Clerkship timing and disparity in performance of racial-ethnic minorities in the medicine clerkship.

PURPOSE: To determine the effect of the timing of the medicine clerkship on academic performance in different racial-ethnic student groups. METHOD: Performance was measured by the average assessment of clinical preceptors, an OSCE (objective structured clinical examination), and the NBME (National Board of Medical Examiners) medicine subject examination. Outcomes were analyzed by student racial-ethnicity and clerkship sequence. RESULTS: Of the 650 students who took the clerkship over four years, 6.9% were African American, 34.6% were Asian-Pacific Islander, 9.1% were Hispanic and 49.4% were white. African American and Hispanic students were in the earliest clerkship sequence 46.7% and 30.5% of the time, respectively, compared to 20% of Asian-Pacific Islanders and 27.4% of white students. Academic performance improved with time and varied among the racial-ethnic groups. All groups achieved higher scores in the NBME medicine examination later in the year but scores of African American and Hispanic students increased to a greater degree than other students. CONCLUSION: Sometimes, a "few points" on the NBME medicine examination can affect students' final grades and alter their attractiveness to competitive residency training programs. All students, but African American and Hispanic students, in particular, can significantly improve their scores in the NBME medicine examination by taking the clerkship later in the year. Students should be counseled regarding the timing effect and methods to neutralize the disparity should be considered.

Antibiotics in the treatment of acute exacerbations of chronic bronchitis.

The benefit of antimicrobial therapy for patients with an acute exacerbation of chronic bronchitis (AECB) remains controversial for two main reasons. First, the distal airways of patients with chronic bronchitis are persistently colonised, even during clinically stable periods, with the same bacteria that have been associated with AECB. Second, bacterial infection is only one of several causes of AECB. These factors have led to conflicting analyses on the role of bacterial agents and the response to antimicrobial therapy of patients with AECB. An episode of AECB is said to be present when a patient with chronic obstructive pulmonary disease (COPD) experiences some combination of increased dyspnoea, increased sputum volume, increased sputum purulence and worsening lung function. While the average COPD patient experiences 2 - 4 episodes of AECB per year, some patients, particularly those with more severe airway obstruction, are more susceptible to these attacks than others. Bacterial agents appear to be particularly associated with AECB in patients with low lung function and those with frequent episodes accompanied by purulent sputum. Non-typeable Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis account for up to 50% of episodes of AECB. Gram-negative bacilli are more likely to occur in patients with more severe lung disease. Antibiotics have been used to ameliorate AECB, to prevent AECB and to prevent the long-term loss of lung function that characterises COPD. Numerous prevention trials have been conducted with fairly consistent results; antibiotics do not lessen the number of episodes of AECB but do reduce the number of days lost from work. Most antibiotic trials have studied the impact of treatment on episodes of AECB and results have been inconsistent, largely due to patient selection and end point definition. In patients with severe airway obstruction, especially in the presence of purulent sputum, antibiotic therapy significantly shortens the duration of symptoms and can be cost-effective. Over the past 50 years, virtually all classes of antimicrobial agents have been studied in AECB. Important considerations include penetration into respiratory secretions, spectrum of activity and antimicrobial resistance. These factors limit the usefulness of drugs such as amoxicillin, erythromycin and trimethoprim-sulfamethoxazole. Extended-spectrum oral cephalosporins, newer macrolides and doxycycline have demonstrated efficacy in clinical trials. Amoxicillin-clavulanate and flouoroquinolones should generally be reserved for patients with more severe disease. A number of investigational agents, including ketolides and newer quinolones, hold promise for treatment of AECB.

Vancomycin-resistant Enterococcus faecium in a Veterans Affairs Medical Center: association with antibiotic usage.

BACKGROUND: Colonization and infection with vancomycin-resistant Enterococcus faecium (VREF) has been associated with the use of vancomycin and other antibiotics in individual patients. The objective of this study was to determine the association of VREF with the aggregate usage of antibiotics on nursing units in a hospital. METHODS: This was a retrospective correlation study. A usage ratio was calculated for each parenteral antibiotic on each nursing unit as the per-bed usage by weight of that antibiotic divided by its average usage throughout the hospital. An average usage ratio (AUR) for each nursing unit was calculated as the mean of usage ratios of individual antibiotics. The AUR was used to compare the usage of antibiotics among nursing units in the hospital. The incidence of VREF infections on individual nursing units in a Veterans Affairs Medical Center was correlated with the usage of parenteral antibiotics separately and in aggregate in univariate and multivariate regression analyses. RESULTS: The AUR was strongly and positively correlated with the recovery of VREF on individual nursing units. By univariate analyses, increasing use of each antibiotic tested was associated with isolation of VREF but only clindamycin remained significant in the multivariate model. However, usage of various antibiotics was highly interrelated, and only clindamycin usage was significantly correlated with usage of all other antibiotics studied. Intensive care and acute care units and units with fewer patient beds were more likely to have patients with VREF infection than were subacute care units (p < 0.003) or larger units (p < 0.01). CONCLUSIONS: VREF infections were associated with greater aggregate antibiotic use on nursing units. Determination of antibiotic usage ratios may provide a convenient and useful tool for examining the association of antibiotic usage with other nosocomial infections.

Treatment of vancomycin-resistant Enterococcus faecium infections with an investigational streptogramin antibiotic (quinupristin/dalfopristin): a report of fifteen cases.

New therapies for vancomycin-resistant Enterococcus faecium (VREF) infections are urgently needed. We describe the treatment of 15 patients with VREF infection with quinupristin/dalfopristin (RP 59500), a new injectable streptogramin antibiotic. Primary infections treated were bacteremia (4), urinary tract (4), intraabdominal (5), otitis externa (1), and meningitis (1). Minimum inhibitory concentrations for quinupristin/dalfopristin ranged from 0.5 microgram/ml or less to 2 micrograms/ml, and minimum bactericidal concentrations were greater than 64 micrograms/ml for all VREF isolates tested. Peak serum inhibitory titers following infusion of quinupristin/dalfopristin ranged from 1:8 to 1:64; all bactericidal titers were less than 1:2. Development of resistance to quinupristin/dalfopristin during therapy was not observed. The only drug-related adverse effect noted was phlebitis in 4 patients; all had received quinupristin/dalfopristin by peripheral venous infusion. Three patients had clinical and bacteriologic cures. Relapses occurred in 5 patients with recovery of VREF from infected sites in post-treatment cultures. Ten patients died of severe underlying disease; VREF was believed to contribute directly to the death of only 1 patient. While evaluation of clinical efficacy was complicated by the severity of underlying disease in patients with VREF infection, our experience suggests that quinupristin/dalfopristin is a safe and potentially useful agent for the treatment of VREF infections.

Pneumonia complicating adult respiratory distress syndrome.

Aspiration bronchopneumonia occurs in most patients undergoing prolonged mechanical ventilation. These pneumonias adversely affect lung function and release bacteria into the systemic circulation via the lungs' lymphatics. Through this mechanism, clinically occult pneumonias may initiate activation of systemic inflammation, leading to the syndrome of multiple organ failure.

Colonization in patients receiving and not receiving topical antimicrobial prophylaxis.

The influence of topical antimicrobial prophylaxis (TAP) on colonization of oropharynx and trachea was studied in patients receiving and not receiving prophylaxis. Twenty-two patients in Intensive Care Unit (ICU) I (Group 1) received TAP (tobramycin, colistin, and amphotericine B in oropharynx and stomach). Simultaneous to Group 1, 21 patients (Group 2) not receiving TAP were studied in ICU I. A control group of patients admitted to another, identical, ICU (ICU II), where no TAP was administered, were studied simultaneously (Group 3a, n = 23). A second control group (Group 3b, n = 31), was formed by collecting data from patients admitted to ICU I in Period II. Patients receiving TAP were less frequently colonized than patients not receiving prophylaxis. Moreover, of the patients not receiving TAP, those staying in the ICU where TAP was administered (Group 2) were less frequently colonized than patients in another ICU (Group 3). Of the patients not colonized on admission, those staying in the ICU where TAP was administered remained free of colonization for a longer time. In the ICU where no TAP was administered, more patients were colonized simultaneously and cross-acquisition occurred more frequently. TAP significantly influenced colonization of oropharynx and trachea in patients receiving and not receiving prophylaxis within the same ICU as compared with patients not receiving prophylaxis in another identical ICU.

Human health effects associated with hazardous waste sites.

Many hazardous waste sites contain chemicals that cause serious disease in humans. However, adverse effects are uncommon. Evidence for harm comes principally from epidemiologic studies in which proof of exposure usually is lacking.

Elastase activity in bronchoalveolar lavage fluid from oxygen-exposed, Pseudomonas-infected baboons.

The adult respiratory distress syndrome is a major cause of morbidity and mortality in critical care patients. Lung injury in this syndrome is frequently associated with lung infection. The combined insults result in an influx of neutrophils and damage to the pulmonary epithelium. We investigated whether active neutrophil elastolytic activity was present in the bronchoalveolar fluid in baboons with mild or moderate hyperoxic lung injury and infection. Group A (N = 7) was exposed for 6 days to FIO2 = 0.8 and then inoculated by intratracheal bolus with Pseudomonas aeruginosa strain DGI-R130 (PA); the FIO2 was reduced to 0.5. Group B (N = 6) was exposed to similar concentrations of inspired oxygen but inoculated with buffered saline. Antibiotics included parenteral penicillin and topical gentamicin and polymyxin B. All 3 were given continuously in group B but stopped 24 h prior to PA inoculation in group A. Bronchoalveolar lavage fluid was collected 1 week before oxygen administration, when the FIO2 was reduced (day 6 or 7) and prior to necropsy (day 11). Hemodynamic, pulmonary function, microbiological, and biochemical variables were studied. Injured, infected animals (group A) had significant elevations of mean pulmonary artery pressure and decreases in total lung capacity and PaO2 compared both to baseline and to group B at day 11. At autopsy, group A had significant increases of bronchoalveolar lavage fluid (BALF) neutrophils and bacterial pathogens. Elastase levels in BALF (equal to 0 at baseline) rose to 136 +/- 98 ng/ml in group A vs. 6 +/- 14 ng/ml in group B. The elastase was inhibited by inhibitors of serine proteases including ones specific for neutrophil elastase. On Sephacryl S-300 chromatography the elastase activity eluted near human alpha 2-macroglobulin and separated from other proteolytic activity. These studies demonstrate a significant level of elastase in BALF from injured, infected baboons compared to injured, uninfected animals.