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K R Wilcox

Publications and source records attributed to K R Wilcox.

13 recordsLinked to original sources

Emergence of vancomycin resistance in Staphylococcus aureus. Glycopeptide-Intermediate Staphylococcus aureus Working Group.

BACKGROUND: Since the emergence of methicillin-resistant Staphylococcus aureus, the glycopeptide vancomycin has been the only uniformly effective treatment for staphylococcal infections. In 1997, two infections due to S. aureus with reduced susceptibility to vancomycin were identified in the United States. METHODS: We investigated the two patients with infections due to S. aureus with intermediate resistance to glycopeptides, as defined by a minimal inhibitory concentration of vancomycin of 8 to 16 microg per milliliter. To assess the carriage and transmission of these strains of S. aureus, we cultured samples from the patients and their contacts and evaluated the isolates. RESULTS: The first patient was a 59-year-old man in Michigan with diabetes mellitus and chronic renal failure. Peritonitis due to S. aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S. aureus peritonitis associated with dialysis. The removal of the peritoneal catheter plus treatment with rifampin and trimethoprim-sulfamethoxazole eradicated the infection. The second patient was a 66-year-old man with diabetes in New Jersey. A bloodstream infection due to S. aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S. aureus bacteremia. This infection was eradicated with vancomycin, gentamicin, and rifampin. Both patients died. The glycopeptide-intermediate S. aureus isolates differed by two bands on pulsed-field gel electrophoresis. On electron microscopy, the isolates from the infected patients had thicker extracellular matrixes than control methicillin-resistant S. aureus isolates. No carriage was documented among 177 contacts of the two patients. CONCLUSIONS: The emergence of S. aureus with intermediate resistance to glycopeptides emphasizes the importance of the prudent use of antibiotics, the laboratory capacity to identify resistant strains, and the use of infection-control precautions to prevent transmission.

Aged↗

Tuberculosis and AIDS.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗

Evaluation of assays for the detection of antibodies to rubella. A report based on data from the College of American Pathologists Surveys of 1982.

Data from laboratories participating in the College of American Pathologists Surveys in 1982 provided information on the trends in testing for antibodies to rubella. Methods used by participants included: passive hemagglutination, 29%; latex agglutination card assay test, 25%; hemagglutination inhibition, 19%; enzyme immunosorbent assays, 13%; indirect fluorescent antibody assays, 11%; and radioimmunoassay, 3%. The results from these methods generally agreed well with the standard HI test, particularly for detection of immunity in negative and strongly positive samples. Laboratories should use caution, however, that the tests they use give satisfactory results with low titered sera. Compared to laboratories using the one to three-day-old chick cells with Heparin-MnCl2 for HI, laboratories using Human O Cells tended to get higher titers, and laboratories using Fixed Chick cell or Kaolin methods tended to get lower titers.

Animals↗

Cohort study of Michigan residents exposed to polybrominated biphenyls: epidemiologic and immunologic findings.

Polybrominated biphenyls (PBB) were dispersed widely in Michigan by a 1973 shipping accident in which PBB was introduced into cattle feed. Human exposure resulted principally from ingestion of contaminated dairy food products. To determine whether PBB exposure has or will cause acute or chronic illness, a prospective cohort study of 4545 persons has been undertaken. Three exposure groups were sought; all persons living on PBB-quarantined farms; persons who had received food directly from such farms; workers (and their families) engaged in PBB manufacture. Enrollment rates were 95.6, 95.1 and 78.0%. Also enrolled were 725 persons with low-level PBB exposure. All were queried concerning 17 symptoms and conditions related possibly to PBB. Venous blood was drawn on 3639 and analyzed for PBB by gas chromatography. Mean serum PBB levels were 26.9 ppb in quarantined farm families, 17.1 in recipients, 43.0 ppb in workers, and 3.4 ppb in the low exposure groups. No associations were found between serum PBB levels and symptom prevalence rates. To evaluate peripheral lymphocyte function, T and B cell quantitation and in vitro responses to 3 nonspecific mitogens were studied in 34 persons with highest PBB levels (mean, 787 ppb), and in 56 with low values (mean, 2.8 ppb). No statistically significant differences in lymphocyte number or function were noted.

Adolescent↗

Impact of swine influenza vaccine on serum antibody.

Comparison of a 1976 serum survey with one of 1977 has permitted an assessment of the impact of the national swine influenza vaccine program of 1976-1977 on the antibody status of the Michigan population. Prevalence of HI influenza virus antibody in premarital sera collected in 1976 prior to the vaccine program was compared to that in similar sera collected in 1977. Overall prevalence of A/New Jersey antibody (titers greater than or equal to 1:10) in 1976 sera was 22.3%. Little antibody was detected in sera from persons less than 40 years of age and prevalence peaked at age 50. Increased antibody prevalence was found for all age groups in sera collected in 1977 following the vaccine program, and the overall prevalence was 41.6%. Only 3.5% of those under 19 years of age were vaccinated, and post-vaccine prevalence for this group was 10%. This age group, comprising about 30% of the state population, appears to have had least exposure to swine influenza virus, and may be the population segment at greatest risk of infection should strains of this antigenic composition reappear. In contrast, highest prevalence of A/Victoria antibody was found in the 15 to 19 age group, where prevalence was 52%, compared to an overall prevalence at 40%.

Adolescent↗