chondroitin-sulfates and Candidiasis

Fungal infections in lamellar keratoplasty are a growing concern. Optisol-GS does not contain an antifungal agent and supplementation with 0.255 μg/mL Amphotericin B (AmpB) has been considered. This study tested the ability of 0.255 μg/mL AmpB in Optisol-GS to eliminate yeast contamination of corneal tissue.. Three isolates of Candida albicans, 1 of Candida parapsilosis, and 1 of Candida glabrata were tested in Optisol with and without AmpB. Corneoscleral rims stored at -80°C were thawed and placed in 10 multiwell plates (4 per plate). The rims were inoculated with 4 respective loads of yeast: 0, 10, 10, and 10 colony-forming units in 2 sets of 5 for 5 yeasts. One set was filled with Optisol plus AmpB and the other with Optisol only. All 10 plates were incubated at cold storage (2°C-8°C) for 48 hours. After 48 hours, all corneal rims were placed into 10 mL of yeast extract peptone dextrose medium; a swab culture of each well was plated onto Sabouraud plates; and all plates with the remaining Optisol were incubated at 30°C. Yeast growth was monitored for 10 days. Minimum inhibitory concentration and minimum fungicidal concentration were determined.. All corneoscleral specimens were positive regardless of fungal load or presence of AmpB. All controls remained negative. Minimum inhibitory concentrations and minimum fungicidal concentrations were equivalent and ranged between 0.5 and 2.0 μg/mL.. AmpB at a concentration of 0.255 μg/mL in Optisol-GS at cold storage (2°C-8°C) over 48 hours did not eliminate yeast from corneal tissue.

Topics: Amphotericin B; Antifungal Agents; Candida; Candidiasis; Chondroitin Sulfates; Complex Mixtures; Cornea; Dextrans; Eye Banks; Eye Infections, Fungal; Gentamicins; Humans; Organ Preservation; Organ Preservation Solutions

Optisol-GS, the most common corneal storage medium in the United States, contains antibacterial but no antifungal supplementation. Most postkeratoplasty endophthalmitis and keratitis cases are now of a fungal origin.. To assess the efficacy and safety of voriconazole and amphotericin B in reducing Candida species contamination of Optisol-GS under normal storage conditions.. In vitro laboratory study using 15 pairs of research-grade donor corneas and 20-mL vials of Optisol-GS.. Twenty vials of Optisol-GS were supplemented with either voriconazole at 1×, 10×, 25×, or 50× minimum inhibitory concentration (MIC) or amphotericin B at 0.25×, 0.5×, 1×, or 10× MIC. Known concentrations of Candida albicans and Candida glabrata were each added to a set of vials. Safety studies were performed by separating 15 pairs of donor corneas into unsupplemented Optisol-GS or Optisol-GS plus an antifungal.. Efficacy outcomes were viable fungal colony counts determined from samples taken on days 2, 7, and 14 immediately after removal from refrigeration and after warming to room temperature for 2 hours. Safety outcomes included percentage of intact epithelium and endothelial cell density on days 0, 7, and 14, as well as percentage of nonviable endothelial cells by vital dye staining on day 14.. Growth of C albicans and C glabrata was observed in all voriconazole-supplemented vials. In contrast, there was no growth of either organism in amphotericin B-supplemented vials, except at 0.25× and 0.5× MIC on day 2, when viable counts of C glabrata were reduced by 99% and 96%, respectively. Compared with paired controls, with the exception of Optisol-GS plus amphotericin B at 10× MIC, donor corneas in supplemented Optisol-GS appeared to have no difference in endothelial cell density reduction, percentage of intact epithelium, or percentage of nonviable endothelial cells.. The addition of amphotericin B to Optisol-GS may significantly improve activity against contamination with Candida species, the primary cause of fungal infection after corneal transplantation. This study found significant endothelial toxic effects at the maximal concentration of amphotericin B.

Topics: Amphotericin B; Antifungal Agents; Candida albicans; Candida glabrata; Candidiasis; Cell Count; Chondroitin Sulfates; Colony Count, Microbial; Complex Mixtures; Cornea; Culture Media, Serum-Free; Dextrans; Drug Combinations; Drug Contamination; Endothelium, Corneal; Gentamicins; Humans; Microbial Sensitivity Tests; Organ Preservation; Organ Preservation Solutions; Pyrimidines; Tissue Donors; Treatment Outcome; Triazoles; Voriconazole

Topics: Antifungal Agents; Candidiasis; Chondroitin Sulfates; Cornea; Dextrans; Drug Contamination; Gentamicins; Humans; Organ Preservation Solutions

Topics: Antifungal Agents; Candidiasis; Chondroitin Sulfates; Cornea; Dextrans; Drug Contamination; Gentamicins; Humans; Organ Preservation Solutions

To construct a suitable ex vivo model for the research of molecular mechanisms and the pharmacological screening of fungal adherence on the corneal surface.. Mouse eyes were divided into three groups as follows: a control group with normal corneal epithelium, a group with corneal epithelium that was needle-scarified, and a group with corneal epithelium that was completely debrided. All 96 corneas were placed in organ culture and inoculated with 5 μl spore suspensions of Candida albicans at 10⁹, 10⁸, or 10⁷ colony-forming units (CFU)/ml and incubated for 0, 30, 60, or 120 min. The corneas were homogenated and diluted for quantification by counting the CFU. The effects of amphotericin B or chondroitin sulfate on the adherence of the fungal spores were evaluated with the ex vivo organ culture model and were also compared with the human corneal epithelium monolayer model in vitro.. Compared with the normal corneas with intact epithelium, the corneas with scarified and debrided epithelium adhered more spores for above two and four folds. The spore adhesion on the corneal surface was in an inoculation concentration- and incubation time-dependent manner. Moreover, both amphotericin B and chondroitin sulfate inhibited the adhesion of C. albicans spores on the corneal surface, but the inhibitory rates were different between the ex vivo corneal organ culture model and the in vitro corneal epithelium monolayer model.. The corneal organ culture was a suitable ex vivo model for the research of fungal adhesion mechanisms and drug screening.

Topics: Amphotericin B; Animals; Bacterial Adhesion; Candida albicans; Candidiasis; Chondroitin Sulfates; Colony Count, Microbial; Cornea; Corneal Injuries; Corneal Ulcer; Disease Models, Animal; Eye Infections, Fungal; Mice; Mice, Inbred BALB C; Organ Culture Techniques; Time Factors

This retrospective study of 549 corneo-scleral rim cultures shows that gentamicin, used in MK and K-Sol medium storage at 4 degrees C, has decreased donor contamination from 43% in whole-globe storage to 13%, but failed to eliminate coagulase negative staphylococci (37%), streptococci (28%) and fungi (28%). Donor-to-host transmitted staphylococcal and streptococcal endophthalmitis have been reported previously. We present the first documented case of donor-to-recipient transmitted fungal endophthalmitis following corneal transplantation using corneas stored in MK or K-Sol solution at 4 degrees C; Candida albicans was isolated. Recommendations are made to assess critically the true incidence of donor fungal contamination and the necessity of adding anti-mycotic agents to preservation medium for 4 degrees C storage. In the absence of ideal antimicrobial cover for corneal preservation solutions, stringent prophylactic measures to reduce contamination and continued monitoring of corneo-scleral rim cultures are warranted, if the poor visual consequences of donor-to-host transmitted endophthalmitis are to be avoided.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Candidiasis; Child; Child, Preschool; Chondroitin Sulfates; Corneal Transplantation; Endophthalmitis; Gentamicins; HEPES; Humans; Infant; Infant, Newborn; Male; Middle Aged; Mycoses; Organ Preservation; Postoperative Complications; Retrospective Studies; Staphylococcal Infections; Streptococcal Infections