Emerging prevalence of microsporidial keratitis in Singapore: epidemiology, clinical features, and management.

OBJECTIVE: To investigate the incidence and epidemiologic factors involved in the development of microsporidial keratitis. The association of host immune status and clinical pattern, clinical features, and the role of fluoroquinolone monotherapy in treatment are also examined. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: All cases (124 patients, 134 eyes) of microsporidial keratitis confirmed with modified trichrome stain positive of corneal scrape over a 4-year period. METHODS: Epidemiologic factors were observed. Host immune status with human immunodeficiency virus (HIV) serology and CD4/CD8 analysis was performed when consent was obtained. Visual acuity (VA) and slit-lamp examination throughout the course of keratitis was recorded. Treatment used included topical fluoroquinolones (ciprofloxacin 0.3%, moxifloxacin 0.5%, gatifloxacin 0.5%, levofloxacin 0.5%, or norfloxacin 0.3%) as monotherapy or in combination with topical fumagillin and/or systemic albendazole. Where corneal edema developed, ultrasound corneal pachymetry was recorded. MAIN OUTCOME MEASURES: Demographic features and epidemiologic factors, including host immune status. Clinical features and disease course, including the response to different therapeutic regimes. RESULTS: Patients ranged in age from 11 to 68 years (mean, 31.9; median, 30) with a male:female ratio of 8:1 (females n = 17 [13.7%]). We performed HIV serology and CD4/CD8 in 45.9% of cases (n = 57); all the cases tested were negative with normal T-cell indices. Epidemiologic factors included soil exposure (50%), contact lens wear (21.1%), and topical steroid treatment (17.1%). The VA on presentation ranged from 20/20 to 20/100 (median, 20/30) with no loss in lines of VA on resolution. Common features were follicular papillary conjunctivitis and coarse punctate epithelial lesions in 3 patterns--diffuse, peripheral, and paracentral--evolving into nummular keratitis before resolution. Resolution occurred in 99% of cases on topical fluoroquinolone monotherapy. Four patients had recurrent disease that resolved with repeat fluoroquinolone or fluoroquinolone/oral albendazole combination. Two new clinical features were identified--diffuse endotheliitis (19.4%) with corneal edema and limbitis. CONCLUSIONS: This study identifies an increasing incidence of microsporidial keratitis in Singapore with a strong correlation with prior soil exposure. Diffuse endotheliitis and limbitis have not been described and resolves with topical steroid therapy. Topical fluoroquinolone monotherapy is a valid treatment option.

An outbreak of Fusarium keratitis associated with contact lens wear in Singapore.

CONTEXT: Fungal keratitis is a potentially blinding condition that is rarely seen with contact lens wear. OBJECTIVE: To describe a nationwide outbreak of fungal keratitis caused by Fusarium species among contact lens wearers in Singapore. DESIGN, SETTING, AND PATIENTS: Nationwide, hospital-based case series. All cases of fungal keratitis among contact lens wearers in all ophthalmology departments in Singapore were reviewed along with the charts of all contact lens wearers with culture-proven fungal keratitis from March 2005 through May 2006. A standardized telephone interview was conducted to obtain additional clinical information. MAIN OUTCOME MEASURE: Diagnosis of Fusarium keratitis associated with contact lens wear. RESULTS: During the study period, 66 patients (68 affected eyes) were diagnosed with Fusarium keratitis associated with contact lens wear; the estimated annual national incidence is 2.35 cases per 10,000 contact lens wearers (95% confidence interval, 0.62-7.22). Patients ranged in age from 13 to 44 years (mean [SD], 27.1 [8.4] years), of which 32 (48.5%) were men. The vast majority (65 patients; 98.5%) wore soft, disposable contact lenses; 62 patients (93.9%) reported using 1 brand of contact lens cleaning solution (ReNu, Bausch & Lomb, Rochester, NY), including 42 patients (63.6%) who recalled using ReNu with MoistureLoc. Most patients (81.8%) reported poor contact lens hygiene practices, including overnight use of daily wear contact lenses (19.7%), and use of contact lenses past the replacement date (43.9%). The final best-corrected visual acuity ranged from 20/20 to 20/80. Five patients (5 eyes; 7.4%) required emergency therapeutic or tectonic corneal transplantation. CONCLUSIONS: A new and evolving epidemic of Fusarium keratitis associated with contact lens wear was found in Singapore. Physicians and eye care practitioners worldwide need to be aware of the likelihood of similar outbreaks emerging among contact lens wearers.

Noninflammatory flap edema after laser in situ keratomileusis associated with asymmetrical preoperative corneal pachymetry.

PURPOSE: To report persistent unilateral flap edema following laser in situ keratomileusis (LASIK) in patients with asymmetrical central corneal thickness. SETTING: Minnesota Eye Consultants, Minneapolis, Minnesota. METHODS: Retrospective, noncomparative interventional case series. RESULTS: We examined 6 eyes of 3 patients with asymmetrical preoperative pachymetry who developed persistent unilateral flap edema after uneventful myopic LASIK in the eye with thicker preoperative pachymetry. All cases had asymmetrical preoperative pachymetry with flap edema developing in the eye with higher preoperative mean central corneal thickness (CCT) values, preoperative mean CCT subject eye 622 microm (range 556-664 microm) versus fellow eye 583 microm (range 510-621 microm). There was no associated ocular inflammation or rise in intraocular pressure. Significant flap edema resolved on a combination treatment of topical steroid and hypertonic saline. CONCLUSIONS: Laser in situ keratomileusis can cause temporary endothelial cell dysfunction or stress, which manifests as temporary flap edema and subclinical corneal thickening. The edema appears to be limited to the actual flap and there was no loss of epithelial integrity in these eyes and no clinically noticeable interface fluid. This new clinical entity appears to occur in patients with asymmetrical preoperative corneal pachymetry and is associated with postoperative specular microscopy abnormalities. In cases with unexplained asymmetrical corneal thickness, preoperative evaluation should include specular microscopy to evaluate for risk features that may increase the chances of a slower postoperative recovery.

Acanthamoeba keratitis associated with contact lens wear in Singapore.

PURPOSE: To describe an outbreak of Acanthamoeba keratitis (AK) cases among contact lens wearers. DESIGN: Retrospective cohort study. METHODS: Patients with AK were included. Relevant demographic and clinical data were obtained from case records, and patients were interviewed using a standardized questionnaire. Contact lens practices, including type of contact lens and solution used, were noted. In addition, clinical features at presentation, management, and clinical outcomes were recorded. RESULTS: Forty-two patients (affecting 43 eyes) treated between 2000 and 2007 were included. Diagnosis was made by microbiologic culture in 35 cases and by microbiologic and histologic analysis in 2 cases, whereas the remainder were diagnosed based on clinical features and response to treatment. There was a gradual increase in cases since 2005, with a sharp increase in 2007, when 8 local patients were treated. Of 30 patients where contact lens solution data were available, 18 reported using a Complete brand Multipurpose solution (Advanced Medical Optics, Santa Ana, California, USA) before the infection. Among resident cases treated since February 2006, 7 (63%) of 11 patients used a Complete brand solution. Suboptimal hygiene practices were found in all patients interviewed. Fifteen patients required corneal grafting, with 11 undergoing therapeutic deep lamellar keratoplasty (DLK), 2 undergoing optical penetrating keratoplasty (PK), 1 undergoing optical DLK, and 1 undergoing therapeutic PK. The remainder were treated successfully medically with combination antiamebic therapy. The average duration of therapy was 116.2 days (range, 15 to 283 days). Of patients with radial keratoneuritis with or without epithelial disease, 83.3% achieved final vision of 20/40 or better, whereas this was achieved in 41.7% of those with ring infiltrate. Twenty-five percent of patients with ring infiltrate had final visual acuity of counting fingers or worse, whereas no patient with keratoneuritis and epithelial disease had final vision worse than counting fingers. CONCLUSIONS: There was an increase in the number of contact lens users with AK seen in the major eye departments of Singapore. Most of our patients also reported using a Complete brand Multipurpose solution before infection, and this parallels a similar outbreak in the United States. Increasing severity of infection was associated with worse visual outcome.

Implementation and evaluation of an ophthalmic nurse practitioner emergency eye clinic.

BACKGROUND: To describe the implementation and assess the efficacy of an ophthalmic nurse practitioner (ONP) emergency eye clinic. METHODS: In a 13-month period, patients were assessed in an ONP emergency eye clinic in a teaching hospital setting. The ONP clinic was run on a defined scope of practice. Risk assessment was carried out in two audit sessions, 4 weeks duration each, at months 1 and 7. Patient outcomes were monitored for reattendance to the department following discharge. RESULTS: A total of 259 patients were assessed, 143 (55.2%) were within the scope of practice. In the two audit periods, concordance with the ophthalmologist was high, diagnosis 100% and management 95.2%. Many patients assessed (111, 42.9% of total) had minor external eye conditions--chiefly corneal foreign body or abrasion (n = 50), conjunctivitis (n = 14) and minor (non-alkali) chemical injuries (n = 11). No reattendance was noted in these patients when monitored for a mean of 12 months (range 7-19 months). CONCLUSIONS: This study demonstrates the safety and effectiveness of an ONP emergency eye clinic when practising within a defined scope of practice. An ONP-led emergency eye clinic is a viable addition to acute ophthalmic eye care in Australia.