Resistance Pattern of 2 816 Isolates Isolated from 17 631 Blood Cultures and Etiology of Bacteremia and Fungemia in a Single Cancer Institution

The resistance pattern of 2 816 isolates from 17 631 blood cultures and the etiology of isolates causing bacteremia and fungemia among 14 591 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%).     

Bacteremia Due to Multiresistant Gram-Negative Bacilli in Neutropenic Cancer Patients: A Case Controlled Study

Abstract

The aim of this study was to see if multiresistant Gram-negative bacteremias (MRGNB) are associated with specific risk factors and/or higher mortality in comparison to sensitive GNB (SGNB). Both groups, 51 patients and 102 controls, were matched for sex, age, underlying disease and neutropenia. In addition there were no significant differences in the incidence of cytotoxic chemotherapy administered, vascular catheter insertion and catheter as source of bacteremia and etiology of bacteremia. The proportion of Klebsiella-Enterobacter, Pseudomonas aeruginosa, Acinetobacter spp. and Steno-trophomonas maltophilia was similar in both groups. Prior surgery (21.6% vs 7.6%, p<0.02) was significantly associated with SGNB. Previous prophylaxis with quinolones (45.1% vs 24.5%, p<0.045), and prior therapy with broad spectrum antibiotics (41.2% vs 27.5%, p<0.05) were significantly more frequently observed among patients than controls. Patients with bacteremia due to MRGNB were also significantly more frequently infected with resistant bacteria. Attributable mortality was similar (15.7% vs 13.75%, NS) in both groups, however cure rates were lower among MRGNB patients. Crude mortality was higher among patients (35.3% vs 13.75%, p<0.01) in comparison to controls. In conclusion, prior antimicrobial prophylaxis and therapy with several classes of antimicrobials represents a significant risk for development of resistance. Mortality due to multiresistant Gram-negative bacteremias was higher in comparison to bacteremias due to susceptible organisms.     

Bacteremia and Fungemia in Pediatric Versus Adult Cancer Patients after Chemotherapy: Comparison of Etiology,Risk Factors and Outcome

Abstract

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).     

Characteristics of, and risk factors for, infections in patients with cancer treated with dasatinib and a brief review of other complications

Dasatinib has transformed the treatment of chronic myelogenous leukemia, resulting in durable remissions and prolonged survival. The spectrum of infectious complications during and after dasatinib therapy is not known. Retrospective analysis of records among 69 patients treated with dasatinib showed that 35 (51%) developed 57 episodes of infection. Twenty-nine (51%) episodes occurred during neutropenia, and 25 (44%) were microbiologically confirmed. Compared with patients who did not develop infection with dasatinib therapy, patients with infection were significantly more likely to have acute lymphocytic leukemia (51% vs. 18%; p ≤ 0.005) and to have received high-dose corticosteroids (51% vs. 26%; p ≤ 0.05). Patients with infection were also more likely to have received dasatinib with another antineoplastic agent (57% vs. 35% without infection; p = 0.09). On multivariate analysis, treatment with three or more cycles of dasatinib increased the risk of infection (odds ratio 11.7; 95% confidence interval 2.5-54.3; p = 0.002). The presence of comorbidities tended to increase the risk of infection (odds ratio 3.9; 95% confidence interval 0.9-17.9; p = 0.07). Interestingly, viral infections, including a single case of cytomegalovirus colitis, were uncommon (7%). The rate of death in 57 patients during follow-up was non-significantly higher in patients with infection versus those without infection (35% vs. 18%; p = 0.18). Infection-associated deaths were noted in only two patients (10%) who had an infection and died. The results of our analysis suggest that antibacterial prophylaxis is important in patients who develop neutropenia during dasatinib therapy, although routine antifungal and anti-cytomegalovirus prophylaxis may not be necessary.     

Efficacy of oral prophylactic antibiotics in neutropenic afebrile oncology patients: a systematic review of randomised controlled trials

The use of oral prophylactic antibiotics in oncology patients is still a matter of debate. A systematic review was performed to assess the evidence for the effectiveness of oral prophylactic antibiotics to decrease bacteraemia and infection-related mortality in oncology patients during neutropenic episodes. Medline, Embase and the Cochrane register of controlled trials were searched from 1966 until 2002. The main outcome was the number of patients with documented bacteraemia (Gram-negative or Gram-positive bacteraemia) and infection related mortality. Data-extraction and quality assessment were performed independently by two reviewers. A total of 22 trials met the inclusion criteria. Seventeen trials compared prophylaxis (quinolones or Trimethoprim/sulfamethoxazole (TMP/SMZ)) to no prophylaxis. The incidence of Gram-negative bacteraemia decreased significantly (pooled OR 0.39, 95% CI 0.24-0.62) without an increase in Gram-positive bacteraemia. Quinolone-based regimens showed a stronger reduction in Gram-negative bacteraemia while TMP/SMZ based regimens were more effective in Gram-positive bacteraemia. Infection related mortality due to bacterial causes decreased with the use of prophylactic antibiotics (pooled OR 0.49, 95% CI 0.27-0.88). No increase in fungaemia or fungal related mortality was seen with the use of oral prophylaxis. In conclusion, this study has shown that oral prophylactic antibiotics decreased Gram-negative bacteraemia and infection related mortality due to bacterial causes during neutropenic episodes in oncology patients.     

Ciprofloxacin prophylaxis in patients with acute leukemia and granulocytopenia in an area with a high prevalence of ciprofloxacin-resistant Escherichia coli

BACKGROUND: Infection remains the major cause of morbidity and mortality in patients with neutropenia, and the beneficial effects of oral prophylaxis remain controversial. METHODS: From 1993 to December 1999, the authors analyzed the clinical and microbiologic outcomes of 144 episodes of febrile neutropenia among adult patients with acute leukemia. RESULTS: Forty-three consecutive episodes occurred among patients who were on ciprofloxacin prophylaxis during 1993-1996 (ciprofloxacin group), and 101 subsequent episodes occurred among patients who were not exposed to ciprofloxacin prophylaxis (control group). There were no differences in clinical presentation, antibiotic treatment received for the episode, or a worse outcome between groups. The rate of bacteremia was similar (12 of 43 patients [28%] vs. 26 of 101 patients [26%], respectively). There was a trend toward a higher rate of Gram positive bacteremia in the control group (12 of 101 patients [12%] vs. 2 of 43 patients [5%]) and a higher rate of Gram negative bacteremia in the ciprofloxacin group (11 of 43 patients [26%] vs. 15 of 101 patients [15%]). Resistance to fluoroquinolones was greater in Escherichia coli blood isolates from patients in the ciprofloxacin group (7 of 8 patients vs. 2 of 9 patients; P = 0.02). CONCLUSIONS: The current results suggest that fluoroquinolone prophylaxis for patients with febrile neutropenia may be abandoned safely in areas with a high prevalence of ciprofloxacin-resistant enterobacteria.     

Bacteremia and Fungemia Occurring during Antimicrobial Prophylaxis with Ofloxacin in Cancer Patients: Risk Factors,Etiology and Outcome

Abstract

The authors analyzed 27 breakthrough bacteremias occurring during ofloxacin prophylaxis in afebrile neutropenia over 7 years in 9989 admissions and 979 bacteremic and fungemic episodes in a National Cancer Center in Bratislava, Slovak Republic. The most frequently isolated organisms in breakthrough bacteremias were gram-positive (71.3%), mainly coagulase-negative staphylococci (41.3%), enterococci (9.2%) and Corynebacteria (9.2%), followed by gram-negative rods - Pseudomonas aeruginosa (13.2%) and Stenotrophomonas maltophilia (9.2%). The outcome of breakthrough bacteremias during ofloxacin prophylaxis was not associated with the underlying disease, neutropenia, catheter insertion or resistance, but only with multiple risk factors. A higher failure rate was observed in those patients having a catheter infected with a resistant organism and during neutropenia. No patients with Hickman catheter were included in the study. Patients with mixed breakthrough bacteremia due to gram-negative and gram-positive organisms had higher failure rates than those with monomicrobial bacteremia. Catheter extraction and rapid institution of intravenous antibiotics in combination should be administered in breakthrough bacteremia.     

Salmonella enterica Serotype typhi in Kuwait and its reduced susceptibility to ciprofloxacin

Salmonella enterica serotype typhi continues to be an important public health problem in Kuwait. Analysis of the isolates from 163 patients, collected between 1995 and 2003, showed that the majority were from patients from the Indian sub-continent, including 45 from Bangladesh, 38 from India and 30 from Pakistan. Fifty-four of the strains showed multiple antibiotic resistance (MDR). Twenty-five strains were from Kuwaitis, with 15 aged <18 years. Bacteriophage typing of 20 isolates from Kuwaitis revealed that they belonged to 8 different phage types, and that the 3 MDR strains were phage type E1. Random amplified polymorphic DNA typing showed genetic variability amongst isolates from Kuwaiti patients. This method conveniently demonstrated the identity of 4 isolates associated with a small outbreak. 48 isolates from 2002-3 were tested for reduced susceptibility to quinolones. 12 of 18 MDR strains and 7/30 susceptible strains showed reduced susceptibility to ciprofloxacin (minimum inhibitory concentration 0.125-0.5 mg/L). All 12 strains were tested for mutation in the quinolone resistance determining region (QRDR) of the gyr A gene. The mutation ser83 phe was detected in the 10 strains tested. Thus typhoid fever in Kuwait is predominantly associated with those who have traveled from endemic areas to work in Kuwait. The incidence of MDR strains remains at about 30%. Reduced susceptibility to ciprofloxacin in MDR S. typhi has increased from (11%) in 1995-1996 to (67%) in 2002-2003 and from (0%) to (23%) in susceptible strains. Mutation of the gyrA gene is the mechanism most often responsible.     

Bacteremia due to Pseudomonas aeruginosa: results from a 3-year national study in the Slovak Republic

Risk factors, mortality and antimicrobial susceptibility of Pseudomonas aeruginosa bacteremias isolated from 148 patients from all University Hospitals in Slovakia were analyzed. Only 1.2% of 169 strains of P. aeruginosa were resistant to meropenem, 4.1% to piperacillin/tazobactam, 7.7% to ceftazidime as well as cefepime and 12% to amikacin. More than 30% of P. aeruginosa were resistant to ciprofloxacin. Our analysis of risk factors for antimicrobial resistance to the particular antimicrobials, indicated no difference in risk factors and outcome in cases infected with P. aeruginosa bacteremias resistant to amikacin, piperacillin/tazobactam or ceftazidime in comparison to episodes caused by P. aeruginosa due to susceptible isolates. When comparing risk factors for P. aeruginosa bacteremia in children vs. adults, cancer vs. non-cancer patients, several differences in risk factors were observed. Neither antimicrobial resistance to amikacin, ceftazidime or piperacillin/tazobactam, nor appropriateness of therapy according to two separate analyses were associated with better outcome.     

Effect of Deguelin on UVB-Induced Skin Carcinogenesis

Abstract

Salmonella enterica serotype typhicontinues to be an important public health problem in Kuwait. Analysis of the isolates from 163 patients, collected between 1995 and 2003, showed that the majority were from patients from the Indian sub-continent, including 45 from Bangladesh, 38 from India and 30 from Pakistan. Fifty-four of the strains showed multiple antibiotic resistance (MDR). Twenty-five strains were from Kuwaitis, with 15 aged <18 years. Bacteriophage typing of 20 isolates from Kuwaitis revealed that they belonged to 8 different phage types, and that the 3 MDR strains were phage type E1. Random amplified polymorphic DNA typing showed genetic variability amongst isolates from Kuwaiti patients. This method conveniently demonstrated the identity of 4 isolates associated with a small outbreak. 48 isolates from 2002-3 were tested for reduced susceptibility to quinolones. 12 of 18 MDR strains and 7/30 susceptible strains showed reduced susceptibility to ciprofloxacin (minimum inhibitory concentration 0.125-0.5 mg/L). All 12 strains were tested for mutation in the quinolone resistance determining region (QRDR) of the gyrA gene. The mutation ser83phe was detected in the 10 strains tested. Thus typhoid fever in Kuwait is predominantly associated with those who have traveled from endemic areas to work in Kuwait. The incidence of MDR strains remains at about 30%. Reduced susceptibility to ciprofloxacin in MDR S. typhi has increased from (11%) in 1995-1996 to (67%) in 2002-2003 and from (0%) to (23%) in susceptible strains. Mutation of the gyrA gene is the mechanism most often responsible.     

Reappraisal with meta-analysis of the addition of Gram-positive prophylaxis to fluoroquinolone in neutropenic patients.

PURPOSE: Past reports and meta-analyses indicate that fluoroquinolones are highly effective in preventing Gram-negative infections in neutropenic cancer patients, but offer inadequate coverage for Gram-positive infections. We evaluated by meta-analysis the efficacy of the addition of antimicrobial agents with enhanced Gram-positive activity to prophylaxis with quinolones.Materials and METHODS: Randomized trials comparing fluoroquinolones alone (ciprofloxacin, ofloxacin, pefloxacin, or norfloxacin) with fluoroquinolone in combination with Gram-positive prophylaxis (rifampin, vancomycin, amoxicillin, roxithromycin, or penicillin) were retrieved. We pooled relative risks (RRs) using a fixed-effects model. RESULTS: Nine trials (1,202 patients) published between 1993 and 2000 meet inclusion criteria. Compared with fluoroquinolone alone, Gram-positive prophylaxis reduced total bacteremic episodes (RR, 1.54; 95% CI, 1.26 to 1.88), streptococcal infections (RR, 2.20; 95% CI, 1.44 to 3.37), coagulase-negative staphylococcal infections (RR, 1.46; 95% CI, 1.04 to 2.04), and rate of febrile patients (RR 1.08; 95% CI, 1.00 to 1.16). Occurrence of clinically documented infections, unexplained fever, and infectious mortality was similar in the two groups. The addition of Gram-positive prophylaxis, however, significantly increased side effects (RR, 0.46; 95% CI, 0.28 to 0.76). Rifampin use resulted in a higher incidence of undesirable effects. CONCLUSION: Considering the lack of cut-clear benefit on some parameters of morbidity and mortality, routine use of Gram-positive prophylaxis is not advisable. This strategy, however, should be particularly valuable in subgroups of patients at high risk of streptococcal infection (eg, those with severe and prolonged neutropenia or mucositis, and those receiving cytarabine). Problems of tolerability and the potential for the emergence of resistant microorganisms should be considered when prescribing prophylaxis with enhanced Gram-positive activity to neutropenic patients.     

Bacteremia Due to Pseudomonas aeruginosa: Results from a 3-Year National Study in the Slovak Republic

Abstract

Risk factors, mortality and antimicrobial susceptibility of Pseudomonas aeruginosa bacteremias isolated from 148 patients from all University Hospitals in Slovakia were analyzed. Only 1.2% of 169 strains of P. aeruginosa were resistant to meropenem, 4.1% to piperacillin/tazobactam, 7.7% to ceftazidime as well as cefepime and 12% to amikacin. More than 30% of P. aeruginosa were resistant to ciprofloxacin.

Our analysis of risk factors for antimicrobial resistance to the particular antimicrobials, indicated no difference in risk factors and outcome in cases infected with P. aeruginosa bacteremias resistant to amikacin, piperacillin/tazobactam or ceftazidime in comparison to episodes caused by P. aeruginosa due to susceptible isolates. When comparing risk factors for P. aeruginosa bacteremia in children vs. adults, cancer vs. non-cancer patients, several differences in risk factors were observed.

Neither antimicrobial resistance to amikacin, ceftazidime or piperacillin/tazobactam, nor appropriateness of therapy according to two separate analyses were associated with better outcome.     

Infection control in neutropenia induced by high-dose cytarabine chemotherapy

A high-dose cytarabine (Cylocide; Ara-C: HDAC) chemotherapy has been successfully used as a postremission consolidation therapy for acute myeloid leukemia (AML). Although this chemotherapy has been estimated to cause severe myelosuppression, there has been no report about infection risk relating to HDAC chemotherapy. The purpose of this retrospective study is to evaluate the infection risk in AML patients treated with HDAC (n = 18) compared to those treated with standard-dose Ara-C (SDAC, n = 18). The mean duration of severe neutropenia (neutrophils < 500/microl) in HDAC group and SDAC was 14.8 days and 10.4 days, respectively, indicating a significant prolongation in the HDAC group (p < 0.05). The frequency of febrile neutropenia in the HDAC group tended to increase compared to that in the SDAC group (p = 0.093). The average days of usage of quinolone antimicrobial prophylaxis and aminoglycoside antibiotic injection in febrile neutropenia in the HDAC group were significantly longer than those of the SDAC group (quinolone; p < 0.01, aminoglycoside; p < 0.05). The frequency of Streptococcus infection isolated from pharyngeal mucus in the HDAC group was significantly higher than that in the SDAC group (100% versus 75%; p < 0.05). These results suggest that HDAC chemotherapy increased the infection risk compared to SDAC, and especially patients who received HDAC need a further prevention plan against gram-positive bacteria.     

Antitumor quinolones with mammalian topoisomerase II mediated DNA cleavage activity.

Ninety quinolones were evaluated to determine whether their ability to induce mammalian topoisomerase II mediated DNA cleavage in vitro correlated with their antitumor activity in vivo. Ten quinolones generated linear DNA at a yield of more than 10% of substrate supercoiled DNA in the mammalian topoisomerase II mediated DNA cleavage assay. All of these compounds showed a significant increase in life span (greater than 20%) in the murine leukemia P388 model. These antitumor quinolones have closely related structures: two halogens at C-6 and C-8; and cyclopropyl at N-1 of quinolone skeleton. In contrast, many analogues of the above quinolones, as well as new quinolones used clinically as an antibacterial drug, did not induce the cleavable complex in vitro or show antitumor activity in vivo. These findings indicate that quinolone derivatives can be a promising new class of antitumor agent targeting mammalian topoisomerase II.     

Comparison of efficacy and safety of teicoplanin and vancomycin in children with antineoplastic therapy-associated febrile neutropenia and gram-positive bacteremia

To compare their efficacy and safety, teicoplanin and vancomycin were randomly administered to 32 children for 52 gram-positive bacteremias during malignancy-associated neutropenia (<1000/microl). Patients mainly suffered from hematological malignancies. Twenty-five episodes were treated with teicoplanin (10 mg x kg(-1) x d(-1)) and 21 with vancomycin (40 mg x kg(-1) x d(-1)) plus ceftazidime and netilmicin. Six episodes were treated with teicoplanin because of previous "red man" reaction to vancomycin. Staphylococci (12% Staphylococcus aureus) were isolated from 50 episodes and viridans streptococci from 2. Defervescence on 3rd-4th day occurred in 29/31 (93.5%) teicoplanin-treated and 18/21 (85.7%) vancomycin-treated episodes. All 12 teicoplanin-treated and 13/13 vancomycin-treated episodes with repeat blood cultures on 3rd-4th day showed microbiological response. Two teicoplanin-treated and 3 vancomycin-treated patients required antifungals. Mild renal insufficiency appeared in 5 vancomycin-treated patients that was corrected without drug discontinuation. While both glycopeptides exhibit equal clinical and microbiological efficacy, teicoplanin is less likely to induce allergic reactions or nephrotoxicity in children.     

Multiple-species candidemia in patients with cancer

BACKGROUND: Candidemia is a common cause of bloodstream infections in patients with cancer, with the majority of these infections being caused by a single Candida species. Studies of multiple-species candidemia (MSC) have rarely been reported. METHODS: The authors identified 33 patients with cancer who had candidemia (diagnosed between 1993 and 2000) caused by more than 1 Candida species. This group of 33 patients was compared with a control group of 66 patients with cancer who had C. albicans candidemia that arose soon before or soon after each case of MSC that was investigated in the current study. RESULTS: Patients with MSC, compared with control patients, were more likely to have leukemia (33% vs. 8%; P = 0.001), to have had prolonged neutropenia before the onset of their infection (mean +/- standard deviation, 10 +/- 17 days vs. 3 +/- 6 days; P = 0.02), and to have received chemotherapy within 1 month before their infection (42% vs. 18%; P = 0.01). Patients with MSC also had higher Acute Physiology and Chronic Health Evaluation II scores at the onset of infection (score > or = 16, 45% vs. 26%; P = 0.05) and were more likely to have received previous antifungal prophylaxis compared with patients who had candidemia caused by C. albicans (33% vs. 11%; P = 0.006). The response of C. albicans candidemia to single-agent antifungal therapy was significantly better than that of MSC (69% vs. 35% P = 0.004). CONCLUSIONS: In patients with cancer, MSC was more likely to occur as breakthrough candidemia, predominantly in those with leukemia and prolonged neutropenia, and was associated with suboptimal responses to single-agent antifungal therapy.     

Antibiotic prophylaxis in neutropenic patients: new evidence, practical decisions

New evidence shows that antibiotic prophylaxis in neutropenic patients reduces mortality, febrile episodes, and bacterial infections. For patients with acute leukemia or those who undergo bone marrow transplantation, prophylaxis with fluoroquinolones diminished the risk of death from any cause by 33% (95% confidence interval [95% CI], 2-54%). Thus, 55 patients who have acute leukemia or who undergo bone marrow transplantation must receive prophylaxis to prevent 1 death. In 4 studies that included patients with solid tumors or lymphoma, prophylaxis reduced the rate of death during the first month (relative risk, 0.51; 95% CI, 0.27-0.97), and 82 patients had to receive prophylaxis to prevent 1 death. The main argument brought against prophylaxis is the induction of resistance. Patients who received prophylaxis did not experience more infections caused by resistant strains than patients in the control group. The recent GIMEMA study was conducted in a population with a nearly 50% resistance to fluoroquinolones in all pathogens and 20% resistance in gram-negative isolates, thus indicating that prophylaxis should be offered in settings with similar or less resistance. Prophylaxis with fluoroquinolones was efficacious in reducing infections caused by gram-positive bacteria. Patients who are treated for acute leukemia should be offered prophylaxis with ciprofloxacin or levofloxacin. Prophylaxis to cover the expected period of neutropenia may be considered for the first cycle of treatment in patients with solid tumors or lymphoma who regularly receive regimens that cause severe neutropenia. Excessive local levels of resistance to fluoroquinolones or high local incidence of infections caused by Clostridium difficile and related to fluoroquinolones should prompt a reconsideration of this policy.     

Appropriateness of empiric gentamicin and vancomycin therapy for bacteremias in chronic dialysis outpatient units in the era of antibiotic resistance

Bacteremias in inpatient chronic HD units have been described, but there is little information on bacteremias in ambulatory HD units. To determine the frequency of bacteremia and pathogen distribution in ambulatory chronic HD units, we retrospectively reviewed our experience with 107 bacteremias in 5 chronic ambulatory HD units over a 3 year period. The object of the study was twofold. The first objective was to determine if bacteremias in ambulatory HD setting were substantially different in frequency or type than in the inpatient HD setting. Secondly, febrile patients suspected of having bacteremia in chronic HD patients are often empirically treated with vancomycin and gentamicin. Chronic HD patients require repeated and frequent venous access for HD. Bacteremias are common in chronic HD patients and may be primary or secondary and are often related to venous access site infections. The distributions of bacteremia pathogens in chronic HD patients are predominantly reflective of skin flora, i.e., staphylococci and to lesser extent aerobic Gram-negative bacilli. After S. aureus (MSRA/MSSA) and coagulase-negative staphylococcus (CoNS), enterococci are the next most important Gram-positive pathogens in bacteremic HD patients. Most strains of E. faecalis are sensitive to vancomycin and for practical purposes should be considered as vancomycin sensitive enterococci (VSE). In contrast, most strains of E. faecium are resistant to vancomycin and should be considered as vancomycin resistant enterococci (VRE). We retrospectively reviewed 107 patients on chronic ambulatory HD to determine the adequacy of empiric vancomycin and gentamicin prophylaxis. We found amikacin is preferred to gentamicin and that meropenem is an effective alternate substitution for gentamicin and vancomycin combination therapy.     

The bactericidal effect on Pseudomonas strains of adriamycin associated with quinolones

The in vitro antibacterial activity of quinolone compounds was assessed on strains of Pseudomonas aeruginosa isolated from clinical infections. The bactericidal effect of quinolones was high and their respective antibacterial properties with adriamycin remained unimpaired on strains both sensitive and resistant to betalactam and aminoglycoside antibiotics. The cytotoxic effect of the combination of adriamycin and quinolones was determined in cultured P388 leukemia cells: no interference with the cytotoxic activity of adriamycin was observed.     

Neutropenic fever and severe sepsis in adult acute myeloid leukemia (AML) patients receiving intensive chemotherapy: Causes and consequences.

The objective of this study was to evaluate etiology and consequences of neutropenic fever in AML patients. Two hundred and ninety neutropenic periods following chemotherapy in 84 AML patients were retrospectively evaluated. Neutropenic fever was found in 280 periods (97%). Severe sepsis developed in 35 occasions (13%) and 9 patients (11%) died due to severe sepsis. In 165 episodes with neutropenic fever (59%), the potential causative organism was found in blood cultures. Gram-negative bacteria were more commonly found in patients who developed severe sepsis (40% vs. 23%, p = 0.03). CRP after 2 - 3 days from start with fever was higher in patients with severe sepsis (190 mg/L vs. 96 mg/L, p < 0.001) but the rise in CRP rather coincided than preceded with the development of severe sepsis. Severe sepsis is associated with significant mortality in AML patients. Earlier methods than CRP are needed to predict development of severe sepsis.