Use of voriconazole in the treatment of fungal keratitis

Oral voriconazole monotherapy for fungal keratitis: efficacy, safety, and factors associated with outcomes

Purpose

To provide preliminary data on the efficacy and safety of oral voriconazole (VCZ) as a primary treatment for fungal keratitis (FK).

Method

We performed a retrospective histopathological analysis of data on 90 patients with FK at The First Affiliated Hospital of Guangxi Medical University between September 2018 and February 2022. We recorded three outcomes: corneal epithelial healing, visual acuity (VA) improvement, and corneal perforation. Independent predictors were identified using univariate analysis, and multivariate logistic regression analysis was used to identify independent predictive factors associated with the three outcomes. The area under the curve was used to evaluate the predictive value of these factors.

Results

Ninety patients were treated with VCZ tablets as the only antifungal drug. Overall, 71.1% (n = 64) of the patients had extreme corneal epithelial healing, 56.7% (n = 51) showed an improvement in VA, and 14.4% (n = 13) developed perforation during treatment. Non-cured patients were more likely to have large ulcers (≥5 × 5 mm²) and hypopyon.

Conclusion

The results indicated that oral VCZ monotherapy was successful in the patients with FK in our study. Patients with ulcers larger than 5 × 5 mm² and hypopyon were less likely to respond to this treatment.

Postoperative Fungal Keratitis Managed by Anterior Chamber Washout and Intracameral Amphotericin-B: A Report of Two Cases

Keratomycosis is a significant cause of mono-ocular blindness, especially in tropical regions. Fungal keratitis developing in corneal incisions is very rare. We report the experience of treating two patients diagnosed with recalcitrant candida keratitis post-phacoemulsification with anterior chamber washout and deep debridement. The first patient was a 68-year-old woman who underwent left eye phacoemulsification nine months ago with a postoperative best corrected visual acuity of 6/6. The second patient was a 73-year-old man who had uneventful right eye phacoemulsification six months prior with a postoperative best corrected visual acuity of 6/9. Both patients used topical steroids postoperatively for more than three months and noted a drop in vision. Both patients had deep stromal infiltration and endothelial plaque at the primary corneal wound. They were unresponsive to topical, intracameral, and systemic antifungal therapy. Both patients underwent anterior chamber evacuation of hypopyon and endothelial plaque removal. Evacuation of hypopyon and removal of endothelial plaque was done with a 23G vitrectomy cutter using a low-powered vacuum controlled at 200 mmHg. The fluid inside the tubing was sent for culture analysis. We used viscoelastic coating on the endothelium to minimize the damage during the operations. Intracameral amphotericin B 15 µg/0.1 ml was given at the end of the operation. Postoperatively, both patients had clear corneas. The first patient’s visual acuity improved 6/18, and the second patient’s visual acuity improved to 6/9. Both cultures isolated Candida parapsilosis sensitive to amphotericin. These patient cases highlight that evacuation of the anterior chamber infiltration in recalcitrant fungal keratitis and intracameral injection of amphotericin B can be an effective adjuvant therapy.

Late outcome after surgical and topical treatment for Aspergillus mediastinitis after heart transplantation

The 7-year long-term survival after Aspergillus fumigatus mediastinitis after heart transplantation, an uncommonly described condition, is herein reported. A 66-year-old male developed an infection with A. fumigatus covering the entire thoracic cavity with a fungal turf after orthotopic heart transplantation. Repeated surgical removal of infectious and necrotic tissue together with innovative topical treatment using voriconazole and chlorhexidine combined with systemic antifungal treatment, helped in controlling the infection. Definitive wound closure was achieved by standard sternal refixation and latissimus dorsi muscle flap plasty. Survival after A. fumigatus mediastinitis after heart transplantation was achieved with sequential debridement in combination with topical application of antifungal agents.

Combined Intrastromal Voriconazole and Amphotericin B Treatment for Persistent Fungal Keratitis

PURPOSE

To evaluate the clinical outcomes of combined intrastromal voriconazole and intrastromal amphotericin B for the treatment of persistent fungal keratitis.

METHOD

Patients who received combined corneal intrastromal voriconazole (0.05 mg/0.1 mL) and intrastromal liposomal amphotericin B (0.01 mg/0.1 mL) injections in addition to topical therapy for treatment of persistent fungal keratitis were included in the study. Persistence was described as no improvement or progression in the clinical findings despite treatment with combined topical voriconazole (1 mg/0.1 mL) and topical amphotericin B drops (0.15 mg/0.1 mL) hourly for at least 10 days. The healing of keratitis was considered as the complete closure of epithelial defect with complete resolution of a corneal infiltrate.

RESULTS

Thirty-two eyes of 32 patients who met the inclusion criteria were included in this study. Predominant organisms in fungal isolates were Aspergillus species. Combination therapy of intrastromal amphotericin B and intrastromal voriconazole in addition to topical therapy resulted in complete resolution of persistent fungal keratitis in 28 (87.5%) patients. The mean number of intrastromal injections was 9.3±6.4 and ranged from 1 to 18. The mean best-corrected visual acuity values improved from 2.17±0.43 to 1.76±0.77 logarithm of the minimum angle of resolution units (P=0.003). The mean duration of complete epithelial closure was 45.3±16.3 days. Four patients required therapeutic penetrating keratoplasty because of persistence of fungal keratitis (3 patients) and progression of keratitis (1 patient). There was no need for evisceration.

CONCLUSION

Combination therapy with intrastromal voriconazole and intrastromal amphotericin B may be an effective adjunct treatment for persistent fungal keratitis.

Design and evaluation of topical solid dispersion composite of voriconazole for the treatment of ocular keratitis

Aim: The objective of present investigation was to increases solubility of voriconazole by using solid dispersion techniques and the development of solid dispersion-based voriconazole ophthalmic solutions. Materials & methods: The saturation solubility of solid dispersion containing polyvinylpyrrolidone K90 (PVPK-90) was found to increase the solubility of voriconazole compare other carrier like polyethylene glycol and Polyvinylpyrrolidone K 30 (PVPK-30). Solid dispersion of voriconazole was characterized by saturation solubility, Fourier-transform infrared spectroscopy and Differential scanning calorimetry study. Results & conclusion: The Fourier-transform infrared spectroscopy and Differential scanning calorimetry studies of voriconazole-based solid dispersion confirmed the complete changes in original polymorphic form of voriconazole. The antifungal assay showed that the maximum zone of inhibition was produced from optimized ophthalmic formulation containing sodium alginate as compared with other formulations and marketed eye drops.

Rapamycin liposome gutta inhibiting fungal keratitis of rats

AIM

To study the therapeutic effect of rapamycin liposome eyedrops on fungal keratitis (FK) and its effect on the expression of monocyte chemotactic protein-1 (MCP-1).

METHODS

This study adopted the thin film dispersion method to prepare rapamycin liposomes eyedrops, as well as used the orthogonal design to analyze and study main influencing factors that affected the quality of liposomes. Totally 96 healthy Wistar rats were randomly divided into four groups: normal control group (A), FK blank control group (B), FK blank liposomes control group (C), and 30 FK rapamycin liposome treatment group (D). Groups B, C, and D were first prepared as FK animal models. The corneal response was recorded in details on day 1, 3, 5, 7, and 14 after modeling. Six rats were obtained and immunohistochemistry and semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) were used to detect the expression of MCP-1 protein and mRNA, respectively.

RESULTS

The severity of corneal lesions in the rapamycin treatment group was reduced, and the clinical score of the slit lamp examination was lower than that of Groups B and C (P<0.01). The expression of MCP-1 in rapamycin treatment group was significantly inhibited, comparing to that of groups B and C (P<0.01).

CONCLUSION

Liposome is a good drug carrier for rapamycin. Rapamycin has a good therapeutic effect on FK. It can reduce FK fungal burden and significantly inhibit the expression of MCP-1 protein and mRNA.

Corneal Debridement Combined with Intrastromal Voriconazole for Recalcitrant Fungal Keratitis

Background

To analyze the therapeutic effects of corneal debridement combined with intrastromal voriconazole in recalcitrant fungal keratitis.

Methods

This is a retrospective study. Fourteen patients with recalcitrant fungal keratitis were treated by corneal debridement combined with intrastromal voriconazole (50 μg/0.1 ml). This paper reviews and analyzes the patients' basic state, surgical intervention, medicinal treatment, and outcomes.

Results

The mean sizes of infiltration and ulcer were (5.54 ± 1.32)mm and (3.46 ± 1.03)mm, respectively, and the mean depth was (315.43 ± 57.72)μm. Twelve of the patients had satellite lesion, and 2 suffered hypopyon. After intrastromal voriconazole, the size of infiltration decreased significantly to (4.32 ± 1.10)mm (P < 0.001), but there was no significant change in ulcer size ((3.36 ± 0.92)mm, P = 0.082). Thirteen patients were cured after corneal debridement. The mean healing time was (15.38 ± 7.38) days. Excluding one cured patient with optic nerve atrophy and one patient for whom the treatment failed, the mean best-corrected visual acuity after healing was (0.23 ± 0.18)LogMAR, a significant improvement compared to pretreatment (0.87 ± 0.57(LogMAR), P = 0.01). The mean corneal astigmatism was (1.3 ± 1.6)D of 12 cured patients after healing and (1.0 ± 0.7)D at final follow-up, and there was no significant difference (P = 0.374).

Conclusions

Corneal debridement combined with intrastromal voriconazole is a secure and effective treatment for recalcitrant fungal keratitis.

Argon laser photocoagulation versus intrastromal voriconazole injection in treatment of mycotic keratitis

AIM

To compare argon laser photocoagulation and intrastromal injection of voriconazole as adjunctive treatment modalities in cases of resistant mycotic corneal ulcers.

METHODS

Two groups each of them included 20 cases of resistant mycotic corneal ulcers. Both groups treated with local and systemic specific antimicrobial drugs guided with culture and sensitivity results. In one group argon laser photocoagulation was used as an adjunctive therapy to the specific antifungal drugs and in the other group, intrastromal injection of voriconazole was done besides the specific antifungal drugs. The 40 cases included in the study were proven according to culture and sensitivity to be 28 cases with pure fungal results and 12 cases with mixed (fungal and bacterial). In argon laser group, argon laser irradiation of the corneal ulcer was performed using argon laser 532 nm wavelength (Carl Zeiss LSL 532s AG; Meditec, Inc.) after fluorescein staining. In the other group, voriconazole solution (500 µg/mL) was prepared and injected in the corneal stroma. All cases were followed up for 3mo after healing was achieved.

RESULTS

Complete healing of the epithelial defect and resolution of stromal infiltration with no adverse effects were achieved in argon laser group in duration ranged from 2-4wk in 90% of cases. In voriconazole group 4 cases needed amniotic membrane graft due to thinning and 16 cases healed in duration ranged from 2-6wk (80% of cases).

CONCLUSION

Argon laser photocoagulation is superior to intrastromal voriconazole injection in treatment of resistant fungal corneal ulcers.

Topical 5% Natamycin With Oral Ketoconazole in Filamentous Fungal Keratitis: A Randomized Controlled Trial

PURPOSE

To assess the role of additive oral antifungal therapy in deep keratitis caused by filamentous fungi.

DESIGN

A randomized, masked, double-blind clinical trial.

METHODS

All patients presenting with culture-positive fungal keratitis with a size measuring 2 to 60 mm2 and involving more than 50% of stromal depth were enrolled in 1 of the 2 treatment arms. Group A received 5% natamycin, whereas Group B was given 200mg of oral ketoconazole twice a day in addition to 5% natamycin. Patients were followed up for 4 weeks. Liver function was assessed at baseline and at exit. Tests for significance included t test to compare the means of continuous variables, chi-square and Fisher's exact tests for comparing categorical variables and Kaplan-Meier procedure to estimate the survival rate.

RESULTS

Of the 115 patients enrolled, 108 completed the study. Fifty-eight patients were in group A and 57 in group B. There was no significant difference in baseline characteristics or in ulcer characteristics between the 2 groups. In group A, 68.5% of the patients responded favorably to medical therapy, whereas in group B, 72.2% responded favorably. There was no statistically significant difference in healing between the 2 groups (P = -0.618). All patients had normal liver functions during the study.

CONCLUSIONS

Although safe, oral ketoconazole did not add significant benefit to topical natamycin therapy in treating deep fungal keratitis. The efficacy of newer antifungal agents and drug delivery routes needs to be explored.

Effect of formulation factors on in vitro transcorneal permeation of voriconazole from aqueous drops

The purpose of this research was to evaluate the effect the formulation factors on in vitro permeation of voriconazole through freshly isolated goat and sheep corneas. An increase in the pH of the drops from 4.0 to 8.0 resulted in significant (P < 0.05) increase drug permeation. Raising concentration of the drops from 0.05% to 0.2% (w/v) significantly, (P < 0.05) increased drug permeation, but decreased the percent permeation. Corneal transport of voriconazole is both pH and concentration dependent. Eye drops containing disodium edetate (ethylenediaminetetraacetic acid) alone or combination with benzalkonium chloride showed significantly (P < 0.05) higher permeation as compared with control formulation. Addition of beta-cyclodextrin to the formulation enhanced corneal permeation of voriconazole. Compared with control formulation, voriconazole 0.2% (w/v) drop containing viscosity modifier produced significant (P < 0.05) decrease in permeation. Most of the formulations showed higher zone of inhibition against Candida albicans.

Protective role of murine β-defensins 3 and 4 and cathelin-related antimicrobial peptide in Fusarium solani keratitis

Antimicrobial peptides (AMPs), such as β-defensins and cathelicidins, are essential components of innate and adaptive immunity owing to their extensive multifunctional activities. However, their role in fungal infection in vivo remains elusive. In this study, we investigated the protective effect of murine β-defensin 3 (mBD3), mBD4, and the cathelicidin cathelin-related antimicrobial peptide (CRAMP) in a murine model of Fusarium solani keratitis. C57BL/6 mice showed significant corneal disease 1 and 3 days after infection, which was accompanied by enhanced expression of β-defensins and CRAMP. Disease severity was significantly improved 7 days after infection, at which time AMP expression was returning to baseline. Mice deficient in mBD3 (genetic knockout), mBD4 (short interfering RNA knockdown), or CRAMP (genetic knockout) exhibited enhanced disease severity and progression, increased neutrophil recruitment, and delayed pathogen elimination compared to controls. Taken together, these data suggest a vital role for AMPs in defense against F. solani keratitis, a potentially blinding corneal disease.

Management of recurrent Paecilomyces lilacinus keratitis

A 72-year-old man presented with Paecilomyces keratitis subsequent to immunosuppressive treatment. Despite medical therapy with voriconazole, perforation occurred requiring a tectonic keratoplasty of 10 mm. Despite oral, topical and intracameral voriconazole, there was recurrent stromal infiltration. A corneoscleral graft of 15 mm was undertaken. Two weeks later, hyphae were seen on the anterior lens capsule with hypopyon requiring phacoemulsification and anterior chamber washout. Six weeks later, there was evidence of endophthalmitis. Pars plana vitrectomy, capsulectomy and intravitreal injection of voriconazole were performed. Voriconazole treatment was continued for a further 10 months and then ceased. At 16 months following the last recurrence of Paecilomyces, there was no evidence of infection. After 20 months, the patient had a sutured intraocular lens with an artificial iris. Vision is 6/36 unaided and 6/24 pinhole.

Candida keratitis: emerging problem in India

PURPOSE

To determine the epidemiological characteristics and outcome of Candida keratitis in a Cornea Care Unit of Kolkata-based tertiary eye hospital.

METHODS

A retrospective, noncomparative, observational case series involving patients of culture-proven fungal keratitis from January 2008 to December 2008. A total of 85 cases of culture-proven fungal keratitis were identified. Of these, 16 cases were caused by Candida sp and selected for the study. The records were analyzed for demographics, risk factors, mode of management (medical or surgical), indication of surgical therapy, and the response to treatment with final outcome. Medical therapy consisted of topical amphotericin B with or without intracameral application after obtaining culture reports. Surgical therapy included application of tissue adhesive with bandage contact lens and therapeutic keratoplasty.

RESULTS

All cases of Candida keratitis were caused by Candida albicans accounting for 16 cases [18.81%; 95% confidence interval (CI), 11.8-28.5] of total culture-positive fungal keratitis. We found postsurgical steroid therapy in 8 cases as most important association, followed by diabetes and trauma (4 cases each) as next common comorbidities. All patients required therapeutic keratoplasty. Surgical indications were corneal melt in 10 cases (62.5%; 95% CI, 38.5-81.6), extension up to limbus in 2 cases (12.5%; 95% CI, 12.2-37.2) and nonresponse with worsening in 4 cases (25%; 95% CI, 19.7-49.9). Final outcome consists of phthisis bulbi in 3 cases (18.8%; 95% CI, 5.8-43.8), failed graft in 7 cases (43.7%; 95% CI, 23-66.8), and clear graft in 6 cases (37.5%; 95% CI, 18.4-61.5).

CONCLUSIONS

Candida is a new concern in developing countries like India. We are concerned about the poorer outcome, probably resulting from our unpreparedness and failure of medical therapy leading to more complication and requiring surgical intervention in higher numbers.

Fungal keratitis

CLINICAL QUESTION

What is the most appropriate management of fungal keratitis?

RESULTS

Traditionally, topical Natamycin is the most commonly used medication for filamentous fungi while Amphotericin B is most commonly used for yeast. Voriconazole is rapidly becoming the drug of choice for all fungal keratitis because of its wide spectrum of coverage and increased penetration into the cornea.

IMPLEMENTATION

Repeated debridement of the ulcer is recommended for the penetration of topical medications. While small, peripheral ulcers may be treated in the community, larger or central ulcers, especially if associated with signs suggestive of anterior chamber penetration should be referred to a tertiary center. Prolonged therapy for approximately four weeks is usually necessary.

Extensive long-standing chromomycosis due to Fonsecaea pedrosoi: three cases with relevant improvement under voriconazole therapy

OBJECTIVE

To evaluate voriconazole in the treatment of extensive cases of chromomycosis. Chromomycosis is a chronic infection, which is extremely difficult to eradicate, and is caused by dematiaceous (dark-colored) fungi which affect the skin and subcutaneous tissues, with Fonsecaea pedrosoi being the major etiologic agent. Drugs such as itraconazole, terbinafine, posaconazole and amphotericin B have been employed with variable results.

METHODS

We treated three Caucasian male patients (ages 44, 57 and 77 years), two were farmers and one a trash collector, with long-standing (20, 10 and 21 years of disease, respectively) and extensive chromomycosis (one lower limb affected, at least) due to Fonsecaea pedrosoi. All patients had received previous therapy with the formerly indicated drugs itraconazole and terbinafine for several months either without or with incomplete response. After that, we started treatment with voriconazole per os 200 mg twice a day.

RESULTS

The patients were treated with voriconazole for 12 months until there was clinical and mycological improvement. Clinical response was evident after 30-50 days. One patient developed visual abnormalities and tremors, and the voriconazole was reduced to 200 mg/day without impairment of the clinical and mycological response. The same patient presented photosensitive dermatitis after 12 months of therapy and the voriconazole was stopped. All patients showed elevations of serum gamma-glutamyl transpeptidase (GGT) during the treatment without clinical relevance. Moreover, our three patients obtained partial response with this therapy.

CONCLUSIONS

This is the first report with a case series of chromomycosis treated with voriconazole. Despite its high cost, voriconazole is a safe and possibly promising drug for use on extensive chromomycosis refractory to conventional treatment.

Clinical utility of voriconazole eye drops in ophthalmic fungal keratitis

Fungal keratitis is one of the major causes of ophthalmic mycosis and is difficult to treat. The range of common antifungal agents available for fungal keratitis remains inadequate and is generally associated with poor clinical outcomes. Voriconazole is a new generation triazole antifungal agent. Only marketed in systemic formulation and, with broad-spectrum activity and high intraocular penetration, voriconazole has demonstrated effectiveness against fungal keratitis. Systemic voriconazole, however, is not without side effects and is costly. Voriconazole eye drops have been prepared extemporaneously and used for the treatment of ophthalmic fungal keratitis. The current article sought to review the literature for evidence related to the effectiveness and safety of topical voriconazole and its corneal penetration into the aqueous humor of the eye. The voriconazole eye drops used are typically of 1% concentration, well tolerated by the eye, and are stable. Despite existing evidence to suggest that the eye drops are effective in the treatment of fungal keratitis, more studies are needed, especially in relation to using the eye drops as first-line and stand-alone treatment, preparation of higher concentrations, and optimal dosing frequency.

Practice patterns in the management of fungal corneal ulcers

PURPOSE

The purpose of this study was to determine the practice patterns of ophthalmologists in the management of fungal corneal ulcers.

METHODS

In December 2007, a survey of 13 questions addressing the actual and preferred treatment of fungal ulcers was sent to the kera-net e-mail listserv facilitated by the Cornea Society.

RESULTS

Ninety-two respondents from North America, South America, Asia, Europe, and Australia participated by completing the electronic questionnaire. Natamycin was the most commonly used topical treatment for ulcers caused by filamentous fungi (96%) followed by amphotericin (75%) and voriconazole (63%). However, voriconazole was most often listed as the preferred topical treatment in an ideal world (79%) compared with 55% for natamycin. Approximately half of the respondents use combination topical therapy (56%) and the remainder monotherapy. The majority of respondents rescrape the epithelium at some time during the course of treatment, but the frequency of rescraping varied among the different topical treatments. The most common reasons cited for not using their preferred treatment were cost and a desire for further evidence to support preferred treatment.

CONCLUSION

There appears to be significant variation in the management of fungal corneal ulcers. Although natamycin was the most commonly used treatment for ulcers caused by filamentous fungi, voriconazole was the most preferred as the ideal treatment. These results highlight the need for more evidence regarding the efficacy of the newer topical antifungals.

Fungal keratitis: changing pathogens and risk factors

PURPOSE

To describe changes in demographics and pathogens for fungal keratitis cases diagnosed at the Massachusetts Eye and Ear Infirmary.

METHODS

Patient demographics, clinical and laboratory findings, treatment and outcomes of 46 cases of culture-proven fungal keratitis diagnosed from January 2004 through November 2007 were compared with 23 cases of fungal keratitis previously collected over a similar period from January 1999 through November 2002.

RESULTS

During 2004-2007, the rate of fungal keratitis was 1.0 cases per month, an increase from the baseline rate of 0.5 cases per month during 1999-2002. The proportion of cases caused by filamentous fungi increased from 30% (1999-2002) to 65% (2004-2007) (P = 0.01). Soft contact lens wear accounted for 41% of fungal keratitis cases in 2004-2007, as compared with 17% in 1999-2002. The majority of patients (70%) received oral antifungal treatment in addition to topical amphotericin B and natamycin. Seventeen patients (40%) required therapeutic keratoplasty. Patients with a history of corneal transplant had the highest rate of therapeutic keratoplasties (67%) and had the poorest visual outcome (40% counting fingers or less). In the contact lens group, 94% of patients maintained vision of at least 20/40 and only 12% required surgery to control the infection.

CONCLUSIONS

There has been an increase in fungal keratitis in the Boston area and a change in the causative pathogens and risk factors for infection. Filamentous fungi now account for the majority of fungal keratitis cases, whereas yeasts were the predominant pathogen in the past. Soft contact lens wear is currently the most common risk factor for development of fungal keratitis.

Prospective open-label study of the administration of two-percent voriconazole eye drops

Thirteen human subjects scheduled for elective anterior segment eye surgery received hourly 2% voriconazole eye drops 4 hours presurgery. No side effects were reported. Significantly, the voriconazole concentration in the aqueous humor of the eye was similar to that reported for the 1% voriconazole solution, suggestive of concentration-independent absorption.