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T Marrie

Publications and source records attributed to T Marrie.

At least 19 recordsLinked to original sources

The pneumonia severity index predicts time to clinical stability in patients with community-acquired pneumonia.

SETTING: A total of 33 hospitals in 13 countries in North America, Europe, Africa, Asia and Latin America. OBJECTIVE: To investigate the relationship between the pneumonia severity index (PSI) and the time to clinical stability from intravenous to oral antibiotic therapy in hospitalized adult patients with community-acquired pneumonia (CAP). DESIGN: An international, retrospective, observational study of random adult patients meeting the definition of CAP between June 2001 and May 2004. RESULTS: The risk class (RC) according to the PSI was calculated for all patients. The criteria to define when a patient is clinically stable were evaluated daily during the first 7 days of hospitalization in all patients. The mean time to clinical stability for 254 patients in RC I was 4.2 days, for 233 patients in RC II it was 3.9 days, for 395 patients in RC III it was 4.6 days, for 644 patients in RC IV it was 5.0 days and for 296 patients in RC V it was 6.0 days. Significant positive correlations were observed between RC and time to clinical stability (P < 0.0001). CONCLUSION: The PSI is a tool that can be used to predict time to clinical stability (i.e., time to antimicrobial switch therapy) in hospitalized patients with CAP.

Anti-Bacterial Agents↗

HIV infection does not influence clinical outcomes in hospitalized patients with bacterial community-acquired pneumonia: results from the CAPO international cohort study.

In a case-control study, outcomes for 58 human immunodeficiency virus (HIV)-positive patients with community-acquired pneumonia (CAP) were compared with outcomes for 174 HIV-negative patients with CAP. No differences were found in the time to clinical stability, the length of hospitalization, and mortality. Clinical outcomes for hospitalized patients with CAP may not be influenced by HIV infection.

Adult↗

Appropriate antibiotic utilization in seniors prior to hospitalization for community-acquired pneumonia is associated with decreased in-hospital mortality.

BACKGROUND: We analysed the association of mortality and prescription of antibiotics prior to hospitalization for community-acquired pneumonia. METHODS: We used administrative data (hospital abstracts, physician claims, prescriptions) for seniors (age 61 years and over) for Alberta, Canada from 1 April 1994 to 31 March 1999. RESULTS: Hospitalization of 21 191 seniors occurred during the study period. In about 43% of hospitalizations (n = 9034), a physician was consulted prior to hospital admission. Antibiotics were dispensed to 31% of those with a prior physician visit and in about 72%, the antibiotic choice was deemed appropriate. The odds for mortality were significantly decreased in those with prior physician visits (OR = 0.87, P < 0.01), with any antibiotic prescription (OR = 0.66, P < 0.0001), and with an appropriate antibiotic (OR = 0.68, P = 0.03). The choice of an appropriate antibiotic as opposed to an inappropriate antibiotic resulted in a 2.6% absolute and 38% relative mortality reduction. CONCLUSION: Choosing an appropriate outpatient antibiotic in accordance with published expert opinion guidelines compared with inappropriate antibiotic prescriptions decreased hospital mortality in patients subsequently hospitalized for community-acquired pneumonia.

Aged↗

A randomized controlled trial of filgrastim as an adjunct to antibiotics for treatment of hospitalized patients with community-acquired pneumonia. CAP Study Group.

Because of the critical role of neutrophils in host defenses, it was hypothesized that stimulation of neutrophil production and function with Filgrastim would improve the outcome of hospitalized patients with community-acquired pneumonia. To test this hypothesis, a randomized, placebo-controlled, multicenter trial of Filgrastim (300 micrograms/day up to 10 days) as an adjunct to antibiotics was conducted for these patients. Outcome measures included time to resolution of morbidity (TRM, a composite measure of temperature, respiratory rate, blood oxygenation, and chest radiograph), 28-day mortality, length of stay, and adverse events. Filgrastim increased blood neutrophils 3-fold, but TRM, mortality, and length of hospitalization were not affected. Treatment, however, accelerated radiologic improvement and appeared to reduce serious complications (e.g., empyema, adult respiratory distress syndrome, and disseminated intravascular coagulation). Filgrastim administration was safe and well tolerated in these patients. Additional trials are needed to establish the value of this approach to treatment of infectious diseases.

APACHE↗

Bacteremia in nursing home patients. Prevalence among patients presenting to an emergency department.

OBJECTIVE: To measure the prevalence of bacteremia and any correlation between signs and symptoms, risk factors, and laboratory data in elderly patients. DESIGN: Prospective analysis. All patients were contacted by the study nurse at 48 hours and 7 days after study entry. SETTING: Adult tertiary care hospital with an emergency department managing 48,000 visits yearly in a metropolitan area of 250,000. PARTICIPANTS: Members of the study population referred to the emergency department for medical or surgical problems. Of 113 nursing home patients, blood culture results were available for 111. MAIN OUTCOME MEASURES: Blood cultures were obtained by standard protocol. Demographic and medical information was collected from the medical record. Three groups of patients were compared with respect to symptoms, risk factors, laboratory data, and outcome. RESULTS: Group 1 (n = 86) had two sets of negative blood cultures. Group 2 (n = 10) had true-positive cultures. Group 3 (n = 15) had false-positive cultures of Staphylococcus epidermidis. The prevalence of bacteremia was 9.8% in the study population. No risk factors were predictive of bacteremia. Great variation in signs and symptoms were noted in all three groups, none correlating with bacteremia. Although seven of the 10 patients with positive cultures were febrile, this association did not reach statistical significance. All groups had high admission (> 50%) and mortality (20% to 37%) rates. CONCLUSIONS: The prevalence of bacteremia in the nursing home population presenting to the emergency department was 9.8%. The symptoms and signs of bacteremia in this population were variable and nonspecific. The high rate of false-positive cultures in this setting is of concern.

Adult↗

Validation of an enzyme immunoassay for serodiagnosis of acute Q fever.

An enzyme immunoassay was validated for the serodiagnosis of acute Q fever. Minimum positive tests were determined for both serial dilutions and a single dilution of patient sera. To establish the specificity of the test, 152 serum samples were tested from individuals with no evidence of past Coxiella burnetii infection. Diagnostic titers were set at > or = 128 for the IgM and IgG responses to phase I, at > or = 512 for the IgM response to phase II and at > or = 1,024 for the IgG response to phase II Coxiella burnetii. These titers gave a false-positive rate of < or = 1%. Alternatively, testing a single dilution of sera (1:128) gave specificities ranging from 97.3 to 98.7%. Tests with the greatest sensitivities, using serially diluted early convalescent-phase sera, were the IgM (84%) and IgG (80%) responses to phase II Coxiella burnetii. At a single serum dilution, 92% of early convalescent sera had a positive IgG response to phase II Coxiella burnetii. With a high specificity and good sensitivity, the EIA can be used to diagnose acute Q fever with a single convalescent serum specimen. The duration of a positive response was greater than five years.

Coxiella burnetii↗

Q fever.

Explore the source record for details and available documents.

Animals↗

Legionellaceae in the potable water of Nova Scotia hospitals and Halifax residences.

Water was cultured from 39 of 48 hospitals (7 Halifax hospitals and 32 non-Halifax hospitals) in the province of Nova Scotia and from 90 residences (74 private dwellings, 16 apartments) in Halifax to determine the frequency of legionella contamination. Six of seven Halifax hospitals had Legionellaceae isolated from their potable water compared with 3 of 32 non-Halifax hospitals (P < 0.0001). Overall, 19 of 59 (32%) of the water samples from Halifax hospitals were positive for legionellae compared with 5 of 480 (1%) samples from non-Halifax hospitals (P < 0.0000). Five of the six positive Halifax hospitals had Legionella pneumophila serogroup 1 and 1 had L. longbeachae serogroup 2 recovered from their potable water. Legionella contamination was associated with older, larger (> or = 50 beds) hospitals with total system recirculation. These hospitals also had water with a higher pH and calcium content but lower sodium, potassium, nitrate, iron and copper content. Fourteen of the 225 (6.2%) water samples from Halifax residences were positive for legionellae -8% (6/74) of the single family dwellings were positive, compared with 25% (4/16) apartments. The positivity rate of 15.7% for the 19 electric hot-water heaters in Halifax homes was not significantly different from the 32% positivity for Halifax hospitals. L. longbeachae accounted for 2 of the 14 isolates of legionellae from Halifax homes.

Calcium↗

Increasing prevalence of Helicobacter pylori infection with age: continuous risk of infection in adults rather than cohort effect.

It remains unclear whether acquisition of Helicobacter pylori is due to a continuous risk of acquiring the infection or a cohort effect. In this prospective 3-year cohort study, the seroprevalence, conversion, and reversion of H. pylori infection as determined by IgG antibodies was examined. The cohort consisted of 316 randomly selected, nonpatient subjects aged 18-72 years who each provided at least 2 suitable samples. Seroprevalence of H. pylori increased from 21% in the third decade to 50% in the eighth decade. Crude annual seroconversion rate was 1% and the "spontaneous" seroreversion rate was 1.6%. Age was the only identified risk factor for H. pylori infection. A continuous risk of acquisition of 1%/year rather than a cohort effect best explains the pattern of H. pylori infection in this Canadian population. Seroconversion continues in adult life, and spontaneous reversions do occur, especially in the later decades.

Adult↗

Human and guinea pig immune responses to Legionella pneumophila protein antigens OmpS and Hsp60.

We studied the immune responses of guinea pigs and humans to two Legionella pneumophila antigens. Guinea pigs surviving a lethal intraperitoneal challenge dose of virulent L. pneumophila exhibited strong cutaneous delayed-type hypersensitivity (DTH) reactions to purified OmpS (28-kDa major outer membrane protein) and Hsp60 (heat shock protein or common antigen), while weak DTH reactions were noted for extracellular protease (major secretory protein [MSP] [ProA]) and no reaction was observed with an ovalbumin (OA) control. Lymphocyte proliferation responses (LPRs) were measured for peripheral blood and spleen lymphocytes from guinea pigs surviving sublethal and lethal challenge doses of L. pneumophila. Lymphocytes from uninfected animals showed no proliferation to Hsp60 or OmpS, while lymphocytes from sublethally and lethally challenged animals exhibited strong proliferative responses to Hsp60 and OmpS. Guinea pigs vaccinated with purified OmpS exhibited low antibody titers and strong DTH and LPRs to OmpS, whereas lymphocytes from animals vaccinated with Hsp60 exhibited weak DTH responses and high antibody titers to Hsp60. All guinea pigs immunized with OmpS survived experimental challenge with L. pneumophila (two of two in a pilot study and seven of seven in trial 2) versus zero of seven OA-immunized controls (P = 0.006 by Fisher's exact test). In three vaccine trials in which animals were vaccinated with Hsp60, only 1 guinea pig of 15 survived lethal challenge. Peripheral blood lymphocytes (PBLs) from humans with legionellosis showed stronger LPRs to OmpS than PBLs from humans with no history of legionellosis (P = 0.0002 by Mann-Whitney test). PBLs of humans surviving legionellosis exhibited a lower but highly significant proliferative response to Hsp60 (P < 0.0001 compared with controls by Mann-Whitney test). These studies indicate that OmpS and Hsp60 are important antigens associated with the development of protective cellular immunity. However, as determined in vaccine trial studies in the guinea pig model for legionellosis, the species-specific antigen OmpS proved much more effective than the genus-common Hsp60 antigen.

Animals↗

Virulence of patient and water isolates of Legionella pneumophila in guinea pigs and mouse L929 cells varies with bacterial genotype.

Thirteen isolates of Legionella pneumophila serogroup 1 (five from patients, eight from water) were screened for their virulence in guinea pigs after intraperitoneal injection and for their infectivity in L929 mouse cells. Since these isolates included three monoclonal antibody subtypes and four genotypes, the relative influence of these parameters on the pathogenicity of naturally occurring L. pneumophila could be assessed. There was no correlation between infectivity in the L929 assay and virulence for guinea pigs. The source of the isolate, patient or environmental, as well as the isolate's monoclonal antibody subtype did not correlate with virulence. At the p < 0.05 level, isolates with genotype IIb (20-MDa plasmid and EcoRI fragmentation pattern b) were significantly more virulent (mean log LD50 6.84) than genotype VIb (100-MDa plasmid, pattern b), IIId (72- and 96-MDa plasmids, pattern d) or Oc (no detectable plasmid, pattern c) isolates. Genotype IIId isolates were the least virulent (mean log LD50 9.49). Plasmid-containing isolates were more infective than plasmidless ones in L929 cells (p = 0.0001). We conclude that our strain types of L. pneumophila exhibit a gradation in virulence for guinea pigs and that infectivity in L929 cells does not correlate with virulence for guinea pigs.

Animals↗

Diverse populations of Legionella pneumophila present in the water of geographically clustered institutions served by the same water reservoir.

We cultured potable water from seven institutions (six hospitals and one medical school) every 2 weeks for 6 months for Legionella pneumophila. All of the institutions were located close to each other and received water from the same freshwater source. Two institutions (the medical school and hospital F, a maternity hospital) never had L. pneumophila isolated from their potable water. The remaining five had 17 to 72% of their water samples positive for L. pneumophila. Most of the isolates were serogroup 1; however, in hospital B serogroup 5 accounted for 56% of the isolates. Oxford and OLDA monoclonal antibody subtypes of L. pneumophila serogroup 1 coexisted in four of the five institutions, while subtype France only was found in one institution. All 10 isolates from this institution lacked plasmids. The other four institutions had Legionella populations with plasmid profiles II, III, and VI. Two of these institutions also had isolates with no plasmids. The distribution of the plasmid types was significantly different for all institutions except C and D. The distribution of monoclonal antibody subtypes was significantly different for L. pneumophila isolates recovered from institutions C and D. There were no characteristics that distinguished the culture-positive institutions from the culture-negative areas. We conclude that diverse populations of L. pneumophila exist within these institutions despite their geographic proximity and identical potable water source.

Cross Infection↗

In situ colonization of polyvinyl chloride, brass, and copper by Legionella pneumophila.

A sampling device (Robbins device) was used to expose brass, copper, and polyvinyl chloride plugs to potable water contaminated by Legionella pneumophila serogroup 1. Plugs were removed at approximately 1-week intervals and cultured. The colonization rates were polyvinyl chloride, 70; copper, 31; and brass, 25%. Quantitative cultures revealed that polyvinyl chloride was most heavily colonized, whereas brass was least colonized. We conclude that materials used in plumbing systems are readily colonized by Legionella and that the Robbins device provides a means for testing such materials in an in situ setting.

Bacterial Adhesion↗

Q fever in Sokoto, Nigeria.

There is very little information available about the prevalence of Coxiella burnetii in Africa. We obtained blood from 75 Nigerians hospitalized in Sokoto for a variety of acute medical conditions. Their age range was 7 months to 50 years; there were 39 males and 36 females. Antibody titers were determined to phase I and phase II C. burnetii antigens using a microimmunofluorescence test. Thirty-three (44%) had an antibody titer of greater than or equal to 1:8 to phase II C. burnetii. We conclude on the basis of this limited survey that Q fever is common in Nigeria.

Adolescent↗

Comparison of agar disk diffusion, microdilution broth, and agar dilution for testing antimicrobial susceptibility of coagulase-negative staphylococci.

A collection of 120 oxacillin-susceptible and 120 oxacillin-resistant coagulase-negative staphylococci (CNS) from six tertiary care hospital laboratories were tested by agar disk diffusion, three microdilution broth systems (Sensititre, Dynatech, and Alpkem), and the Vitek AutoMicrobic system for comparison with reference agar dilution results. The antimicrobial agents tested were oxacillin, cefazolin, cefotaxime, cefuroxime, cefamandole, fusidic acid, rifampin, and vancomycin. Incubation was at 30 or 35 degrees C for 24, 48, and 72 h. The broth media were supplemented with 2% NaCl for some antimicrobial agents, and the agar dilution method was used with and without the addition of 4% NaCl. The CNS were identified to species by the method of Kloos and Schleifer. The results showed a lack of concordance between two hospitals with respect to oxacillin susceptibility testing by agar dilution with no NaCl supplement. The reasons are not clear but may be related to variations in media. The 4% NaCl supplement or extended incubation to 48 h eliminated this difference. The cefazolin and cefotaxime susceptibility results in the agar disk diffusion test were unreliable if accepted at face value. Cefamandole testing correlated well with the reference method regardless of the method used, and salt supplementation is not recommended. Most of the oxacillin-resistant CNS were resistant to the other beta-lactam drugs except cefamandole. Of 22 CNS resistant to cefamandole, 21 were S. haemolyticus.

Anti-Bacterial Agents↗