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W V Kern

Publications and source records attributed to W V Kern.

72 records · Page 4Linked to original sources
PubMed1996

Release of soluble tumor necrosis factor receptors in Mediterranean spotted fever rickettsiosis.

Tumor necrosis factor alpha (TNF) is a key cytokine in the defense against many intracellular pathogens, including Rickettsia conorii, the causative agent of Mediterranean spotted fever (MSF). The levels of two soluble TNF receptors (sTNFR-p55 and sTNFR-p75), the extracellular domains of the two cell surface receptors for TNF, were elevated in the acute-stage plasma samples from 20 patients with serologically confirmed MSF. The median values were 3.1 and 7.8 ng/ml for sTNFR-p55 and sTNFR-p75, respectively. sTNFR values correlated significantly with plasma TNF concentrations. Patients with severe MSF had higher values for both receptor fragments than patients with nonsevere disease. The differences were statistically significant for sTNFR-p55 (median, 5.8 versus 2.0 ng/ml; P = 0.008). Given the proportionately higher values for both TNF and sTNFR-p55 in patients with severe MSF, the sTNFR-p55/TNF ratios for the two patient subgroups did not differ (P = 0.5), while the sTNFR-p75/TNF ratios were significantly different (P = 0.01), with disproportionately lower values in patients with severe disease.

Boutonneuse Fever↗
PubMed1994

Liposomal doxorubicin in AIDS-related Kaposi's sarcoma: long-term experiences.

Treatment of AIDS-related Kaposi's sarcoma with cytotoxic chemotherapy is limited by toxicities of the various agents. Liposomal doxorubicin is a new treatment option for patients with Kaposi's sarcoma with potentially reduced toxicity. Three AIDS patients with different stages of tumor risk were enrolled in a study evaluating the safety and efficacy of liposomal doxorubicin at a dose of 10-20 mg/m2 every 2-4 weeks. Maximal duration of treatment was 86 weeks with a cumulative dose of 560 mg/m2. Criteria proposed by the AIDS Clinical Trials Group were used to define tumor stages and response to therapy. All patients showed partial responses after 40-100 mg/m2 total dose with reduction of tumor-associated edema and flattening of more than 50% of previously nodular or plaque-like lesions. One patient showed progressive disease after discontinuation of treatment for 8 weeks; Kaposi's sarcoma responded again partially on retreatment. Progression was also seen in one patient after dose reduction due to granulocytopenia and again during treatment of active cytomegalovirus retinitis. Serial measurements of cutaneous target lesion surface area did not indicate response. Increases in surface area, however, correlated with progressive disease. Toxicities included moderate leukopenia, aphthous stomatitis, and transient alopecia. Liposomal doxorubicin may well be valuable for long-term treatment of AIDS-associated Kaposi's sarcoma, especially in patients with extensive disease. However, controlled comparison with conventional treatment regimens is mandatory.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Low incidence of invasive fungal infections after bone marrow transplantation in patients receiving amphotericin B inhalations during neutropenia.

The incidence of invasive fungal infections after bone marrow transplantation (BMT) was analyzed in 303 consecutive marrow graft recipients (allogeneic n = 271, autologous n = 27, syngeneic n = 5). All patients received inhalations with amphotericin B (10 mg twice daily) during neutropenia. The overall incidence of invasive fungal infections within the first 120 days after transplant was 3.6% (11/303; aspergillosis: 6; yeast infection: 5). Four of the 11 cases occurred early, and seven cases were observed after neutrophil recovery and discontinuation of amphotericin B inhalation treatment. Late infection was significantly associated with the development of acute graft-versus-host disease. Four of the 11 infections (early 2/4; late: 2/7) were observed in patients with a history of previous fungal infection. Other patient and treatment characteristics were not helpful in defining potential risk factors. In particular, the incidence of invasive fungal infections did not differ between patients with more or less strict reverse isolation measures. Occasional side effects such as initial mild cough and bad taste were rare, usually disappeared during continued administration, and were in no case the reason for discontinuation of treatment. These data suggest that aerosolized amphotericin B may be a useful, convenient, and efficient prophylactic antifungal regimen in BMT.

Administration, Inhalation↗
PubMed1994

Bacteremia due to fluoroquinolone-resistant Escherichia coli in two immunocompromised patients.

Two patients with acute leukemia developed Escherichia coli bacteremia while receiving oral ofloxacin for antibacterial prophylaxis during profound neutropenia. The isolates were resistant to ofloxacin (MIC 25 and 12.5 micrograms/ml respectively), other fluoroquinolones and several unrelated agents. Whole cell drug accumulation studies with four different fluoroquinolones suggested major differences between drugs but only minor alterations in individual drug permeability in the two resistant isolates compared with a susceptible control strain. In a supercoiling assay using the purified DNA gyrase and plasmid pBR322, high concentrations (> or = 250 micrograms/ml) of both ofloxacin and ciprofloxacin were needed for visible inhibition of enzyme activity suggesting mutations in the DNA gyrase gene as the significant mechanism of resistance in both strains.

Acute Disease↗
PubMed1994

A randomized trial of roxithromycin in patients with acute leukemia and bone marrow transplant recipients receiving fluoroquinolone prophylaxis.

Fluoroquinolone prophylaxis in patients with profound neutropenia may be useful for preventing gram-negative bacterial infection, but it is ineffective against gram-positive bacterial infections in the bloodstream, particularly those caused by streptococci and coagulase-negative staphylococci, which appear to have emerged as significant causes of morbidity, decreased treatment efficacy, and the increased costs of empiric antimicrobial therapy. In a prospective, randomized, open trial, we evaluated the efficacy and safety of oral roxithromycin (150 mg twice daily) as additional antibacterial prophylaxis in 131 adult patients with acute leukemia and bone marrow transplant recipients receiving oral ofloxacin. In comparison with patients given ofloxacin alone, fewer patients receiving ofloxacin plus roxithromycin developed bacteremia caused by viridans group streptococci (incidence, 9 versus 0%; P = 0.03), while the incidence of bacteremia caused by other organisms, the incidence of febrile episodes from any cause, the risk of infection-associated complications (including prolonged or secondary fever, pneumonia, septic shock, need for mechanical ventilation, and/or infection-related death), and antimicrobial usage for therapy were comparable between both groups. Adverse events possibly related to the study drugs were slightly more common among the patients receiving the combination treatment (P = 0.05). Although effective for the prevention of streptococcal bacteremia, the addition of roxithromycin to a fluoroquinolone should not be used routinely as a prophylactic regimen in patients with profound neutropenia, but it might be considered and may be useful for cancer patients with a particularly high risk of streptococcal infection and related complications.

Acute Disease↗
PubMed1994

Emergence of fluoroquinolone-resistant Escherichia coli at a cancer center.

Prophylactic treatment with fluoroquinolones of patients with profound neutropenia has been found to be useful for preventing gram-negative bacteremia and has become a standard preventive-therapy strategy in many cancer centers, but the development of bacterial resistance is a cause of concern. During the past few years, we have observed an increasing number of patients with leukemia from whom fluoroquinolone-resistant strains of Escherichia coli were isolated. The increase was significant in this patient population, and among patients with other underlying diseases, the rates of isolation of such strains per number of discharges were significantly lower and did not increase. Most of the leukemia case patients (16 of 19) had been pretreated with an oral quinolone (ofloxacin), with cumulative doses until the first isolation of a resistant E. coli strain ranging from 0 to 97.8 g (median, 14.4 g). Repeated isolation of such strains was seen in 8 of 17 patients during a follow-up period of > or = 4 weeks and in 1 of 6 patients during a follow-up period of > or = 16 weeks. Ten patients developed bacteremia (mortality, 1 of 10). On the basis of the number of patients with leukemia admitted to the hematology-oncology service, the incidence of bacteremia caused by fluoroquinolone-resistant E. coli increased from < 0.5% in 1988-1989 and 0.8% in 1990-1991 to 4.5% in 1992-1993 (P < 0.01). MICs for nine isolates obtained from cultures of blood from different patients ranged between 8 and 16 microgram/ml (ciprofloxacin and PD 131628), 8 and 32 microgram/ml (ofloxacin and BAY Y 3118), and 16 and 32 microgram/ml (sparfloxacin) and indicated resistance to trimethoprim-sulfamethoxazole, ampicillin, doxycycline, and chloramphenicol. Of nine isolates obtained from cultures of blood from different patients and that were subjected to genomic DNA typing by pulsed-field gel electrophoresis of XbaI digests, seven were typeable. Among these, four different genotypes were identified, suggesting both the independent development and the horizontal spread of resistant clones of E. coli.

Anti-Infective Agents↗
PubMed1993

Once-daily versus thrice-daily dosing of netilmicin in combination with beta-lactam antibiotics as empirical therapy for febrile neutropenic patients.

In a prospective, randomized trial, netilmicin given once daily (OD) was compared in terms of efficacy and safety with the conventional 8-hourly dosing regimen (TD), both in combination with a broad spectrum beta-lactam, as initial empirical therapy for febrile neutropenic patients; the total daily dosage of netilmicin in each group was 6 mg/kg body weight. Twenty-nine of the 116 (25%) evaluable patients had microbiologically documented septicaemia, most of which were caused by Gram-positive bacteria, 41 (35%) had microbiologically documented infection without bacteraemia and 46 (40%) had possible infection. Highest peak serum concentrations of netilmicin in the OD group were significantly higher and trough serum concentrations significantly lower than in the TD group. A multivariate analysis revealed that neither the dosage regimen nor the peak serum concentration of netilmicin were determinants of a favourable outcome. The response rates of both groups to the initial treatment regimens were comparable and increased similarly following modification of the initial therapy. Response rates were particularly poor in patients with lower respiratory tract infection and in those who remained neutropenic throughout the course of treatment. The incidence of nephrotoxicity was low and did not differ significantly between groups. Once-daily dosing of netilmicin appears to be as effective and as safe as thrice-daily dosing, but is unlikely to further improve the response of febrile neutropenic patients to empirical therapy.

Anemia, Aplastic↗
PubMed1993

Circulating tumor necrosis factor alpha (TNF), soluble TNF receptors, and interleukin-6 in human subacute bacterial endocarditis.

Cell surface components of viridans streptococci and enterococci have been shown to stimulate the release of tumor necrosis factor alpha (TNF) and interleukin-6 from monocytes/macrophages. In the sera from 10 patients with subacute enterococcal or streptococcal endocarditis, however, the levels of both cytokines were low or undetectable, with elevated TNF levels on admission in 3 patients with complicated disease. Soluble TNF receptor levels were significantly elevated compared with those of healthy controls. When patients with malaria were used as a control group of acute intravascular infection with high circulating TNF values, the ratio between soluble TNF receptors and TNF on admission was significantly greater in the patients with subacute bacterial endocarditis. Besides different amounts of circulating TNF, enhanced TNF receptor shedding may have an important role in the pathogenesis of subacute versus acute clinical disease following human intravascular infection.

Adult↗
PubMed1993

Single-drug oral antibacterial prophylaxis with ofloxacin in BMT recipients.

We evaluated the efficacy and safety of a new oral fluoroquinolone, ofloxacin (200 mg twice daily), as antibacterial prophylaxis after BMT in a non-comparative prospective study of patients nursed in either LAF plastic isolators or HEPA filtered single rooms. Of the 101 evaluable patients who were neutropenic (< 500 x 10(6)/l) for a median duration of 20 days, 92 (91%) had febrile episodes of varying length and causes. Infections were documented in 34 patients, of whom 14 had proven bacterial infection (13 with bacteremia and one with pneumonia). Mortality rate within 6 weeks after transplant was 6%. Only one patient died from bacterial infection. Univariate analysis using an array of potentially prognostic factors including the type of isolation was not helpful in identifying significant variables for predicting the development of documented infection. Tolerance was excellent. Oral ofloxacin was associated with a relatively low incidence of documented bacterial infection and related mortality, although it did not obviate the need for frequent empiric antimicrobial therapy due to a high incidence of febrile episodes.

Administration, Oral↗
PubMedDate not supplied

Ochrobactrum anthropi bacteremia: report of four cases and short review.

Ochrobactrum anthropi, formerly "Achromobacter" CDC group Vd, is a nonfermentative, nonfastidious gram-negative bacillus, that only recently has been given attention as a potential human pathogen. Over a 2-year period, we observed four patients with multiple blood cultures that were positive for the organism. The patients had acute leukemia as underlying disease, and presented with clinical and microbiologic features consistent with catheter-related bacteremia. In three of the patients the infection initially appeared to be unrelated to chemotherapy-associated profound neutropenia and occurred early after, or was the reason for, hospital admission. The antimicrobial susceptibility of the isolates varied: unlike previously reported cases, resistance in some of our isolates included aminoglycosides, newer fluoroquinolones, and trimethoprim-sulfamethoxazole. Despite in vitro susceptibility to imipenem in initial isolates, treatment of two patients with this agent obviously failed to eradicate the organism, and the patients either relapsed with bacteremia shortly after discontinuation of treatment or remained persistently febrile and bacteremic. O. anthropi appears to be increasingly recognized as a human opportunist pathogen associated with intravascular catheters and unpredictable multiple antibiotic resistance.

Adult↗
PubMedDate not supplied

Kinetics and correlation with body temperature of circulating interleukin-6, interleukin-8, tumor necrosis factor alpha and interleukin-1 beta in patients with fever and neutropenia.

Interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF) are important mediators of fever and inflammation, and are involved in the pathogenesis of sepsis. There is only limited data on serum concentrations of these proinflammatory cytokines in patients with fever and neutropenia, and their interrelationship and correlation with body temperature and clinical disease early in the febrile response during neutropenia have not been studied. Immunoreactive TNF, IL-1 beta, IL-6, and IL-8 in serum samples serially obtained from 14 adult patients with neutropenia and fever considered or documented to be due to infection were measured. IL-6 and Il-8 were consistently elevated in all patients, and correlated well with each other and with body temperature. Median peak concentration of IL-6 and IL-8 were 400 pg/ml (range: 100 to 41,000 pg/ml), and 1,025 pg/ml (range: 600 to 26,000 pg/ml), respectively, and levels of both cytokines rapidly declined in patients responding to antimicrobial therapy. Despite frequent sampling before and after the temperature peaks TNF and IL-1 beta, conversely, were less frequently detectable, with median peak values of < 10 pg/ml (range: < 10 to 150 pg/ml) for TNF, and 17 pg/ml (range: < 10 to 36 pg/ml) for IL-1 beta, respectively. The role of neutro- and monocytopenia with depletion of important cytokine producing and target cells in this particular cytokine response pattern needs to be further studied.

Acute Disease↗
PubMedDate not supplied

Colonization and infection with fluoroquinolone-resistant Escherichia coli among cancer patients: clonal analysis.

Escherichia coli with high-level fluoroquinolone resistance were isolated from feces and/or various body sites of 16 cancer patients who were on oral fluoroquinolone prophylaxis. Population analysis of fecal isolates in 11 patients showed that fluoroquinolone-resistant E. coli was the only aerobic gram-negative bacillus present and exhibited a relatively homogenous fluoroquinolone MIC distribution. Molecular typing by pulsed field gel electrophoresis of chromosomal DNA digests or by random amplified polymorphic DNA fingerprinting confirmed the clonal nature of gastrointestinal tract colonization with E. coli. Genotyping of ten colonies picked from the same fecal culture demonstrated identical strains in four of four patients examined. Identical genotypes from the same patient were isolated over prolonged periods of time in 12 of 12 cases examined, with one patient (with the longest follow-up of 14 months) who lost his initial genotype and became persistently colonized with a new genotype. In the 11 patients who developed infection due to fluoroquinolone-resistant E. coli, molecular typing also indicated that fecal colonization was associated with, and presumably preceded infection due to an indistinguishable genotype of fluoroquinolone-resistant E. coli.

Anti-Infective Agents↗
PubMedDate not supplied

An analysis of interleukin-8, interleukin-6 and C-reactive protein serum concentrations to predict fever, gram-negative bacteremia and complicated infection in neutropenic cancer patients.

A prospective study was performed to assess the potential value of interleukin (IL)-8, IL-6, and C-reactive protein (CRP) serum levels to predict fever, gram-negative bacteremia and complicated infection in neutropenic patients with cancer. Serum samples were obtained three times a week during 208 neutropenic episodes following cytotoxic chemotherapy. Fever of any cause developed during 104 out of 191 evaluable episodes. Serum levels of neither cytokine nor CRP were predictive of fever within more than 24 h before its onset. Unlike CRP, both IL-6 and IL-8 serum levels were significantly different between microbiologically documented infections and unexplained fevers. The highest values of IL-6 and IL-8 were observed in episodes of gram-negative bacteremia. Using receiver-operating-characteristic curves, the analysis of cytokine levels measured around the onset of fever indicated that IL-8 is potentially useful for predicting gram-negative bacteremia, with a high negative predictive value of > 90% and a moderate positive predictive value of 50% (sensitivity, 70%; specificity, 91%). In patients with persistent fever, predictions of further clinical complications, defined as prolonged fever of more than 7 days' duration, pneumonia, shock and/or death due to infection, were best predicted by IL-6. With an IL-6 cutoff value of 250 pg/ml in samples obtained 8 to 32 h after onset of fever, the positive predictive value was 92%, the negative predictive value 91% (sensitivity, 85%; specificity, 95%). The positive predictive value of IL-6 in samples obtained another 24 h later from patients still febrile remained > 90%, but the negative predictive value dropped to 47%. In any of the analyses, the predictive values of CRP levels were poor and inferior to either cytokine. These findings may have clinical value in identifying subgroups of patients requiring different therapeutic approaches.

Adolescent↗
PubMedDate not supplied

Antimicrobial expenditures and usage at four university hospitals. Baden-Württemberg Interuniversity Study Group.

BACKGROUND: The increasing use of antimicrobiaL drugs is resulting in enormous hospital expenditures. Careful assessment of inappropriate prescribing and a search for more cost-effective treatment strategies are urgently required. Comparisons between hospitals should help identify areas of inappropriate prescribing as well as effective drug use programs, but such analyses may be severely biased if the impact of different case-mixes is not recognized. PATIENTS AND METHODS: We studied antimicrobial usage and expenditures at four state university hospitals in southwestern Germany and assessed the significance of differences between hospital services after adjustment for patient variables. A prevalence survey was done with review of 2,254 charts of patients admitted to the surgical, medical and pediatric services to obtain information on antimicrobial drug prescription and expenditures in the week preceding the survey. RESULTS: According to pharmacy data for the year 1994, maximal differences between these hospitals in the antibiotic costs per patient-day were 1.9-fold (surgical services), 1.5-fold (medical services), and 1.6-fold (pediatric services). In a multivariate analysis, adjusted antibiotic prescription prevalence rates did not differ for medical and pediatric service patients, but did differ for surgical service patients (p = 0.03). Similarly, adjusted expenditures per patient-week differed significantly between hospitals for surgical service patients (p = 0.001), but only marginally for medical (p = 0.14) and pediatric (p = 0.05) service patients. The adjusted difference in expenditures between surgical departments was as large as 2.8-fold (95% CI 1.8 to 4.3) and was primarily related to preferential use of expensive iv antimicrobial drugs. CONCLUSION: In two hospitals, lowest expenditures in either surgery or medicine were associated with active antimicrobial drug use programs suggesting an impact of these programs on drug use and expenditures limited to these services. The identification of such large patient-mix unrelated differences in antimicrobial usage and expenditures offers opportunities for quality improvements and cost reduction.

Adolescent↗