Vibrio vulnificus corneal ulcer: rapid resolution of a virulent pathogen.

PURPOSE: To describe a corneal ulcer due to Vibrio vulnificus that resolved rapidly with antibiotic therapy alone. METHOD: Case report and review of literature. RESULTS: This is the third reported case of corneal ulcer due to V. vulnificus. All followed trauma sustained during oyster shucking. Both prior cases required invasive therapy to achieve a cure. Our case responded rapidly to hourly treatment with ciprofloxacin, Neosporin, and fortified vancomycin. CONCLUSION: V. vulnificus is a virulent pathogen that can infect the cornea after shellfish injury to the eye. Clinical suspicion and early therapy with appropriate antibiotics can lead to an excellent outcome.

The value of routine donor corneal rim cultures in penetrating keratoplasty.

OBJECTIVE: To investigate the value of donor corneal rim cultures performed routinely at the time of penetrating keratoplasty. DESIGN: Retrospective review of Mayo Clinic medical records for all corneal transplantations for which donor rim cultures have been performed. MAIN OUTCOME MEASURES: Frequency of positive cultures, occurrence of endophthalmitis within 2 months of undergoing surgery, action taken in response to the culture results, and costs of cultures. RESULTS: Donor rim culture results were available for 1078 of 1083 consecutive transplantations performed from 1981 to 1995. Three cases of endophthalmitis (0.28%) and 1 suture abscess occurred. Rim cultures were negative in all of these cases. Action was documented in response to positive cultures in 17 cases (8.1%). The estimated average cost of routine rim cultures in 1994 was $137 per donor cornea. Bacterial or fungal cultures were positive in 209 (19.4%) cases. Two microorganisms were cultured simultaneously in 17 cases (1.6%) and 3 in 2 cases (0.2%). Staphylococcus coagulase-negative (130 cases [12.1%]), and Streptococcus species, viridans group (23 cases [2.1%]), were the most common isolates. Fifty-two (62.7%) of 83 coagulase-negative Staphylococcus species isolates tested were resistant to gentamicin. There were more positive cultures from corneas stored in Optisol (37/183 [20%]) than in Optisol GS (16/144 [11%]) (P = .03). Fewer cultures were positive from live donors (9/93 [10%]) compared with cadaveric donors (181/ 909 [20%]) (P = .02). Positive cultures were more frequent for corneas excised in situ (39/125 [31.2%]) than for those enucleated (152/851 [17.9%]) (P < .001). CONCLUSIONS: Despite differences in rates of positive donor rim cultures with different harvesting and storage techniques, for our practice, routine donor corneal rim cultures had no predictive value for infective complications of penetrating keratoplasty and, therefore, added an unnecessary expense to the management of our patients.

Corneal transplantation.

Corneal transplantation is a highly successful procedure for restoring sight in patients with corneal disease. The most common indication for transplantation is corneal edema following cataract extraction. A common problem following corneal transplantation is astigmatism, which often requires thick lenses for correction. The excimer laser holds promise for correcting postoperative astigmatism but is not yet in wide use. Rejection is a life-long risk and is most likely to occur during the first year. Topical corticosteroids are commonly used to decrease this risk. Frank corneal rejection must be recognized early and treated with intensive topical therapy.

Corneal hydration control in diabetes mellitus.

PURPOSE: To assess the effects of diabetes mellitus on corneal structure and function. METHODS: The authors measured endothelial permeability to fluorescein and corneal deswelling for 7.5 hours after 2 hours of hypoxic contact lens wear in 20 patients with diabetes who had nonproliferative retinopathy and 21 age-matched control subjects. Central corneal endothelial photographs were also taken. Corneal deswelling rates, expressed as percent recovery per hour (PRPH), and open eye steady state (OESS) thickness were estimated by nonlinear regression techniques. RESULTS: The OESS thickness was greater in patients with diabetes than in controls (562 +/- 35 microns versus 539 +/- 24 microns, P = 0.02). During hypoxia, the diabetic corneas swelled less (7.7% +/- 1.8% versus 9.9% +/- 1.6%, P < 0.001) and had less endothelial permeability (3.55 +/- 0.83 x 10(-4) cm/min versus 4.14 +/- 0.68 x 10(-4) cm/min, P = 0.02) than the controls. During normoxia after contact lens removal, however, diabetic and control corneas had similar deswelling rates and permeabilities. Corneal autofluorescence was increased in the patients with diabetes (8.1 +/- 3.1 versus 6.0 +/- 1.9 ng/ml fluorescein equivalents, P = .005). The endothelial cells of the two groups were morphologically similar. Within the group with diabetes, however, those with moderate nonproliferative retinopathy had larger coefficients of variation of cell area and smaller percentages of hexagonal cells than those with mild nonproliferative retinopathy. CONCLUSIONS: Although the diabetic corneas were thicker and more autofluorescent than control corneas, during hypoxia they swelled less and had decreased endothelial permeability. During normoxia, however, no difference was found in endothelial permeability or deswelling rate. The effects of diabetes on endothelial cell morphologic features appear to be related to the severity of the diabetes.