Update on antifungal agents

Optical coherence tomography findings in fungal uveitis

PURPOSE

The purpose of the study was to describe the vitreal, retinal, and choroidal features of eyes affected by endogenous endophthalmitis (EE) and evaluate the effects of systemic antifungal drug treatment and pars plana vitrectomy by using spectral domain optical coherence tomography (SD-OCT).

METHODS

Medical records and SD-OCT images of eyes diagnosed with EE at a single uveitis tertiary referral center in Brazil were acquired at the time of diagnosis, after 7 days of high-dose antifungal drug treatment, and at follow-up assessments performed 30 days after resolution.

RESULTS

Thirteen eyes were enrolled in the study. All patients showed hyperreflective round-shaped lesions on SD-OCT and pre-retinal aggregates. Five eyes responded to antifungal systemic oral drugs despite showing vitreous opacity. The response to treatment was observable on optical coherence tomography (OCT) images.

CONCLUSION

Fungal endophthalmitis showed typical features on SD-OCT, facilitating early diagnosis and treatment despite the absence of vitreous culture or biopsy. This study suggests that OCT images can be used to support diagnosis by physicians who do not have access to vitreoretinal surgery.

Lipo-PEG nano-ocular formulation successfully encapsulates hydrophilic fluconazole and traverses corneal and non-corneal path to reach posterior eye segment

The present study describes a special lipid-polyethylene glycol matrix solid lipid nanoparticles (SLNs; 138 nm; -2.07 mV) for ocular delivery. Success of this matrix to encapsulate (entrapment efficiency - 62.09%) a hydrophilic drug, fluconazole (FCZ-SLNs), with no burst release (67% release in 24 h) usually observed with most water-soluble drugs, is described presently. The system showed 164.64% higher flux than the marketed drops (Zocon^®) through porcine cornea. Encapsulation within SLNs and slow release did not compromise efficacy of FCZ-SLNs. Latter showed in vitro and in vivo antifungal effects, including antibiofilm effects comparable to free FCZ solution. Developed system was safe and stable (even to sterilisation by autoclaving); and showed optimal viscosity, refractive index and osmotic pressure. These SLNs could reach up to retina following application as drops. The mechanism of transport via corneal and non-corneal transcellular pathways is described by fluorescent and TEM images of mice eye cross sections. Particles streamed through the vitreous, crossed inner limiting membrane and reached the outer retinal layers.

Whey-derived free fatty acids suppress the germination of Candida albicans in vitro

Bovine whey from the cheese-making industry contains several bioactive factors that promote health and prevent disease. Although many efforts have been made over the years to show that immunoglobulins, lactoperoxidase, lactoferrin, lysosyme and small peptides present in whey have antimicrobial activities against several pathogenic microorganisms, such activities have not been investigated so far for the lipid fraction of whey. Here, we have used an in vitro assay-based fractionation procedure to show that free fatty acids derived from whey cream specifically inhibit the germination of Candida albicans, a morphologic change associated with pathogenicity. Further fractionation by HPLC demonstrated that this activity can be mainly attributed to lauric acid, myristoleic acid, linoleic acid and arachidonic acid.

INTRAVITREAL VORICONAZOLE FOR DRUG-RESISTANT FUNGAL ENDOPHTHALMITIS

PURPOSE

To report the efficacy of intravitreal voriconazole.

METHODS

Retrospective analysis of an interventional case series of five cases of culture-proven fungal endophthalmitis treated with intravitreal voriconazole was done. Only cases found to be resistant to conventional antifungal agents were included in the study. The diagnosis of fungal endophthalmitis was established on the basis of clinical as well as microbiological examination. All patients received one or more intravitreal injections of voriconazole. Resolution was determined on the basis of clinical examination. Resolution of infection and final visual acuity were the main outcome measures.

RESULTS

Resolution of infection was achieved in all five cases. Visual acuity was better in three cases and was maintained in two. Of the three patients who had improvement, two had vision better than or equal to 20/120. Evisceration was avoided in one case with maximal antifungal treatment including voriconazole.

CONCLUSIONS

Voriconazole definitely adds to the available treatment options for fungal endophthalmitis. Because of its broad spectrum of activity, it is efficacious in even amphotericin-B- and fluconazole-resistant fungal endophthalmitis.

Pseudoporphyria as a result of voriconazole use: a case report

Voriconazole, a second-generation triazole, has recently been approved by the Food and Drug Administration (FDA) to treat invasive aspergillosis and refractory infections with Scedosporium apiospermum or Fusarium spp. The reported side-effects of voriconazole include visual changes, headaches, elevated hepatic enzymes, Steven-Johnson syndrome, toxic epidermal necrolysis, chelitis, photosensitivity, discoid lupus erythematosus and anaphylactoid infusion reactions. Pseudoporphyria was first described in association with nalidixic acid. It has the same clinical and histologic features as porphyria cutanea tarda (PCT) but is distinguished by normal porphyrin levels in the serum, urine and stool. We present the case of a patient who developed pseudoporphyria after receiving treatment with voriconazole.