Increased prevalence of community-acquired methicillin-resistant Staphylococcus aureus in hand infections at an urban medical center.

BACKGROUND: The purpose of this article is to report the increased incidence of community-acquired methicillin-resistant S. aureus in hand infections at an urban medical center. METHODS: The authors performed a retrospective review of all patients with hand infections over a 21-month period, and all patients with culture-positive methicillin-resistant S. aureus were identified. Cases determined to be nosocomial were excluded. The study period was divided into three 7-month periods. RESULTS: A total of 343 hand infections were treated over a 21-month period. Eighty-nine patients (26 percent) with culture positive methicillin-resistant S. aureus were identified; of these, 75 were determined to be community-acquired methicillin-resistant S. aureus patients. Statistical analysis was performed using the Fisher's exact test (p < 0.0001), the chi-square test for equal proportions, the Cochran-Armitage trend test, and two-way analysis of variance. The demographics of the patients were compared using two-way analysis of variance, and patients were found to be similar in all three time periods with respect to mean age and sex. The incidence of community-acquired methicillin-resistant S. aureus increased to 40 percent during the last 7-month period compared with 14 percent during the first two periods. Overall, the incidence of methicillin-resistant S. aureus increased to 47 percent during the last 7 months compared with 16 percent and 17 percent in the first two 7-month periods, respectively. Based on their treatment approach and literature review, the authors have developed an algorithm to treat community-acquired methicillin-resistant S. aureus hand infections. CONCLUSIONS: The authors' findings at Temple University Hospital may help to alert health care providers to take necessary steps to control the spread of methicillin-resistant S. aureus in the community and in the inpatient setting. Cultures should be carefully followed and infections should be treated with appropriate antibiotics.

Hyperoxia and angiogenesis.

We hypothesized that tissue hyperoxia would enhance and hypoxia inhibit neovascularization in a wound model. Therefore, we used female Swiss-Webster mice to examine the influence of differential oxygen treatment on angiogenesis. One milliliter plugs of Matrigel, a mixture of matrix proteins that supports but does not itself elicit angiogenesis, were injected subcutaneously into the mice. Matrigel was used without additive or with added vascular endothelial growth factor (VEGF) or anti-VEGF antibody. Animals were maintained in hypoxic, normoxic, or one of four hyperoxic environments: hypoxia -- 13 percent oxygen at 1 atmosphere absolute (ATA); normoxia -- 21 percent oxygen at 1 ATA; hyperoxia -- (groups a-d) 100 percent oxygen for 90 minutes twice daily at the following pressures: Group a, 1 ATA; Group b, 2 ATA; Group c, 2.5 ATA; Group d, 3.0 ATA. Subcutaneous oxygen tension was measured in all groups. The Matrigel was removed 7 days after implantation. Sections were graded microscopically for the extent of neovascularization. Angiogenesis was significantly greater in all hyperoxic groups and significantly less in the hypoxic group compared with room air-exposed controls. Anti-VEGF antibody abrogated the angiogenic effect of both VEGF and increased oxygen tension. We conclude that angiogenesis is proportional to ambient pO(2) over a wide range. This confirms the clinical impression that angiogenesis requires oxygen. Intermittent oxygen exposure can satisfy the need for oxygen in ischemic tissue.

Reliability and accuracy of techniques for surface area measurements of wounds and scars.

The applicability of simple methods to measure the size of pathological skin lesions for management and research has been poorly studied to date. The interobserver reliability and accuracy (validity) was established for planimetry by photography and planimetry by tracing on a transparent sheet in this study. Drawings of 25, 50, and 75 cm(2) were created on 3 locations with increasing curvature (back, thigh, and forearm) in 20 healthy volunteers. Three investigators evaluated the drawings by both planimetry techniques. Both techniques showed a good reliability (r >or= 0.82, intraclass correlation) for 25 cm(2) areas. Planimetry by photography was more reliable than planimetry by tracings for the 50 -and 75-cm(2) areas and was more accurate than planimetry by tracing for all areas except for the area with the greatest curvature, the forearm. The study permits the conclusion that planimetry by photography is more suitable for surface area measurements than planimetry by tracing except for extremely curved body parts, where it is likely that effects of distortion supervene.

Scar assessment tools: implications for current research.

Scarring is considered a major medical problem that leads to cosmetic and functional sequelae. Scar tissue is clinically distinguished from normal skin by an aberrant color, rough surface texture, increased thickness (hypertrophy), occurrence of contraction, and firmness. Marked histologic differences are the change in dermal architecture and the presence of cells such as the myofibroblast. Many assessment tools are available for analysis of pathologic conditions of the skin; however, there is no general agreement as to the most appropriate tools for evaluation of scar tissue. This review critically discusses currently available objective measurement tools, subjective assessment tools, and potential devices that may be available in the future for scar assessment.