Epidemiology of bacterial corneal ulcers at tertiary centres in Vancouver, B.C.

OBJECTIVE: To report the epidemiology of culture-positive bacterial corneal ulcers in Vancouver, B.C., Canada. DESIGN: Retrospective, observational case series. METHODS: Predetermined search terms were entered into the hospitals' electronic microbiology databases to create a cohort of patients who had undergone corneal scrapings for ulcers from April 2006 to March 2011. All specimens were plated on culture media. Cultured species were identified, and antimicrobial sensitivities were obtained. Clinical charts were then reviewed to identify associated risk factors. RESULTS: In total 281 corneal scrapings were included, with a positive culture recovery rate of 75%. Bacterial keratitis accounted for 84.8% of culture-positive ulcers, followed by fungi (10%) and finally Acanthamoeba (5.2%); 73% of ulcers were monomicrobial in origin and 28% polymicrobial. We found an increase in Gram-negative micro-organisms over time. General sensitivity to antibiotics did not change over time. A major risk factor for Gram-positive involvement was ocular surface disease, whereas contact lens wear was a major risk factor for Gram-negative involvement. CONCLUSIONS: Bacterial keratitis was found to be the major cause of infectious keratitis in Vancouver, B.C. The majority of bacterial ulcers were caused by Gram-positive bacteria. However, we found an increase in Gram-negative involvement over time. Contact lens wear was identified as the major risk factor for development of Gram-negative ulcers. Pre-existing ocular disease was associated with Gram-positive infection. Susceptibility of Gram-negative bacteria to common broad-spectrum antibiotics was high, but susceptibility of Gram-positive bacteria to these antibiotics was lower and more variable.

Paediatric infectious keratitis at tertiary referral centres in Vancouver, Canada.

OBJECTIVE: To report the clinical and microbiological profiles of paediatric patients with infectious keratitis in Vancouver, Canada. DESIGN: In this observational case series, the microbiology results and medical records of 17 eyes with microbial keratitis in 16 children aged 17 years or younger were retrospectively reviewed. These patients had undergone corneal scraping between May 2006 and April 2011 at BC Children's Hospital or Vancouver General Hospital Eye Care Centre in Vancouver, British Columbia, Canada. Demographic information, clinical features, predisposing factors, results of microbiology studies, antibiotic susceptibilities, treatment course and outcomes were analysed. RESULTS: The mean age of patients was 11±5.7 years (range 1-17 years) and the male:female ratio was 1.4:1. Major predisposing factors were contact lens wear (6/17; 35%), and pre-existing ocular surface conditions including blepharitis (3/17; 18%) and Stevens-Johnson syndrome (3/17; 18%). Four patients had a previous corneal ulcer. The most commonly isolated microorganisms were Staphylococcus epidermidis and Acanthamoeba. Acanthamoeba was isolated in 67% of contact lens-related corneal ulcers, while the remaining 33% of contact lens-related corneal ulcers were associated with infection with Pseudomonas aeruginosa. Final visual acuity was better than 20/60 in 9 out of 16 patients (56%). Three patients subsequently required surgical management with either penetrating keratoplasty or deep anterior lamellar keratoplasty for treatment of corneal scarring. CONCLUSIONS: Contact lens wear and pre-existing ocular surface conditions are significant risk factors for the development of infectious keratitis in our paediatric population. Knowledge of regional patterns of infection and susceptibility are essential in ensuring prompt treatment of this potentially sight-threatening condition.

Very minimal fluence photodynamic therapy for chronic central serous chorioretinopathy.

OBJECTIVE: To describe the safety and efficacy of very minimal fluence photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSC). DESIGN: Retrospective case series. PARTICIPANTS: Five patients with chronic CSC. Two had previously failed alternative therapies, and one was taking concomitant corticosteroids. METHODS: Patients were treated with very minimal fluence PDT (12 J/cm(2), 150 mW/cm(2), for 80 seconds). Median follow-up time after PDT was 100 days (range, 51 to 154). RESULTS: All patients experienced an improvement in visual acuity and symptoms, as well as complete resolution of subretinal fluid. CONCLUSIONS: Very minimal fluence PDT appears to be a safe and effective treatment for chronic CSC. Based on these preliminary findings, a randomized controlled trial is warranted.

Physical and emotional health effects and social consequences after participation in a low-fat, high-carbohydrate dietary trial for more than 5 years.

PURPOSE: Little is known about the potential adverse effects of interventions to reduce dietary fat. We examined the physical and emotional health effects, and social consequences experienced by women at high risk for breast cancer who had participated in a low-fat diet intervention, randomized, controlled trial for at least 5 years. METHODS: Participants in the Canadian Diet and Breast Cancer Prevention Trial from British Columbia were mailed a survey questionnaire that included the validated Medical Outcomes Study 36-item Short Form Health Survey (SF-36) and Women's Health Questionnaire (WHQ), and a series of questions on health-related and social constructs. Responses were compared between the diet intervention and control groups by menopausal status. RESULTS: Completed questionnaires were returned by 359 women in the diet intervention group and 382 in the control group. No significant differences were found between these groups for SF-36 and WHQ health outcomes, hair/nail changes, physical activity levels, family/friend support levels, and doctor visits. Significantly more women in the intervention group reported taking products for arthritis (other than pain medication), greater difficulty in maintaining eating habits in social situations and at work, greater stress, and guilt related to personal eating habits. These findings persisted for both premenopausal and postmenopausal women. CONCLUSION: Changes resulting from a low-fat diet intervention can be incorporated into women's daily lives with limited long-term negative effects.