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Dirk M Elston

Publications and source records attributed to Dirk M Elston.

At least 19 recordsLinked to original sources
PubMed2007

Community-acquired methicillin-resistant Staphylococcus aureus.

UNLABELLED: Published data confirm that community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections are increasing in incidence in both urban and rural settings. The statistical risk is higher for athletes, military personnel, prison inmates, intravenous drug abusers, the homeless, children in daycare, and certain Native American groups, but the infections are by no means restricted to these populations. Roughly 85% of the infections involve the skin and subcutaneous tissue, with the most common presentations being an abscess or folliculitis. The typical associated gene cassette is quite small and codes only for methicillin resistance. Abscesses generally respond to drainage. LEARNING OBJECTIVE: At the conclusion of this learning activity, participants should recognize groups at high risk for community-acquired MSRA infections and manage these infections appropriately.

Adolescent↗
PubMed2006

Smooth muscle pattern is more reliable than the presence or absence of an internal elastic lamina in distinguishing an artery from a vein.

BACKGROUND: Major pathology textbooks suggest that the shape of the vessel and the presence or absence of an internal elastic lamina are the best means to distinguish an artery from a vein. Because the shape of the vessel is highly dependent upon the plane of section, the internal elastic lamina is often cited as a more reliable criterion. After evaluating a patient with superficial thrombophlebitis, in whom these conventional criteria had led to a misdiagnosis of polyarteritis nodosa, we sought to determine whether the pattern of smooth muscle in the media is a more sensitive discriminator between an artery and a vein. METHODS: Anatomically identified arteries and veins were harvested from extremity amputation specimens and stored autopsy organ specimens and reviewed by two dermatopathologists who were blinded to the gross pathologist's impression. The biopsies were assessed for the smooth muscle pattern and the presence or absence of an internal elastic lamina. RESULTS: Forty-seven of the 50 cases (94%) were concordant with the pathologist's gross impression using only the smooth muscle pattern to differentiate an artery from a vein. On the basis of the presence or absence of an internal elastic lamina, 41 of 50 cases (82%) were concordant with the prosector's designation of the vessel. LIMITATIONS: Vessels were harvested from a variety of sites, with lower extremity vessels predominating. There may be some regional variability not addressed in this study. CONCLUSION: In this study, the pattern of muscle fibers within the vascular media discriminated between arteries and veins better than assessment of the presence or absence of an internal elastic lamina. Although no single criterion is 100% reliable, assessment of both these criteria may minimize the risk of misinterpreting vessels in the deep dermis and subcutis.

Arteries↗
PubMed2006

Allergic contact dermatitis caused by white petrolatum on damaged skin.

Petrolatum rarely causes hypersensitivity reactions. We report a case of a 51-year-old white man with allergic contact dermatitis due to white petrolatum on damaged skin. The patient, who presented with a history of hand dermatitis and intolerance to ointments for years, was patch-tested with white petrolatum on scratched skin. Patch tests with the European Standard series, preservatives, steroids, vehicles, and emulsifiers were also performed. The patch-test reaction to white petrolatum on scratched skin was positive at 48 and 96 hours. All other patch-test results were negative.

Dermatitis, Allergic Contact↗
PubMed2005

Comparison of colchicine, dapsone, triamcinolone, and diphenhydramine therapy for the treatment of brown recluse spider envenomation: a double-blind, controlled study in a rabbit model.

OBJECTIVE: To compare the efficacy of dapsone, diphenhydramine, colchicine, and intralesional triamcinolone in the treatment of brown spider bites. We used a purified venom that reproducibly produces a large eschar. To mimic real-life circumstances, all agents were administered following a 2-hour delay after envenomation. The animals were evaluated for the presence of coagulopathy to determine if the incidence of systemic findings correlated with the type of treatment. DESIGN AND SETTING: In a research laboratory, 60 New Zealand white rabbits each received an intradermal injection of 20 microg of purified Loxosceles reclusa venom. The rabbits were divided into 5 groups of 12; a control group and 4 groups treated with a drug (either colchicine, triamcinolone, diphenhydramine, or dapsone). Measured end points included maximum eschar size as well as histologic grading of depth, inflammation, and thrombosis. INTERVENTIONS: Treatment with colchicine, triamcinolone, diphenhydramine, or dapsone. MAIN OUTCOME MEASURES: Maximum eschar size as well as histologic grading of depth, inflammation, and thrombosis. RESULTS: There was no significant difference with respect to eschar size (1-way analysis of variance, P = .003). There was no significant difference between any treatment with respect to presence or absence of ulcer, necrosis, large vessel vasculitis, or small vessel vasculitis. The only outcome of significance was that triamcinolone offered protection from thrombosis (chi2 likelihood ratio, P = .04). We also noted evidence of coagulopathy in all of the envenomated animals. The rabbits had grossly elevated activated partial thromboplastin time results, which were corrected with 1:1 mixing with normal rabbit plasma, suggesting an acquired factor deficiency. We did not detect an individual factor deficiency or a lupus anticoagulant. CONCLUSIONS: In a rabbit model, none of the agents tested (dapsone, diphenhydramine, colchicine, and intralesional triamcinolone) had an effect on eschar size. Triamcinolone appeared to offer some protection against histologic evidence of thrombosis, but this protection did not translate into a difference in clinical outcome. All animals developed evidence of coagulopathy, regardless of treatment. The coagulopathy could be corrected by fresh rabbit plasma, suggesting an acquired factor deficiency.

Animals↗