Activities of various β-lactams and β-lactam/β-lactamase inhibitor combinations against Acinetobacter baumannii and Acinetobacter DNA group 3 strains

Acinetobacter baumannii and Acinetobacter DNA group 3 are members of the so-called A. calcoaceticus-A. baumannii complex and are important nosocomial pathogens. Multiresistance in these organisms is increasingly frequent, and alternative treatment options are needed. The beta-lactamase inhibitors clavulanate, sulbactam and tazobactam have intrinsic activity against Acinetobacter strains. In the present study, broth microdilution was used to assess the in-vitro activities of currently available beta-lactam/beta-lactamase inhibitor combinations and sulbactam alone against 469 Acinetobacter isolates (A. baumannii, n=395; Acinetobacter DNA group 3, n=74) collected from various laboratories in Germany. Fixed concentrations and fixed ratios of beta-lactamase inhibitors were used. Sulbactam-containing combinations (susceptibility rates of 90.4-92.7% for A. baumannii and 97.3-100% for Acinetobacter DNA group 3) and sulbactam alone were superior to clavulanate- and tazobactam-containing combinations. The activity of sulbactam-containing combinations against members of the A. calcoaceticus-A. baumannii complex was conferred exclusively by the intrinsic activity of the beta-lactamase inhibitor and did not result from enhanced beta-lactam activity. Testing with the inhibitor added at a fixed ratio of inhibitor to beta-lactam appeared to give more reliable results than testing at a fixed concentration of the inhibitor. Resistance to carbapenems (0.3%) remains low in Germany.

Antibacterial Resistance of Community- Acquired Respiratory Tract Pathogens Recovered from Patients in Germany and Activity of the Ketolide Telithromycin: Results from the PROTEKT Surveillance Study (1999–2000)

BACKGROUND

The Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin (PROTEKT) longitudinal global surveillance study examines the antibacterial susceptibility of community-acquired respiratory pathogens.

METHODS AND RESULTS

Data from isolates collected in Germany in 1999-2000 in the PROTEKT study show that 8.3% of pneumococcal isolates (n = 325) had reduced susceptibility to penicillin and 2.2% were fully resistant. Erythromycin resistance was 15.7% overall and particularly high in Leipzig (31.6%). All penicillin- and erythromycin-resistant strains were inhibited by telithromycin (MIC < or =0.5 mg/l) and linezolid (MIC < or =2 mg/l). Beta-lactamase was produced by 3.2% of Haemophilus influenzae (9/284) and 89.5% of Moraxella catarrhalis strains (111/124). All Streptococcus pyogenes isolates (n = 87) were susceptible to penicillin, although 9.2% were resistant to macrolides.

CONCLUSIONS

Penicillin resistance in Germany remains low; however, the prevalence of antimicrobial resistance among common respiratory pathogens is rising, particularly against macrolides. Continued surveillance is necessary to guide optimal empirical therapy, and new antimicrobials, like telithromycin, need to be developed with improved potency against target pathogens and low propensity for the development of resistance.

Long-Term Outcome and Quality of Care of Patients with Staphylococcus aureus Bacteremia

To assess the long-term outcome and influence of clinical management of patients with Staphylococcus aureus bacteremia (SAB), 229 patients with blood cultures positive for Staphylococcus aureus between January 1997 and December 2000 were retrospectively identified and followed up. Risk factors, source of infection, treatment, clinical course, and outcome were recorded by chart review. For the assessment of 1-year survival, a questionnaire was sent to family doctors and government registration offices. Time of initial antibiotic therapy, duration of antibiotic treatment and performance of echocardiography were regarded as indicators of the quality of the clinical management of SAB. Among the 229 patients studied, 218 were evaluable for 1-year survival. Crude mortality after 1 year was 37.6% year. Within 30 days 43 (19.7%) patients had died, and 39 (17.9%) additional patients died thereafter. Using multivariate analysis, the following variables were associated with death: malignant disease (odds ratio [OR] 4.8; 95% confidence interval [CI], 2.6-8.9), pneumonia (OR, 3.6; 95%CI, 1.2-10.2), age >60 years (OR, 2.6; 95%CI, 1.5-4.5), and known source of infection (OR, 2.3; 95%CI, 1.3-4.1). Among 160 patients with a completely assessable treatment course 73 (46%) had received antibiotics for at least 14 days. A delay of antibiotic treatment of 1 day or more after microbiological diagnosis was observed in 28.3% of patients (i.e., 60 of 212 patients who received at least 1 dose of antibiotics). Echocardiography was performed in 101 (44.1%) cases. Overall, the findings indicate that standard guidelines for the management of SAB are followed only in part in clinical practice. In order to reduce the considerable mortality associated with SAB and to improve short- and long-term outcome, efforts should be made to increase adherence to recommendations.

Combination therapy of disseminated Fusarium oxysporum infection with terbinafine and amphotericin B

A case of disseminated infection with Fusarium oxysporum following chemotherapy of acute myelogenous leukemia is reported. Antifungal treatment was successful with a 13-day course of oral terbinafine 250 mg t.i.d. in combination with amphotericin B deoxycholate 1.0-1.5 mg/kg qd and subsequently intravenous liposomal amphotericin B 5 mg/kg qd. Preceding monotherapy with amphotericin B deoxycholate 1.0-1.5 mg/kg qd had not stopped the progression of infection. The combination therapy described here represents a novel approach to the treatment of Fusarium spp. in the immunocompromised host in whom Fusarium spp. are known to cause disseminated infection with high mortality.

Right hemihepatectomy for bile duct injury following laparoscopic cholecystectomy

Laparoscopic cholecystectomy (LC) has become the treatment of choice for patients with symptomatic cholecystolithiasis. But with the introduction of this technique, the incidence of bile duct injuries has increased. We report the case of a 33-year-old man who was transferred from an affiliated hospital to our department for the treatment of a bile duct injury 2 weeks after LC. Prior to transfer, a laparotomy had been performed, with insertion of a T-tube and a Robinson drain on day 5 after LC. Endoscopic retrograde cholangiography (ERC) on admission day revealed an extensive defect of the right biliary system, which could not be treated endoscopically. An emergency laparotomy had to be performed at night for acute bleeding from the portal vein. Due to massive inflammation in the porta hepatis and intraparenchymal destruction of the right bile duct, liver resection was performed 2 days later, after the patient had stabilized in the intensive care unit (ICU). The patient had a prolonged postoperative course, but he finally recovered well from these operations. In conclusion, the management of bile duct injuries should include ultrasound to detect and drain fluid collections and ERC to classify the injury. Emergency laparotomy should never be performed without these examinations, since the majority of bile duct injuries can be treated endoscopically. Surgery for this serious complication should always be performed at specialized centers for hepatobiliary surgery.

Reduced risk for pancreatitis after endoscopic microtransducer manometry of the sphincter of Oddi: a randomized comparison with the perfusion manometry technique

BACKGROUND AND STUDY AIMS

Endoscopic microtransducer manometry of the sphincter of Oddi has been shown to be a reliable alternative to perfusion manometry for evaluating sphincter of Oddi motor function. It avoids volume loading of the biliopancreatic system, and may therefore be associated with a lower risk of inducing postmanometry pancreatitis.[nl]

PATIENTS AND METHODS

During a 2-year period, microtransducer manometry of the sphincter of Oddi was carried out in 215 patients (median age 42 years; 155 women; biliary study in 152 cases, additional pancreatic evaluation in 63 cases). Sphincter of Oddi manometry was conducted as the sole procedure in all patients. The frequency of pancreatitis was assessed prospectively and graded according to established guidelines. A total of 130 consecutive patients (median age 37 years, 92 women; 30 with biliary type II, 58 with type III, 34 with pancreatic type I, and eight with type II) were then randomly assigned to undergo microtransducer or perfusion manometry of the sphincter of Oddi in a standardized fashion.

RESULTS

During the initial 2-year period, nine cases of pancreatitis (a pancreatitis frequency of 4.2 %) were observed after microtransducer manometry, and most were of mild degree (six mild, two moderate, and one severe). No deaths occurred, and no surgical procedures were required. In the randomized part of the study, the demographic and clinical characteristics of the patients in both groups, as well as the technical aspects of the procedures performed, were well matched. The frequency of pancreatitis after microtransducer manometry was 3.1 %, compared with 13.8 % after perfusion manometry ( P < 0.05). Pancreatitis occurred in two patients after microtransducer manometry, and was mild in both cases. After perfusion manometry, mild pancreatitis occurred in six patients and moderate pancreatitis in three.

CONCLUSION

Endoscopic microtransducer manometry of the sphincter of Oddi is associated with a lower risk for postmanometry pancreatitis than standard perfusion manometry.

Clinical management of catheter-related infections

Central venous catheters represent a major source of nosocomial bloodstream infections, which cause considerable excess morbidity. It is currently unknown to what extent these infections contribute to mortality. Most catheter-related infections (CRIs) are caused by Gram-positive organisms (mainly coagulase-negative staphylococci). Definite diagnosis of CRI necessitates removal of the catheter in most cases. However, the recently described technique of differential time to positivity may allow diagnosis of CRI with the catheter left in place. Removal of the catheter has been standard clinical practice for the management of CRI in the past and is still recommended in many cases. In specific situations, such as infections of implanted catheters with coagulase-negative staphylococci, a trial of catheter salvage may be justified. In catheter-related bloodstream infection Staphylococcus aureus and Candida spp., the catheter should be removed immediately, due to the high risk of metastatic infection and increased mortality. A clinical work-up for the detection of additional foci (including transesophageal echocardiography in S. aureus infections) is advisable in these cases. All CRIs should be treated with antibiotics to which the causative agent has been shown to be susceptible. In addition to systemic antimicrobial therapy, antibiotic lock therapy may be applied, especially in patients with implanted long-term catheters if catheter salvage is attempted.

41-j�hriger Patient mit unklarem Fieber und Bakteri�mie mit Actinobacillus actinomycetemcomitans

A 41-year-old male patient presented with fever of unknown origin which had been present for 5 months. The primary diagnostic procedures did not identify an infectious focus. After a lag phase of 13 days, blood cultures became positive for Actinobacillus actinomycetemcomitans, which belongs to the HACEK group of microorganisms. According to the DUKE criteria, infective endocarditis was diagnosed despite negative transesophageal echocardiography (TEE). The sensitivity of TEE is estimated between 86 and 94%. An infected tooth was extracted as a possible focus, and the patient was treated with i.v. antibiotics for 5 weeks according to the guidelines of the AHA and ACC. The fever was permanently terminated, and the further course of the patient was uneventful. Despite negative TEE, the diagnosis "infective endocarditis" should not be rejected, and blood cultures should be grown for up to 30 days.

Measurement of day and night neutrino energy spectra at SNO and constraints on neutrino mixing parameters

The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is found to be 7.0%+/-4.9%(+1.3%)(-1.2%). A global solar neutrino analysis in terms of matter-enhanced oscillations of two active flavors strongly favors the large mixing angle solution.

Direct evidence for neutrino flavor transformation from neutral-current interactions in the Sudbury Neutrino Observatory

Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold of 5 MeV. The non-nu(e) component is phi(mu)(tau) = 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) x 10(6) cm(-2) s(-1), 5.3sigma greater than zero, providing strong evidence for solar nu(e) flavor transformation. The total flux measured with the NC reaction is phi(NC) = 5.09(+0.44)(-0.43)(stat)(+0.46)(-0.43)(syst) x 10(6) cm(-2) s(-1), consistent with solar models.

[Linezolid--a new antibiotic for treatment of methicillin resistant Staphylococcus aureus infections in trauma surgery? Report of 2 cases]

PROBLEM

Infections with Methicillin-resistant Staphylococcus aureus are reported increasingly in intensive care unit and ward, that means not only a dangerous disease but also a considerable expenditure factor.

METHODS

In trauma surgery we could observe the Linezolid treatment of 2 patients with a MRSA infection. After treatment with Vancomycin and further evidence of MRSA the application of Linezolid was continued during 3 weeks accompanied by further microbiologic investigations.

RESULTS

In a 73 year old man with humerus shaft fracture the MRSA osteomyelitis was eradicated with Linezolid (600 mg/day per os over 3 weeks) after radical débridement and reosteosynthesis. The MRSA pneumonia in a 14 year old girl was treated successfully by Linezolid (600 mg/day i.v. over 3 weeks) and pneumotherapy. Follow up excluded further MRSA infection.

CONCLUSIONS

Linezolid represents an efficient new reserve antibiotic. In case of pneumonia, severe skin and soft tissue infections good results can be expected. The treatment of osteomyelitis has been reported only in single cases.

A randomized monocentric trial in febrile neutropenic patients: ceftriaxone and gentamicin vs cefepime and gentamicin

A prospective, randomized, controlled monocentric trial was performed to evaluate the efficacy and safety of once daily ceftriaxone 2 g plus gentamicin 5 mg/kg in comparison to cefepime 2 g t.i.d. plus gentamicin 5 mg/kg q.d. in the treatment of neutropenic fever. In case of fever (oral temperature > or =38.5 degrees C on one occasion or > or =38.0 degrees C twice within 24 h) and a granulocytopenia (neutrophil count below 500 or below 1000/microl when expected to fall below 500 within 72 h), patients with hematological malignancies or solid tumors were assigned to ceftriaxone or cefepime, each with gentamicin. The primary endpoint was defined as defervescence on day 4-6 followed by at least 7 afebrile days. Secondary endpoints were overall response, defined as defervescence on day 28 and toxicity. Two hundred eleven episodes were included. Fever of unknown origin (FUO) accounted for 124 episodes (58.8%), microbiologically defined infection (MDI) for 39 (18.5%), clinically defined infection (CDI) for 25 (11.8%), and both clinically and microbiologically defined infection (CMDI) for 19 episodes (9%). On an intent-to-treat basis 207 episodes were evaluable for the primary endpoint. Ceftriaxone plus gentamicin and cefepime plus gentamicin were successful in 49.5% and 51%, respectively. Overall response was achieved on study day 28 in 92.5% and 91%, respectively. Diarrhea was more frequent with ceftriaxone/gentamicin (6.5% vs 17%), while nausea/vomiting was less (12.1% vs 5%). Once-daily ceftriaxone plus gentamicin was not inferior to cefepime t.i.d. plus gentamicin q.d. in the empirical treatment of neutropenic fever.

Transmural drainage of cystic peripancreatic lesions with a new large-channel echo endoscope

BACKGROUND AND STUDY AIMS

The availability of a new large-channel echo endoscope led us to develop a new needle-stent device for endoscopic puncture and drainage of pancreatogenic cystic lesions. The purpose of this study was to examine whether endoscopic ultrasound (EUS)-guided one-step 10-F puncture and drainage with the new equipment could be feasible and successful. The use of the technique and the short-term outcome in our first four patients are described and discussed.

PATIENTS AND METHODS

Cystic lesions were drained using the new technique in four patients. All the patients had symptomatic peripancreatic lesions, one with intrahepatic and one with intrasplenic extension. Punctures were carried out using a new echo endoscope with a 3.7 mm working channel and an Albarran lever. The 10-F transmural stents were placed over a 1 mm stainless steel needle and a 6-F Teflon catheter using a special assembly designed for controlled one-step placement and stent release.

RESULTS

Puncture and drainage were technically successful in two patients. In one patient, the 10-F component failed to pass the cystic wall. Drainage was successful in the same session using a 7-F one-step device. In one patient, no stent was placed, but the 1 mm needle was used for diagnostic tissue sampling during the procedure because of the suspicious cyst morphology. Surgical resection revealed a ganglioneuroma.

CONCLUSIONS

The new echo endoscope allows endoscopic interventions for peripancreatic cystic lesions under excellent endoscopic and EUS control. The Albarran lever was reliable and helpful for optimal direction of the needle. The new echo endoscope combined with special needle-stent devices was effective and safe for diagnosis and therapy in the first four cystic lesions. Cystic tumors must always be considered as a differential diagnosis in patients with apparently pancreatitis-induced cystic lesions.

Systemic inflammatory response syndrome in adult patients with nosocomial bloodstream infection due to Staphylococcus aureus

To determine the impact of methicillin resistance on clinical course and outcome, we evaluated nosocomial bloodstream infections (BSIs) due to Staphylococcus aureus that were diagnosed in 82 adult patients at the Medical College of Virginia Hospitals from December 1995 through May 1997. Patients with BSI due to methicillin-resistant S. aureus were compared with patients with BSI due to methicillin-susceptible S. aureus; the groups did not differ with regard to inflammatory response or outcome. Mortality was predicted by systemic inflammatory response and Acute Physiology and Chronic Health Evaluation II score but did not correlate with bacterial resistance to methicillin.

Advantages of short-lived positron-emitting radioisotopes for intracoronary radiation therapy with liquid-filled balloons to prevent restenosis

Balloon catheters filled with liquid radioisotopes provide excellent dose homogeneity for intracoronary radiation therapy but are associated with risk for rupture or leakage. We hypothesized that the safety of liquid-filled balloons may be improved once positron emitters with half-lives below 2 h are used instead of the high-energy beta-emitters 166Ho, 186Re, or 188Re, all of which have a longer half-life of at least 17 h.

METHODS

To support this concept, the suitability of 18F (half-life, 109.8 min), 68Ga (half-life, 67.6 min), 11C (half-life, 20.4 min), 13N (half-life, 9.97 min), and 15O (half-life, 2.04 min) for intracoronary radiation therapy was evaluated. Potential tissue penetration of positron radiation was assessed in a series of phantom experiments using Gafchromic film. Antiproliferative efficacy of positrons emitted by 68Ga was investigated in vitro using cultured bovine aortic smooth muscle cells (BASMCs), and was compared with gamma-radiation emitted by 137Cs. To characterize the remaining risk, we estimated radiotoxicity after accidental intravascular balloon rupture on the basis of tabulated isotope-specific doses (ICRP 53) and compared these values with 188Re.

RESULTS

Half-dose depth of tissue penetration measured in phantom experiments was 0.29 mm for 18F, 0.42 mm for 11C, 0.54 mm for 13N, 0.79 mm for 15O, and 0.9 mm for 68Ga. Irradiation of cultured BASMCs with positron radiation (68Ga) induced dose-dependent inhibition of proliferation with complete proliferative arrest at doses exceeding 6 Gy. ED(50) and ED(80) were 2.5 +/- 0.4 Gy (mean +/- SD) and 4.4 +/- 0.8 Gy, respectively. Antiproliferative efficacy was equal to that of the 662-keV gamma-radiation emitted by 137Cs (ED(50), 3.8 +/- 0.2 Gy; ED(80), 8.0 +/- 0.3 Gy). Estimates made for patient whole-body and organ doses were generally below 50 mSv/1.85 GBq for all investigated positron emitters. The same dose estimates for 188Re were 6-20 fold higher.

CONCLUSION

Among the studied radioisotopes, 68Ga is the most attractive source for liquid-filled balloons because of its convenient half-life, sufficient positron energy (2.92 MeV), documented antiproliferative efficacy, and uncomplicated availability from a radioisotope generator. The safety profile for 68Ga is significantly better than that of 188Re, which suggests this radioisotope should be evaluated further in preclinical studies.

Measurement of the rate of nu(e) + d --> p + p + e(-) interactions produced by (8)B solar neutrinos at the Sudbury Neutrino Observatory

Solar neutrinos from (8)B decay have been detected at the Sudbury Neutrino Observatory via the charged current (CC) reaction on deuterium and the elastic scattering (ES) of electrons. The flux of nu(e)'s is measured by the CC reaction rate to be straight phi(CC)(nu(e)) = 1.75 +/- 0.07(stat)(+0.12)(-0.11)(syst) +/- 0.05(theor) x 10(6) cm(-2) s(-1). Comparison of straight phi(CC)(nu(e)) to the Super-Kamiokande Collaboration's precision value of the flux inferred from the ES reaction yields a 3.3 sigma difference, assuming the systematic uncertainties are normally distributed, providing evidence of an active non- nu(e) component in the solar flux. The total flux of active 8B neutrinos is determined to be 5.44+/-0.99 x 10(6) cm(-2) s(-1).

Topical application of nitrates onto the papilla of Vater: manometric and clinical results

BACKGROUND AND STUDY AIMS

Systemic administration of nitrates inhibits motility of the sphincter of Oddi (SO) but is hampered by a decrease of the arterial blood pressure. We evaluate whether topical application of glyceril trinitrate (GTN) onto the papilla can facilitate cannulation of the common bile duct during routine endoscopic retrograde cholangiopancreatography (ERCP) and compare the effect of topical GTN with that of isosorbide dinitrate (ISDN) on SO motility.

PATIENTS AND METHODS

A total of 80 patients undergoing routine ERCP for suspected biliary obstruction received topical application of either saline (n = 40) or 10 mg of GTN (n = 40) onto the papilla of Vater in a randomized, double-blind fashion. Thereafter, selective bile-duct cannulation was attempted with a 0.035" hydrophilic guide wire. In another trial, 16 biliary type III patients underwent endoscopic SO-manometry and received in a randomized fashion either 10 mg of GTN (n = 8) or 10 mg of ISDN (n = 8) which was infused topically onto the papilla via the manometric catheter. Thereafter, the manometric recording was continued for a further 5 minutes.

RESULTS

A spontaneous opening of the papilla with concurrent transpapillary bile flow was observed in 24/40 patients after topical GTN, and in only 8/40 patients after topical saline (P < 0.01). However, neither the number of cannulation attempts nor the time until successful cannulation differed significantly between the groups. In addition, the pre-cut rate was nearly identical in the two groups. Topical GTN showed no significant influence on the mean arterial blood pressure. The SO-baseline pressure was significantly lowered by topical GTN (28.2+/-12.9 mm Hg before ISDN vs. 22.5+/-13.7 mmHg after P<0.01). The phasic SO motility was also strongly inhibited by both drugs. However, the effect of GTN completely wanes after 3 minutes, whereas ISDN inhibited SO motility for > 5 minutes in all patients.

CONCLUSIONS

Both topically administered GTN and ISDN evoked a profound inhibition of SO motility, but the effect of ISDN was longer lasting than that of GTN. However, locally administered GTN did not facilitate selective bile-duct access during routine ERCP.

Adsorption of PCDD/F on MWI fly ash

The removal of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) from waste incinerator off-gas is a costly task, because a considerable part of the PCDD/F may exist in the gas phase (often 50-100% around 200 degrees C). The volatile fraction passes the particle filter and the subsequent gas cleaning equipment, so that an additional unit is needed to remove the gaseous PCDD/F from the flue gas. Moreover, dioxins and furans can accumulate in some parts of the equipment in a way that they can act as a latent source. In this work, we investigate the possibility to adsorb the PCDD/F at the fly ash particles and to remove them during the filtration. The gas/particle partitioning of the PCDD/F depends on the temperature, the vapor pressure, the particle size, the particle number density and on the physical and chemical properties of the particle surface. These relationships are investigated by model calculations and by pilot scale experiments (500 Nm3/h) which employ one selected hexachlorinated dioxin congener. At room temperature, approx. 90% of the HxCDD are found in the particulate phase, while at 135 degrees C that portion is only 10%. This means that at ambient temperatures, the gas/particle partitioning of the dioxin corresponds well to the sublimation equilibrium. At higher temperatures, it is much different from the sublimation equilibrium and the apparent adsorption enthalpy is smaller than the enthalpy of sublimation. This observation is in agreement with literature data. From the above experiments and from similar literature data, the efficiency of fly ash particles as a sink for PCDD/F can be evaluated. The data suggest that the adsorption rate is not the limiting factor for the transfer into the particulate phase. The important factors appear to be the chemical composition of the fly ash and the temperature.

Randomized controlled monocentric comparison of once daily ceftriaxone with tobramycin and cefotaxime three times daily with tobramycin in neutropenic fever

A prospective, randomized, controlled monocentric trial was performed to evaluate the efficacy and safety of once daily ceftriaxone 2 g plus tobramycin 5 mg/kg in comparison to cefotaxime 2 g t.i.d. plus tobramycin 5 mg/kg qd in the treatment of neutropenic fever. In cases of fever > or = 38.5 degrees C and a neutrophil count below 1000/microliter, patients with hematological malignancies were assigned to ceftriaxone or cefotaxime, each with tobramycin. The primary endpoint was defined as defervescence < 37.5 degrees C on day 4-6 followed by at least 7 afebrile days. Secondary endpoints were overall response, defined as defervescence on day 25 and toxicity. There were 160 episodes of 114 patients included. Fever of unknown origin accounted for 79 episodes (51%), microbiologically defined infection for 36 (23%), clinically defined infection for 27 (17%), and both clinically and microbiologically defined infection for 14 episodes (9%). On an intent-to-treat basis 156 episodes could be evaluated for the primary endpoint. Ceftriaxone plus tobramycin and cefotaxime plus tobramycin resulted in a primary response in 46.9% and 45.3%, respectively. Overall response was achieved on study day 25 in 87.7% and 80%, respectively. No significant difference in toxicity was observed. Once-daily ceftriaxone plus tobramycin was not inferior to cefotaxime t.i.d. plus tobramycin qd in the empirical treatment of neutropenic fever.

Fate of antimony in municipal solid waste incineration

The average antimony concentration in municipal solid waste is estimated to be about 10-60 ppm. Thermodynamical models predict a volatile behavior for antimony compounds, yet literature mass balances show that about 50% of the antimony input remains in the grate ashes. This fact can be explained by the formation of thermally stable antimonates in the fuel bed due to interactions with alkali or earth-alkali metals. Thermogravimetric experiments revealed an increased thermal stability for antimony oxide in presence of oxygen and calcium oxide. Spiking experiments on the test incinerator TAMARA showed that chlorination processes have a strong effect on antimony volatilization whereas high fuel-bed temperatures and addition of antimony oxide only have a moderate effect. In the grate ashes, antimony shows a pH-depending leaching property, which is typical for anionic species. This fact supports the thesis that antimony is present in the grate ashes in an anionic speciation.

Effects of flue gas composition on the catalytic destruction of chlorinated aromatic compounds with a V-oxide catalyst

When using catalytic flue gas cleaning, several flue gas compounds may influence oxidation reactions of hazardous volatile organic compounds, possibly leading to lower reaction rates and, thus, to an incomplete destruction. Experimental investigations were performed with regard to the influence of selected flue gas compounds, like hydrogen chloride, sulfur dioxide, oxygen, and water vapour, on the catalytic destruction behavior of chlorobenzenes under flue gas cleaning conditions of an incineration plant. For this purpose, a metal oxide catalyst was operated at different temperatures at a space velocity of 3600 h-1 in a laboratory-scale fixed bed reactor with model flue gases, and with real flue gases generated from the TAMARA waste incineration plant. The results obtained from the studies with model flue gas were analyzed with respect to reaction kinetics. These kinetics were applied for comparison with the experimental data gained in the real flue gas.

Angiotensin-converting enzyme gene insertion/deletion polymorphism and carotid artery wall thickness in patients with peripheral arterial occlusive disease

BACKGROUND

It has been suggested that the deletion polymorphism of the angiotensin converting enzyme (ACE) gene is linked to a high risk of cardiovascular disease. The relationship between the insertion/deletion (I/D) polymorphism of the ACE gene and the carotid intima-media thickness in patients with peripheral arterial occlusive disease is unknown. We tested the hypothesis that the early progression of atherosclerosis in the extracranial carotid arteries in patients with peripheral arterial disease is associated with a genetic predisposition.

METHODS

This prospective trial included 98 patients who only had manifestations of arteriosclerotic disease in peripheral arterial vascular regions of the lower extremities (stable stage II PAOD). Maximal common carotid intima-media thickness (mIMT) was measured using high resolution B-mode ultrasonography. Determinations of ACE gene polymorphism were made using a polymerase chain reaction technique. Multivariate regression analysis was performed to assess the influence of ACE genotypes, ACE activity and vascular risk factors on intima-media thickness.

RESULTS

There was no significant association between intima-media thickness and ACE gene polymorphism. History of symptomatic peripheral arterial disease without local or systemic progression exists in subjects with the II-genotype significantly longer than in subjects with the DD genotype (p=0.01). With the presence of an II-genotype, there was also a tendency towards a thinner intima-media thickness. We found significant correlations between intima-media thickness and age (p<0.0001), fasting serum insulin (p=0.001), and lipoprotein (a) (p=0.008).

CONCLUSIONS

In the present study involving patients with stage II peripheral arterial occlusive disease, ACE gene polymorphism could not be identified as a determining marker for the development of intima-media thickening in the common carotid artery. However, it can be assumed that there is a reduced risk for the systemic progression of atherosclerosis in patients with the II genotype.

[Reduction of the radiation exposure of patients caused by selected interventional and angiographic procedures]

PURPOSE

To reduce patient doses caused by selected interventional and angiographic procedures using the digital C-arm unit "Multiskop".

MATERIALS AND METHODS

After a patient study done previously, physical measurements with test phantoms were carried out, and physical-technical parameters such as distance between focus and image intensifier, additional filtration, and radiation dose per image were optimised. Then, the dose-area product (DAP) and the fluoroscopic time were measured for 130 percutaneous transluminal angioplasties (PTA), 40 PTA with stent implantation, 61 embolisations, and 302 digital subtraction angiographies (DSA). In the case of 16 PTA, 9 embolisations, and 38 DSA the number of radiographs was determined, and the DAP was divided into two parts, fluoroscopy and radiography. The measuring values were compared with data of the patient study done previously.

RESULTS

The median values of the DAP and the fluoroscopic time amounted to 25 Gy cm2 and 9.7 min for PTA, 97 Gy cm2 and 8.5 min for PTA with stent implantation, 88 Gy cm2 and 17.2 min for embolisation as well as 54 Gy cm2 and 2.8 min for DSA. For the relation between DAP caused by fluoroscopy and radiography, and the number of radiographs, median values of 0.76 and 63 for PTA, 0.81 and 123 for embolisation as well as 1.85 and 134 for DSA were determined. In comparison to the patient study done previously the median values of the DAP were reduced by 31% for PTA, 26% for PTA with stent implantation, 55% for embolisation, and 38% for DSA.

CONCLUSIONS

The comparison between the patient studies done previously and recently indicates the great potential of dose reduction for interventional and angiographic procedures. Although the X-ray equipment is ten years old the patient dose can be reduced by organizational and physical-technical modifications to such an extent that preliminary national reference dose values will not be exceeded. For further significant dose reductions while maintaining adequate image quality it will be necessary to purchase a modern X-ray equipment with pulsed fluoroscopy and automatic filter selection.

Endoscopic injection of botulinum toxin in patients with recurrent acute pancreatitis due to pancreatic sphincter of Oddi dysfunction

AIM

To evaluate the technical feasibility, safety, and short-term efficacy of botulinum toxin injection for pancreatic sphincter of Oddi dysfunction and to analyse whether the symptomatic response to botulinum toxin might be a predictor of outcome for endoscopic sphincterotomy.

METHODS

Fifteen consecutive patients (nine female, aged 38 +/- 12 years) with frequent attacks (median four) of acute pancreatitis within 6 months, and manometrically proven pancreatic sphincter of Oddi dysfunction underwent endoscopic injection of 100 units of botulinum toxin into the major papilla. All patients underwent prospective follow-up thereafter and in cases of recurrent pancreatitis manometry this was repeated and pancreatic sphincterotomy was performed.

RESULTS

No side-effects occurred after botulinum toxin injection in any patient. Within 3 months after botulinum toxin treatment, 12 out of 15 patients remained asymptomatic (80% primary response). Only one out of three patients without symptomatic benefit showed continued elevated pancreatic sphincter pressure at manometry and only this patient benefited from pancreatic sphincterotomy later on. Eleven of the 12 patients initially responding to botulinum toxin injection developed a symptomatic relapse 6 +/- 2 months after botulinum toxin treatment. These patients then achieved long-term clinical remission from pancreatic or combined (biliary and pancreatic, n=5) sphincterotomy (median follow-up, 15 months).

CONCLUSION

Endoscopic botulinum toxin injection into the papilla of Vater is a safe procedure for treatment of pancreatic sphincter of Oddi dysfunction that may provide short-term relief in about 80% of the patients. Those patients who respond to botulinum toxin may subsequently gain definitive cure from sphincterotomy.

[Radiation exposure to patients caused by single-photon transmission measurement in PET]

AIM

The aim of the study was the determination of the radiation exposure to the patient caused by single-photon transmission measurement for 3D whole-body PET.

MATERIAL AND METHOD

Single-photon-transmission measurement is performed using two Cs-137 point-sources (E gamma = 662 keV, A = 2*614 MBq) on a 3D PET scanner (ECAT ART). During a simulation of a whole body transmission scan (axial length: 75 cm, 6 contigous bed positions) dose measurements with thermoluminescent dosimeters were carried out using a thorax and an abdomen phantom. Following the guidelines of the ICRU report No. 60 an estimation of the effective dose caused by a single-photon transmission measurement was calculated.

RESULTS

For a total acquisition time of 360 min (6 beds with an acquisition time of 60 min per bed) the absorbed doses amounted to: surface (xyphoid) 189 microGy, heart 196 microGy, lungs 234 microGy, vertebra 240 microGy, liver 204 microGy, gonads 205 microGy, thyroid 249 microGy and bladder 185 microGy resulting in a conversion factor of 1.7*10(-4) mSv/(h*MBq). The estimation of the effective dose for a patient's transmission (acquisition time of 3.2 min per bed) yields a value of 11 microSv. An estimation of the ratio of the conversion factors for transmission measurements in single-photon- and in coincidence mode (two Ge-68/Ga-68 rod sources of 40 MBq each), respectively, resulted in a value of 0.18. The comparison of the effective doses caused by single-photon transmission and by emission measurement (injection of 250 MBq of FDG) yields a ratio of 2.3*10(-3).

CONCLUSION

The radiation exposure of the patient caused by the transmission measurement for 3D whole-body-PET can be neglected. In comparison with the coincidence-transmission using uncollimated line sources of low activity the radiation exposure is still reduced using single photon trans-mission with collimated point sources of high activity.

Manometrically-guided endoscopic injection of botulinum toxin for esophageal achalasia: a pilot trial

AIMS

Some patients gained only short-term response (< 6 months) after botulinum toxin (BTX) injection for achalasia. This may be due to an incorrect site of injection when targeting the lower esophageal sphincter by using endoscopic landmarks only.

PATIENTS AND METHODS

7 elderly patients (4 females, 67 +/- 20 years) with classical achalasia received manometrically-guided botulinum toxin injection by means of a double-channel endoscope. Thereafter, they were clinically re-evaluated at 6 weeks and later on at bi-monthly intervals.

RESULTS

The mean symptom score decreased 6 weeks after the manometrically-guided BTX-treatment from 12 +/- 2 (before BTX) to 6 +/- 2 points (p = 0.02). However, according to the study criteria one patient did not respond to BTX-injection and underwent subsequent cardiomyotomy. The LES-resting pressure was found not to be altered in this patient (6 weeks after BTX-injection) but manometry revealed a marked decrease of the LES-tone in 3 other patients who benefitted from BTX-injection. 5 of the 6 patients, who initially benefited from BTX-injection, relapsed 10 months (range, 6-13 months) after their initial BTX-treatment. They all were treated with repeated BTX-injections. At completion of the study (1.5-year follow-up) the mean symptom score of the 6 patients was still significantly lower (6 +/- 2 points) than before study entry (p = 0.03).

CONCLUSION

Manometrically-guided endoscopic BTX-injection is a simple, safe and highly effective (during 1.5-year follow-up) technique for treatment of esophageal achalasia. With the manometrically-guided injection technique one may obtain a longer lasting symptomatic response than with the traditional method of BTX-application.

Sedation with propofol plus midazolam versus propofol alone for interventional endoscopic procedures: a prospective, randomized study

AIM

Adequate patient sedation is mandatory for most interventional endoscopic procedures. Recent anaesthesiologic studies indicates that propofol and midazolam act synergistically in combination and therefore may be superior to sedation with propofol alone in terms of sedation efficacy, recovery and costs (due to a presumed lower total dose of propofol needed).

METHODS

A total of 239 consecutive patients undergoing therapeutic EGD or ERCP (EGD/ERCP-ratio, 1:1) randomly received either propofol alone (n=120, group A, loading dose 40-60 mg intravenously, followed by repeated doses of 20 mg) or propofol plus midazolam (n=119, group B, initial midazolam dose of 2. 5-3.5 mg intravenously, followed by repeated doses of 20 mg of propofol) for sedation. Vital signs (heart rate, blood pressure, oxygen saturation, electrocardiogram) were continuously monitored. Procedure-related parameters, the recovery time and quality (post-anaesthesia recovery score) as well as the patient's co-operation and tolerance to the procedure (visual analogue scale) were prospectively assessed.

RESULTS

Patients of group A and B were well matched with respect to demographic and clinical data, endoscopic findings, and the type of associated procedures. In group A, a mean dose of 0.25 +/- 0.13 mg.min/kg propofol was used compared to 0.20 +/- 0.09 mg.min/kg of propofol in group B (P < 0.01, plus additional 2.9 +/- 0.5 mg of midazolam). Clinically relevant changes in vital signs were observed at comparable frequencies with a lowering of the systolic blood pressure < 90 mmHg in six out of 119 patients in group B and one out of 120 patients in group A (P=0.07). The sedation efficacy was rated similarly in both groups, whereas the mean recovery time (group A, 19 +/- 7 min vs. group B, 25 +/- 8 min, P < 0.05) as well as the recovery score (post-anaesthesia recovery score group A, 8.0 +/- 1.1 vs. post-anaesthesia recovery score group B, 7.3 +/- 1.2, P < 0.001) were significantly better with propofol alone than with propofol plus midazolam.

CONCLUSION

During therapeutic endoscopy, sedation with propofol and midazolam requires a lower total dose of propofol, but otherwise has no superior sedation efficacy and is associated with a slower post-procedure recovery than sedation with propofol alone.