Paul B. Iannini

Spontaneous bacterial peritonitis: A review of 28 cases with emphasis on improved survival and factors influencing prognosis

During a five year period, 28 episodes of spontaneous bacterial peritonitis were documented. The number of cases recognized annually increased during the study period. Clinical and laboratory features of spontaneous bacterial peritonitis were similar to those previously reported; however, mortality was considerably lower (57 per cent). Factors associated with adverse prognosis were increasing hepatic encephalopathy, more than 85 per cent granulocytes in peripheral blood or ascitic fluid, total bilirubin greater than 8 mg/dl and serum albumin less than 2.5 g/dl. Temperature greater than 38 degrees C was associated with increased survival. Infection by enteric organisms was associated with higher mortality than infection by nonenteric organisms. Unexpectedly, patients with bacteremia fared no worse than those whose blood remained sterile. The data suggest that in patients with leukocyte counts greater than 1,000 cells/mm3 and more than 85 per cent granulocytes in their ascitic fluid, the likelihood of spontaneous bacterial peritonitis is high. Such patients deserve empiric antibiotic therapy pending the results of appropriate cultures.

Nationwide study of the susceptibility of the Bacteroides fragilis group in the United States.

A nationwide susceptibility survey of the Bacteroides fragilis group was continued at New England Medical Center in 1983. A total of 555 strains were obtained from eight centers in the United States. In addition to the nine antimicrobial agents studied in the two previous years, three other agents were added to the evaluation: cefamandole, cefuroxime, and cefonicid. The results for the strains tested with the original nine drugs in 1983 were compared with those for 1,292 isolates tested in 1981 and 1982. The most active beta-lactam drug was piperacillin, which had an 8% resistance rate. Cefoxitin resistance increased from 10% in 1982 to 16% in 1983. High rates of resistance to cefotaxime, cefoperazone, cefamandole, cefonicid, and cefuroxime were encountered. No metronidazole- or chloramphenicol-resistant isolates were found during the 3 years of the study. Susceptibility patterns varied at the eight hospitals: the outbreak of cefoxitin resistance reported in 1982 at New England Medical Center remitted, while a high clindamycin resistance rate was documented at one hospital in 1983. These data indicate the need for determining the susceptibility patterns for the B. fragilis group of organisms at each hospital.

Susceptibility of the Bacteroides fragilis group in the United States in 1981.

The minimal inhibitory concentrations of nine antimicrobial agents was determined for over 750 clinical isolates of the Bacteroides fragilis group of anaerobic bacteria collected from nine centers in the United States during 1981. High resistance rates were documented for cefoperazone, cefotaxime, and tetracycline. Cefoxitin had the best activity of the beta-lactam antibiotics, whereas moxalactam and piperacillin had good activities. The resistance rate for clindamycin was 6%. There were no metronidazole- or chloramphenicol-resistant isolates encountered. There were significant differences in susceptibility among the various species of the B. fragilis group, particularly with moxalactam, cefoxitin, and clindamycin. Clustering of clindamycin-, piperacillin-, and cefoxitin-resistant isolates was observed at different hospitals. The variability of resistance rates with the beta-lactam antibiotics and clindamycin indicates that susceptibility testing of significant clinical isolates should be performed to define local resistance patterns.

Antimicrobial susceptibilities of 1,292 isolates of the Bacteroides fragilis group in the united states: comparison of 1981 with 1982

A susceptibility survey of 537 strains of the Bacteroides fragilis group from eight centers in the United States was continued at the Tufts New England Medical Center in 1982. The results were compared with those of 755 organisms analyzed in 1981. Nine antimicrobial agents were tested by an agar dilution method. The respective percentages of resistance for 1981 and 1982 were as follows (%): cefoxitin, 8 and 10; moxalactam, 22 and 12; cefotaxime, 54 and 48; cefoperazone, 57 and 54; piperacillin, 12 and 7; clindamycin, 6 and 3; metronidazole, 0 and 0; chloramphenicol, 0 and 0; and tetracycline, 63 and 59. Regional differences in resistance rates were found. Declines in resistance to moxalactam, piperacillin, and clindamycin were noted at the participating hospitals. An outbreak of cefoxitin resistance was noted at the Tufts New England Medical Center, where the rate increased from 14 to 30%. The various species of the B. fragilis group had differing patterns of resistance; B. fragilis was the most susceptible species. Significant cross resistance among the beta-lactam agents was found. These data indicate the need to determine the susceptibility patterns of the B. fragilis group organisms within each hospital.

Gatifloxacin-Associated Corrected QT Interval Prolongation, Torsades de Pointes, and Ventricular Fibrillation in Patients with Known Risk Factors

Drugs not commonly considered to be cardioactive agents have been reported to cause prolongation of the corrected QT interval with resultant torsades de pointes or ventricular fibrillation. We report 4 cases of gatifloxacin-associated cardiac toxicity in patients with known risk factors for this adverse event.

Gatifloxacin-induced QTc prolongation and ventricular tachycardia.

Prolongation of the QTc interval has been associated with antimicrobial agents such as erythromycin and trimethoprim-sulfamethoxazole, and additive effects can result when they are combined with other agents that prolong cardiac repolarization. The increase in proarrhythmic potential when terfenadine is combined with erythromycin is an example of competition for cytochrome P450 metabolism, leading to the accumulation of cardiotoxic levels of both drugs. The withdrawal of cisapride and grepafloxacin from the market because of cardiac arrhythmia highlights concern for the cardiac effects of noncardiac drugs. The fluoroquinolones can cause varying degrees of QTc prolongation, with a decreasing rank order of sparfloxacin, grepafloxacin, moxifloxacin, levofloxacin, gatifloxacin, and ciprofloxacin. The presence of an amino group at the C-5 position on the basic pharmacore of the fluoroquinolones (e.g., sparfloxacin) prolongs QTc to a greater extent than a methyl group at this position (e.g., grepafloxacin); the least amount of QTc prolongation is associated with a hydrogen atom at this position, present in all other fluoroquinolones. The proarrhythmic potential of fluoroquinolones does not correlate directly with the degree of prolongation of QTc interval. Few reports of ciprofloxacin-associated ventricular tachycardia exist, despite high-volume usage. Emerging recognition of the potential for multifocal ventricular tachycardia or torsades de pointes and other arrhythmias has been generated by reports involving sparfloxacin, grepafloxacin, and, most recently, levofloxacin. 5 We report a case that illustrates some of the key concepts emphasized in the well-done article by Owens in this issue of Pharmacotherapy.

Reassuring safety profile of moxifloxacin.

NOTE. Data from clinical trials are from [3]; data from postmarketing observationalstudies (PMOS) are on file. ADR, adverse drug reaction. Reprints or correspondence: Dr. Vladimir Krčmery, St. Elizabeth and University of Trnava Cancer Institute, Heyduková 10, 812 50 Bratislava, Slovak Republic (krcmery@spamba.sk). Clinical Infectious Diseases 2001; 32:1110–2 2001 by the Infectious Diseases Society of America. All rights reserved. 1058-4838/2001/3207-0021

Direct costs in patients hospitalised with community-acquired pneumonia after non-response to outpatient treatment with macrolide antibacterials in the US.

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Treatment of Respiratory Infections with Quinolones

AbstractIntroduction: Antibacterial cost-containment programmes emphasise the use of narrow-spectrum generic agents whenever possible. The use of these agents is driven by their lower purchase prices; the consequences of treatment failure are rarely considered. This study was conducted to identify the costs of treating patients hospitalised with community-acquired pneumonia (CAP) associated with Streptococcus pneumoniae following failure to respond to outpatient treatment with macrolide antibacterials. Methods: A multicentre, retrospective, observational study was performed in patients with CAP due to S. pneumoniae who were admitted to 31 North American hospitals following a lack of response to ≥2 days of outpatient treatment with a macrolide antibacterial. Direct medical costs (year 2004 values) of infection-related hospital resources, including antibacterials (purchase, preparation, dispensing, administration and monitoring), diagnostic tests, therapeutic procedures, treatment of adverse events and therapeutic failures, and hospitalisation per diem (ward, critical care and ventilator days), were analysed. Total hospital costs were then compared with standard diagnosis-related group (DRG) reimbursement. Results: A total of 122 patients were enrolled. Patients were frequently bacteraemic (52%) and infected with macrolide-resistant strains of S. pneumoniae (71%). Initial inpatient antibacterial treatment was not successful in 17 patients (14%) and seven patients (5.7%) died. The mean length of stay was 8.7 days (SD 7) including 1.3 days (SD 2.9) in a critical care unit and 1.4 days (SD 4.4) of mechanical ventilation. The mean cost of hospitalisation was

Imipenem/cilastatin: general experience in a community hospital

US12 678 (SD 13 346) but standard DRG reimbursement averaged only