomials. The magnitudes of trefoil, coma, tetrafoil, secondary astigmatism, and spherical aberration were calculated via Zernike vector analysis and used as HOA parameters along with total HOAs. Area under the receiver operating characteristic curve (AUROC) values for each wavefront parameter for pretopographic KC were compared. Results: Control eyes and eyes with pretopographic KC had significantly lower ocular or corneal total HOAs and Zernike vector terms than those with clinical KC and topographic KC, except for ocular tetrafoil between topographic KC and pretopographic KC and spherical aberration among all groups. The AUROCs for corneal total HOAs and corneal coma for pretopographic KC and control eyes were 0.781 (100% sensitivity and 47% specificity) and 0.735 (73% sensitivity and 73% specificity), respectively. Conclusion: Corneal total HOAs and corneal coma exhibited a potential ability to discriminate pretopographic KC from normal control eyes.