Purpose To compare the in vitro effect of rose bengal and riboflavin as photosensitizing agents for photodynamic therapy (PDT) on fungal isolates that are common causes of fungal keratitis Design Experimental study Methods Three isolates (Fusarium solani, Aspergillus fumigatus, Candida albicans) recovered from patients with confirmed fungal keratitis were used in the experiments. Isolates were grown on Sabouraud-Dextrose agar, swabbed and prepared in suspension, and one milliliter aliquots were inoculated onto test plates in triplicate. Test plates were separated into 5 groups: Group 1 - no treatment, Group 2 - 0.1% rose bengal alone, Group 3 - 518 nm irradiation alone, Group 4 - riboflavin PDT (riboflavin + 375 nm irradiation), and Group 5 - rose bengal PDT (rose bengal + 518 nm irradiation). Irradiation was performed over a circular area using either a green LED array (peak wavelength: 518 nm) or a UV-A LED array (peak wavelength: 375 nm). Test plates were irradiated with an energy density of 5.4 J/cm2. Later, plates were placed in a 30° C incubator and observed for growth. Results Rose bengal-mediated PDT successfully inhibited the growth of all three fungal isolates in the irradiated area. All other groups exhibited unrestricted growth throughout the plate. Conclusions Rose bengal-mediated PDT successfully inhibited the growth of three types of fungi. No other experimental groups, including riboflavin-mediated PDT, had any inhibitory effect on the isolates. The results might be useful for the treatment of patients suffering from corneal infection.

Rose bengal- and riboflavin-mediated photodynamic therapy demonstrated complete growth inhibition in vitro of 2 multidrug-resistant MRSA strains. Rose bengal was also effective in dark and ambient conditions. These results may have implications for in vivo therapy.

Choroidal neovascularization (CNV) is a major cause of visual impairment in patients suffering from wet age-related macular degeneration (AMD), particularly when refractory to intraocular anti-VEGF injections. Here we report that treatment with the oral mineralocorticoid receptor (MR) antagonist spironolactone reduces signs of CNV in patients refractory to anti-VEGF treatment. In animal models of wet AMD, pharmacological inhibition of the MR pathway or endothelial-specific deletion of MR inhibits CNV through VEGF-independent mechanisms, in part through upregulation of the extracellular matrix protein decorin. Intravitreal injections of spironolactone-loaded microspheres and systemic delivery lead to similar reductions in CNV. Together, our work suggests MR inhibition as a novel therapeutic option for wet AMD patients unresponsive to anti-VEGF drugs.

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Background Fungal keratitis is a commonly occurring cause of corneal blindness which does not always respond to standard antifungal treatment. Rose bengal photodynamic antimicrobial therapy represents an alternative treatment that has worked in vitro and that was successfully implemented in the clinic to treat an aggressive infectious keratitis case. Purpose To evaluate the efficacy of rose bengal photodynamic antimicrobial therapy (PDAT) for the management of a patient with multidrug-resistant Fusarium keratoplasticum keratitis unresponsive to standard clinical treatment. Results In vitro results demonstrated the efficacy of rose bengal PDAT against a multidrug-resistant Fusarium keratoplasticum species. There was complete fungal inhibition in our irradiation zone on the agar plates. In the clinical case, the patient was successfully treated with two sessions of rose bengal PDAT, and at the eight month follow-up, there was no recurrence of infection nor adverse effects to report. Conclusions and Relevance Rose bengal PDAT is a novel treatment that may be considered in cases of aggressive infectious keratitis. Further studies are needed to understand the mechanisms of PDAT in-vivo.

BackgroundCurrent visual field screening machines are bulky and expensive, limiting their accessibility, affordability and use. We report the design and evaluation of a novel, portable, cost-effective system for glaucoma screening using smartphone-based visual field screening using frequency doubling technology (FDT) and a head-mounted display.MethodsNineteen eyes of 10 subjects with new-onset or chronic primary open angle glaucoma were tested and compared with the Humphrey Zeiss FDT and the newly developed Mobile Virtual Perimetry (MVP) FDT with the C-20 testing pattern. Mann-Whitney, Bland-Altman and linear regression analyses were performed to assess statistical difference, agreement and correlation, respectively, between the two devices.ResultsThe average age of the participants was 58±15 years. No statistically significant difference was found between the MVP FDT and the Humphrey Zeiss FDT (p>0.05). Bland-Altman and linear regression analyses demonstrated good agreement and correlation between the two devices.ConclusionThe MVP FDT is a low-cost, portable visual field screening device that produces comparable results to the Humphrey Zeiss FDT and may be used as an easily accessible screening tool for glaucoma.

Purpose To characterize the molecular, epidemiological, and resistance profiles of methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) keratitis isolates. Patients and methods We used a combination of standard microbiological techniques and DNA microarray analysis to characterize the molecular and antibiotic resistance profiles of 75 Staphylococcus aureus keratitis isolates collected over an 11-year period (2006–2016). Results Two major USA clonal complexes (CC), CC5 (n=30, 40%) and CC8 (n=28, 37.3%), accounted for 77.3% of the collected S. aureus isolates. USA100, traditionally healthcare associated (n=18/47, 38.3%), and USA300, traditionally community associated (n=12/47, 25.5%), were the dominant MRSA strains. Four (22.2%) of the USA100 MRSA isolates were recovered from patients with no prior healthcare exposure. Eleven (91.7%) of the USA300 isolates were recovered from patients with documented healthcare risk factors. MSSA isolates were polyclonal (n=13). Ninety-three percent of MSSA infections were of healthcare origin. Thirty-seven of 61 (60.6%) healthcare- and 11 of 14 (78.6%) community-associated strains were resistant to three or more antibiotic classes. Sixty-eight percent (n=51) of isolates harbored three of more resistance determinants (genes). The Panton-Valentine Leucocidin gene was detected in 11 (14.7%) of the study isolates. The majority (72.7%) of the strains were members of the USA300 MRSA clone. Conclusion Clonal complexes CC5 and CC8 were the most frequent clones detected among both the MSSA and the MRSA keratitis isolates. USA100 and USA300 clones were the dominant MRSA genotypes. The USA300 MRSA clone has become a leading cause of healthcare-associated keratitis in South Florida. The USA100 MRSA clone has emerged as an increasing cause of community-associated corneal infections in our outpatient population. This shifting epidemiology coupled with the increasing prevalence of multidrug resistance among both MSSA and MRSA keratitis is a cause of concern.

Global amphibian declines have been attributed to several factors including the chytrid fungal pathogen, Batrachochytrium dendrobatidis (Bd), that infects hosts’ skin and causes death by inhibiting immune response and impairing osmoregulatory function. Here, we integrate extensive new field data with previously published locality records of Bd in Colombia, a megadiverse and environmentally heterogeneous country in northwestern South America, to determine the relative importance of environmental variables and reproductive mode for predicting the risk of Bd infection in amphibians. We surveyed 81 localities across Colombia and sampled 2876 individual amphibians belonging to 14 taxonomic families. Through a combination of end‐point PCR and real‐time PCR analyses, Bd was detected in 338 individuals (12%) representing 43 localities (53%) distributed from sea level to 3200 m. We found that annual mean temperature and variables related with seasonality in precipitation and temperature appeared to define the most suitable areas for the establishment of the pathogen. In addition, prevalence of infection appeared to be higher in species with a terrestrial reproductive mode. Our study provides the first large‐scale study of the current and potential distribution of Bd in the biodiversity hotspot centered on Colombia. We hope the newly provided information on the extent of the distribution of the pathogen and the potential areas where Bd may impact the amphibian fauna will inform decision making by environmental authorities and future conservation action.