MRSA Infections: A Ten-year Retrospective

Staff
5/3/2012

Taiwanese researchers have concluded that community-associated methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen of ocular infections; in countries with a high prevalence of MRSA, ophthalmologists should be aware of such epidemiologic information.

Data collected from 519 patients with culture-proven S. aureus ocular infections in a 10-year period at Chang Gung Memorial Hospital was analyzed for patient demographics, clinical features and antibiotic susceptibility of ocular infections caused by community-associated and health-care-associated isolates. Two hundred and seventy-one patients with MRSA ocular infections were identified, which comprised 181 CA-MRSA and 93 HA-MRSA isolates. The average rate of MRSA in S. aureus ocular infections was 52.8 percent with a stable trend, whereas the annual ratio of CA-MRSA in ocular MRSA infections averaged 66.1 percent, tending to increase over the 10-year interval. Patients with ocular CA-MRSA were younger. Both CA-MRSA and HA-MRSA isolates were resistant to clindamycin and erythromycin, but CA-MRSA was more susceptible to sulfamethoxazole/trikmethoprim.

Hsiao C, Chuang C, Tan H, Ma D, et al.


Ultra-Wide-Field FA Reveals Pathology Better Than Standard
Compared with conventional imaging, ultra-wide-field fluorescein angiography reveals significantly more retinal vascular pathology in patients with diabetic retinopathy, says a group from the Weill Cornell Medical Center, New York City. They believe improved retinal visualization may alter the classification of diabetic retinopathy and may therefore influence follow-up and treatment of these patients.

The study evaluated patients with diabetic retinopathy using ultra-wide-field FA to compare the visualized retinal pathology with that seen on an overlay of conventional seven standard field (7SF) imaging.

Included were 218 eyes of 118 diabetic patients who underwent diagnostic fluorescein angiography using the Optos Optomap Panoramic 200A imaging system. The visualized area of the retina, retinal nonperfusion, retinal neovascularization and panretinal photocoagulation were quantified by two independent masked graders. The respective areas identified on the ultra-wide-field fluorescein angiography image were compared with an overlay of a modified 7SF image as outlined in the ETDRS.

Ultra-wide-field FA imaging, on average, demonstrated 3.2 times more total retinal surface area than 7SF. When compared with 7SF, ultra-wide-field FA showed 3.9 times more nonperfusion (p<0.001), 1.9 times more neovascularization (p=0.036), and 3.8 times more panretinal photocoagulation (p<0.001). In 22 eyes (10 percent), ultra-wide-field fluorescein angiography demonstrated retinal pathology (including nonperfusion and neovascularization) not evident in a 7SF overlay.

Wessel MM, Aaker GD, Parlitsis G, Cho M, D ľamico DJ, Kiss S.


Laser Versus Glaucoma Drugs: Which Is More Cost-Effective?
A study at the University of Michigan, Ann Arbor, aimed to determine the most cost-effective treatment option for glaucoma. Using a Markov model with a 25-year horizon, they compared the incremental cost-effectiveness of treating newly diagnosed, mild open-angle glaucoma with generic topical prostaglandin analogs, laser trabeculoplasty or observation only.

The incremental cost-effectiveness of laser over no treatment is $16,824 per quality-adjusted life year, the group says. By comparison, the incremental cost-effectiveness of PGAs over no treatment is $14,179 per quality-adjusted life year, and they provide greater health-related quality of life relative to laser. If PGAs are 25-percent less effective owing to poor patient adherence, laser can confer greater value.

Stein J, Kim D, Peck W, Giannetti S, Hutton D.