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W V Kern

Publications and source records attributed to W V Kern.

At least 37 records · Page 2Linked to original sources
PubMed2004

Antibiotic use in Germany and European comparison.

In view of increasing rates of antibiotic resistance worldwide and decreased research and development of new antibacterial compounds, programmes helping to better understand the complex relationship between antibiotic consumption and emergence of resistance have gained importance. Consequently, in addition to increased support for research projects that establish prospective surveillance and evaluation of antibiotic resistance and antimicrobial drug use, the EU has passed directives addressing political leadership in this respect. Information on antibiotic use in Germany is now available from databases independent from cost-oriented market research studies. This information allows estimation of antibiotic use in ambulatory and hospital care as compared with to other EU countries. According to results of current projects, the frequency of national antibiotic use in ambulatory care in Germany (4948 defined daily doses per 1000 population per year) falls within the lower third of EU countries. Upper boundaries in regional variation in antibiotic use are still much lower than values for high-use countries like France, Spain and Portugal. Hospital antibiotic use, in contrast, appears to be in the range of that reported for other countries. However, only rough estimates of hospital antibiotic use are available for Germany as well as most other EU countries due to data usually derived from non-representative hospital sampling.

Animals↗
PubMed2004

Update on glycopeptide use in german university hospitals.

BACKGROUND: A previous study has shown considerable variation in glycopeptide use from 1992 through 1994 among four university hospitals in southern Germany. Active antimicrobial management in one of the hospitals was associated with the containment of glycopeptide consumption in the medical and surgical service at < 1.5 defined daily doses (DDD)/100 patient days in the subsequent period. In the present study, more recent data on comparative glycopeptide use in German university hospitals were analyzed. MATERIALS AND METHODS: Hospital pharmacy records from 1998 through 2000 were evaluated. The number of DDD (definition according to the World Health Organization [WHO]/Anatomic and Therapeutic Classification [ATC] index) per 100 patient days was calculated to compare glycopeptide use in different medical and surgical service areas between eight German university hospitals. RESULTS: The 3-year averages in recent glycopeptide use for the eight hospitals ranged between 1.3 and 8.8 DDD/100 patient days in the medical services, and between 0.7 and 1.8 DDD/100 patient days in the surgical services. Only one of the eight hospitals showed medical service glycopeptide use of < 1.5 DDD/100 patient days. In most hospitals, glycopeptide use was higher in the medical intensive care units (ICU) (median 8.6; range 4.3 to 12 DDD/100 patient days, data for the year 2000) than in the surgical ICUs (median 6.7; range 1.2 to 8.6 DDD/100 patient days, data for the year 2000). High use was also observed for hematology-oncology services (median 7.5; range 2.7 to 15.7 DDD/100 patient days, data for the year 2000). CONCLUSION: These recent data from a larger hospital sample confirm large variations in glycopeptide use, identify hematology-oncology services as a significant prescribing source along with ICUs, and indicate areas of probable overuse of glycopeptide antibiotics. The data may be useful as a benchmark for further focused drug use control interventions.

Anti-Bacterial Agents↗
PubMed2003

Antimicrobial therapy of unexplained fever in neutropenic patients--guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO), Study Group Interventional Therapy of Unexplained Fever, Arbeitsgemeinschaft Supportivmassnahmen in der Onkologie (ASO) of the Deutsche Krebsgesellschaft (DKG-German Cancer Society).

Cytostatic chemotherapy of hematological malignancies is often complicated by neutropenia, which increases the risk of infections, especially if the neutrophil count is below 500/microl. Frequently, fever is the first, and in most patients the only, sign of an infection. Unexplained fever is defined as follows: temperature of >/=38.3 degrees C or >/=38.0 degrees C for at least 1 h, or measured twice within 12 h, if the neutrophil count is <500/microl or <1000/microl with predicted decline to 500/microl. Different risk categories can be identified according to the duration of neutropenia: low risk </=5 days, intermediate risk 6-9 days, high risk >/=10 days. An empirical mono- or duotherapy with antipseudomonal and antistreptococcal agents should be initiated immediately. In the low risk patient group, oral therapy with cipro-, levo-, or ofloxacin combined with amoxicillin/clavulanic acid is permissible. For standard and high risk patients, monotherapy can be carried out with either ceftazidime, cefepime, piperacillin with tazobactam or a carbapenem. In duotherapy, a single dose of an aminoglycoside is combined with acylaminopenicillin or a cephalosporin of the third or fourth generation. The addition of glycopeptides in empirical therapy should only be considered in the presence of severe mucositis, or if a catheter-associated infection is suspected. If fever persists after 72-96 h of first-line therapy with antibiotics, the regimen should be modified (with the exception of e.g. coagulase-negative staphylococci infections, because these infections take longer to respond). Intermediate risk patients should additionally receive an aminoglycoside after monotherapy (penicillin or a cephalosporin). If a carbapenem was administered for monotherapy, this can be followed by a quinolone and/or a glycopeptide. In the high risk group, the same modifications should be made as in the intermediate risk group but with additional systemic antifungal treatment. In the presence of unexplained fever, fluconazole can be administered at first, but if this fails, amphotericin B (conventional or liposomal), itraconazole, voriconazole or caspofungin should be started. After defervescence to <38 degrees C, treatment should be continued for 7 days if the neutrophil count is <1000/microl, and for 2 days if the neutrophil count is >1000/microl.

Anti-Bacterial Agents↗
PubMed2003

Vancomycin versus placebo for treating persistent fever in patients with neutropenic cancer receiving piperacillin-tazobactam monotherapy.

This prospective, double-blind trial assessed whether the addition of a glycopeptide would be able to reduce the time to defervescence in neutropenic patients with cancer who had persistent fever 48-60 h after the initiation of empirical piperacillin-tazobactam monotherapy. Of 763 eligible patients, 165 with persistent fever were randomized to receive piperacillin-tazobactam therapy plus either vancomycin therapy or placebo. Defervescence was observed in 82 (95%) of 86 patients in the vancomycin group and in 73 (92%) of 79 patients in the placebo group (P=.52). The distributions of the time to defervescence were not statistically significant between the 2 groups (estimated hazard ratio, 1.03; 95% confidence interval, 0.75-1.43; P=.75). The number of additional episodes of gram-positive bacteremia and the percentage of patients for whom amphotericin B was empirically added to their therapy regimen were also similar in both groups. This study failed to demonstrate that the empirical addition of vancomycin therapy to the treatment regimen is of benefit to persistently febrile neutropenic patients with cancer.

Adolescent↗
PubMed2002

Glycopeptide use at four university hospitals in southern Germany.

BACKGROUND: Excessive use of glycopeptide antibiotics may enhance the risk of glycopeptide resistance among enterococci and staphylococi, but there is little data on the use of these antibiotics in German hospitals. METHODS: Hospital pharmacy records for the years 1992 to 1994 were evaluated. The number of defined daily doses (DDD) per 100 patient days was calculated to compare glycopeptide use between four state university hospitals. At one of the hospitals with comparatively low glycopeptide usage but an active antimicrobial management program, data were prospectively evaluated for 1995 to 2000 to assess the variation of glycopeptide use over time. RESULTS: The 3-year averages in glycopeptide use for the four hospitals ranged between 1.03 and 3.14 DDD/100 patient days. In all four hospitals, glycopeptide use was higher in the medical service (range, 1.59-7.26) than in the surgical service (range, 0.66-4.39). Active antimicrobial management in one of the hospitals was associated with containment of glycopeptide consumption in the medical and surgical service at < 1.5 DDD/100 patient days in the last 3 years. CONCLUSION: Glycopeptide use differs considerably at tertiary care hospitals in southern Germany, but use of < 1.5 DDD/100 patient days in both surgical as well as medical tertiary care hospital departments appears achievable.

Anti-Bacterial Agents↗
PubMed2001

Prediction of gram-negative bacteremia in patients with cancer and febrile neutropenia by means of interleukin-8 levels in serum: targeting empirical monotherapy versus combination therapy.

In a prospective observational study of 133 neutropenic episodes, interleukin (IL)-8 serum levels > 2000 pg/mL at the onset of fever had a sensitivity of 53% and a specificity of 97% as a predictor of gram-negative bacteremia (GNB; positive predictive value, 73%; negative predictive value, 94%). The rates of early death differed significantly between patients with high and those with low IL-8 levels (3/11 vs. 1/122; P< .01). Serum IL-8 levels at the onset of fever define a low-risk subgroup of patients who can safely be treated with monotherapy.

Adolescent↗
PubMed2001

Practices of infectious disease prevention and management during hematopoietic stem cell transplantation: a survey from the European group for blood and marrow transplantation.

Protocols for the prevention of infections after allogeneic or autologous hemopoietic stem cell transplantations are usual. A questionnaire was sent out to the members of the European Group for Bone and Marrow Transplantation (EBMT) in the spring of 1999. A total of 308 questionnaires from 180 centers were returned. Both allogeneic and autologous transplantation was reported from 128 centers, and allogeneic or autologous transplantation alone from four and 48 centers, respectively. Hemopoietic stem cell transplantation is still a domain of university hospitals. Intensive measures of isolation are usual. Allotransplantation is commonly performed in single rooms with HEPA-filtered air on special wards. However, even in the autologous setting, extensive measures of isolation are commonly used. This observation could be explained by historical developments and by the fact that nearly all centers for allogeneic transplantation perform both allogeneic and autologous transplantations, and thus similar measures are used in both settings. Other measures are usual but heterogeneous due to lack of clinical trials in this field. Drug prophylaxis during transplantation is mostly carried out with quinolones, TMP/SMZ, fluconazole, acyclovir, and pentamidine. Differences in drug prophylaxis after engraftment and in the use of different venous accesses do reflect the requirements after engraftment and discharge of patients from the transplant unit. The intensity of measures in autologous stem cell reinfusion does not reflect the development during the last decade. For cost effectiveness and convenience, it is necessary to abolish senseless measures. It is necessary to investigate anti-infectious strategies separately for allogeneic transplantation and other modalities of anti-cancer treatment in future.

Anti-Infective Agents↗
PubMed2001

Risk assessment and risk-based therapeutic strategies in febrile neutropenia.

Different approaches have developed over time regarding the empirical antimicrobial therapy of fever in neutropenic patients. The use of intravenous antibiotics remains the standard approach. Clinical criteria and 'low-risk' prediction rules have been developed that help select patients in whom oral therapy is well tolerated and who may be eligible for outpatient management. Comorbidity and clinical status at presentation remain important criteria in the risk-assessment process. Outpatient management requires additional assessment of non-medical criteria. Patients without documented infection and who have responded to initial therapy may benefit from simplified therapy such as a switch to oral drugs and/or outpatient management. Discontinuation of therapy may be considered in selected cases. Risk assessment in neutropenic patients with persistent unexplained fever is challenging. Available data suggest that broadening of the antibacterial coverage is of limited value. Instead, definition of the risk of fungal infection by using clinical criteria, imaging and laboratory studies, as well as the identification of those patients likely to benefit from antifungal therapy, appear to be of critical importance.

Administration, Oral↗
PubMed2001

Enhanced expression of the multidrug efflux pumps AcrAB and AcrEF associated with insertion element transposition in Escherichia coli mutants Selected with a fluoroquinolone.

The development of fluoroquinolone resistance in Escherichia coli may be associated with mutations in regulatory gene loci such as marRAB that lead to increased multidrug efflux, presumably through activation of expression of the AcrAB multidrug efflux pump. We found that multidrug-resistant (MDR) phenotypes with enhanced efflux can also be selected by fluoroquinolones from marRAB- or acrAB-inactivated E. coli K-12 strains having a single mutation in the quinolone-resistance-determining region of gyrA. Mutant 3-AG100MKX, obtained from a mar knockout strain after two selection steps, showed enhanced expression of acrB in a reverse transcriptase PCR associated with insertion of IS186 into the AcrAB repressor gene acrR. In vitro selection experiments with acrAB knockout strains yielded MDR mutants after a single step. Enhanced efflux in these mutants was due to increased expression of acrEF and associated with insertion of IS2 into the upstream region of acrEF, presumably creating a hybrid promoter. These observations confirm the importance of efflux-associated nontarget gene mutations and indicate that transposition of genetic elements may have a role in the development of fluoroquinolone resistance in E. coli.

Anti-Infective Agents↗
PubMed2000

Early detection of aspergillus infection after allogeneic stem cell transplantation by polymerase chain reaction screening.

Invasive aspergillosis (IA) has become a major cause of mortality in patients after allogeneic stem cell transplantation. To assess the potential of prospective polymerase chain reaction (PCR) screening for early diagnosis of IA, 84 recipients of an allogeneic stem cell transplant were analyzed with the investigators blinded to clinical and microbiologic data. Of 1193 blood samples analyzed, 169 (14.2%) were positive by PCR. In patients with newly diagnosed IA (n=7), PCR positivity preceded the first clinical signs by a median of 2 days (range, 1-23 days) and preceded clinical diagnosis of IA by a median of 9 days (range, 2-34 days). Pretransplantation IA (relative risk [RR], 2.37), acute graft-versus-host disease (RR, 2.75), and corticosteroid treatment (RR, 6.5) were associated with PCR positivity. The PCR assay revealed a sensitivity of 100% (95% confidence interval [CI], 48%-100%) and a specificity of 65% (95% CI, 53%-75%). None of the PCR-negative patients developed IA during the study period. Thus, prospective PCR screening allows for identification of patients at high risk for subsequent onset of IA.

Adolescent↗
PubMed2000

Modifications of therapy.

Rates of response to empirical therapy in the neutropenic patient with fever, range between 40 and 90%. Modifications of therapy are needed in patients who do not respond but may also be considered in patients who respond. In patients with unexplained fever and rapid defervescence, switch to oral therapy is an acceptable option and there is no need to continue the regimen until neutrophil recovery. Neutropenic patients with persistent undefined fever and those with progressive pneumonia benefit from the addition of antifungals while the empiric addition of a glycopeptide is unlikely to be effective. In patients with gram-negative bacterial infection initially treated with monotherapy, response may be increased after the addition of an aminoglycoside. In cases of a defined etiology, the institution of narrow-spectrum antimicrobials in a persistent neutropenic patient carries a substantial risk for superinfection and is not generally recommended. Improved diagnostic tools and sensitive clinical risk-assessment methods will allow selecting and targeting therapy modifications better.

Anti-Infective Agents↗
PubMed2000

Prospective screening by a panfungal polymerase chain reaction assay in patients at risk for fungal infections: implications for the management of febrile neutropenia.

Invasive fungal infections are a major cause of mortality in neutropenic cancer patients. To determine whether a polymerase chain reaction (PCR)-based assay enabled the identification of patients at risk for invasive fungal infections, a prospective monitoring once per week was performed during 92 neutropenic episodes in patients receiving chemotherapy for acute leukaemia or high-dose therapy followed by allogeneic or autologous stem cell transplantation, with the investigators blinded to clinical and microbiological data. PCR positivity was documented in 34 out of 92 risk episodes. All patients developing proven invasive fungal infection were found PCR positive, and PCR was found to be the earliest indicator of invasive fungal infection preceding clinical evidence by a mean of 5.75 d (range 0-14 d). In febrile neutropenic patients without a prior history of invasive fungal infection, a sensitivity of 100% and a specificity of 73% of the PCR assay for the development of proven or probable invasive fungal infection was documented. In conclusion, panfungal PCR performed prospectively once a week enabled the identification of patients at high risk for invasive fungal infections.

Acute Disease↗
PubMed2000

Severe Chlamydia pneumoniae infection in patients with neutropenia: case reports and literature review.

Three cases of life-threatening C. pneumoniae infection in patients with acute leukemia and treatment-induced neutropenia are described. Diagnosis was made on the basis of the detection of C. pneumoniae-DNA, complemented by serology. The role of the widely distributed respiratory tract pathogen C. pneumoniae in febrile neutropenia is poorly understood, and studies are needed to estimate the frequency of severe pulmonary infection caused by this agent in patients with neutropenia.

Adolescent↗