Use of corticosteroids in combination with antimicrobial drugs in the treatment of infectious corneal disease

Trends and Clinical Outcomes of Fungal Keratitis in Canada: A 20-year Retrospective Multicentre Study

PURPOSE

An increase in fungal and particularly filamentous keratitis has been observed in many geographic areas, mostly in contact lens wearers. This study seeks to characterize long-term trends in fungal keratitis in a continental climate area to provide guidance for diagnosis and treatment.

DESIGN

Retrospective multicentric case series.

METHODS

Cases of microbiology-confirmed fungal keratitis from 2003 to 2022 presenting to tertiary care centers across Canada were included. Charts were reviewed for patient demographics, risk factors, visual acuity, and treatments undertaken.

RESULTS

A total of 138 patients were identified: 75 had yeast keratitis while 63 had filamentous keratitis. Patients with yeast keratitis had more ocular surface disease (79% vs 28%) while patients with filamentous keratitis wore more refractive contact lenses (78% vs 19%). Candida species accounted for 96% of all yeast identified, while Aspergillus (32%) and Fusarium (26%) were the most common filamentous fungi species. The mean duration of treatment was 81 ± 96 days. Patients with yeast keratitis did not have significantly improved visual acuity with medical treatment (1.8 ± 1 LogMAR to 1.9 ± 1.5 LogMAR, P = .9980), in contrast to patients with filamentous keratitis (1.4 ± 1.2 LogMAR to 1.1 ± 1.3 LogMAR, P = .0093).

CONCLUSIONS

Fungal keratitis is increasing in incidence, with contact lenses emerging as one of the leading risk factors. Significant differences in the risk factors and visual outcomes exist between yeast keratitis and filamentous keratitis which may guide diagnosis and treatment.

Diagnostic Uses of Common Eye Drops

Medicated eye drops may have dual therapeutic and diagnostic uses that form part of the ophthalmic assessment paradigm. In this review article, commonly administered and prescribed eye drops were analyzed for their use as a diagnostic tool. It examines the common categories of eye drops-antimicrobial agents, topical anesthetics, mydriatics, and ocular anti-hypertensives, with respect to their therapeutic and diagnostic applications. Knowledge of the pharmacological effects of eye drops is an important aspect in performing clinical duties. Diagnostic tests by utilization of eye drops are safe, efficient, noninvasive, and informative to the eye care professional.

Nigrospora oryzae causing human corneal keratitis: A case report

Purpose

We report a rare case of microbial keratitis caused by Nigrospora oryzae.

Observations

A 72-year-old Japanese woman was injured by plant debris and developed oval corneal ulcers and hypopyon in the anterior chamber. After 5 days, she complained of pain, redness, and vision loss in her left eye and was treated with antibacterial eye drops and an ointment (1.5 % levofloxacin hydrate, cefmenoxime hydrochloride, and sterilization and disinfection eye drops; SAN-IODE and ofloxacin ophthalmic ointment). Examination revealed a worsening oval corneal ulcer with Descemet's folds and a faint hypopyon. Considering the infection from soil or plants and the poor response to intensive antibacterial eye drops, topical antifungal eye drops, i.e., 1 % voriconazole eye drops, and 1 % natamycin ointment were applied. Direct microscopy of the corneal scraping with Gram staining was performed and the result was negative. Cultures from corneal scrapings showed the growth of dark colonies after several days. The colony was identified as Nigrospora oryzae by sequencing of the fungal internal transcribed spacer region. Pain and vision loss improved with improvement in corneal ulcers. The antifungal treatment was administered for 37 days. Discontinuation of the eye drops after 1 month did not result in keratitis recurrence. At the final follow-up at 70 days, the best-corrected visual acuity was 20/25, with persistent small corneal opacity.

Conclusions and importance

Here, we report a case of fungal keratitis caused by Nigrospora oryzae. Microbiological identification of the causes of rare infections is difficult in clinical laboratories, necessitating the use of advanced molecular techniques based on amplification and sequencing of appropriate phylogenetic markers. Nigrospora oryzae responds to topical voriconazole and natamycin.

Post-Keratoplasty Microbial Keratitis in the Era of Lamellar Transplants-A Comprehensive Review

Microbial keratitis in a post-transplant cornea should be considered a distinct entity from microbial keratitis in a non-transplant cornea. Firstly, the use of immunosuppressive treatments and sutures in corneal transplants changes the etiology of keratitis. Secondly, corneal transplant has an impact on corneal biomechanics and structure, which facilitates the spread of infection. Finally, the emergence of lamellar transplants has introduced a new form of keratitis known as interface keratitis. Given these factors, there is a clear need to update our understanding of and management strategies for microbial keratitis following corneal transplantation, especially in the era of lamellar transplants. To address this, a comprehensive review is provided, covering the incidence, risk factors, causes, and timing of microbial keratitis, as well as both clinical and surgical management approaches for its treatment in cases of penetrating and lamellar corneal transplants.

Clinical outcomes and prognostic factors in Acanthamoeba keratitis

PURPOSE

To report clinical findings and prognostic factors for visual and morphological outcomes in patients with Acanthamoeba keratitis (AK).

METHODS

Single-center, retrospective, longitudinal study of 51 cases of AK diagnosed by real-time polymerase chain reaction (RT-PCR) between March 2010 and October 2022. The primary outcome was the final best corrected visual acuity (BCVA). Poor visual outcome was defined as a final BCVA ≥ 1 logMAR unit, while good visual outcome was defined as a final BCVA < 1 logMAR unit. Eyes from these two groups were compared, regarding demographic and initial clinical variables, anti-Acanthamoeba treatment used, and complications of the disease. Early diagnosis was defined as ≤ 14 days from symptom onset to diagnostic confirmation and initiation of Acanthamoeba medical treatment. Multivariable logistic regression was used to determine predictors of poor visual outcome.

RESULTS

A total of 51 eyes from 46 patients diagnosed with AK, all contact lens (CL) wearers, were included in this study. Average follow-up was 39.0 ± 30.2 [total range 14-120] months. Thirty-one eyes (60.8 %) presented good visual outcome, with a lower baseline age (30.5 ± 9.0 vs. 42.3 ± 15.8; p = 0.020), better initial BCVA (0.8 ± 0.7 logMAR units vs. 1.3 ± 0.9 logMAR units; p = 0.047), higher rate of early diagnosis (45.2 % vs. 5.6 %; p = 0.004), and higher rate of therapeutic epithelial debridement (64.5 % vs. 10 %; p < 0.001). 20 eyes (39.2 %) presented poor visual outcome, with 12 eyes undergoing evisceration/enucleation (23.5 %). These 20 eyes presented a higher rate of complications (90 % vs. 61.3 %; p = 0.031). In multivariable analysis, early diagnosis of AK (OR 19.78; 95 % CI 2.07-189.11; p = 0.010) and therapeutic epithelial debridement (OR 19.02; 95 % CI 3.27-110.57; p = 0.001) were associated with a good visual outcome.

CONCLUSIONS

In the present study, poor visual outcome was present in 39 % of affected eyes. Early AK diagnosis (≤14 days from symptom onset) and therapeutic epithelial debridement were associated with good final visual outcome.

Steroids in the Management of Infectious Keratitis

PURPOSE

To summarize the evidence base on the use of topical corticosteroids for infectious keratitis.

METHODS

Narrative review.

RESULTS

Infectious keratitis is a painful condition that often results in visually significant corneal stromal scarring, even when antimicrobial therapy is successful. Corticosteroids may reduce inflammation and subsequent scar formation and while relieving the acute ocular pain associated with a corneal ulcer. However, corticosteroids also reduce the host immune response, which could hinder the ability to clear infection. The safety and effectiveness of corticosteroids depends to a large part on the efficacy of the antimicrobials being used to treat the underlying infection. Randomized trials have found that corticosteroids are safe and effective for herpetic keratitis when used with appropriate antiviral therapy, and are safe for bacterial keratitis when used with broad spectrum topical antibiotics. The effectiveness of corticosteroids for bacterial keratitis has not been shown conclusively, although more advanced bacterial corneal ulcers may do better with corticosteroids. No randomized trials have assessed the safety and effectiveness of steroids for fungal or acanthamoeba keratitis. Animal studies suggest corticosteroids may be harmful in fungal keratitis, and observational human studies have found that steroids are harmful for fungal and acanthamoeba keratitis when started prior to anti-amoebics.

CONCLUSIONS

Topical corticosteroids, when used as an adjunct to antimicrobial therapy, may be beneficial if the antimicrobial being used can effectively clear or suppress the infection, such as in bacterial and herpetic keratitis. Randomized trials would be helpful to further delineate the role of corticosteroids for infectious keratitis.

Case Series of Rare Fungal Keratitides: Experiences from a Quaternary Eye Hospital in Sydney, Australia

The present article reports on the management of six different and rare cases of fungal keratitides, two of which have never been documented in previous literature. This is a case series of six patients with rare fungal keratitides managed at a quaternary eye referral unit, Sydney Eye Hospital, Australia over a period of 7 months (May to December, 2022). The order of occurrence of fungi isolated was Scedosporium apiospermum, Lomenstospora prolificans, Cladosporium spp., Paecilomyces, Syncephalastrum racemosum and Quambalaria spp. A combination of medical and surgical interventions was employed, including topical and systemic anti-fungal therapy, with one requiring therapeutic penetrating keratoplasty and another eventuating in evisceration. Two patients were successfully treated with corneal debridement and two others required pars plana vitrectomy with anterior chamber washout. It is important to remain vigilant with monitoring patient symptoms and correlating with clinical signs to guide antifungal therapy even in the context of confirmed culture and sensitivity results.

Use of Topical Cyclosporine 0.1% in Therapeutic Penetrating Keratoplasty for Fungal Keratitis

PURPOSE

The efficacy and safety of topical cyclosporine 0.1% in preventing early graft failure after therapeutic penetrating keratoplasty (TPK) in eyes with fungal keratitis were evaluated.

METHODS

This prospective case series included patients with fungal keratitis undergoing TPK from May to December 2019 who were treated with cyclosporine A 0.1% eye drops (tCSA group). We compared the outcome with a historical cohort of patients who were treated conventionally (CT group) with topical prednisolone acetate 1% eye drops started 3 weeks after surgery.

RESULTS

There were 20 patients (male: 13; female: 7) in the tCSA group and 28 patients in the CT group (male: 23; female: 5). The number of clear grafts 3 months postoperatively was 10 (50%) in the tCSA group and 4 (14.3%) in the CT group ( P = 0.011). The mean logarithm of the minimum angle of resolution best-corrected visual acuity was 1.49 ± 0.74 in the tCSA group and 2.10 ± 0.62 in the CT group ( P = 0.003). There were 5 patients (17.9%) with recurrence of the primary fungal infection in the CT group, 4 of whom were using topical prednisolone. There was no recurrence in the tCSA group. A logistic regression analysis revealed higher odds of a clear graft at 3 months postoperatively with topical cyclosporine 0.1% [odds ratio: 14.35 (95% confidence interval, 2.38-86.5), P = 0.004].

CONCLUSIONS

Postoperative treatment with topical cyclosporine 0.1% seems to increase graft survival and postoperative vision with reduced risk of recurrence of primary infection in eyes with fungal keratitis undergoing TPK.

Corticosteroids in the Management of Infectious Keratitis: A Concise Review

Microbial keratitis is devastating corneal morbidity with a variable spectrum of clinical manifestations depending on the infective etiology. Irrespective of the varied presentation delayed treatment can lead to severe visual impairment resulting from corneal ulceration, possible perforation, and subsequent scarring. Corticosteroids with a potent anti-inflammatory activity reduce host inflammation, thus minimizing resultant scarring while improving ocular symptoms. These potential effects of corticosteroids have been applied widely to treat various corneal diseases ranging from vernal keratoconjunctivitis to dry eye disease. However, antimicrobial therapy remains the mainstay of treatment in microbial keratitis, whereas the use of adjunctive topical corticosteroid therapy remains a matter of debate. Understandably, the use of topical corticosteroids is a double-edged sword with pros and cons in the treatment of microbial keratitis. Herein we review the rationale for and against the use and safety of topical corticosteroids in the treatment of infective keratitis. Important considerations, including type, dose, efficacy, the timing of initiation of corticosteroids, use of concomitant antimicrobial agents, and duration of corticosteroid therapy while prescribing corticosteroids for microbial keratitis, have been discussed. This review intends to provide new insights into the therapeutic utility of steroids as adjunctive treatment of corneal ulcer.

Topical Corticosteroids and Fungal Keratitis: A Review of the Literature and Case Series

The management of fungal keratitis is complex since signs and symptoms are subtle and ocular inflammation is minimal in the preliminary stages of infection. Initial misdiagnosis of the condition and consequent management of inflammation with corticosteroids is a frequent occurrence. Topical steroid use is considered to be a principal factor for development of fungal keratitis. In this review, we assess the studies that have reported outcomes of fungal keratitis in patients receiving steroids prior to diagnosis. We also assess the possible rebound effect present when steroids are abruptly discontinued and the clinical characteristics of three patients in this particular clinical scenario. Previous reports and the three clinical descriptions presented suggest that in fungal keratitis, discontinuing topical steroids can induce worsening of clinical signs. In these cases, we recommend to slowly taper steroids and continue or commence appropriate antifungal therapy.

Topical Corticosteroids for Infectious Keratitis Before Culture-Proven Diagnosis

Purpose

In clinical practice we sometimes encounter patients with severe corneal ulcers who have been treated with topical corticosteroids. This study reviewed the clinical features and visual outcomes of these patients and investigated the background of the prescription of topical corticosteroids.

Patients and Methods

The medical records of patients who visited the Cornea Service at Fujita Health University Bantane Hospital and were treated for infectious keratitis from April 2016 to March 2020 were retrospectively reviewed. Patients treated with topical corticosteroids before a culture-proven diagnosis were studied in terms of demographics, best-corrected visual acuity at arrival and at last visit, the clinical course after visit, ocular history, and combination therapy by the previous ophthalmologist.

Results

Out of the 200 eyes of 197 patients with infectious keratitis, 14 eyes of 14 patients were treated with topical corticosteroids before a culture-proven diagnosis. All 14 patients were referred, as they had severe keratitis that could not be cured with topical antibiotics and corticosteroids. Based on the culture results, we diagnosed Acanthamoeba keratitis (AK) in six patients, fungal keratitis (FK) in two patients, bacterial keratitis (including a suspected case) in two patients, and unknown cause in four patients. Two patients with AK, FK, and unknown keratitis had unfortunate clinical courses and poor visual outcomes. From the information in the referral letters, at least six of the 14 patients were treated with either acyclovir ocular ointment or valaciclovir tablets, along with topical corticosteroids.

Conclusion

Application of topical corticosteroids for keratitis that does not respond to empirical antibiotic therapy is harmful since AK or FK is likely involved in these topical antibiotic-resistant cases. Microbiological evidence, as well as a differential diagnosis of herpetic stromal keratitis, is needed when prescribing topical corticosteroid for the treatment of suspected infectious keratitis.

Clinical analysis of microbiologically proven fungal keratitis according to prior topical steroid use: a retrospective study in South Korea

Background

To compare the clinical characteristics and treatment outcomes of microbiologically proven fungal keratitis between users and non-users of prior topical steroids (PS and NPS, respectively).

Methods

Eighty-three cases with microbiologically proven fungal keratitis between January 2000 and December 2016 were reviewed retrospectively. Diagnosis of fungal keratitis was made through potassium hydroxide smear, culture, PCR, or biopsy. Baseline epidemiology, predisposing factors, clinical characteristics, microbiological profiles, and treatment outcomes were evaluated and compared between the PS and NPS groups. Treatment failure was defined as any case with complications or requiring surgery. The risk factors for treatment failure were evaluated using multivariate logistic regression in the overall cohort.

Results

A total of 30 cases with PS group and 53 cases with NPS group were included. Of these, sixteen fungal isolates were identified in the PS group and 14 isolates in the NPS group. Candida was the most common organism in both groups (6 cases, respectively), while Aspergillus (4 cases) was found only in the PS group (p = 0.103). No significant differences were observed in the mean age, sex, occupational distribution, epithelial defect size, hypopyon, and presenting best-corrected visual acuity (BCVA) between the two groups. Differences were observed between the PS and NPS groups in terms of previous ocular surface disease (OSD) (43.3% vs. 22.6%, p = 0.048) and deep infiltration (53.3% vs. 32.1%, p = 0.057). Regarding treatment outcomes, final BCVA < 0.1 (60% vs. 44.2%, p = 0.133), the use of voriconazole (topical 10% vs. 0%, p = 0.044; systemic 23.3% vs. 1.9%, p = 0.003), surgical intervention (43.3% vs. 20.8%, p = 0.029), and treatment failure (46.7% vs. 22.6%, p = 0.023) were more common in the PS group than in the NPS group. The significant risk factors for treatment failure were hypopyon (odds ratio [OR] 6.01, p = 0.005) and deep infiltration (OR 4.38, p = 0.013).

Conclusions

Previous OSD and deep infiltration were more common in the PS group compared to the NPS group. The PS group also experienced worse disease progression and treatment outcomes. These results highlight the need for paying attention to the use of steroids in clinical practice.

Clinical analysis of fungal keratitis in patients with and without diabetes

We compared the clinical characteristics, treatments, and prognoses of fungal keratitis in patients with and without diabetes. Patients diagnosed with fungal keratitis at Shandong Eye Institute between January 2010 and December 2016 were retrospectively reviewed and classified as diabetic and nondiabetic groups. One-hundred-and-eleven patients (111 eyes) with diabetes and 740 patients (740 eyes) without diabetes were included. The diabetic patients showed significantly older (p< 0.05) and lower male:female ratio (p<0.05). Plants trauma was the primary risk factor in both groups, and there was no significant difference of pathogen type (the most common was Fusarium genus, followed by Alternaria and Aspergillus genera). Multivariate logistic regression analyses revealed that diabetes and topical glucocorticoid use were the independent risk factors for the severity of fungal keratitis. The recurrent infection rate between the diabetic and nondiabetic patients during the follow-up (6 to 24 months) after penetrating keratoplasty (PKP) was not significantly different. Although the recurrent epithelial defect, rejection, and best-corrected visual acuity were similar between the patients with matched bed/graft size (7.75/8.0 mm) in the two groups 1 year after PKP, the incidence of delayed re-epithelialization (>7 days) was significantly higher in diabetic patients (3/10 versus 2/43 in nondiabetic patients, p<0.05). More specially, the diabetic patients with the duration ≥10 years showed more significantly delayed re-epithelialization than those with the diabetic duration less than 10 years (3/5 versus 1/26, p<0.05). In conclusion, the diabetes mellitus is an independent risk factor that affect the severity of fungal keratitis. Corneal re-epithelialization was significantly delayed after PKP in the diabetic patients, especially with the duration ≥10 years.

Effect of itraconazole on the cornea in a murine suture model and penetrating keratoplasty model

AIM

To investigate the anti-(lymph)angiogenic and/or anti-inflammatory effect of itraconazole in a corneal suture model and penetrating keratoplasty (PK) model.

METHODS

Graft survival, corneal neovascularization, and corneal lymphangiogenesis were compared among itraconazole, amphotericin B, dexamethasone, phosphate buffered saline (PBS) and surgery-only groups following subconjunctival injection in mice that underwent PK and corneal suture. Immunohistochemical staining and analysis were performed in each group. Real-time polymerase chain reaction (RT-PCR) was performed to quantify the expression of inflammatory cytokines (TNF-alpha, IL-6) and vascular endothelial growth factor (VEGF)-A, VEGF-C, VEGFR-2, and VEGFR-3.

RESULTS

In the suture model, the itraconazole group showed less angiogenesis, less lymphangiogenesis, and less inflammatory infiltration than the PBS group (all P<0.05). The itraconazole group showed reduced expression of VEGF-A, VEGFR-2, TNF-alpha, IL-6 than the PBS group (all P<0.05). In PK model, the two-month graft survival rate was 28.57% in itraconazole group, 62.50% in dexamethasone group, 12.50% in PBS group, 0 in amphotericin B group and 0 in surgery-only group. Graft survival in the itraconazole group was higher than that in the amphotericin, PBS and surgery-only group (P=0.057, 0.096, 0.012, respectively). The itraconazole group showed less total angiogenesis and lymphangiogenesis than PBS group (all P<0.05).

CONCLUSION

Itraconazole decrease neovascularization, lymphangiogenesis, and inflammation in both a corneal suture model and PK model. Itraconazole has anti-(lymph)-angiogenic and anti-inflammatory effects in addition to its intrinsic antifungal effect and is therefore an alternative treatment option in cases where steroids cannot be used.

Inflammation and oxidative stress in corneal tissue in experimental keratitis due to Fusarium solani: Amelioration following topical therapy with voriconazole and epigallocatechin gallate

Combined antifungal and antioxidant therapy may help to reduce oxidative stress in fungal keratitis. Experimental Fusarium solani keratitis was induced by application of F. solani conidia to scarified cornea (right eye) of 16 rabbits (another four rabbits were negative controls [Group I]). Five days later, F. solani-infected animals began receiving hourly topical saline alone (Group II), voriconazole (10 mg/mL) alone (Group III), epigallocatechin gallate (EGCG, 10 mg/mL) alone (Group IV) or voriconazole and EGCG (Group V). Twenty days post-inoculation, corneal lesions were graded. After animal sacrifice, excised corneas underwent histopathological and microbiological investigations. Corneal tissue levels/activities of interleukin 1 beta (IL-1β) and tumour necrosis factor alpha (TNF-α) gene mRNA transcripts, matrix metalloproteinase (MMP) 2 and 9 proteins, malondialdehyde (MDA) and reduced glutathione (GSH), and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), were also measured. Clinical and histopathological scores (severity of corneal lesions; [P < .05]) and mean levels (P < .05) of IL-1β and TNF-α mRNA transcripts, MMP 2, MMP 9 and MDA were Group II > Groups IV and III > Groups V and I. Mean SOD, CAT, GPx and GSH levels (P < .05) were Group II < Groups IV and III < Groups V and I. Topical voriconazole with EGCG apparently reduces inflammation in experimental F. solani keratitis, as manifested by improved clinical, histological, microbiological and molecular parameters.

The diagnosis and management of contact lens-related microbial keratitis

Contact lens-associated microbial keratitis poses a diagnostic dilemma for optometrists on two fronts. The distinction between sterile inflammation and microbial infection is often blurred. In addition, there is a requirement with nearly 50 per cent of the Australian and New Zealand optometric profession being therapeutically endorsed, to distinguish between cases of infection that can be managed in the community verses those that require escalation to public hospitals that have access to laboratory diagnostic tools and advanced imaging techniques, such as in vivo confocal microscopy. Pattern recognition and incorporation of knowledge of aetiology and risk factors assists optometrists to decide on optimal management strategies. Skilled optometrists will utilise emerging diagnostic and therapeutic technologies to ensure safe management strategies and better outcomes for these cases.

[The German Acanthamoeba keratitis register: Initial results of a multicenter study]

BACKGROUND AND PURPOSE

In September 2011 the cornea section of the German Ophthalmological Society (DOG) established the first German Acanthamoeba keratitis registry. The data of this multicenter survey are being collected, compiled and evaluated at the Department of Ophthalmology at the Saarland University. The aim of this article is to present an intermediate report.

PATIENTS AND METHODS

Data from 172 eyes with Acanthamoeba keratitis were collected during the last 10 years. For this interim report we actually evaluated 121 eyes (60.2 % female patients, average age 41.3 years) and collected the following data: date of onset of symptoms, date and method of diagnosis, initial diagnosis, anamnestic data, clinical symptoms and signs at diagnosis and during follow-up, conservative and surgical therapy. Criteria for inclusion in the Acanthamoeba registry was the established diagnosis of an Acanthamoeba keratitis with at least one of the methods described in this article.

RESULTS

Acanthamoeba keratitis could be histologically proven in 55.3 % of the cases, via PCR in 25.6 %, with confocal microscopy in 20.4 % and using in vitro cultivation in 15.5 %. Clinical symptoms and signs in Acanthamoeba keratitis were pain in 67.0 %, ring infiltrates in 53.4 %, pseudodendritiform epitheliopathy in 11.7 % and keratoneuritis in 5.8 %. In 47.6 % of the cases the initial diagnosis was herpes simplex virus keratitis followed by bacterial keratitis in 25.2 % and fungal keratitis in 3.9 %. Acanthamoeba keratitis was the correct initial diagnosis in only 23.2 % of cases. The average time period between first symptoms and diagnosis was 2.8 ± 4.0 months (range 0-23 months). A triple therapy with Brolene® Lavasept® and antibiotic eye drops at least 5 ×/day was used in 54.5 % of eyes (n = 66). Penetrating keratoplasty was performed in 40.4 %, in 18 cases in combination with cryotherapy of the cornea. The mean graft diameter was 7.9 ± 1.1 mm (range 3.5-11.0 mm). The final visual acuity (Snellen visual acuity chart at 5 m) was comparable in the two groups of eyes with (5/40 ± 5/25) and without (5/32 ± 5/25) keratoplasty.

CONCLUSION

Acanthamoeba keratitis is a rare and often very late diagnosed disease and two thirds of the cases were initially misdiagnosed. The early recognition of the typical symptoms is crucial for the prognosis of the disease. All ophthalmological departments in Germany are invited to submit further data of all confirmed cases (berthold.seitz@uks.eu), whether retrospectively or prospectively in order to generate an adequate standardized diagnostic and therapeutic approach for this potentially devastating disease.

The Impact of Topical Corticosteroids Used in Conjunction with Antiamoebic Therapy on the Outcome of Acanthamoeba Keratitis

PURPOSE

To examine the impact of topical corticosteroid use after the start of antiamoebic therapy (AAT) on the outcomes of Acanthamoeba keratitis (AK) therapy.

DESIGN

Cohort study.

PARTICIPANTS

A total of 196 patients diagnosed with AK at Moorfields Eye Hospital, London, between January 1991 and April 2012. In 13 patients with bilateral AK, 1 eye was randomly excluded from analysis.

METHODS

Patient demographics and clinical examination findings were collected both at the start of AAT and subsequently at the time that topical corticosteroid therapy was initiated. Preliminary a priori investigations were used to identify effect modifiers/confounders and extreme associations requiring consideration in multivariate regression modeling. A multivariable logistic model, optimized for assessment of corticosteroid use after the start of AAT, was used to estimate the odds ratios (ORs) of a suboptimal outcome.

MAIN OUTCOME MEASURES

Suboptimal outcome was defined as final visual acuity ≤20/80, corneal perforation, or the need for keratoplasty.

RESULTS

In multivariable analysis, restricted to 129 eyes (1 eye per patient) free of scleritis and hypopyon at the start of AAT, topical corticosteroids were not associated with worse outcomes (OR, 1.08; 95% confidence interval [CI], 0.39-3.03), even when corticosteroids had been used before the start of AAT. Risk factors significantly associated with worse outcomes were topical corticosteroid use before the start of AAT (OR, 3.85; 95% CI, 1.35-11.03), a corneal ring infiltrate (together with at least 1 other feature of AK) present at the start of AAT (OR, 5.89; 95% CI, 1.17-29.67), and age ≥33 years at the start of AAT (OR, 4.02; 95% CI, 1.46-11.06).

CONCLUSIONS

Many corneal specialists currently are uncertain about the risk benefit associated with the use of topical corticosteroids for the management of inflammatory complications of AK. The evidence from this study gives clinicians and patients reassurance that the potential benefits of topical corticosteroid therapy, for treating pain and discomfort, are not associated with worse outcomes when initiated after starting modern AAT. Other potential benefits, in terms of resolution of inflammatory complications, will not be demonstrated without a carefully designed randomized clinical trial.

Levofloxacin and Tobramycin for Severe Bacterial Keratouveitis

PURPOSE

To report on clinical features and outcome of severe bacterial keratouveitis.

METHODS

Twenty patients with severe bacterial keratouveitis treated with topical tobramycin and levofloxacin and oral levofloxacin were included. Main outcome measures were ulcers location, bacterial isolates, risk factors, visual prognosis.

RESULTS

Centrally located ulcer/abscess was present in 65% of patients. Contact lens (CL) wear was the most common risk factor (70%). Bacterial isolates were observed in 58% of patients, none resistant to tobramycin and levofloxacin. Pseudomonas aeruginosa was found in 47% of positive cases and in 64% of CL wearers. After therapy, the mean visual acuity improved significantly (p < 0.0001), particularly in contact lens wearers (p = 0.04) and in patients younger than 60 years old (p < 0.001).

CONCLUSIONS

Pseudomonas aeruginosa is the most frequent cause of bacterial keratouveitis and CL wear the most common risk factor. Topical tobramycin and levofloxacin and oral levofloxacin are effective in the treatment of bacterial keratouveitis.

[Purulent corneal ulcers: clinical presentation, diagnosis, and conservative treatment]

This is a detailed review of purulent corneal ulcer signs and symptoms, problems in diagnosis, and conservative treatment options.

Combined anterior chamber washout, amniotic membrane transplantation, and topical use of corticosteroids for severe peripheral ulcerative keratitis

PURPOSE

The aim of this study was to evaluate the efficacy of anterior chamber washout, amniotic membrane transplantation, and topical use of corticosteroids in the treatment of severe peripheral ulcerative keratitis with membranous endothelial exudation.

METHODS

Twelve patients (12 eyes) with severe corneal ulceration were included. All ulcers were located at the corneal periphery, accompanied by central corneal epithelial defects and stromal edema. Membranous endothelial exudates were observed by anterior segment optical coherence tomography. The duration of the ulcers was 1 to 10 months (mean, 3.0 ± 2.9 months) before the patients visited our institution. Corneal inflammation and ulceration could not be controlled after 2 weeks of topical antiinflammation treatment. Bacterial, fungal, and Acanthamoeba infections were not detected. Surgical treatment was performed. After the necrotic corneal tissue was cut, exudation clinging to the endothelium was removed. Then, amniotic membrane was placed on the corneal lesion. Postoperatively, corticosteroid eye drops and topical and systemic antiinflammation medication were given. Healing of corneal ulcers and improvement of stromal edema were detected by slit-lamp microscopy. All patients were followed up for 3 to 15 months (mean, 6.5 ± 3.7 months).

RESULTS

All corneal ulcers healed by 1 to 2 weeks after surgery. The corneal stromal edema subsided within 1 month. All patients achieved a stable ocular surface. There was no recurrence during the follow-up.

CONCLUSIONS

Anterior chamber washout and amniotic membrane transplantation combined with topical corticosteroids seems to be effective for the treatment of severe peripheral ulcerative keratitis with endothelial exudates.

Early addition of topical corticosteroids in the treatment of bacterial keratitis

IMPORTANCE

Scarring from bacterial keratitis remains a leading cause of visual loss.

OBJECTIVE

To determine whether topical corticosteroids are beneficial as an adjunctive therapy for bacterial keratitis if given early in the course of infection.

DESIGN, SETTING, AND PARTICIPANTS

The Steroids for Corneal Ulcers Trial (SCUT) was a randomized, double-masked, placebo-controlled trial that overall found no effect of adding topical corticosteroids to topical moxifloxacin hydrochloride in bacterial keratitis. Here, we assess the timing of administration of corticosteroids in a subgroup analysis of the SCUT. We define earlier administration of corticosteroids (vs placebo) as addition after 2 to 3 days of topical antibiotics and later as addition after 4 or more days of topical antibiotics.

MAIN OUTCOMES AND MEASURES

We assess the effect of topical corticosteroids (vs placebo) on 3-month best spectacle-corrected visual acuity in patients who received corticosteroids or placebo earlier vs later. Further analyses were performed for subgroups of patients with non-Nocardia keratitis and those with no topical antibiotic use before enrollment.

RESULTS

Patients treated with topical corticosteroids as adjunctive therapy within 2 to 3 days of antibiotic therapy had approximately 1-line better visual acuity at 3 months than did those given placebo (-0.11 logMAR; 95% CI, -0.20 to -0.02 logMAR; P = .01). In patients who had 4 or more days of antibiotic therapy before corticosteroid treatment, the effect was not significant; patients given corticosteroids had 1-line worse visual acuity at 3 months compared with those in the placebo group (0.10 logMAR; 95% CI, -0.02 to 0.23 logMAR; P = .14). Patients with non-Nocardia keratitis and those having no topical antibiotic use before the SCUT enrollment showed significant improvement in best spectacle-corrected visual acuity at 3 months if corticosteroids were administered earlier rather than later.

CONCLUSIONS AND RELEVANCE

There may be a benefit with adjunctive topical corticosteroids if application occurs earlier in the course of bacterial corneal ulcers.

The impact of topical corticosteroid use before diagnosis on the outcome of Acanthamoeba keratitis

OBJECTIVE

To examine the impact of topical corticosteroid use before the diagnosis of Acanthamoeba keratitis (AK) on final visual outcomes and to determine the prognostic factors predicting poorer outcomes.

DESIGN

Cohort study.

PARTICIPANTS

A total of 209 eyes of 196 patients with retrievable medical records, diagnosed with AK at Moorfields Eye Hospital, London, between January 1991 and April 2012. One eye was randomly excluded from analysis in the 13 cases of bilateral AK.

METHODS

Patient demographic, initial clinical examination findings, and management details were collected. The outcomes of patients treated with topical corticosteroids before diagnosis of AK were compared with those not treated with topical corticosteroids before diagnosis. A multivariable logistic model, optimized for prior corticosteroid use, was used to derive the odds ratios (ORs) of a suboptimal visual outcome.

MAIN OUTCOME MEASURES

Suboptimal visual outcome was defined as final visual acuity (VA) ≤ 20/80, corneal perforation, or need for keratoplasty.

RESULTS

Acanthamoeba keratitis was diagnosed on microbiological culture in 94 eyes (48.0%), on histopathologic examination in 27 eyes (13.8%), on confocal microscopy in 38 eyes (19.4%), and on the basis of a typical clinical course and response to treatment in 37 eyes (18.9%). Final VA and prior corticosteroid use data were available for 174 eyes (88.8%). In multivariable analysis, corticosteroid use before diagnosis was associated with suboptimal visual outcome (OR, 3.90; 95% confidence interval [CI], 1.78-8.55), as were disease stage 3 at presentation (OR, 5.62; 95% CI, 1.59-19.80) and older age (60+ years) at diagnosis (OR, 8.97; 95% CI, 2.13-37.79).

CONCLUSIONS

Corticosteroid use before diagnosis of AK is highly predictive of a poorer visual outcome. This is largely due to the initial misdiagnosis of AK as herpetic keratitis. It is important to include AK in the differential diagnosis of keratitis in all contact lens users with keratitis, particularly before making a diagnosis of herpes keratitis and before the use of topical corticosteroids in the therapy of any indolent keratitis.

Diversity of microbial species implicated in keratitis: a review

Background:

Microbial keratitis is an infectious disease of the cornea characterised by inflammation and is considered an ophthalmic emergency requiring immediate attention. While a variety of pathogenic microbes associated with microbial keratitis have been identified, a comprehensive review identifying the diversity of species has not been completed.

Methods:

A search of peer-reviewed publications including case reports and research articles reporting microorganims implicated in keratitis was conducted. Search engines including PubMed, Scopus and Web of Science with years ranging from 1950-2012 were used.

Results:

232 different species from 142 genera, representing 80 families were found to be implicated in microbial keratitis. Fungi exhibited the largest diversity with 144 species from 92 genera. In comparison, 77 species of bacteria from 42 genera, 12 species of protozoa from 4 genera and 4 types of virus were identified as the infectious agents. A comparison of their aetiologies shows reports of similarities between genera.

Conclusions:

The diversity of microbial species implicated in keratitis has not previously been reported and is considerably greater than suggested by incidence studies. Effective treatment is heavily reliant upon correct identification of the responsible microorganisms. Species identification, the risk factors associated with, and pathogenesis of microbial keratitis will allow the development of improved therapies. This review provides a resource for clinicians and researchers to assist in identification and readily source treatment information.

Non-viral microbial keratitis in children

Microbial (non-viral) keratitis is a serious vision-threatening condition. The management of microbial keratitis in children is particularly complicated by the children's inability to cooperate during examinations and the lack of information prior to presentation. Predisposing factors vary according to geographical location and age. Corneal trauma is the leading cause for microbial keratitis in children, followed by systemic and ocular disease. Etiologic agents are most frequently Gram-positive and Gram-negative bacteria commonly found in contact lens-related microbial keratitis. Mycotic keratitis is a major risk factor in tropical weather conditions, particularly when associated with agricultural trauma. Early diagnosis, intensive drug treatment, and timely planned surgical intervention may effectively improve the outcome of pediatric microbial keratitis.

Comparison of antibiotic-only and antibiotic-steroid combination treatment in corneal ulcer patients: double-blinded randomized clinical trial

OBJECTIVE

To determine the benefit of early addition of corticosteroids to antibiotics in the treatment of corneal ulcers.

DESIGN

Randomized clinical trial.

PARTICIPANTS

Thirty eyes of 30 patients, over the age of 12 years, with bacterial corneal ulcer confirmed by culture.

METHODS

Patients were randomized before enrollment; 15 were treated with gatifloxacin (Zymar) and a masked placebo and the other 15 were treated with gatifloxacin and masked dexamethasone 0.1% (Maxidex). Primary outcome was residual ulcer size at 10 weeks based on digital photographs. Secondary outcomes included residual ulcer area by clinician estimate, visual acuity, VF-14 score, and time to healing.

RESULTS

All subjects (n = 30) demonstrated a reduction in ulcer size over the study period. There was no significant difference between the 2 groups in terms of the primary outcome. There was a significant difference between the 2 groups in 1 of the secondary outcomes. The mean residual ulcer size compared with the baseline by clinician estimate (slit-lamp) was -0.789 mm2 for the antibiotic-only group and -4.206 mm2 for the antibiotic-steroid group (p = 0.05). Among the other secondary outcomes there were no significant differences between the 2 groups.

CONCLUSIONS

No benefit was demonstrated in our primary outcome for using steroids in combination with antibiotic therapy in treatment of corneal ulcers. This study suggests that the early addition of steroids to the antibiotic treatment of corneal ulcers does not seem to be harmful when employed in a closely monitored clinical setting.

Update on fungal keratitis from 1999 to 2008

PURPOSE

To report trends in fungal keratitis from a single institution between 1999 and 2008.

METHODS

Retrospective chart review of the patients presenting to the cornea service with fungal keratitis from April 1999 to December 2008.

RESULTS

Seventy-eight eyes of 76 patients were identified. The most common predisposing factors included contact lens use (35.9%), trauma (21.8%), and history of penetrating keratoplasty (15.4%). There was a significant increase in the rate of contact lens-related Fusarium infections over time, which peaked in 2005 and 2006 (P = 0.021). Almost 40% of fungal keratitis cases [11 of 28 eyes (39.3%)] were soft contact lens-related Fusarium infections in 2005 and 2006, and this decreased to less than 10% [2 of 25 eyes (8%)] in 2007 and 2008. The odds of having a contact lens-related Fusarium infection in 2005-2006 compared with 2007-2008 was 4.40 (95% confidence interval of 0.60-32.50) (P = 0.178). Despite the decrease in contact lens-related Fusarium infections, the number of fungal infections remained elevated in 2007 (10 eyes) and 2008 (14 eyes), including contact lens-related infections (3 in 2007 and 6 in 2008).

CONCLUSIONS

A definite increase in the number of fungal keratitis cases began in 2004 and continued through 2006 during the Fusarium outbreak associated with ReNu with MoistureLoc. Despite the decrease in contact lens-related Fusarium infections, the overall number of fungal keratitis cases remained high through 2008. Fungal keratitis was more often associated with contact lens use than with trauma in this time.

Surgical outcomes in cases of contact lens-related Fusarium keratitis

OBJECTIVES

To examine seven cases of contact lens-related Fusarium keratitis that resulted in therapeutic penetrating keratoplasty, to investigate which factors were associated with favorable versus poor graft outcome in this population.

METHODS

Seven patients who underwent corneal transplant after contact lens-related, culture-proven Fusarium keratitis were identified through a retrospective chart review. The cases occurred between September 2005 and January 2006 at the University of Medicine and Dentistry of New Jersey and Wills Eye Hospital. All seven patients had used Bausch and Lomb's ReNu with MoistureLoc. The outcomes studied were graft status, infection recurrence, and 6-month postoperative visual acuity.

RESULTS

The rejection rate was 57.1% and the recurrence rate was 28.6% in this study. No eyes were lost to fungal endophthalmitis. In this population, larger ulcer size and a greater total number of medical agents used before and after penetrating keratoplasty were significantly associated with poor outcomes, namely graft rejection and poor visual acuity. In addition, it was noted that the patients who suffered recurrence of infection had both a larger median graft size and a longer median duration of postoperative antifungal use although these results did not reach statistical significance.

CONCLUSIONS

Larger ulcer size, larger graft size, a greater number of medical agents used, and a longer duration of postoperative antifungal therapy may be useful parameters in predicting surgical outcomes in patients with fungal keratitis. Further research is needed to validate our results and to elucidate the mechanisms behind graft rejection in the setting of fungal keratitis.

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.

Therapie und Prognose der bakteriellen Keratitis

This review discusses the current therapy for bacterial keratitis, especially that using quinolones of the fourth generation. In addition, the importance of additive steroids is discussed. Steroids should be administered at a low dose and tapered off slowly, whereas antibiotics should be applied at a high dosage and discontinued abruptly.

Fungal Keratitis: Emerging Trends and Treatment Outcomes

PURPOSE

To review the trends, risk factors, causative organisms, treatment, and outcomes of fungal keratitis at the authors' institution.

METHODS

A retrospective review of the records of consecutive patients diagnosed with fungal keratitis at the authors' institution from January 1999 to June 2006.

RESULTS

Eighty-four patients were diagnosed with fungal keratitis during this period. The average age of the patients was 48 years, and 64% were male. Until 2004, trauma (51%) and contact lens use (40%) were the major risk factors. After 2005, contact lens use (52%) surpassed trauma as the most common risk factor (29%). The percentage of fungal ulcers caused by nontherapeutic contact lenses increased from 21% between 1999 and 2001 to 32% between 2002 and 2004 and to 45% in 2005 and 2006. Eighty-six percent of cultured organisms were filamentous. Fusarium (41%) was the most commonly isolated genus, followed by Candida (14%), Curvularia (12%), and Aspergillus (12%). Visual acuity was worse than 20/200 in 56% of patients at presentation. Final visual acuity was 20/40 or better in 70% of patients treated with medication alone and 16% of patients requiring therapeutic keratoplasty. Surgical intervention in the acute phase was necessary in 23% of patients. Seventy-four percent of medically treated patients had dual topical antifungal therapy. Natamycin 5% and amphotericin B 0.15% were the most commonly used drugs.

CONCLUSIONS

Contact lenses are a major risk factor for fungal keratitis. The incidence of contact lens-related fungal keratitis was increasing even before the Fusarium outbreak in 2005 and 2006. Good visual outcomes can be achieved by aggressive dual topical antifungal therapy.

Infectious Keratitis Caused by Stenotrophomonas maltophilia and Yeast Simultaneously

PURPOSE

To report a case of coinfection of the human cornea by Stenotrophomonas maltophilia and yeast.

METHODS

A 59-year-old woman presented with a corneal ulcer. The corneal lesion worsened suddenly after initial improvement with empirical antibiotic treatment. A culture revealed S. maltophilia. The keratitis rapidly progressed despite treatment with sensitivity-proven antibiotic agents. Eventually, the patient underwent therapeutic penetrating keratoplasty.

RESULTS

Pathology of the cornea showed yeast forms and pseudohyphae scattered over the cornea. After surgery, the inflammation was controlled without any signs of recurrent infection.

CONCLUSION

Coinfection of the cornea by S. maltophilia and yeast may occur in a susceptible cornea and may not be controlled by standard medical treatment.