Report of the Eye Bank Association of America medical advisory board subcommittee on fungal infection after corneal transplantation

Fungal infection after keratoplasty and the role of antifungal supplementation to storage solution: a review

Fungal infection after corneal transplantation is a rare, yet potentially devastating, postoperative complication and has become a growing concern for the transplant surgeon and eye banking community. The Eye Bank Association of America (EBAA) has reported an increasing trend in the rate of postkeratoplasty fungal infections and a reversal in the previously documented predominance of bacterial over fungal infections. Additionally, several studies have confirmed a high correlation between positive corneoscleral donor rim fungal cultures and postoperative infections. Optisol GS (Bausch & Lomb, Irvine, California, USA), the most extensively used corneal storage solution in US eye banks, does not currently contain any antifungal supplementation. Although large randomised control trials evaluating the efficacy and safety of routine antifungal supplementation to corneal storage solution are lacking, several investigative studies have assessed the role of antifungal agents in reducing fungal contamination of donor corneas without causing undue corneal toxicity. This review will present the current epidemiology of postkeratoplasty fungal infections and evidence for obtaining routine fungal rim cultures and antifungal supplementation of storage solution.

[Fungal keratitis after penetrating keratoplasty]

The article presents a case of fungal keratitis after penetrating keratoplasty (PKP). A 35-years old patient had previously undergone surgical removal of an intraocular foreign body and developed chronic keratouveitis and epithelial-endothelial corneal dystrophy. PKP and early postoperative period were uneventful. The patient was frequently monitored with anterior segment photos. Two weeks later, fungal keratitis occurred on the edge of the donor flap. Direct microscopic evaluation revealed fungus spores and filaments, but growth of fungi in culture was negative. Instillation of steroids and antibiotics was discontinued, specific therapy included fluconazole and amphotericin B. Despite the ongoing treatment, keratitis has repeatedly recurred, and infiltrates were scraped. Topical and systemic voriconazole was administered instead of fluconazole in combination with regular scarification. After 3 weeks of treatment with voriconazole, stable corneal epithelialization was achieved and the cornea has restored its transparency. During 1.5 years of the follow-up, keratitis did not reccur; sutures were removed, corrected visual acuity increased to 1.0. Patients who had undergone PKP are at risk of developing fungal keratitis. Frequent monitoring of such patients contributes to early diagnosis of infectious complications. In the absence of officinal antifungal eye drops, specialist has to supply the patient with ex tempore antimycotic agents and change the treatment according to its effectiveness in each specific case.

Endophthalmitis Rates and Clinical Outcomes Following Penetrating and Endothelial Keratoplasty

PURPOSE

To evaluate endophthalmitis rates after penetrating keratoplasty (PK) and endothelial keratoplasty (EK) and to compare clinical outcomes.

DESIGN

Retrospective cohort study.

METHODS

The medical and billing records of several large academic private practices in Philadelphia, PA were electronically queried for all surgical visits during which a PK or EK was performed between April 1, 2012 and August 31, 2018. Demographic information and transplant characteristics were recorded for each patient and office visit. An additional query was performed to identify all cases of endophthalmitis based on diagnosis and procedure billing codes. Charts of patients with endophthalmitis were individually reviewed, and information was collected on triggering factors, clinical evaluation at presentation, management, culture data, visual outcomes, and graft survival rates. The main outcome measure was incidence of presumed infectious endophthalmitis following PK or EK.

RESULTS

During the study period, 1676 PKs and 2292 EKs for 3069 patients were performed. The mean age of patients in this transplant cohort was 66.4 (± 17.5) years and 54.6% of patients were women. Sixteen cases of endophthalmitis occurred during the study period; 12 cases of endophthalmitis occurred after PK and 4 cases occurred after EK. The rate of endophthalmitis after EK (4 of 2292; 0.2%) was significantly lower than that after PK (12 of 1676; 0.7%) (P = .01). In addition, the odds of developing endophthalmitis after PK or EK performed in conjunction with anterior vitrectomy were significantly higher than after either PK or EK alone (odds ratio 8.66; 95% confidence interval 2.98-25.18; P < .001). Visual acuity outcomes were poorer after PK-related endophthalmitis than EK-associated cases (P = .01). The rate of graft failure at final follow-up was significantly higher in post-PK endophthalmitis (P = .02).

CONCLUSIONS

In this large cohort of patients undergoing either PK or EK, rates of endophthalmitis were low for both procedures and significantly lower for EK compared with PK. Eyes with endophthalmitis after PK had poorer visual acuity outcomes and graft prognosis compared with those with endophthalmitis after EK.

Effect of Optisol Supplementation With 0.255 μg/mL Amphotericin B on Elimination of Yeast at 5°C

PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Functional Protein-Based Bioinspired Nanomaterials: From Coupled Proteins, Synthetic Approaches, Nanostructures to Applications

Protein-based bioinspired nanomaterials (PBNs) combines the advantage of the size, shape, and surface chemistry of nanomaterials, the morphology and functions of natural materials, and the physical and chemical properties of various proteins. Recently, there are many exciting developments on biomimetic nanomaterials using proteins for different applications including, tissue engineering, drug delivery, diagnosis and therapy, smart materials and structures, and water collection and separation. Protein-based biomaterials with high biocompatibility and biodegradability could be modified to obtain the healing effects of natural organisms after injury by mimicking the extracellular matrix. For cancer and other diseases that are difficult to cure now, new therapeutic methods involving different kinds of biomaterials are studied. The nanomaterials with surface modification, which can achieve high drug loading, can be used as drug carriers to enhance target and trigger deliveries. For environment protection and the sustainability of the world, protein-based nanomaterials are also applied for water treatment. A wide range of contaminants from natural water source, such as organic dyes, oil substances, and multiple heavy ions, could be absorbed by protein-based nanomaterials. This review summarizes the formation and application of functional PBNs, and the details of their nanostructures, the proteins involved, and the synthetic approaches are addressed.

Next-generation sequencing for the detection of microorganisms present in human donor corneal preservation medium

Objective

To detect the presence of microorganisms in the storage media of human donor corneas using next-generation sequencing method.

Methods

Seven samples from organ culture (OC) group (Cornea Max, Eurobio, Les Ulis, France) with one control (sterile media without any cornea) and seven samples from hypothermic storage group (Cornea Cold, Eurobio) with one control were used for this study. The corneas were placed in the respective storage media for 14 days before collecting the samples. Storage media (2 mL) from each sample were collected in RNAase-free tubes and shipped for ribosomal RNA sequencing of 16 S and 18 S. Simultaneously, another 1 mL of media sample was used for conventional diagnostic method (CDM) using Bactec instruments.

Results

In both, OC and hypothermic storage and control samples, the most abundant genera were Pseudomonas, Comamonas, Stenotrophomonas, Alcanivorax, Brevundimonas and Nitrobacter. Acidovorax, Acetobacter and Hydrogenophilus were detected mostly in the hypothermic storage group. The most abundant fungal pathogen detected belonged to the genus Malassezia, which was found in both the storage conditions. CDM was negative for microorganisms in all the samples.

Conclusion

Metagenomics provides full taxonomic profiling of the detected genomic material of the organisms and thus has the potential to deliver a much wider microbiological diagnostic approach than CDM. The costs and turn-around time need to be reduced, and; the detection of viable organisms would help this technology to be introduced into routine clinical practice.

Reports of Post-keratoplasty Infections for Eye Bank-prepared and Non-Eye Bank-prepared Corneas: 12 Years of Data From a Single Eye Bank

PURPOSE

To examine postoperative reports of infection rates for eye bank-prepared and non-eye bank-prepared corneas from January 1, 2006 to December 31, 2017, from a single eye bank.

METHOD

A retrospective review of reported fungal and bacterial infections with corneal transplant surgeries using corneas distributed by our eye bank was conducted. The reported number of infections for corneas that underwent eye bank preparation (pre-cut and pre-stripped corneas) and for those distributed without eye bank preparation was quantified. The potential association between infection rates in tissue prepared by the eye bank and those in corneas that had no additional eye bank processing was also examined.

RESULTS

Four of 17,035 corneas distributed during the study period were associated with fungal infections (1 eye bank-prepared and 3 non-eye bank-prepared corneas) and were attributed to the tissue after investigation by eye bank medical directors. There was no ascending trend of infections reported with eye bank-prepared corneas in the first 3 years (2 of 1054 corneas, 0.19%) compared with that in the last 3 years of the study period (6 of 3500 corneas, 0.17%; P = 0.901) when the eye bank distributed 3 times more prepared corneas than non-eye bank-prepared corneas. A significant increase in the numbers of reported infections for non-eye bank-prepared corneas was observed between these 3-year intervals (0.1% in the first 3 years to 1.58% in the last 3 years; P = 0.001).

CONCLUSIONS

Reports of infections remained low despite increased use of eye bank-prepared tissue. These results suggest that factors other than eye bank tissue preparation should be considered when investigating potential sources of pathogen contamination in donor corneas.

Microbial Analysis of Donor Corneoscleral Rims and Storage Media

Purpose: We aim to investigate bacterial and fungal cultures of hypothermic donor corneal storage media (Optisol-GS) and donor rims. Methods: All corneal transplants performed from January 1, 2015 to June 30, 2016 by a single surgeon at a single facility were retrospectively reviewed. Aerobic, anaerobic, and fungal cultures were routinely obtained from all donor rims and cornea storage media. Culture results and clinical courses were recorded. Results: Eighty-four corneal transplants were performed. Five of 84 grafts (5.95%) had positive bacteria donor rim cultures. Fungal donor rim cultures were positive in 5/84 grafts (5.95%) of which two grew Candida spp. Storage media bacterial cultures were positive in 2/84 (2.4%) cultures. Storage media fungal cultures were positive in 1/84 (1.2%) cultures. No patients developed any evidence of clinical infection. Conclusions: Given the increasing rates of postkeratoplasty fungal infections, the identification of positive fungal cultures from donor rims and storage media warrants further evaluation of adding antifungals to storage media.

Fungal infection after endothelial keratoplasty: association with hypothermic corneal storage

PURPOSE

To compare the incidence of fungal infection after endothelial keratoplasty (EK) when donor tissue had been stored in hypothermic medium or organ culture.

METHODS

We describe the clinical features of 10 cases of fungal infection (keratitis or endophthalmitis) following EK identified at three European centres. Case definition was the culture of fungus or a positive PCR from the host cornea or anterior chamber after EK. A survey of the incidence of infection after EK was conducted by the European Eye Bank Association. The main outcome measure was the number of cases in which donor tissue had been stored in hypothermic medium compared with organ culture.

RESULTS

The 10 cases occurred between 2014 and 2017. All donor corneas had been stored in hypothermic medium sourced from three US eye banks. Three pairs of mate corneas caused infections in six recipients. Candida spp were identified from nine cases, with one isolate of Purpureocillium lilacinum. Data on 16 862 corneas supplied for EK were available from 16 European eye banks for the 5-year period from 2012. There were 17 reported cases of infection, of which 15 (88%) were fungal infections and 14 (82%) were Candida spp. Fungal infection was reported from 3 of 14 476 (0.02%) corneas supplied in organ culture compared with 12 of 2386 (0.50%) corneas supplied in hypothermic medium (p<0.0001). The incidence of infection after hypothermic storage was similar for material sourced from Europe (0.52%) or the USA (0.61%).

CONCLUSIONS

Infection after EK is strongly associated with Candida spp. The possible explanations for the higher incidence of infection when tissue is stored in hypothermic medium are discussed.

A presentation of culture-positive corneal donors and the effect on clinical outcomes

PURPOSE

Donor-to-host transmission of infectious agents is a rare but well-recognised complication of corneal transplantation and may carry a grave visual prognosis. In this case series, we describe the clinical features and risk factors of using culture-positive donor corneas for transplantation.

METHODS

Retrospective chart review of a series of patients who underwent either penetrating keratoplasty (PK) or Descemet's stripping automated endothelial keratoplasty (DSAEK) with positive microbiology cultivation during routine assessment of donor corneal tissue obtained at the time of surgery. Donor and recipient characteristics, tissue preparation and surgical parameters, clinical signs and outcomes were registered.

RESULTS

Eleven patients who received culture-positive corneal grafts were identified: six with Candida, three with Gram-positive bacteria and two with Gram-negative bacteria. Three patients developed clinical keratitis after routine DSAEK using corneas contaminated with Candida species. The median death-to-preservation time (DPT) of these three donor corneas was 18.08 (range 18.08 to 20.90) h, while in the remaining eight donors, it was 12.27 (range 9.32 to 20.47) h. Despite the initiation of antifungal treatment, all three cases required explantation of the graft and a subsequent re-DSAEK.

CONCLUSIONS

The use of donor corneas that are culture-positive for Candida carries a risk for developing postoperative keratitis and the risk may be higher in DSAEK. Unlike the cold storage technique employed for donor corneas described in this case series, organ culture technique requires microbiological screening and supplementation of an antifungal agent which may reduce the risk of donor-to-host transmission of fungal infection.

Fungal Interface Keratitis After Descemet Membrane Endothelial Keratoplasty

PURPOSE

To evaluate the incidence, clinical course, and management of fungal interface keratitis (IK) after Descemet membrane endothelial keratoplasty (DMEK).

METHODS

This is a single-center retrospective observational case series of 3950 eyes undergoing DMEK. Six eyes with fungal IK were detected and analyzed. Analysis included graft storage condition, incidence of fungal IK, identification of the pathogenic agent, topical/systemic and surgical treatment regimen, and best-corrected visual acuity.

RESULTS

Fungal IK after DMEK occurred in 6 of 3950 cases (0.15%). Corneal grafts were either stored in Optisol-GS (n = 4) or in organ culture (n = 2). In all cases, Candida species were isolated (Candida tropicalis, Candida albicans, Candida orthopsilosis, and Candida guilliermondii). Four eyes developed fungal IK during the early postoperative period (3-5 d) and 2 eyes later at 16 to 42 days after surgery. All patients received topical and systemic antifungal treatment and intracameral application of antifungal agents. In the case of an early infection, graft removal was performed in 3 of 4 patients. Late infections were eradicated without graft exchange. Recurrence of fungal infection was observed in 1 case after early IK and in both cases after late IK. Final visual acuity ranged from 20/200 to 20/20.

CONCLUSIONS

Fungal IK is a rare complication after DMEK. Based on our experience, we believe that treatment of early fungal IK with aggressive presentation should include both immediate graft exchange and intracameral application of voriconazole and amphotericin, in addition to topical and systemic antifungal treatment. Graft exchange seems not to be mandatory in late infections.

Interface infectious keratitis after anterior and posterior lamellar keratoplasty. Clinical features and treatment strategies. A review

Interface infectious keratitis (IIK) is a novel corneal infection that may develop after any type of lamellar keratoplasty. Onset of infection occurs in the virtual space between the graft and the host where it may remain localised until spreading with possible risk of endophthalmitis. A literature review identified 42 cases of IIK. Thirty-one of them occurred after endothelial keratoplasty and 12 after deep anterior lamellar keratoplasty. Fungi in the form of Candida species were the most common microorganisms involved, with donor to host transmission of infection documented in the majority of cases. Donor rim cultures were useful to address the infectious microorganisms within few days after surgery. Due to the sequestered site of infection, medical treatment, using both topical and systemic antimicrobials drugs, was ineffective on halting the progression of the infection. Injection of antifungals, right at the graft–host interface, was reported successful in some cases. Spreading of the infection with development of endophthalmitis occurred in five cases after Descemet stripping automated endothelial keratoplasty with severe sight loss in three cases. Early excisional penetrating keratoplasty showed to be the treatment with the highest therapeutic efficacy, lowest rate of complications and greater visual outcomes.

Incidence and Outcomes of Positive Donor Rim Cultures and Infections in the Cornea Preservation Time Study

PURPOSE

To assess donor rim culture results and outcomes of ocular infections in the Cornea Preservation Time Study (CPTS).

METHODS

Donor corneal rim cultures were optional. Donor characteristics were assessed for association with positive cultures using the Fisher exact test and Poisson regression analyses. Incidence rates of ocular infections were estimated, and 95% confidence intervals were calculated.

RESULTS

Cultures were performed in 784 (58.9%) of the 1330 cases. For the 0 to 7-day versus 8 to 14-day preservation time groups, respectively, positive fungal growth occurred in 10 of 397 (2.5%) versus 5 of 387 (1.3%) corneas (P = 0.30), whereas positive bacterial cultures occurred in 6 of 397 (1.5%) versus 4 of 387 (1.0%) corneas (P = 0.75). Surgeon-prepared tissue remained a significant risk for positive fungal cultures [relative risk (RR) of surgeon- versus eye-bank-prepared, 2.85; 95% CI (1.02-7.98)], whereas younger donors [RR per year of age, 0.96; 95% CI (0.93-1.00)] and accidental death donors [RR of accident versus disease, 3.71; 95% CI (1.36-10.13)] were at a greater risk for positive bacterial cultures. Fungal infection (Candida glabrata) developed in 1 (6.7%) of 15 recipients with a positive fungal culture, and no recipient infections occurred with positive bacterial culture. With one additional fungal keratitis (Candida albicans) and one bacterial endophthalmitis (E. coli) with no rim culture performed, a total of 2 of 1330 eyes (0.15%) developed fungal and 1/1330 eyes (0.08%) developed bacterial postkeratoplasty infections.

CONCLUSIONS

A longer preservation time was not associated with a higher rate of positive donor rim cultures. The overall rate of infection across the entire cohort was low.

Overview of Systemic Candida Infections in Hospital Settings and Report of Candida After DMEK Successfully Treated With Antifungals and Partial Graft Excision

PURPOSE

To report novel surgical and medical management of intraocular and corneal infection with Candida glabrata that manifested 3 months after Descemet membrane endothelial keratoplasty (DMEK) and to review demographic reasons for increasing fungal contamination of donor tissue.

METHODS

Demographics, donor rim cultures, diagnostic tests, management, clinical course, outcomes, and donor mate outcomes are reported for a fungal infection after DMEK.

RESULTS

The fungal infection was treated for 3 weeks with a combination of intracameral and intracorneal voriconazole and intracameral and topical amphotericin B (off-label use). After initial improvement, the infection appeared to spread to the posterior chamber and the cornea decompensated. Pars plana vitrectomy was performed, and the fungal plaque and underlying area of the graft (approximately 3 mm area) were excised with the vitrector. After surgical intervention, the voriconazole and amphotericin B injections were discontinued, and oral posaconazole was prescribed for 2 months (off-label use). This combination of surgical and medical management successfully cleared the infection. Surprisingly, corneal edema completely resolved, and central DMEK endothelial cell density was 2506 cells/mm 1 month after discontinuing the antifungal injections, which apparently caused reversible endothelial toxicity.

CONCLUSIONS

The incidence of nosocomial fungal infections, particularly non-albicans Candida, is increasing, as are the rates of positive fungal cultures from corneal donor tissue and postkeratoplasty fungal infections. Prospective studies are needed to assess the value of routine donor cultures, compare the safety and efficacy of various prophylactic treatments, and evaluate addition of antifungals to cold storage media.

Candida Endophthalmitis After Descemet Stripping Automated Endothelial Keratoplasty With Grafts From Both Eyes of a Donor With Possible Systemic Candidiasis

PURPOSE

To report 2 cases with late postoperative Candida albicans interface keratitis and endophthalmitis after Descemet stripping automated endothelial keratoplasty (DSAEK) with corneal grafts originating from a single donor with a history of presumed pulmonary candidiasis.

METHODS

Two patients underwent uncomplicated DSAEK by 2 corneal surgeons at different surgery centers but with tissue from the same donor and were referred to the Bascom Palmer Eye Institute with multifocal infiltrates at the graft-host cornea interface 6 to 8 weeks later, and anterior chamber cultures that were positive for the same genetic strain of C. albicans. Immediate explantation of DSAEK lenticules and daily intracameral and instrastromal voriconazole and amphotericin injections failed to control the infection. Thus, both patients underwent therapeutic penetrating keratoplasty with intraocular lens explantation, pars plana vitrectomy, and serial postoperative intraocular antifungal injection.

RESULTS

Both patients are doing well at 2 years postoperatively with best-corrected vision of 20/20 and 20/30+ with rigid gas permeable lenses. One patient required repeat optical penetrating keratoplasty and glaucoma tube implantation 1 year after the original surgery. Literature review reveals that donor lenticule explantation and intraocular antifungals are often inadequate to control fungal interface keratitis, and a therapeutic graft is commonly needed.

CONCLUSIONS

Interface fungal keratitis and endophthalmitis due to infected donor corneal tissue is difficult to treat, and both recipients of grafts originating from the same donor are at risk of developing this challenging condition.

Biofunctionalized Lysophosphatidic Acid/Silk Fibroin Film for Cornea Endothelial Cell Regeneration

Cornea endothelial cells (CEnCs) tissue engineering is a great challenge to repair diseased or damaged CEnCs and require an appropriate biomaterial to support cell proliferation and differentiation. Biomaterials for CEnCs tissue engineering require biocompatibility, tunable biodegradability, transparency, and suitable mechanical properties. Silk fibroin-based film (SF) is known to meet these factors, but construction of functionalized graft for bioengineering of cornea is still a challenge. Herein, lysophosphatidic acid (LPA) is used to maintain and increase the specific function of CEnCs. The LPA and SF composite film (LPA/SF) was fabricated in this study. Mechanical properties and in vitro studies were performed using a rabbit model to demonstrate the characters of LPA/SF. ATR-FTIR was characterized to identify chemical composition of the films. The morphological and physical properties were performed by SEM, AFM, transparency, and contact angle. Initial cell density and MTT were performed for adhesion and cell viability in the SF and LPA/SF film. Reverse transcription polymerase chain reactions (RT-PCR) and immunofluorescence were performed to examine gene and protein expression. The results showed that films were designed appropriately for CEnCs delivery. Compared to pristine SF, LPA/SF showed higher biocompatibility, cell viability, and expression of CEnCs specific genes and proteins. These indicate that LPA/SF, a new biomaterial, offers potential benefits for CEnCs tissue engineering for regeneration.

Reduction of Donor Cornea Exposure to Repeat Warming Cycles and Evaluation Times After Implementation of a Rapid Warming Protocol

PURPOSE

To compare tissue evaluation times and specular image quality before and after the implementation of rapid tissue warming at a single eye bank.

METHODS

This retrospective study compares the evaluation of 494 donor corneas. All corneas were stored in Optisol-GS. Group 1 contained 247 corneas evaluated immediately before implementation of a tissue incubator and tissue warming protocol. Group 2 contained 247 corneas evaluated immediately after implementation. Total evaluation times (including specular microscopy, optical coherence tomography for corneal thickness measurements, and 2 slit-lamp examinations) were calculated and compared. Representative specular images of donor corneas were rated and compared using a previously described scale by 2 masked readers.

RESULTS

Donor tissue characteristics were not significantly different between both groups (age, P = 0.87; sex, P = 0.93; endothelial cell densities, P = 0.47; and death-to-preservation times, P = 0.18). The mean total evaluation time for group 2 corneas was ∼3 hours, with 97% (201/208) of evaluations completed on the same day. In contrast, only 73% (164/225) of corneas from group 1 were completely evaluated in 1 day, and the mean evaluation time for those corneas was ∼4.25 hours (P < 0.01). Specular images of corneas from group 2 were rated 1 grade higher, on average, than those from group 1 (n = 247 in each group, P < 0.01). Furthermore, 71% of specular images from group 2 were categorized as "good" or "excellent" quality, whereas only 30% of corneas from group 1 received those ratings.

CONCLUSIONS

Rapid tissue warming cuts down on tissue evaluation time and reduces the time donor corneas are out of cold storage. Better specular images were obtained after implementation of the rapid warming protocol.

Post-keratoplasty Endophthalmitis by Multidrug-resistant Pseudomonas Aeruginosa With Positive Culture of the Contralateral Donor Cornea: A Case Report

PURPOSE

The aim of this paper is to present the case report of a patient developing endophthalmitis after penetrating keratoplasty caused by a multidrug-resistant Pseudomonas aeruginosa, detected only in the contralateral donor tissue.

CASE REPORT

A 77-year-old man underwent an uneventful penetrating keratoplasty with a preoperative culture-negative donor cornea; however, the fellow cornea grew multidrug-resistant Pseudomonas aeruginosa. The patient developed and was treated for endophthalmitis after penetrating keratoplasty, and aqueous and vitreous taps grew P. aeruginosa with antibiotic resistance identical to the isolate from the mate cornea. Sequence analysis of the 16S ribosomal gene from the two isolates and confirmation analyzing the sequence of P. aeruginosa heat shock protein gene (groES) were performed showing the same strain for both organisms.

CONCLUSION

This case report documents the presence of the same multidrug-resistant P. aeruginosa causing endophthalmitis after penetrating keratoplasty and in the contralateral donor tissue, suggesting that we must be cautious in deciding to transplant tissues with positive culture in the contralateral donor cornea.

Association Between Fungal Contamination and Eye Bank-Prepared Endothelial Keratoplasty Tissue: Temperature-Dependent Risk Factors and Antifungal Supplementation of Optisol-Gentamicin and Streptomycin

Importance

Fungal contamination and infection from donor tissues processed for endothelial keratoplasty is a growing concern, prompting analysis of donor tissues after processing.

Objective

To determine whether eyebank-processed endothelial keratoplasty tissue is at higher risk of contamination than unprocessed tissue and to model eyebank processing with regard to room temperature exposure on Candida growth in optisol-gentamicin and streptomycin (GS) with and without antifungal supplementation.

Design, Setting, and Participants

An examination of the 2013 Eversight Eyebank Study follow-up database for risk factors associated with post-keratoplasty infection identified an increased risk of positive fungal rim culture results in tissue processed for endothelial keratoplasty vs unprocessed tissue. Processing steps at room temperature were hypothesized as a potential risk factor for promotion of fungal growth between these 2 processes. Candida albicans, Candida glabrata, and Candida parapsilosis endophthalmitis isolates were each inoculated into optisol-GS and subjected to 2 different room temperature incubation regimens reflective of current corneal tissue handling protocols.

Main Outcomes and Measures

Eversight Eyebank Study outcomes and measures were follow-up inquiries from 6592 corneal transplants. Efficacy study outcomes and measures were fungal colony-forming units from inoculated vials of optisol-GS taken at 2 different processing temperatures.

Results

Donor rim culture results were 3 times more likely to be positive for fungi in endothelial keratoplasty-processed eyes (1.14%) than for other uses (0.37%) (difference, 0.77%; 95% CI, 0.17-.1.37) (P = .009). In vitro, increased room temperature incubation of optisol-GS increased growth of Candida species over time. The addition of caspofungin and voriconazole decreased growth of Candida in a species-dependent manner.

Conclusions and Relevance

Detectable Candida growth in donor rim cultures, associated with a higher rate of post keratoplasty infection, is seen in endothelial keratoplasty tissue vs other uses at the time of transplantation, likely owing in part to eyebank preparation processes extending the time of tissue warming. Reduced room temperature incubation and the addition of antifungal agents decreased growth of Candida species in optisol-GS and should be further explored to reduce the risk of infection.

Rapid Warming of Donor Corneas Is Safe and Improves Specular Image Quality

PURPOSE

To determine whether warming donor corneas to near-physiological temperatures can safely shorten warming times while providing high-quality specular images during tissue evaluation.

METHODS

Mated corneas were warmed at room temperature (RT) or at 35°C for 4 hours upon removal from cold storage. Specular images and endothelial cell densities were acquired and rated every hour. Additional mated corneas were subjected to 2 rounds of 4-hour incubation at either RT or 35°C. Endothelial cell loss (ECL) was quantified 14 days after the initial incubation using Calcein-acetoxymethyl (Calcein-AM) and FIJI trainable segmentation. Cultures inoculated with common ocular pathogens were subjected to 2 warming cycles at RT for 4 hours or 35°C for 2 hours. Colony counts were taken over the course of 2 weeks after inoculation.

RESULTS

Specular image quality ratings were consistently higher for corneas warmed at 35°C compared with those at RT. Image quality ratings for corneas warmed at 35°C for 1.5 hours were higher than corneas warmed at RT for 4 hours (P = 0.04). No differences in ECL were observed between the 2 warming conditions (RT = 13.1% ± 7.6% ECL, 35°C = 13.9% ± 6% ECL, P = 0.75). There was no difference in colony counts for pathogens tested between the 2 warming conditions.

CONCLUSIONS

Warming donor corneas to near-physiological temperatures for a short time can increase specular image quality while reducing the time tissues are unrefrigerated at eye banks. This method allows for more efficient specular imaging without inducing additional ECL or increasing pathogen growth.

First Reported Case of Donor Related Candida Endophthalmitis after Descemet Membrane Endothelial Keratoplasty

Purpose:

To report the first case of Candida donor to host transmission following descemet membrane endothelial keratoplasty (DMEK)

Methods:

A retrospective case report.

Results:

A patient underwent uneventful DMEK. Following surgery the donor rim was culture positive for Candida. The patient developed fungal endophthalmitis that was treated medically with multiple injections of voriconazole and amphotericin. Medical treatment was unable to clear the infection and removal of the donor material was required. Following removal the infection subsided.

Conclusion:

Candida interface keratitis and endophthalmitis can occur following DMEK and may be difficult to treat medically. Early removal of the donor material should be considered.

In Vivo Characteristics of Corneal Endothelium/Descemet Membrane Complex for the Diagnosis of Corneal Graft Rejection

PURPOSE

To evaluate the utility of endothelial/Descemet membrane complex (En/DM) characteristics in diagnosing corneal graft rejection.

DESIGN

Diagnostic reliability study.

METHODS

One hundred thirty-nine eyes (96 corneal grafts post penetrating keratoplasty or Descemet stripping automated endothelial keratoplasty: 40 clear, 23 actively rejecting, 24 rejected, and 9 nonimmunologic failed grafts; along with 43 age-matched control eyes) were imaged using high-definition optical coherence tomography. Images were used to describe En/DM and measure central corneal thickness (CCT) and central En/DM thickness (DMT). En/DM rejection index (DRI) was computed to detect the relative En/DM thickening to the entire cornea.

RESULTS

In actively rejecting grafts, DMT and DRI were significantly greater than controls and clear grafts (28, 17, and 17 μm and 1.5, 1 and 1, respectively; P < .001). Rejected grafts had the highest DMT and DRI compared to all groups (59 μm and 2.1; P < .001). DMT and DRI showed excellent accuracy, significantly better than that of CCT, in differentiating actively rejecting from clear grafts (100% and 96% sensitivity; 92.5% and 92.5% specificity), actively rejecting from rejected grafts (88% and 83% sensitivity; 91% and 83% specificity), and nonimmunologic failed from rejected grafts (100% and 100% sensitivity; 88% and 100% specificity). DMT correlated significantly with rejection severity (P < .001).

CONCLUSIONS

In corneal grafts, in vivo relative thickening of the En/DM is diagnostic of graft rejection as measured by DMT and DRI. These indices have excellent accuracy, sensitivity, and specificity in detecting graft immunologic status, superior to CCT. DMT is a quantitative index that correlates accurately with the severity of rejection.

Report of the Eye Bank Association of America Medical Review Subcommittee on Adverse Reactions Reported From 2007 to 2014

PURPOSE

To investigate the incidence of adverse reactions after corneal transplantation, reported to the Eye Bank Association of America.

METHODS

Incidence of adverse reactions from January 1, 2007, to December 31, 2014, was analyzed.

RESULTS

Of the 354,930 transplants performed in the United States, adverse reactions were reported in 494 cases (0.139%). Primary graft failure (PGF) predominated (n = 319; 0.09%) followed by endophthalmitis (n = 99; 0.028%) and keratitis (n = 66; 0.019%). The procedure type predominantly associated with PGF was endothelial keratoplasty (EK) in 56% (n = 180; 11 per 10,000 grafts), followed by penetrating keratoplasty (PK) in 42% (n = 135; 6.9 per 10,000 grafts). The procedure type predominantly associated with endophthalmitis and keratitis was EK in 63% (n = 104; 6.3 per 10,000 grafts) followed by PK in 34% (n = 56; 2.8 per 10,000 grafts), anterior lamellar keratoplasty in 1% (n = 2; 2.7 per 10,000 grafts), and keratoprosthesis in 1% (n = 2; 12.4 per 10,000 grafts). Although the incidence of PGF and endophthalmitis between PK and EK was noteworthy, the difference was not statistically significant (P = 0.098). Endophthalmitis-associated pathogens were isolated in 78% of cases: predominantly Candida species (65%), gram-positive organisms (33%), and gram-negative rods (2%). Keratitis-associated pathogens were isolated in 64% of cases: predominantly Candida species (81%), Herpes simplex virus (7%), gram-negative organisms (7%), and gram-positive organisms (5%).

CONCLUSIONS

PGF was the most commonly reported adverse reaction, disproportionately associated with EK. An increasingtrend in the rate of endophthalmitis and keratitis was observed, disproportionately associated with EK and Candida species.

A case of fungal keratitis and endophthalmitis post penetrating keratoplasty resulting from fungal contamination of the donor cornea

Purpose

Fungal infections post keratoplasty due to contamination of the donor corneal graft have become important issues that need to be addressed. Here we report a case of fungal keratitis and endophthalmitis post penetrating keratoplasty (PKP) due to fungal contamination of the donor corneal graft.

Observations

We present a 52-year-old male who underwent PKP with a donor corneal graft that was later found to be contaminated with fungus. At 4-weeks postoperative, infectious infiltrates suddenly appeared at the border between the host and donor corneal graft, and endophthalmitis concomitantly occurred. A culture of the remnant donor corneoscleral rims and the vitreous fluid obtained during vitreous surgery was found to be positive for Candida albicans. At 6-months post vitreous surgery and intensive anti-fungal medical treatment, both corneal infiltrates and vitreous opacity completely disappeared, and the patient's best-corrected visual acuity recovered to 20/40, with a transparent cornea.

Conclusions and importance

The findings of this case show that prompt intensive medical treatment and surgical intervention effectively saved the vision in a patient with fungal keratitis and endophthalmitis due to contamination of the donor corneal graft.

Systemic Fungal Infections in Donors for Corneal Transplantation

PURPOSE

To determine the prevalence of postkeratoplasty fungal infection when corneal tissue from donors with a recent medical history of oral thrush or respiratory, urine, wound, sputum, bronchial, tracheal, or throat culture positive for fungus is identified before recovery and after decontamination of the corneal tissue with 5% povidone-iodine flush to the donors' eyes during recovery.

METHODS

This is a prospective analysis of corneas from 42 donors with a documented medical history of fungus or positive fungal culture, which were recovered between January 2010 and November 2010. Standard aseptic swab of the donors' corneas before and after application of 5% povidone-iodine solution was performed. Culture results were analyzed in relationship to the donors' medical history and potential posttransplantation infections.

RESULTS

Eighty-four eyes from 42 patients were swabbed for cultures during the study period. Seven eyes (8.3%) were positive for fungal growth before treatment with 5% povidone-iodine, whereas there were no positive fungal cultures after treatment (P = 0.007). Fifty-four corneas from this study group were used for corneal transplantation. There were no cases of fungal infection in any postkeratoplasty eyes transplanted from this study group.

CONCLUSIONS

In this small study, the overall prevalence of fungal infections after corneal transplantation using corneal donor tissue from donors with a fungal-positive medical history is low. Corneal fungal contamination in donors with a history of fungal infection or a positive fungal culture can be significantly reduced with a 5% povidone-iodine flush.

Incidence and Outcomes of Positive Donor Corneoscleral Rim Fungal Cultures after Keratoplasty

PURPOSE

To determine the incidence of positive corneoscleral donor rim fungal cultures after keratoplasty and to report clinical outcomes of grafts with culture-positive donor rims.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Consecutive donor corneas and keratoplasty recipients at a single tertiary referral center over 20 years.

METHODS

Patient charts were reviewed to determine the incidence of positive donor rim fungal cultures and clinical outcomes of all grafts using contaminated tissue.

MAIN OUTCOME MEASURES

The primary outcome measures were positive donor rim fungal culture results and the development of postkeratoplasty fungal infection using corresponding corneal tissue. The secondary outcome measure was the impact of postoperative prophylaxis on donor tissue-associated infections.

RESULTS

A total of 3414 keratoplasty cases were included in the statistical analysis. Seventy-one cases (2.1%) were associated with a fungal culture-positive donor rim. Candida species were cultured in 40 cases (56.3%). There was a higher incidence of positive rim cultures over the last 5 years of the analytic period compared with the first 15 years (P = 0.018). Fungal keratitis developed in 4 cases (5.6%), and all patients required further surgical intervention to achieve cure. There were no cases of fungal endophthalmitis. Empiric antimycotic prophylaxis initiated at the time of positive culture result reduced the incidence of keratitis from 15.8% in untreated cases to 1.9% in treated cases (P = 0.056).

CONCLUSIONS

Positive donor rim fungal cultures are uncommon, but carry an unacceptably high risk of postoperative fungal infection. This risk may be reduced with prophylactic antimycotic therapy when culture-positive donor rims are identified.

Candida Interface Infections After Descemet Stripping Automated Endothelial Keratoplasty

PURPOSE

To describe 2 Candida interface keratitis infections occurring in the setting of positive donor rim cultures from precut corneal tissue used for Descemet stripping automated endothelial keratoplasty (DSAEK) and the ensuing public health investigation.

METHODS

Following 2 clinical Candida interface keratitis infections, patients from 2012 to 2014 in the same surgical center were evaluated for bacterial and fungal rim cultures and subsequent infection. All cases of fungal infections occurring post-DSAEK were analyzed. Data included patient demographics, surgical technique, donor rim cultures, donor mate outcomes, clinical courses, and outcomes. A review of the relevant literature was also undertaken.

RESULTS

From 2012 to 2014, among 99 DSAEK procedures performed, 7 (7.1%) donor rim cultures were positive for fungi. Use of this tissue with positive donor rim cultures resulted in 2 (28.6%) episodes of confirmed fungal interface keratitis, both Candida species, and presumptive treatment in an additional 2 patients. An investigation did not identify any breach in sterile technique or procedures by the surgeon or surgery center. Our literature review identified 15 reports of postoperative fungal infection associated with DSAEK, of which 11 involved Candida spp.

CONCLUSIONS

While postoperative infection remains rare, our 2 additional cases along with those previously reported suggest that DSAEK may be susceptible to infection with Candida spp. Furthermore, this report of correlated rim cultures and clinical infection suggests a need for reevaluation of the utility of obtaining routine corneoscleral donor rim fungal culture.

A comparative, retrospective, observational study of the clinical and microbiological profiles of post-penetrating keratoplasty keratitis

Infectious keratitis after penetrating keratoplasty (PK) is a devastating condition that may result in graft failure and poor visual outcome. In this study, we retrospectively reviewed the medical records of patients who underwent PK between 2009 and 2014, and recorded those who developed infectious keratitis. We compared the predisposing factors and organisms isolated to those identified in our previous study, conducted between 1989 and 1994. The incidence of post-PK infectious keratitis decreased from 11.6% (41 out of 354 cases, 1989–1994) to 6.5% (9 out of 138 cases, 2009–2014). Graft epithelial defect and suture-related problems remained the leading two risk factors of infectious keratitis after PK. Gram-positive and Gram-negative bacterial infection decreased from 58.5% and 46.3% to 11.1% and 22.2%, respectively (P = 0.023 and P = 0.271). In contrast, fungus infection increased from 9.8% to 66.7% (P = 0.001); fungi have become the major pathogen for post-PK infectious keratitis. In conclusion, while the incidence of post-PK infectious keratitis has decreased over time, the number and frequency of fungal infections have significantly increased in the recent study period. Clinicians should be aware of the shifting trend in pathogens involved in post-PK infectious keratitis.

Current Concepts in the Management of Unique Post-keratoplasty Infections

As corneal transplantation has evolved, the spectrum of post-surgical infection has changed and often presents a diagnostic and therapeutic challenge. Lamellar techniques hold the potential of improved outcomes and decreased post-operative complications, however, they create a lamellar interface, which is a potential space for sequestration of infectious organisms. In addition, while keratoprosthesis offers vision to patients who are poor candidates for traditional keratoplasty, infectious complications can be severe and sight threatening. Although antimicrobials remain the mainstay of treatment, definitive management often requires surgical intervention.

Intrastromal antifungal injection with secondary lamellar interface infusion for late-onset infectious keratitis after DSAEK

PURPOSE

The aim of this study was to report the successful medical management of 2 cases of late-onset endothelial keratoplasty-related stromal interface infections.

METHODS

All cases of endothelial keratoplasty-related infections treated with intrastromal antifungal injections were compiled. The following information was collected: demographic data, surgical indications, donor rim cultures, donor mate outcomes, clinical course, diagnostic tests, and clinical outcome.

RESULTS

Two cases of interface fungal keratitis diagnosed on clinical appearance and confocal microscopy were identified. Both patients refused to undergo further surgery and failed systemic and/or topical therapy. Each received 3 to 4 intrastromal injections, with secondary infusion into the graft-host interface, which resulted in the complete involution of their interface opacities.

CONCLUSIONS

Intrastromal antifungal injection may be an effective alternative to surgical intervention in late-onset fungal Descemet stripping endothelial keratoplasty interface keratitis. Early treatment may preserve graft viability and result in a good visual outcome without the need for either penetrating keratoplasty or potential pathogen exposure to the anterior chamber.

A year of cornea in review: 2013

PURPOSE

The goal of this study was to provide an update of significant corneal literature published in 2013.

DESIGN

This study is a systematic literature review.

METHODS

We conducted a systematic review of the English-language literature published from January 1, 2013, to December 31, 2013, using the following PubMed search and Medical Subject Headings terms: cornea transplantation, keratoplasty, Descemet membrane endothelial keratoplasty, Descemet stripping endothelial keratoplasty, cross linking, pre-Descemet's layer, Rho-associated kinase, keratoprosthesis, infectious keratitis, corneal dystrophy, corneal astigmatism, and keratoconus.

RESULTS

This review summarizes relevant and innovative original articles, review articles, and novel techniques from the following journals: American Journal of Ophthalmology, British Journal of Ophthalmology, Cornea, Graefe's Archive for Clinical and Experimental Ophthalmology, Investigative Ophthalmology & Visual Science, JAMA Ophthalmology, Journal of Cataract and Refractive Surgery, Journal of Refractive Surgery, and Ophthalmology. Case reports, abstracts, letters to the Editor, and unpublished work were excluded, as well as articles e-published ahead of print in 2012 that were discussed in the previous review. One hundred twenty-seven articles met the criteria for this review.

CONCLUSIONS

This review summarizes significant cornea-related literature from 2013.

Eye banking and corneal transplantation communicable adverse incidents: current status and project NOTIFY

PURPOSE

Evidence of the transmission of disease via donor ocular tissue has been demonstrated for adenocarcinoma, rabies, hepatitis B virus, cytomegalovirus, herpes simplex virus, Creutzfeldt-Jakob disease, and a variety of bacterial and fungal infections.

METHODS

Although there is no evidence to date of disease transmission for HIV infection, syphilis, hepatitis C, hepatitis A, tuberculosis, HTLV-1 and -2 infection, active leprosy, active typhoid, smallpox, and active malaria, these entities remain contraindications for transplantation for all eye banks nationally and internationally. The potential sources of contamination include infected donors, during the process of removing tissue from cadaveric donors, the processing environment, and contaminated supplies and reagents used during processing. The transmissions of Herpes simplex virus and HSV via corneal graft have been shown to be responsible for primary graft failure. HSV-1 may also be an important cause of PFG.

RESULTS

The long latency period of some diseases, the emergence of new infectious disease, and the reemergence of others emphasize the need for long-term record maintenance and effective tracing capabilities.

CONCLUSIONS

The standardization of definitions for adverse events and reactions will be necessary to support the prevention and transmission of disease. International classification of a unique identification system for donors will be increasingly important for vigilance and traceability in cross-national exportation of human cells, tissues, and cellular- and tissue-based products. Opportunities for continuous improvement exist as does the need for constant vigilance and surveillance.