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Objectives: The aims of this study were to evaluate risk factors, clinical presentation, outcome and antimicrobial susceptibility in patients with Escherichia coli bacteremia occurring over seven years in a single cancer hospital., Methods: Sixty five episodes of bacteremia from E. coli appearing over seven years from 12,301 admissions in a single cancer institution were retrospectively analyzed., Results: The proportion of bacteremia caused by E. coli among Gram-negative bacteremia was 20.8% (the second most common organism after Pseudomonas aeruginosa), and infection-associated mortality was 17%. The incidence in 1989-1995 varied from 14.3 to 24.7%. The most common risk factors were: solid tumors as the underlying disease (70.7%); central venous catheter insertion (32.3%); prior surgery (46.2%), and prior chemotherapy within 48 h (44.4%). Neutropenia and urinary catheters did not place patients at high risk in any of the subgroups. When we compared the two subgroups of 61 cases of bacteremia - monomicrobial and polymicrobial (when E. coli was isolated from blood culture with another microorganism) - we found that acute leukemia and breakthrough (recurrence while receiving antibiotics) bacteremia were more frequently associated with polymicrobial E. coli bacteremia. There was also a difference in infection-associated mortality: monomicrobial bacteremia due to E. coli only had a significantly lower mortality in comparison with polymicrobial E. coli bacteremia (8.9 vs 35.0%, respectively; P<0.03)., Conclusion: The susceptibility of 115 E. coli strains isolated from 65 episodes of bacteremia was stable. Only two episodes caused by quinolone-resistant strains occurred, both in 1995, after six years of using ofloxacin for prophylaxis in neutropenic patients in our hospital. We found that 85.2-91.3% of all strains were susceptible to aminoglycosides, 97.8% to quinolones, and 90-100% to third generation cephalosporins and imipenems. The patients most commonly infected had solid tumors and the mortality was only 17%.

The risk factors, therapy and outcome of ten cases of fungemia due to Candida krusei, appearing during the last 10 years in a single national cancer institution, are analyzed. Univariate analyses did not find any specific risk factors in comparison to 51 Candida albicans fungemias appearing at the same institution and with a similar antibiotic policy. Association with prior fluconazole prophylaxis was not confirmed because only one case appeared in a patient previously treated with fluconazole. However, attributable and crude mortality due to C. krusei fungemias was higher than for C. albicans fungemia. The authors review 172 C. krusei fungemias published within the last 10 years to compare with the incidence, therapy and outcome of C. krusei fungemia from our cancer institute.

Objective: The aim of the study was to assess the outcome of inappropriately treated cancer patients with documented bacteremia., Design/setting: 95 cases of inappropriately treated bacteremias in febrile cancer patients in a tertiary-care center were analyzed and compared with a group of appropriately treated bacteremias to assess risk factors for inappropriate therapy and outcome., Results: Among 285 bacteremias, 95 (33.3%) were not treated appropriately, with 42 receiving the wrong antibiotics and 17 having too short a therapeutic course of appropriate antibiotics. In 13, therapy was delayed for more than 48 hours after the onset of fever. Twenty-three patients did not receive antibiotic therapy at all despite bacteremia. A group of 95 inappropriately treated bacteremias was compared to 190 appropriately treated bacteremias occurring in the same period. Microbiological cure after the initial course of therapy was achieved more often (76.8% vs 38.9%, P < .001) in the group of appropriately treated bacteremias in all cases and also in the subgroup of leukemic patients (P < .01). Overall and attributable mortality were significantly lower in patients who were treated appropriately. There was no difference in the number of antibiotics administered in appropriately versus inappropriately treated bacteremias. Cost of therapy between both groups was similar., Conclusions: Inappropriately treated bacteremic cancer patients had outcomes that were significantly worse than patients who were treated appropriately. The reasons for inappropriate therapy were selection of the wrong antimicrobials, too short a duration of therapy, delayed onset of therapy, or absence of antimicrobial therapy.

One hundred and eighteen (118) episodes of bacteremia and fungemia in children with cancer were compared to 401 episodes of bacteremia and fungemia in adults with cancer to assess differences in etiology, risk factors and outcome. A retrospective univariate analysis was performed of all episodes of bacteremia in national pediatric and adult cancer institutions appearing in 1990-1996. A total of 519 episodes of bacteremia were assessed and compared. Both cancer centers differed in prophylactic antibiotic policies. About 50% of adults but less than 5% of children received quinolone prophylaxis during neutropenia, even though the empiric antibiotic therapeutic strategy was similar. There were differences in etiology between the groups: staphylococci and Stenotrophomonas maltophilia were more frequently observed in children (P<0.01), Pseudomonas aeruginosa and Acinetobacter spp. in adults (P<0.05). Gram-positive bacteremia was surprisingly more commonly observed in adults (65.7% vs 33.3%, P<0.01). Mixed polymicrobial bacteremia occurred more commonly in adults (31.8% vs 7.6%, P<0.001) than in children. Analysis of risk factors did not observe differences in risk factors except for underlying disease (acute leukemia was more frequently observed in children -48.3% vs adults 33.7%, P<0.05 and prophylaxis: (prior prophylaxis with quinolones was more common in adults (47.5%) than in children (2.5%) P<0.0001). Overall and attributable mortality in pediatric bacteremia was significantly lower than in adults (P<0.03).

A total of 262 bacteremic episodes were observed in cancer patients in a single cancer institution during the last 7 years, and the recorded outcome was death in 65. The 65 patients who died (24.8% overall mortality) were divided retrospectively into two subgroups: (a) those who died of underlying disease with bacteremia (45 cases, 16.9% crude mortality) and (b) those who died of bacteremia (20 patients, 7.7% attributable mortality). Comparison of several risk factors in subgroups of patients who achieved a cure (197 cases) and of those who died and whose deaths were attributable (20 cases) revealed six risk factors that were associated with attributable mortality: (1) chemotherapy-induced neutropenia (P < 0.03), (2) Acinetobacter/Stenotrophomonas spp. bacteremias (P < 0.001), (3) liver failure (P < 0.001), (4) inappropriate therapy (P < 0.0001), (5) organ complications (P < 0.003) and (6) multiresistant organisms (P < 0.001). Enterococci and Pseudomonas aeruginosa, surprisingly, were found more frequently in those who died of an underlying disease with bacteremia than among patients who were cured (17.6% vs 7.6%, P < 0.05 and 29.1% vs 13.8%, P < 0.02). Those who died of infection had higher numbers of positive blood cultures, with 2.05 per episode, than did those who died of underlying disease with bacteremia (1.82) or those who were cured (1.51). Other risk factors, such as underlying disease, type of chemotherapy, origin of bacteremia, age, and catheters did not predict either overall or attributable mortality within the study group.

Forty-one episodes of breakthrough fungaemia occurring over a 7.5 year period in the National and St Elizabeth's Cancer Institutes in Bratislava, Slovakia, were analysed. Five of them occurred during prophylaxis with fluconazole (one Torulopsis glabrata, one Hansenula anomala, two Candida krusei and one Candida parapsilosis), ten with itraconazole (three Trichosporon pullulans, one Trichosporon beigelii, one Cryptococcus laurentii, three Candida albicans and two T. glabrata), 11 during prophylaxis with ketoconazole (one Candida norvegenesis, one C. parapsilosis, one C. krusei, one Candida tropicalis, five C. albicans, one Candida stellatoidea and one C. laurentii and 15 during empirical therapy with amphotericin B (ten C. albicans, two T. beigelii and three Candida lusitaniae). The most frequent risk factors for breakthrough fungaemia were neutropenia, previous therapy with multiple antibiotics and recent catheter insertion. Comparing these episodes with 38 non-breakthrough fungaemias (appearing at the same institute in the same period) differences in certain risk factors were noted: breakthrough fungaemias were more frequently observed in patients with acute leukaemia (39.0% vs 5.2%, P < 0.001), mucositis (34.2% vs 13.1%, P < 0.05), prophylaxis with quinolones (58.5% vs 15.8%, P < 0.0001) and catheter-associated infections (29.3% vs 2.6%, P < 0.003). In this subgroup overall mortality (36.6% vs 28.8%) or early attributable mortality (22.0% vs 23.6%) were not significantly different.

The purpose of this study was to determine if patients with high vancomycin (VAN) serum levels experience more toxicity than underdosed patients with lower (VAN) levels, and whether low VAN serum levels cause therapeutic failures in patients with gram-positive bacteremia. In 198 cancer patients trough and peak serum levels of VAN were measured. Acute toxicity (Red Man syndrome) appeared in 3 patients (1.5%). Patients previously or currently treated with other nephrotoxic compounds (134 patients) presented the same incidence of nephrotoxicity as those receiving VAN for the first time in monotherapy (64 patients). VAN did not increase the toxicity when patients were dosed simultaneously or previously with aminoglycosides or amphotericin B. Our second observation, when studying serum levels in our 198 patients was that high VAN trough serum levels (trough > 15 microg/mL) were associated with significantly more nephrotoxicity (33.3% vs. 11.1%, P < 0.03) than low levels in the subgroups of either pretreated patients or unpretreated with other nephrotoxic drugs. None of 198 patients who had trough levels below 15 microg/mL had peak levels exceeding 40 microg/mL. This suggests that only serum monitoring of trough levels may predict nephrotoxicity. A case control study was conducted to compare a group of 22 VAN failures with 22 successfully treated patients matched in underlying disease and neutropenia who were treated in the same period, under the same antibiotic policy, at the same cancer center, for gram-positive bacteremia. Persisting, enterococcal, or mixed enterococcal plus staphylococcal bacteremia were the only statistically significant risk factors which predicted therapy failure in cancer patients. Neither peak nor trough VAN serum levels predicted failure or cure of gram-positive bacteremia in cancer patients.

From 1989 until 1996, during the last 8 years, the proportion of Candida (C.) krusei, and other non-albicans Candida spp. isolated from surveillance cultures and from sterile body sites, was analyzed among 13,758 admissions in a National Cancer Institute. During these admissions a total of 9,042 isolates were prospectively collected from surveillance cultures, and 126 from blood cultures. The proportion of C. krusei among all organisms was 12.7% to 16.5% in 1989 through 1991, i.e., before fluconazole was introduced into prophylactic protocols. After the introduction of fluconazole into prophylaxis in acute leukemia in 1992 the incidence of C. krusei was 7.9% to 8.6% during 1994 to 1996. After 5 years of using this drug for prophylaxis, the incidence of C. krusei was lower than before this drug was introduced in our institute. Among yeasts, the most frequently isolated pathogen was still Candida albicans (72.2% of all isolated fungal organisms). Among molds, Aspergillus spp. was the most frequently isolated agent. Analyzing the etiology of proven fungal infections (fungemias) confirmed by positive blood cultures, C. albicans was the most common causative organism in 53.8% of cases. The incidence of fungemia due to Torulopsis (C.) glabrata and C. krusei before and after fluconazole introduction did not change. Of 126 organisms isolated from blood cultures, there was no increase in T. (C.) glabrata or C. krusei after introduction of fluconazole for prophylaxis and therapy, and the quoted 6.4% of fungemic episodes remained stable with an incidence of 1 fungemia/year since 1991. The proportion of C. krusei and C. glabrata among Candida spp. was decreasing in our center between 1989 and 1996. Also, the proportion of non-albicans Candida spp. among isolates decreased from 25.7% in 1990 to 11.9% in 1996.

Relationships between aetiology, various risk factors (such as neutropenia, catheter insertion, endoscopy, therapy with corticosteroids, therapeutic use of antimicrobials, antibiotic prophylaxis, source of infection), symptomatology and outcome were studied in 553 monomicrobial bacteraemic episodes in cancer patients observed within 7 years at the National Cancer Institute of the Slovak Republic. The ratio of gram-positive to gram-negative bacteraemia was 1:1 (43.5% vs 43.8%), and yeasts caused 7.2% of monomicrobial episodes. The highest mortality was associated with Pseudomonas aeruginosa (19.2%), non-albicans Candida yeasts (25%) and Bacteroides fragilis (22.6%). Independent risk factors for particular pathogens were investigated by a computerized logistic regression model. The only independent risk factor for staphylococcal and enterococcal bacteraemia was vascular catheter insertion (OR = 1.95 and 2.05, CI = 95%, P = 0.035 and 0.044, respectively). However, there were no independent specific risk significant factors for viridans streptococcal bacteraemia and bacteraemia due to Enterobacteriaceae or Ps. aeruginosa. Neutropenia was found to be an independent predictor for development of Acinetobacter spp. bacteraemia (OR = 3.84, CI = 95%, P = 0.044). Prior therapy with third-generation cephalosporines was a predictive, independent risk factor for the development of fungaemia (OR = 1.99, CI = 95%, P = 0.028) but not of enterococcal bacteraemia. We also did not observe any association between prior therapy with imipenem and Stenotrophomonas maltophilia bacteraemias. Multivariate analysis confirmed that fungaemia may be independently associated with higher mortality than bacteraemia caused by Enterobacteriaceae and staphylococci. However, the mortality of fungaemia was statistically no different from that of Ps. aeruginosa, Stenotrophomonas spp. and viridans streptococci bacteraemias.

The resistance pattern of 2816 isolates from 17631 blood cultures and the etiology of isolates causing bacteremia and fungemia among 14591 admissions were investigated in an 80-bed single cancer institute during seven years (1990-1996) under the same empiric therapeutic antibiotic policy but with different prophylactic strategies. No change was found in the proportion of Gram-positive versus Gram-negative bacteria isolated from bacteremias (70% vs. 30%) during the past seven years. Furthermore, the proportion of coagulase-negative staphylococci and enterococci was about the same before and after the introduction of ofloxacin in prophylaxis. However, the proportion of Pseudomonas aeruginosa and Stenotrophomonas maltophilia causing bacteremia increased. There was no increase in Candida krusei and Candida glabrata after the introduction of fluconazole into our prophylactic regimen in 1992. Penicillin-resistance in viridans streptococci increased after penicillin was introduced into prophylaxis in acute leukemia in 1993. Until 1995 no quinolone-resistant Enterobacteriaceae were observed. Susceptibility to quinolones did not significantly change within the past seven years in Enterobacteriaceae after their introduction to prophylaxis in 1991, but Pseudomonas aeruginosa decreased from 90 to 58.2%. Glycopeptide resistance in enterococci and staphylococci was minimal in the observed period (0.9-4.3%).

60 patients with 60 viridans streptococcal bacteraemic episodes (42 due to penicillin-sensitive and 18 due to penicillin-resistant viridans streptococci) were analysed in a population of 12,185 admissions and 1,380 bacteraemic episodes during a 7-year period in a National Cancer Institute. The incidence of viridans streptococci among bacteraemias decreased from 11.5% in 1989 to 2.5% in 1995 after penicillin was introduced for prophylaxis of febrile neutropenia in acute leukaemia in 1993. However, the proportion of penicillin-resistant viridans streptococcal bacteraemias increased from 0 in 1989 and 1990 before any prophylaxis was given, to 12.9-16.7% after quinolones were used for prophylaxis in 1991 and 1992, and to 44.4-81.8% in 1993-1995 after penicillin was added to the quinolones. Mortality rate was higher in the subgroup of penicillin-resistant viridans streptococcal bacteraemias (p < 0.05). Statistically significant risk factors in patients with penicillin-resistant (compared with penicillin-sensitive) viridans streptococcal bacteraemia were: acute leukaemia (p < 0.03), high doses of cytarabine (p < 0.05), mucocutaneous lesions (p < 0.004), breakthrough bacteraemia during prophylaxis with ofloxacine plus penicillin (p < 0.001). Multiple logistic regression analysis showed that only acute leukaemia (OR 2.05, CI 0.85-1.85, p < 0.00452) and penicillin-resistance (OR 0.71, CI 0.103-4.887, p < 0.0209) were significant independent predictors of inferior outcome. Breakthrough bacteraemia during empiric therapy with vancomycine occurred in 5 of 116 patients treated with vancomycine, and during therapy with ampicillin plus gentamicin in 6 patients of 18 treated.

A total of 134 episodes of staphylococcal bacteremia (SBE) appearing among 9987 admissions, and 979 episodes of bacteremia in cancer patients within 5 years, were analyzed for risk factors, clinical course and outcome; 64 were monomicrobial and 70 polymicrobial. The most frequent risk factors were acute leukemia, catheter insertion, long-lasting neutropenia, and prior prophylaxis with quinolones. There was no significant difference between polymicrobial and monomicrobial SBE in risk factors. The two groups differed only in the source of bacteremia (gastrointestinal and respiratory-tract infections were more common in monomicrobial SBE) and etiology-Staphylococcus aureus appeared more frequently in monomicrobial than in polymicrobial bacteremia (20.3% compared to 4.3%, P < 0.05). More complications (14.3%) such as abscesses, endocarditis, etc. appeared in the group of polymicrobial SBE (P < 0.05). No difference was observed in clinical course and outcome between monomicrobial and polymicrobial SBE. The incidence of SBE has increased since 1991, when quinolones were first used in prophylaxis in afebrile neutropenia at our center; however, the infection-associated mortality in monomicrobial SBE was low (4.3%).

Ninety-nine patients with 101 bacteraemic episodes due to Pseudomonas aeruginosa (PA) within 6 years were divided into two groups according to their resistance to imipenem; of these 91 episodes were due to imipenem-sensitive (ISPA) and 10 due to imipenem-resistant (IRPA) strains. Risk factors, clinical course and outcome were evaluated and compared in the two groups. Acute leukaemia, long-lasting neutropenia, previous therapy with amikacin, third-generation cephalosporins, imipenem and prophylaxis with quinolones were significantly more frequently associated with IRPA than with ISPA. Imipenem-resistant PA bactereamias were associated with a higher incidence of septic shock (40% vs 19.8%) p. 161 0.02) and death 33.3%) than were ISPA bacteraemias. Since 1992, when first IRPA appeared, the incidence of imipenem-resistance increased tenfold, and in 1994, up to 10% of the PA populations causing bloodstream infections in cancer patients in our centre were imipenem-resistant.