Fusarium keratitis: genotyping, in vitro susceptibility and clinical outcomes.

PURPOSE: To determine differences in the clinical characteristics and antifungal susceptibility patterns among molecularly characterized ocular Fusarium sp isolates. METHODS: Fifty-eight isolates of Fusarium sp obtained from 52 eyes of 52 patients were retrieved from the Ocular Microbiology Laboratory of the Bascom Palmer Eye Institute and grown in pure culture. These isolates were characterized based on DNA sequence analysis of the ITS1/2 and ribosomal deoxyribonucleic acid regions. Antifungal susceptibilities were determined for each isolate using broth microdilution methods, and the corresponding medical records were reviewed to determine the clinical outcomes. RESULTS: Fusarium solani isolates had significantly higher values of minimum inhibitory concentration for 90% isolates (MIC90) with voriconazole than F. non-solani organisms (16 and 4 µg/mL, respectively). Isolates of F. solani also exhibited a significantly longer time to cure (65 vs. 40.5 days), a worse follow-up best-corrected visual acuity (20/118 vs. 20/36), and an increased need for urgent surgical management (7 vs. 0 penetrating keratoplasties) when compared with those of F. non-solani. CONCLUSIONS: This is the first report to examine the correlation between ocular genotyped Fusarium sp and clinical outcomes. It supports the overall worse prognosis of F. solani versus F. non-solani isolates, including higher voriconazole resistance by the former. The clinical implementation of molecular-based diagnostics and antifungal efficacy testing may yield important prognostic and therapeutic information that could improve the management of fungal ocular infections.

Interface blood after descemet stripping automated endothelial keratoplasty.

The authors report a case of a Descemet stripping automated endothelial keratoplasty that was complicated by intraoperative bleeding from the iridotomy site. Slit-lamp examination on postoperative day 1 revealed significant amount of retained blood at the donor-recipient interface and a best-corrected visual acuity (BCVA) of 20/400. The patient was managed with periodic observation and a topical fluoroquinolone and 1% prednisolone. By postoperative month 8, the interface had cleared, and the BCVA improved to 20/50. The patient remained with a clear cornea and stable BCVA of 20/50 at her most recent 1-year postoperative follow-up examination. Performing an intraoperative peripheral iridotomy to reduce the risk of air-associated pupillary block introduces the risk of its inherent complications, including intraoperative bleeding, retained blood cells at the interface, and delayed visual recovery. In this case, periodic observation and conservative management with topical steroids resulted in the resolution of the interface debris, associated keratitis, and improved postoperative visual acuity.

Etiologic diagnosis of corneal ulceration at a tertiary eye center in Kathmandu, Nepal.

PURPOSE: To determine the etiologic diagnosis of infectious corneal ulcers at Tilganga Institute of Ophthalmology, a tertiary teaching hospital in Kathmandu Nepal, from 2006-2009. METHODS: This study involved a review of all microbiology records at Tilganga Institute of Ophthalmology from August 2006 through July 2009. Microbiologic records from the corneal scrapings of all patients suspected of having infectious corneal ulcers were included. RESULTS: Corneal scrapings were obtained from 468 patients. The average patient age was 52 years, and 55% of the affected cases were males. Microorganisms were grown from 185 of the corneal scrapings (40%). Pure bacterial cultures were obtained from 72 patients (39%), and pure fungal cultures were obtained from 113 patients (61%). Gram stain was 75% sensitive (95% confidence interval, 0.632-0.841) in identifying bacterial infection, whereas KOH prep was 80.5% sensitive (95% confidence interval, 0.718-0.871) in identifying fungal organisms. Of 72 bacterial isolates, 50 isolates (69%) were Streptococcus pneumoniae, the most common organism isolated in this study. Of 113 fungal isolates, 40 of isolates (35%) were identified as Aspergillus sp. CONCLUSIONS: Fungal organisms (61%) are the most common cause of infectious keratitis in this patient population. Of all organisms, S. pneumoniae was the most common organism identified. Smear microscopy is reliable in rapidly determining the etiology of the corneal infection and can be used to help guide initial therapy in this setting.

The use of glycerol-preserved corneas in the developing world.

Corneal opacity is the third leading cause of blindness in the developing world and encompasses a wide variety of infectious, inflammatory and degenerative eye diseases. Most caes of corneal blindness are treatable with partial or full-thickness keratoplasty, provided adequate corneal tissue and surgical skill is available. However, access to sightrestoring keratoplasty in developing countries is limited by the lack of developed eye banking networks and a critical shortage of tissue suitable for transplantation. Beyond the developed world, corneal transplantation using fresh corneal tissue (FCT) is further hindered by unreliable storage and transportation facilities, unorganized distribution networks, the cost-prohibitive nature of imported tissue, unreliable compliance with medications and follow-up instructions and inadequate health and education services. Glycerol-preserved corneas overcome many of these limitations inherent to the use of FCT. As surgical innovation in lamellar corneal surgery expands the potential use of acellular corneal tissue, long-term preservation techniques are being revisited as a way to increase availability of corneal tissue to corneal surgeons throughout the developing world. Herein, we discuss the advantages of using and the applications for glycerol-preserved corneal tissue throughout the developing world.

Utility of molecular sequence analysis of the ITS rRNA region for identification of Fusarium spp. from ocular sources.

PURPOSE: Fungal ocular infections cause significant ocular morbidity, particularly when diagnosis and treatment are delayed. Accurate morphologic identification of Fusarium spp. beyond the genus is time-consuming and insensitive. It was the purpose of this study to examine the usefulness of the nuclear ribosomal RNA (rRNA) internal transcribed spacer regions (ITS1 and -2) to detect and differentiate Fusarium spp. responsible for ocular infections. METHODS: Fifty-eight archived isolates from ocular sources of 52 patients diagnosed with Fusarium keratitis at the Bascom Palmer Eye Institute (Miami, FL) from April 2000 to May 2007 were analyzed. The archived samples, which were initially classified according to morphologic characteristics, were analyzed by DNA sequence data generated from the ITS regions of the rRNA genes. RESULTS: Fifteen distinct sequences were identified among the 58 isolates. Sequence analysis identified the isolates as Fusarium solani (75%), F. oxysporum (16%), F. incarnatum-equiseti (5%), F. dimerum (2%), and one Fusarium sp. (2%) that was not classified within any species complex. Species identification based on sequence data correlated well with the morphologic classification when performed by a mycology reference laboratory, but a higher rate of mismatch was observed based on identification by a nonreference laboratory. CONCLUSIONS: Most of the isolates of Fusarium ocular infections belong to the F. solani or F. oxysporum species complexes. Morphologic classification at the species level yielded inconsistent results at a general microbiology laboratory. In contrast, the sequence variation within the ITS region allowed reliable and faster discrimination of the isolates at both the genus and species level.

Effects of a prostaglandin DP receptor agonist, AL-6598, on aqueous humor dynamics in a nonhuman primate model of glaucoma.

This study examines, in 11 cynomolgus monkeys with unilateral laser-induced glaucoma, the ocular hypotensive mechanism of action of AL-6598, partial agonist at the DP and EP prostanoid receptors. In a crossover fashion, both eyes of each monkey were dosed twice daily with 25 microL of either AL-6598 0.01% or vehicle for 2 days and on the morning of the 3rd day. Measurements were made on day 3 of each treatment. Alternative treatments were separated by at least 2 weeks. Intraocular pressures (IOPs) were measured by pneumatonometry and aqueous flow and outflow facility by fluorophotometry. Uveoscleral outflow was calculated mathematically. In the normotensive eyes, compared to vehicle treatment, AL-6598 decreased IOP from 22.5 +/- 0.7 to 18.7 +/- 0.9 mmHg (P = 0.006), increased uveoscleral outflow from 0.47 +/- 0.17 to 1.22 +/- 0.17 microL/min (P = 0.03), and increased aqueous flow from 1.49 +/- 0.10 to 1.93 +/- 0.13 microL/min (P = 0.01). No measurement in AL-6598-treated hypertensive eyes was significantly different from vehicle treatment. It is concluded that AL-6598 reduces IOP by increasing uveoscleral outflow in normotensive eyes of ketamine-sedated monkeys, despite an increase in aqueous flow. This effect is different from that of PGD(2), which decreases aqueous flow, and of the selective DP receptor agonist, BW245C, which increases both outflow facility and uveoscleral outflow in addition to decreasing aqueous flow.

Implantation of verisyse phakic intraocular lens to correct myopic refractive error after penetrating keratoplasty in pseudophakic eyes.

PURPOSE: We report 2 cases in which a Verisyse phakic intraocular lens (PIOL) was used to successfully treat high myopia after penetrating keratoplasty (PK) in pseudophakic patients. METHODS: Case 1 involved a 69-year-old pseudophakic man with a manifest refraction (MR) of -6.50 + 1.75 x 048 and a best spectacle corrected visual acuity (BSCVA) of 20/40 approximately 16 months after PK in the right eye. Case 2 was a 78-year-old pseudophakic man who had an MR of -9.00 + 5.75 x 132 with a BSCVA of 20/100 approximately 24 months after PK in the left eye. RESULTS: In case 1, 10 months after Verisyse PIOL implantation, the MR was pl +2.00 x 135 with a BSCVA of 20/30. Endothelial cell density (ECD) in this patient decreased from 1926.1 to 815.3 cells/mm over 17 months. In case 2, 24 months after Verisyse PIOL implantation, the MR was -3.25 + 3.50 x 105 with a BSCVA of 20/60. ECD in this patient decreased from 2108.4 to 753.8 cells/mm in 30 months. CONCLUSION: The Verisyse PIOL may provide an alternative method to correct high myopia for anisometropia in pseudophakic patients after PK. In this report, PIOL implantation was associated with a decrease in ECD. Further studies are required to determine the long-term effects and ultimate safety of PIOL placement on the integrity of the cornea endothelium after corneal transplant in pseudophakic patients.

Laser in situ keratomileusis in patients with corneal guttata and family history of Fuchs' endothelial dystrophy.

PURPOSE: To report 1-year results of laser in situ keratomileusis (LASIK) in 7 eyes with corneal endothelial guttata and a family history of Fuchs' endothelial dystrophy. SETTING: John Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. METHODS: A retrospective chart review was performed of 4 patients (7 eyes) who had trace to 1+endothelial guttata and a family history of Fuchs dystrophy and then had uneventful LASIK for the correction of myopia and myopic astigmatism. Preoperative and postoperative measurements included uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), corneal pachymetry, endothelial cell density (ECD), manifest refraction, and spherical equivalent. The changes in ECD, pachymetry, and spherical equivalent after LASIK were subjected to statistical analysis using a paired Student t test to determine significance. RESULTS: Transient corneal edema was noted in the early postoperative period in 3 eyes of 2 patients. At 1 year, 6 of the 7 (86%) eyes had lost > or =2 lines of BSCVA. A statistically significant decrease in ECD of 12.4% +/- 2.7% was observed at 1 year compared with baseline (P < .001). An increase in corneal thickness (P = .006) and a statistically significant myopic shift in spherical equivalent (P = .017) was also noted at 1 year compared with 3 months. CONCLUSIONS: Patients with mild corneal guttata and a family history of Fuchs' dystrophy are prone to transient corneal edema, loss of BSCVA, endothelial cell loss, and myopic regression after uneventful LASIK for correction of myopia and myopic astigmatism.