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  • A prospective, longitudinal study of the behavior of serologically classified isolates of Escherichia coli in women with recurrent urinary tract infections JOURNAL OF INFECTION Vosti, K. L. 2007; 55 (1): 8-18


    This study characterizes further the behavior of serologically classified isolates of Escherichia coli in women with recurrent urinary tract infections (UTIs).A prospective, longitudinal study of 203 young to middle-aged women with UTIs was conducted. Seven hundred and sixty-one UTIs due to E. coli were identified in the 203 women during observation periods of 1.1-19.4 years. Isolates from urine were routinely serologically classified. Clusters of UTIs and rates per year of infections with the same serogroup were defined to quantify further UTIs.One hundred and forty-eight (73%) of the 203 women experienced 2-42 UTIs with E. coli. Fifteen percent of recurrences occurred within 1 month of the previous infection; 57%, 6 months; and 70%, 1 year. During the first four months, recurrences with the same serogroup accounted for 81-50% of recurrences; thereafter, recurrences with a different serogroup were more frequent. Clusters of UTIs occurred in 52% of the 148 women and ranged in size from 2-5 infections. Multiple recurrences with the same serogroup were more frequently caused by a few common serogroups.Isolates of a few common serogroups of E. coli were associated with the great majority of both index and recurrent UTIs. Some isolates of both common and less common serogroups were associated with multiple recurrences with the same serogroup. The wide range in rates/year among recurrences with isolates of different serogroups in individual women were consistent with the hypothesis that these differences were more likely to be due to differences in virulence of the isolates than to host factors.

    View details for DOI 10.1016/j.jinf.2007.01.006

    View details for Web of Science ID 000247905400002

    View details for PubMedID 17331583

  • Infections of the urinary tract in women - A prospective, longitudinal study of 235 women observed for 1-19 years MEDICINE Vosti, K. L. 2002; 81 (5): 369-387


    A prospective long-term study was conducted of 235 young to middle-aged women with past histories of and/or active infections of the urinary tract. The present report defines certain characteristics of the population and of the 1,018 confirmed infections of the urinary tract that occurred during observation periods ranging from 1.1 to 19.4 years (mean, 7.4 yr). The population could be divided into 3 groups: women with confirmed infections who did (Group 1, n = 19) or did not (Group 2, n = 191) receive courses of antimicrobial prophylaxis and those who did not have confirmed infections (Group 3, n = 25). The 3 groups differed significantly only in their mean infection rates per year (3.1, 0.8, and 0.0, respectively). The number of infections among individual women ranged from 0 to 42. The patterns of recurrent infections among individual women ranged widely and were not predictable. Clusters of infections occurred in 45.7% of the women and ranged in size from 2 to 12 infections per cluster. The proportions of different infecting organisms and clinical syndromes were similar to those reported by others. accounted for the great majority of infections. Eighty-five percent of the isolates of tested were serologically classified. A total of 50 different O groups were identified. Three (O4, O6, and O75) of the 131 potential O groups accounted for 49% of the isolates that could be classified. In each of the 4 clinical syndromes, these same 3 O groups were also the most frequently identified. The ability to classify serologically the infecting isolates of permitted a more complete definition of the complexity of patterns of recurrent infections among individual women. The findings in the present study are compared with those in the literature.

    View details for DOI 10.1097/

    View details for Web of Science ID 000178131200003

    View details for PubMedID 12352632

  • Brain abscess due to Listeria monocytogenes - Five cases and a review of the literature Eckburg, P. B., Montoya, J. G., Vosti, K. L. LIPPINCOTT WILLIAMS & WILKINS. 2001: 223-235

    View details for Web of Science ID 000170114800001

    View details for PubMedID 11470983

  • Outcome measurement in postgraduate year one of graduates from a medical school with a pass fail grading system ACADEMIC MEDICINE Vosti, K. L., Jacobs, C. D. 1999; 74 (5): 547-549


    To measure the performances of first-year residents who had graduated from a medical school with a pass/fail grading system and to compare the preparedness of these graduates with that of their peers.All 169 graduates of Stanford University School of Medicine's classes of 1993 and 1994 were included in this study. First-year program directors rated the performance of each Stanford graduate in 11 areas, compared the graduate's clinical preparedness with that of his or her peer group, and rated the accuracy of the dean's letter in presenting the graduate's capabilities.Responses were obtained for 144 of the 169 graduates (85%). The program directors rated the overall clinical competencies of most of the graduates as "superior" (76%) or "good" (22%); they rated very few as "unsatisfactory" (2%). When the Stanford graduates were compared with their peers, their clinical preparedness was judged "outstanding" (33%), "excellent" (44%), and "good" (20%); very few were judged "poor" (3%). Stratification of programs by either hospital or medical specialty did not reveal significant differences in overall clinical competence. Ninety-one percent of the responses reported that the dean's letters had accurately presented the capabilities of the graduates.Graduates from a medical school with a two-interval, pass/fail system successfully matched with strong, highly-sought-after postgraduate training programs, performed in a satisfactory to superior manner, and compared favorably with their peer group.

    View details for Web of Science ID 000080442700027

    View details for PubMedID 10353289

  • The relationship of clinical knowledge to months of clinical training among medical students ACADEMIC MEDICINE Vosti, K. L., Bloch, D. A., Jacobs, C. D. 1997; 72 (4): 305-307


    To assess the correlation of the number of months of clinical training with clinical knowledge, as measured by the United States Medical Licensing Examination (USMLE) Step 2.The total number of months of clinical training and percentile scores on USMLE Step 2 were determined for 217 Stanford. University School of Medicine graduates from 1992 through 1994. Percentile scores on each subsection of the Medical College Admission Test (MCAT) and the National Board of Medical Examiners Part 1 or USMLE Step 1 (Part 1/Step 1) for the graduates were also determined. For some analyses the graduates were separated into three groups according to the duration of clinical training. The Pearson product-moment correlation coefficient was used to quantify and define the significance of correlations. The Jorickheere-Terpstra nonparametric test was used to assess trends across the three groups. A multiple linear regression model was used to test the effects of confounding variables.The total numbers of clerkship months ranged from 12 to 23; the median was 18. A highly significant correlation was found between increasing months of clinical training and increasing scores on Step 2 (p = .002); a weaker significant correlation was found with scores on Part 1/Step 1 (p = .03). The correlation for Step 2 scores did not diminish appreciably (p = .004) when scores for Part 1/Step 1 and each MCAT subsection were introduced into the regression model.A highly significant correlation was found between the amount of clinical training and the acquisition and utilization of clinical knowledge. In the current climate of concerns about the rising costs of medical education, the impulse to solve these concerns by decreasing the amount of medical students' clinical training should be approached with caution.

    View details for Web of Science ID A1997WV34100023

    View details for PubMedID 9125948



    The importance of group B streptococcus (GBS) as a cause of serious infectious disease among adults is not widely appreciated. In adults, the modes of acquisition and transmission are unknown. Since most hospital-based studies of GBS bacteremia in adults consist of small numbers of patients, the clinical spectrum of disease is not well described. Our retrospective study reviews the clinical features, antimicrobial therapy, and risk factors for mortality of 32 adult patients (18 women and 14 men) with GBS bacteremia and compares the proportion of isolates from the different beta-hemolytic streptococci sero-groups. We found that 39% of isolates from adult blood cultures were group B, a frequency nearly identical to that of group A streptococcal bacteremia. Most (66%) adult patients were more than 50 years old. Primary bacteremia was the most frequent clinical diagnosis, occurring in 7 (22%) of 32 patients. Nonhematologic cancer was the most frequently associated condition (25%). Nineteen percent of the patients had diabetes mellitus. The overall mortality rate was 31% and was significantly associated with increasing age. Our results are compared to those obtained by a review of all 5 previous comparable studies and demonstrate that GBS bacteremia is a serious infection in adults with increased mortality related to advancing age.

    View details for Web of Science ID A1995RM12600002

    View details for PubMedID 7623653

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