A double-blind comparison of empirical oral and intravenous antibiotic therapy for low-risk febrile patients with neutropenia during cancer chemotherapy

Immunomodulatory and protective effects of moxifloxacin against Candida albicans-induced bronchopneumonia in mice injected with cyclophosphamide

In a previous study, moxifloxacin was shown to ameliorate immunosuppression and enhance cytokine production in several tissues, including the lungs of cyclophosphamide-injected mice. We examined here the effects of moxifloxacin on Candida albicans lung infection in cyclophosphamide-injected mice. Mice were injected on day 0 with 250 mg of cyclophosphamide/kg, and on days 1 to 4 they were given moxifloxacin at 22.5 mg/kg/day compared to controls given ceftazidime at 75 mg/kg/day or saline. On day 6, C. albicans (10 7 CFU/mouse) was inoculated intratracheally, and animals were observed for the development of bronchopneumonia, weight loss, mortality, the presence of C. albicans, and lung cytokine production. Histopathology on day 10 postinoculation revealed bronchopneumonia in 50, 67, and 0% of saline-, ceftazidime-, and moxifloxacin-treated mice, respectively (P < 0.05). The mortality rates were 28, 17, and 5%, respectively (P < 0.05), and weight loss occurred at 20, 32, and 0%, respectively (P < 0.05). By day 15, C. albicans was eliminated from all moxifloxacin-treated mice but was still isolated from lung homogenates of 50 to 60% of the saline- and ceftazidime-treated groups. Among the cytokines tested on days 0 to 15, we found an increased production of tumor necrosis factor alpha, KC (functional interleukin-8), and gamma interferon in the lungs of ceftazidime- and saline-treated controls compared to the moxifloxacin pretreatment that abolished their secretion. In conclusion, moxifloxacin protected cyclophosphamide-injected mice from C. albicans-induced lung infection and significantly reduced pneumonia, weight loss, and mortality despite the lack of direct antifungal activity. This is most likely due to an immunomodulating activity conferred by moxifloxacin, as shown in this model and in our previous studies. Its potential protective role should be studied in patients undergoing chemotherapy and immune suppression.

Infections in the neutropenic patient--new views of an old problem

Infection in the neutropenic patient has remained a major clinical challenge for over three decades. While diagnostic and therapeutic interventions have improved greatly during this period, increases in the number of patients with neutropenia, changes in the etiologic agents involved, and growing antibiotic resistance have continued to be problematic. The evolving etiology of infections in this patient population is reviewed by Dr. Donowitz. Presently accepted antibiotic regimens and practices are discussed, along with ongoing controversies. In Section II, Drs. Maki and Crnich discuss line-related infection, which is a major infectious source in the neutropenic. Defining true line-related bloodstream infection remains a challenge despite the fact that various methods to do so exist. Means of prevention of line related infection, diagnosis, and therapy are reviewed. Fungal infection continues to perplex the infectious disease clinician and hematologist/oncologist. Diagnosis is difficult, and many fungal infections will lead to increased mortality even with rapid diagnosis and therapy. In Section III, Dr. Pappas reviews the major fungal etiologies of infection in the neutropenic patient and the new anti-fungals that are available to treat them. Finally, Dr. Rolston reviews the possibility of outpatient management of neutropenic fever. Recognizing that neutropenics represent a heterogeneous group of patients, identification of who can be treated as an outpatient and with what antibiotics are discussed.

Empirical oral antibiotic therapy for low risk febrile cancer patients with neutropenia

For over 30 years, fever and neutropenia in cancer patients has been treated with the utmost urgency, necessitating inpatient evaluation and immediate initiation of empirical broad-spectrum parenteral (i.v.) antibiotics. This practice is based on the recognition that delays in starting antibiotic therapy in febrile neutropenic patients have been associated with life-threatening infections and sometimes fatal consequences. Over the past decade, it has become evident that neutropenic cancer patients are not a homogeneous group and that practice guidelines may vary on their risk status. In fact, attempts have been made to stratify patients into high-risk and low-risk groups and differentiate treatment options respectively. Recent studies suggest that those neutropenic cancer patients who are at low risk may even be successfully treated with oral therapy, thus opening the possibility for ambulatory or home-based management. Oral antibiotic therapy, especially if safely delivered at home, offers a number of advantages including lower cost, improved quality of life (although the impact of shifting the burden of care from the hospital to the home setting on the patient, parent or care provider needs careful assessment) and a decreased risk for nosocomial infection.

Value of electronic data for model validation and refinement: bacteremia risk in children with fever and neutropenia

BACKGROUND

Validating published risk models in a different time and setting can be a labor-intensive process. Data in electronic format provide the potential to test the validity of risk models without labor-intensive chart reviews and data capture. The authors attempted to use readily available electronic data to find appropriate cases and to validate and refine a previously developed risk model for predicting bacteremia in children with cancer who had fever and neutropenia.

PATIENTS AND METHODS

By applying a largely automated case-finding algorithm to linked, electronic clinical and administrative data systems, the authors identified and acquired data regarding 157 episodes of fever and neutropenia in children with cancer admitted to a children's hospital during an 11-month period in 1997. The authors applied a previously developed and validated risk model for bacteremia to this 1997 cohort by assessing the odds ratios among risk groups. The model assigns encounters with absolute monocyte count of 100 cells or more/mm3 to a low-risk group and encounters with an absolute monocyte count of less than 100 cells/mm3 to intermediate-risk (temperature <39.0 degrees C) or high-risk (> or = 39.0 degrees C) groups. In addition, the authors explored whether the new data would have generated the same model. Univariate and multivariable analyses were performed to determine whether there were additional independent predictors of bacteremia. Recursive partitioning of admission absolute monocyte count and temperature was used to assess whether similar cutpoints would be found.

RESULTS

There were 12 episodes of bacteremia (7.6%) among the 157 encounters. The previously developed model correctly predicted increasing rates of bacteremia in this 1997 cohort, ranging from 2.5% in the low-risk group (one episode in a child with an infected central line) to 24% in the high-risk group. The odds ratio for the high-risk versus intermediate-risk group was 4.09 (95% confidence interval 1.05-15.91), comparable to the odds ratio of 3.96 in the previously published derivation cohort (95% confidence interval 1.4-11.1). Multivariate analysis of the new data revealed no independent risk factors for bacteremia other than admission absolute monocyte count and temperature. Recursive partitioning of absolute monocyte count and temperature generated risk categories that were somewhat different from those of the original model. The new data yielded three categories: low risk (temperature < or = 39.5 degrees C and absolute monocyte count >10/mm3), intermediate risk (temperature < or = 39.5 degrees C and absolute monocyte count < or = 10/mm3), and high risk (temperature >39.5 degrees C).

CONCLUSIONS

Existing electronic data provide an efficient means for case-finding and model validation and refinement. The previously developed bacteremia model had good but not optimal predictive performance in the new data set. Admission absolute monocyte count and temperature remain significant risk factors for bacteremia. Redefining the risk categories, including a much lower cutpoint for admission absolute monocyte count, improved the model's discrimination, which suggests that predictive models need periodic updating.

Antibiotics and growth factors in the management of fever and neutropenia in cancer patients

The association of neutropenia and infection continues to be a major cause of morbidity and mortality in cancer patients receiving myelosuppressive chemotherapy. Prompt hospitalization and initiation of empirical intravenous broad-spectrum antibiotics has been the standard of care during the past three decades. Recently, risk-assessment models have been developed that allow the identification of febrile neutropenic patients that are at low risk for medical complications and mortality. New treatment strategies are being evaluated in this low-risk patient population to safely reduce toxicity, decrease costs, and improve quality of life. These include early shift from intravenous therapy to oral antibiotics, immediate initiation of oral empiric treatment, early hospital discharge, or outpatient care. A risk-based approach should also be applied to the use of colony-stimulating factors in this setting. Growth factors should not be routinely administered to neutropenic patients with uncomplicated febrile episodes. However, recent data support their use in populations with high-risk neutropenic fever.

Commonly used antibacterial and antifungal agents for hospitalised paediatric patients: implications for therapy with an emphasis on clinical pharmacokinetics

Due to normal growth and development, hospitalised paediatric patients with infection require unique consideration of immune function and drug disposition. Specifically, antibacterial and antifungal pharmacokinetics are influenced by volume of distribution, drug binding and elimination, which are a reflection of changing extracellular fluid volume, quantity and quality of plasma proteins, and renal and hepatic function. However, there is a paucity of data in paediatric patients addressing these issues and many empiric treatment practices are based on adult data. The penicillins and cephalosporins continue to be a mainstay of therapy because of their broad spectrum of activity, clinical efficacy and favourable tolerability profile. These antibacterials rapidly reach peak serum concentrations and readily diffuse into body tissues. Good penetration into the cerebrospinal fluid (CSF) has made the third-generation cephalosporins the agents of choice for the treatment of bacterial meningitis. These drugs are excreted primarily by the kidney. The carbapenems are broad-spectrum beta-lactam antibacterials which can potentially replace combination regimens. Vancomycin is a glycopeptide antibacterial with gram-positive activity useful for the treatment of resistant infections, or for those patients allergic to penicillins and cephalosporins. Volume of distribution is affected by age, gender, and bodyweight. It diffuses well across serous membranes and inflamed meninges. Vancomycin is excreted by the kidneys and is not removed by dialysis. The aminoglycosides continue to serve a useful role in the treatment of gram-negative, enterococcal and mycobacterial infections. Their volume of distribution approximates extracellular space. These drugs are also excreted renally and are removed by haemodialysis. Passage across the blood-brain barrier is poor, even in the face of meningeal inflammation. Low pH found in abscess conditions impairs function. Toxicity needs to be considered. Macrolide antibacterials are frequently used in the treatment of respiratory infections. Parenteral erythromycin can cause phlebitis, which limits its use. Parenteral azithromycin is better tolerated but paediatric pharmacokinetic data are lacking. Clindamycin is frequently used when anaerobic infections are suspected. Good oral absorption makes it a good choice for step-down therapy in intra-abdominal and skeletal infections. The use of quinolones in paediatrics has been restricted and most information available is in cystic fibrosis patients. High oral bioavailability is also important for step-down therapy. Amphotericin B has been the cornerstone of antifungal treatment in hospitalised patients. Its metabolism is poorly understood. The half-life increases with time and can be as long as 15 days after prolonged therapy. Oral absorption is poor. The azole antifungals are being used increasingly. Fluconazole is well tolerated, with high bioavailability and good penetration into the CSF. Itraconazole has greater activity against aspergillus, blastomycosis, histoplasmosis and sporotrichosis, although it's pharmacological and toxicity profiles are not as favourable.

Evaluation of risk prediction criteria for episodes of febrile neutropenia in children with cancer

PURPOSE

To evaluate the feasibility of risk stratification of children with cancer and febrile neutropenia using a simple set of criteria from data available to the clinician at the time of the patient's presentation.

PATIENTS AND METHODS

This study is a retrospective cohort study of all children with cancer admitted to a single institution with fever and neutropenia (defined as an absolute neutrophil count < 500 cells/mm3) in a 1-year period. Patients were defined a priori as low risk if they were outpatients at the time of presentation with febrile neutropenia, had an anticipated duration of neutropenia less than 7 days, and had no significant comorbidity. All others were considered high risk. Data was analyzed by first admission for each patient and secondarily for all admissions for febrile neutropenia.

RESULTS

There were 188 admissions in 104 patients for febrile neutropenia during the study period. Of these 47% were high risk and 53% were low risk. The duration of fever was not significantly different in the two groups. However, the duration of neutropenia and the length of hospital stay were significantly longer in the high-risk group. The frequency of bacteremia, other documented infection, and serious medical complications was significantly different in the two groups. Overall, the rate of any adverse event was 4% in the low-risk group versus 41% in the high-risk group.

CONCLUSIONS

Simple criteria available to the clinician at the time of evaluation of the child with cancer who has fever and neutropenia allow the selection of a population at low risk for bacteremia or serious medical complication. A prospective study is planned using these risk criteria, evaluating outpatient oral antibiotic therapy in low-risk children with cancer.

Infectious diseases in gynecologic oncology: an overview

The increasing trend of a multimodal therapeutic approach in gynecologic oncology in the last few years has markedly changed the nature, frequency, and clinical presentation of infectious diseases. Despite the improved diagnostic tools, refined surgical technique, and routine use of prophylactic antibiotics, the morbidity and mortality of infectious complications remain significant. The rational use of available treatment resources, the recognition of risk factors, and increased awareness of host-cancer interactions should reduce the incidence of these serious infectious complications. The improved prevention and more efficient treatment of infections in the gynecologic oncology patient will not only improve prognosis but also have a significant economic impact as well.

[Infection in patients with neutropenia that undergo an autologous peripheral blood stem cell transplant due to breast cancer]

BACKGROUND

The extent and duration of neutropenia and the characteristics of the underlying disease are determinant factors for the prognosis of febrile syndromes. Despite the fact that traditionally the peripheral blood stem cell transplantation (PBSCT) were considered to cause high risk neutropenia, in all probability the neutropenia observed in the PBSCT in some solid tumours could be considered moderate risk. Febrile episodes in patients with these characteristics were evaluated.

METHODS

We prospectively analysed 132 autologus PBSCT in patients with breast cancer (1994-1999). Conditioning regime: STAMP V. Antibacterial prophylaxis: ofloxacin (400 mg/12 hrs PO). Classification of the febrile syndrome: bacteremia, microbiologically documented infection withut bacteremia, clinical infection and a fever of unknown origin.

RESULTS

122 patients had a fever (92%), mean age: 45 years (range: 27-61). There were 32 (26%) bacteremias, 13 (11%) microbiologically documented infections without bacteremia and 54 (44%) clinical infections. The mean number of days with a neutrophil count of <1x109/1 was 14 (range: 11-20). In the 74 patients (61%) that had a granulocyte colony stimulating factor (G-CSF), the mean number of days to reach a 0,5x109/I neutrophil count (7,6) and the average number of days in hospital (26) were significantly less. There was a main infectious point in 80 patients (65%): the most frequent being oropharynx in 33 cases (46%) and digestive in 29 cases (41%). 48 gram negative (GN) 29 gram positive (GP) bacteria were isolated (71% of the GN's were resistant to ofloxacin). Between 1997-1999 the GN/GP ratio was 2,3. There were no deaths related to the infection.

CONCLUSIONS

Given the excellent evolution of our patients we can consider their neutropenia to be moderate or low risk, and they are a long way from the death rates caused by infections published by other types of hemopoietic transplants. The predominance of GN over the last few years and their limited sensitivity to quinolones means that their prophylactic use in these patients should be reconsidered.

Clinical parameters associated with low bacteremia risk in 1100 pediatric oncology patients with fever and neutropenia

BACKGROUND

Traditionally, children with malignant disease who present with fever and neutropenia are hospitalized for parenteral antibiotics. More recently, outpatient strategies have been proposed for lower risk cohorts of such patients. The authors sought to identify clinical and laboratory parameters that are associated with a low risk of bacteremia in children with malignant disease who presented with febrile neutropenia.

METHODS

A multicenter, retrospective cohort of children with malignant disease and fever with neutropenia was established in three pediatric oncology centers over a 5-year period. A total of 1171 episodes of febrile neutropenia (absolute neutrophil count [ANC] < 500 cells per mm(3)) were identified in children with malignant disease age > 1 year. The endpoints examined were 1) bacteremia and 2) intensive care unit admission or death related to bacteremia. The odds ratio was used to determine which of the following admission parameters and cut-off values were associated with the lowest risk for bacteremia: ANC, absolute phagocyte count (APC), absolute monocyte count (AMC), platelet count, and admission temperature.

RESULTS

A total of 189 episodes of bacteremia were identified among the 1171 episodes of febrile neutropenia (14% bacteremia). Only 11 of 1171 episodes (0.9%) resulted in intensive care unit admission, and 3 of these patients died. All 11 patients had an AMC < 30 cells per mm(3). The lowest frequency of bacteremia (6.1%) occurred in the children with an admission AMC of > or = 155 cells per mm(3). None of the patients identified as low risk by AMC required an intensive care unit admission or died. No level of ANC, APC, temperature, or platelet count was associated with a statistically significant decrease in the risk for bacteremia in the patient population.

CONCLUSIONS

Adverse outcomes due to bacteremia are infrequent in pediatric oncology patients who present with fever and neutropenia are treated with parental antibiotics. Patients with fever and neutropenia and an AMC value of > or = 155 cells per mm(3) have the lowest risk for bacteremia and may be potential candidates for outpatient management.

Risk assessment and risk-based therapeutic strategies in febrile neutropenia

Different approaches have developed over time regarding the empirical antimicrobial therapy of fever in neutropenic patients. The use of intravenous antibiotics remains the standard approach. Clinical criteria and 'low-risk' prediction rules have been developed that help select patients in whom oral therapy is well tolerated and who may be eligible for outpatient management. Comorbidity and clinical status at presentation remain important criteria in the risk-assessment process. Outpatient management requires additional assessment of non-medical criteria. Patients without documented infection and who have responded to initial therapy may benefit from simplified therapy such as a switch to oral drugs and/or outpatient management. Discontinuation of therapy may be considered in selected cases. Risk assessment in neutropenic patients with persistent unexplained fever is challenging. Available data suggest that broadening of the antibacterial coverage is of limited value. Instead, definition of the risk of fungal infection by using clinical criteria, imaging and laboratory studies, as well as the identification of those patients likely to benefit from antifungal therapy, appear to be of critical importance.

Prospective, multicenter evaluation of risk factors associated with invasive bacterial infection in children with cancer, neutropenia, and fever

PURPOSE

To identify clinical and laboratory parameters present at the time of a first evaluation that could help predict which children with cancer, fever, and neutropenia were at high risk or low risk for an invasive bacterial infection.

PATIENTS AND METHODS

Over a 17-month period, all children with cancer, fever, and neutropenia admitted to five hospitals in Santiago, Chile, were enrolled onto a prospective protocol. Associations between admission parameters and risk for invasive bacterial infection were assessed by univariate and logistic regression analyses.

RESULTS

A total of 447 febrile neutropenic episodes occurred in 257 children. Five parameters were statistically independent risk factors for an invasive bacterial infection. Ranked by order of significance, they were as follows: C-reactive protein levels of 90 mg/L or higher (relative risk [RR], 4.2; 95% confidence interval [CI], 3.6 to 4.8); presence of hypotension (RR, 2.7; 95% CI, 2.3 to 3.2); relapse of leukemia as cancer type (RR, 1.8, 95% CI, 1.7 to 2.3); platelet count less than or equal to 50,000/mm(3) (RR, 1.7; 95% CI, 1.4 to 2.2); and recent (< or = 7 days) chemotherapy (RR, 1.3; 95% CI, 1.1 to 1.6). Other previously postulated risk factors (magnitude of fever, monocyte count) were not independent risk factors in this study population.

CONCLUSION

In a large population of children, common clinical and laboratory admission parameters were identified that can help predict the risk for an invasive bacterial infection. These results encourage the possibility of a more selective management strategy for these children.

Infectious complications of febrile leukopenia

It can be foreseen that in the years to come major improvements in neutropenic host infections will be achieved regarding the exact identification of risk factors, allowing better patient stratification; the application of molecular techniques to recognize pathogens; the development of effective new oral antimicrobials allowing home therapy or abbreviated hospitalization; the development of new antifungals; and the development of new effective immunomodulators and cytokines to ameliorate chemotherapy-induced neutropenia. In the years to come the threat of nosocomial infections unfortunately will not be eliminated, while the development of major new parenteral antibiotics cannot be foreseen. It is therefore the caregiver/physician himself who, by applying rational antibiotic policies and strict handwashing rules, will probably escape, for his neutropenic patient's sake, the imminent threat of multiresistant pathogens.

Immunomodulatory effects of moxifloxacin in comparison to ciprofloxacin and G-CSF in a murine model of cyclophosphamide-induced leukopenia

We analyzed the effect of the two quinolones moxifloxacin and ciprofloxacin on the repopulation of hematopoietic organs and on the production of cytokines by various organs of cyclophosphamide (CP)-induced leukopenic mice. The effect was compared to that of G-CSF. Cyclophosphamide injection induced a severe leukopenia, with nadir at day 4 post-injection. All the quinolone and G-CSF-treated animals showed WBC>500/microL at the nadir, compared to 50% of saline-treated mice. Cyclophosphamide induced a marked decrease in the number of myeloid progenitors (CFU-C) in bone marrow (BM) and spleen. Quinolone or G-CSF treatment resulted in a 1.4-4.3-fold increase in CFU-C numbers in the BM; no enhancement was observed in the spleen. Treatment with CP resulted in enhanced colony-stimulating activity (CSA) in bone shaft and spleen and decreased activity in bladder and lung. Treatment of CP-injected mice with quinolones significantly enhanced CSA in the bone shaft, spleen, lung and bladder on different days. In normal mice the highest levels of GM-CSF and IL-6 were observed in lung-conditioned medium (compared to bone shaft, spleen and bladder). Injection of CP resulted in a 22.5- and 93-fold decrease in GM-CSF and IL-6 levels, respectively, in lung-conditioned medium, while treatment with quinolones resulted in 2-4-fold increase in GM-CSF with no effect on IL-6 production. G-CSF treatment had no enhancing effect on GM-CSF nor on IL-6 production. We conclude that moxifloxacin and ciprofloxacin administered to CP-injected mice revert some of the immune suppressive effects of cyclophosphamide.

Oral ciprofloxacin in the management of children with cancer with lower risk febrile neutropenia

BACKGROUND

Recent reports and a previous randomized trial conducted at the authors' institution suggested that a lower risk subset of children with febrile neutropenia under chemotherapy might benefit of an oral antibiotic outpatient approach.

METHODS

The objective of this study was to test the efficacy of oral ciprofloxacin in the treatment of lower risk febrile neutropenia (LRFN) in children treated for malignant diseases. From November 1998 to December 1999, 93 episodes of LRFN in 87 children (median age, 5.5 years; range, 0.9-15.8 years) were included in a prospective randomized controlled single institution trial. Inclusion criteria included fever (> 38 degrees C), severe neutropenia (absolute neutrophil count, < 500/mm(3)), and lower risk features (e.g., absence of severe comorbidity factors, good clinical condition, negative blood cultures, control of local infection, prediction of a period of neutropenia less than 10 days after admission, and compliant parents). After 24 hours of a single intravenous ceftriaxone (100 mg/kg) plus amikacin (15 mg/kg) and completed risk assessment workup, patients were discharged and randomly allocated to two groups. Group A (48 episodes) received ciprofloxacin 20 mg/kg/day orally (p.o.) every 12 hours for 6 days. Group B (45 episodes) received intravenous ceftriaxone plus amikacin for 2 days more followed by cefixime (8 mg/kg/day p.o.) every 24 hours for 4 additional days. Failure was defined as the need of a second hospitalization during the same episode.

RESULTS

Most of the patients (59% in Group A and 52% in Group B) were treated for malignant solid tumors. Fifteen (31%) children in Group A and 15 (33%) in Group B presented with fever of unknown origin (P value was not significant). No significant differences were found in sites of initial infection between both groups. Overall results in this study were excellent. Only one patient with respiratory failure was detected in Group B, who did well with secondary treatment.

CONCLUSIONS

In febrile neutropenic children after anticancer therapy and lower risk features, oral ciprofloxacin for 6 days after 24 hours of intravenous ceftraxione plus amikacin appears to be as efficacious as intravenous ceftriaxone plus amikacin for 2 days more followed by cefixime for 4 additional days. These results contribute to strengthen the concept of LRFN.

Management of fever in neutropenic patients

Substantial progress has been made in the management of febrile episodes in neutropenic patients, largely by the prompt administration of potent, broad-spectrum antimicrobial agents. During the past several decades, the spectrum of organisms has changed from a predominance of gram-negative pathogens to a predominance of gram-positive pathogens. In recent years, some hospitals have experienced an increase of infections caused by multi-drug-resistant pathogens. Hence, it is no longer possible to rely on standardized regimens, but antimicrobial therapy must be selected based on the predominant pathogens and antimicrobial susceptibility patterns at each institution. It is customary to initiate antifungal therapy empirically in those patients whose fever persists despite broad-spectrum antibacterial therapy. Alternatives now exist to amphotericin B, including lipid formulations of this drug, and fluconazole. It is critically important that each patient be carefully re-assessed before starting antifungal therapy, because there are many other potential causes for persistent fever, including resistant bacteria and viruses. Novel approaches to therapy include outpatient antibiotics, and use of growth factors as adjunctive therapy. There also has been a renewed interest in white blood cell transfusions. Although the prognosis for infection in neutropenic patients has improved greatly, new infectious problems have emerged that limit our successful management of these complications.

Randomized, double-blind, multicenter trial comparing clinafloxacin with imipenem as empirical monotherapy for febrile granulocytopenic patients

In a double-blind, multicenter trial, 541 febrile granulocytopenic patients were randomized to receive either intravenous (iv) clinafloxacin (200 mg every 12 h) or i.v. imipenem (500 mg every 6 h) as empirical monotherapy. More baseline pathogens were susceptible to clinafloxacin (259 [99%] of 262 organisms) than to imipenem (253 [95%] of 265; P=.03). Initial favorable clinical response rates for clinafloxacin (88 [32%] of 272 patients) and imipenem (89 [33%] of 269) were similar. After addition of other antimicrobial agents, overall response rates were 259 (95%) of 272 for clinafloxacin and 251 (93%) of 269 for imipenem. During the study, only 13 clinafloxacin (5%) and 18 imipenem (7%) recipients died. Both drugs were generally well tolerated. Drug-related skin rash occurred more often with clinafloxacin (11% vs. 6%; P=.07), whereas nausea (2% vs. 5%; P=.16), Clostridium-difficile-associated diarrhea (3% vs. 8%; P=.02), and seizures (0% vs. 2%; P=.06) occurred more often with imipenem. These results suggest that clinafloxacin and imipenem have similar efficacy as empirical monotherapy in febrile granulocytopenic patients.

Granulocyte colony-stimulating factor in the treatment of high-risk febrile neutropenia: a multicenter randomized trial

BACKGROUND

Granulocyte colony-stimulating factors (G-CSFs) have been shown to help prevent febrile neutropenia in certain subgroups of cancer patients undergoing chemotherapy, but their role in treating febrile neutropenia is controversial. The purpose of our study was to evaluate-in a prospective multicenter randomized clinical trial-the efficacy of adding G-CSF to broad-spectrum antibiotic treatment of patients with solid tumors and high-risk febrile neutropenia.

METHODS

A total of 210 patients with solid tumors treated with conventional-dose chemotherapy who presented with fever and grade IV neutropenia were considered to be eligible for the trial. They met at least one of the following high-risk criteria: profound neutropenia (absolute neutrophil count <100/mm(3)), short latency from previous chemotherapy cycle (<10 days), sepsis or clinically documented infection at presentation, severe comorbidity, performance status of 3-4 (Eastern Cooperative Oncology Group scale), or prior inpatient status. Eligible patients were randomly assigned to receive the antibiotics ceftazidime and amikacin, with or without G-CSF (5 microg/kg per day). The primary study end point was the duration of hospitalization. All P values were two-sided.

RESULTS

Patients randomly assigned to receive G-CSF had a significantly shorter duration of grade IV neutropenia (median, 2 days versus 3 days; P = 0.0004), antibiotic therapy (median, 5 days versus 6 days; P = 0.013), and hospital stay (median, 5 days versus 7 days; P = 0.015) than patients in the control arm. The incidence of serious medical complications not present at the initial clinical evaluation was 10% in the G-CSF group and 17% in the control group (P = 0.12), including five deaths in each study arm. The median cost of hospital stay and the median overall cost per patient admission were reduced by 17% (P = 0.01) and by 11% (P = 0.07), respectively, in the G-CSF arm compared with the control arm.

CONCLUSIONS

Adding G-CSF to antibiotic therapy shortens the duration of neutropenia, reduces the duration of antibiotic therapy and hospitalization, and decreases hospital costs in patients with high-risk febrile neutropenia.

Antipseudomonal antibiotics

Pseudomonas aeruginosa is responsible for a variety of nosocomial infections associated with high morbidity and mortality, involving the immunocompromised and immunocompetent host. There are several groups of antipseudomonal antibiotics available today: antipseudomonal penicillins (carboxy and ureido penicillins), antipseudomonal cephalosporins, monobactams, quinolones, aminoglycosides, and carbapenems. This article reviews the newer antipseudomonal compounds and focuses on recent and important pieces of information for older compounds. Antibacterial spectrum, with particular emphasis on contemporary resistance mechanisms, and recent global resistance surveillance reports, pharmacokinetics, in vitro combination studies and in vivo interactions, and adverse effects and dosage schedules are described in an effort to approach the clinicians' needs.

Oral cefixime is similar to continued intravenous antibiotics in the empirical treatment of febrile neutropenic children with cancer

Empiric oral antibiotic therapy for febrile neutropenic cancer patients has been suggested as a means to decrease hospitalization, but the safety of this approach has not been adequately studied in children. We compared continued iv antibiotic therapy with switching treatment to orally administered cefixime in a group of selected febrile neutropenic children for whom blood cultures were sterile after 48 h of incubation. Two hundred episodes of febrile neutropenia were studied (156 patients), and 100 episodes were randomized to receive each treatment. Failure to respond to therapy was defined by documented or suspected bacterial infection, recurrent fever, or discontinuation of assigned therapy for any reason before neutropenia resolved. Rates of treatment failure were similar in the oral cefixime group (28%) and in the iv antibiotic group (27%; P=1.0). Results support the safety of oral cefixime therapy for low-risk febrile neutropenic children, a therapeutic approach that would facilitate earlier outpatient management and decrease the costs of treatment.

Sequential antibiotic therapy

Antimicrobials are an important source of hospital expenditure. Traditionally, severe bacterial infections have been treated initially with intravenous antibiotics, followed by physician-directed switch to oral therapy. Unfortunately this approach results in unnecessary prolongation of intravenous treatment, with all its inherent disadvantages. Sequential antibiotic therapy, however, ensures an early switch to the oral route when the patient is clinically stable. This increasingly employed strategy is safe and results in improved quality and cost-effectiveness of health care. To ensure timely and appropriate switch, such programmes need to be underpinned by clear guidelines and supported by a multidisciplinary team. In the future, key questions, such as what is the optimal time of switch for specific infections, and can conditions such as osteomyelitis and endocarditis be efficaciously treated with oral therapy, need to be answered. Only then will clinicians be able to practise evidence-based infection management incorporating sequential antimicrobial therapy.

Monotherapy with intravenous followed by oral high-dose ciprofloxacin versus combination therapy with ceftazidime plus amikacin as initial empiric therapy for granulocytopenic patients with fever

The aim of the present study was to obtain clinical experience with the use of high-dose ciprofloxacin as monotherapy for the treatment of febrile neutropenia episodes (granulocyte count, <500/mm(3)) compared to a standard regimen and to clarify whether ciprofloxacin administration may be switched to the oral route. In a prospective randomized study ciprofloxacin was given at 400 mg three times a day (t.i.d.) for at least 72 h followed by oral administration at 750 mg twice a day (b.i.d). That regimen was compared with ceftazidime given intravenously at 2 g t.i.d. plus amikacin given intravenously at 500 mg b.i.d. The frequency of successful clinical response without modification at the end of therapy was almost identical for ciprofloxacin (50% [62 of 124 patients]) compared with that for ceftazidime plus amikacin (50.8% [62 of 122 patients]) in an intent-to-treat analysis; the frequencies were 48.3% (57 of 118 patients) versus 49.6% (56 of 113 patients), respectively, in a per-protocol analysis (P values for one-sided equivalence, 0.0485 and 0.0516, respectively; delta = 10%), with no significant differences among patients with bacteremia and other microbiologically or clinically documented infections and fever of unknown origin. For 82 (66.1%) patients, it was possible to switch from parenteral ciprofloxacin to the oral ciprofloxacin, and the response was successful for 61 (74.4%) patients. The efficacies of the regimens against streptococcal bacteremias were 16.6% (one of six patients) for the ciprofloxacin group and 33.3% (one of three patients) for the combination group (it was not statistically significant), with one breakthrough streptococcal bacteremia observed among the ciprofloxacin-treated patients. Adverse events were mostly self-limited and were observed in 27 (20.6%) ciprofloxacin-treated patients and 26 (19.7%) patients who were receiving the combination. This study demonstrates that high-dose ciprofloxacin given intravenously for at least 3 days and then by the oral route is therapeutically equivalent to the routine regimen of intraveneous ceftazidime plus amikacin even in febrile patients with severe neutropenia (polymorphonuclear leukocyte count, <100 mm(3)). However, it is very important that before an empirical therapy is chosen each hospital determine bacteriologic predominance and perform resistance surveillance.

Bacterial infections in terminally ill hospice patients

Terminally ill patients are very susceptible to infections, which are the result of disease-related processes and/or therapy-induced mechanisms. These patients are already subject to multiple severe symptoms and associated comorbid conditions, with much resultant distress. Infection increases this symptom burden and further reduces quality of life. We have retrospectively investigated the prevalence of infection and clinical course in 102 consecutive patients who died after admission to a tertiary palliative care unit and assessed the site-specific frequency of infection, pathogenic organisms involved, and the pattern of antibiotic agents used. The prevalence of symptoms and comorbid conditions on admission and during the progress phase of care were noted. Median overall survival of the total cohort was 12 days. The median survival of patients with infections was 22 days. Thirty-seven patients (36.3%) were diagnosed with 42 separate infections. The sites of infections were the urinary tract (42.5%), the respiratory tract (22.9%), blood (12.5%), skin and subcutaneous tissues (12.5%), and the eyes (10.0%). There were 20 separate positive cultures isolated from specimens obtained from 13 individual patients. Three isolates were obtained from 1 patient, 2 isolates obtained from 5 patients, and 1 isolate was obtained from each of the 7 remaining patients. Escherichia coli was the most common pathogen isolated. Eleven patients with infections (31.4%) were diagnosed on admission, and antibiotic treatment was commenced within 48 hours of admission in 21 patients (60%). Overall antibiotic response and symptom control of infections was observed to be a minimum of 40%. Psychological distress was common in this group of patients (P = 0.001) as were disabling symptoms on admission, such as pain, immobility, and weakness. Symptoms indicating poor survival, such as severe pain and dyspnea, were not significantly associated with infection. Decreased patient survival in this cohort was not significantly associated with the presence of bacterial infection (P = 0.07), irrespective of whether or not a positive culture isolate was obtained. We conclude that appropriate management of infection resulted in enhanced palliative symptom control.

Clinical use of the fluoroquinolones

The appetite for modification to the basic quinolone nucleus has grown logarithmically since the first quinolone was employed in clinical practice. Important structural refinements have led to expanded microbiologic activity, optimal pharmacokinetics, and increased safety profiles. The practicing clinician and researcher may glean considerable information from the quinolone structure with regard to microbiologic spectra and safety before administering these agents to patients. Although some toxicities can be ominously predictable, such as with the so-called high-risk quinolones (e.g., double-halogenated and trifluorinated quinolones), clinicians must rely on animal models of toxicity and clinical trial data to discern other toxicities (e.g., Q-Tc interval prolongation). A few quinolones enjoy a relatively clean safety profile and are well tolerated (e.g., gatifloxacin, levofloxacin, ciprofloxacin). Other quinolones may be associated with significant collateral system toxicity during therapy; however, under certain conditions, albeit rare, their potential for benefit may outweigh the existing risk. Clinafloxacin, for use in the management of lung infections caused by multiply resistant B. cepacia in cystic fibrosis patients, is an example of a risk that may be outweighed by its therapeutic benefit. Because there are many treatment alternatives within the clinician's armamentarium, the obligation is to select the safest, most therapeutically effective, and most cost-effective agent that is available. In addition to increasing mortality and morbidity, the development of toxicity or an adverse event during therapy may compromise the immediate effectiveness of treatment as well as affect the cost of the patient's care significantly. With the immediate abundance of quinolones available for use, the safest, most effective, and best-tolerated agents will likely emerge as the most appropriate therapeutic choices when a quinolone is indicated.

Time to clinical response: an outcome of antibiotic therapy of febrile neutropenia with implications for quality and cost of care

PURPOSE

To determine whether antibiotic regimens with similar rates of response differ significantly in the speed of response and to estimate the impact of this difference on the cost of febrile neutropenia.

METHODS

The time point of clinical response was defined by comparing the sensitivity, specificity, and predictive values of alternative objective and subjective definitions. Data from 488 episodes of febrile neutropenia, treated with either of two commonly used antibiotics (coded A or B) during six clinical trials, were pooled to compare the median time to clinical response, days of antibiotic therapy and hospitalization, and estimated costs.

RESULTS

Response rates were similar; however, the median time to clinical response was significantly shorter with A-based regimens (5 days) compared with B-based regimens (7 days; P =.003). After 72 hours of therapy, 33% of patients who received A but only 18% of those who received B had responded (P =.01). These differences resulted in fewer days of antibiotic therapy and hospitalization with A-based regimens (7 and 9 days) compared with B-based regimens (9 and 12 days, respectively; P <.04) and in significantly lower estimated median costs ($8,491 v $11,133 per episode; P =.03). Early discharge at the time of clinical response should reduce the median cost from $10,752 to $8,162 (P <.001).

CONCLUSION

Despite virtually identical rates of response, time to clinical response and estimated cost of care varied significantly among regimens. An early discharge strategy based on our definition of the time point of clinical response may further reduce the cost of treating non-low-risk patients with febrile neutropenia.

Colony stimulating factors in patients with fever and neutropenia

Colony stimulating factors (CSFs), are essential for the regulation of the hematopoietic system and were developed by the pharmaceutical biotechnology industry in the early 1990s for the prevention of serious neutropenic complication after myelosuppressive chemotherapy. Both G-CSF and GM-CSF consistently lead to an increase in circulating white blood cells and a reduction in the incidence of fever and neutropenia after myelosuppressive chemotherapy in patients with solid tumors, hematologic malignancies, and those undergoing stem-cell transplantation. Their role in improving response rates to chemotherapy and overall survival is less clear.

Clinical and laboratory features predicting a favorable outcome and allowing early discharge in cancer patients with low-risk febrile neutropenia: a literature review

To value feasibility of early discharge in febrile granulocytopenic patients, 27 original paper published in the last 11 years were analyzed concerning these clinical and therapeutic approaches. A Medline search of English language literature published in the last 11 years (1988-1999) used the key words neutropenia, fever, cancer, home-antibiotic therapy, short course of antibiotic therapy, and early discharge. Twenty-seven original papers fulfilling the study criteria were identified. In these studies, 5208 episodes were evaluated: there were 538 failures with 87 deaths. Features of low-risk patients who developed life-threatening infectious disease were related to general clinical condition, cancer control, bone marrow function, presence of clinical signs of infection, and social features. Careful risk assessment can allow safe recognition of low-risk patients with febrile neutropenia who can be discharged early and can be used to follow outpatient treatment programs to improve patients' quality of life as well as the use of economic resources.

Febrile neutropenia in children

Fever is frequent in neutropenic patients and often related to infection. Two major concepts, have contributed to the marked mortality decrease of those patients by the end of the 1960s: firstly, the duration and severity of neutropenia were the most important variables linked to infection and secondly, prompt administration of broad-spectrum antimicrobials empirically, was life-saving. At the same time it was universally admitted that a careful daily examination of all portals of entry for micro-organisms was mandatory and that laboratory and imaging investigations were needed at regular intervals, keeping constantly in mind the individual type and stage of immunosuppression. Through many studies, paediatricians contributed markedly in standardisation of management of febrile neutropenic patients. Neutropenic patients are not equally prone to infections, partly due to the underlying cancer, chemotherapy and co-morbidity factors. Neutropenic children are not only vulnerable to bacteria, fungi and viruses commonly encountered in adults, but also to common viruses and bacteria. Very few studies included a viral work-up. Epidemiological new trends are observed: Gram-positive bacteria and fungi are on the rise. Simplifying and shortening antibiotic regimens were made possible because new potent antibiotics were launched. Since the mid-1980s, many paediatric centres commonly discharge patients before complete bone marrow recovery, provided that patients meet certain low-risk criteria and do not exhibit any clinical or biological evidence of bacterial infection. However, a few prospective randomised studies have been conducted for assessing the safety of early antibiotics discontinuation and safe early discharge. The choice of oral agents up to now was complicated by the reluctance using fluoroquinolones in children. New challenges are numerous in terms of diagnostic tools, detection of epidemiological trends and emerging pathogens, identification and control of nosocomial threats including drug resistance, assessment of the real impact of prophylaxis, evaluation of new agents, the need for more accurate risk scoring systems, outpatient management and the necessity for an optimal use of resources.

Prediction of neutropenia

Newer treatment strategies for the management of febrile neutropenic patients are being developed. These include: (a) hospital based oral therapy; (b) early discharge after initial stabilization in-hospital, and (c) out-patient therapy. All strategies are likely to be more successful in patients with short-lived neutropenia (< or = 7 days) than in those with more prolonged neutropenia. Although risk-prediction rules and clinical criteria can help clinicians identify 'low-risk' neutropenic patients, the overall ability of clinicians to accurately predict the subsequent duration of neutropenia once a neutropenic patient becomes febrile needs to be improved upon considerably. One attempt to do so is the survey being conducted by the Infection Study Section of the Multinational Association of Supportive Care in Cancer (MASCC). Development of an accurate rule for the prediction of neutropenia will enable more appropriate, risk-based therapy to be administered to febrile neutropenic patients, and will represent a significant advance in the management of such patients.

Risk factors assessment in fabrile neutropenia

It is now established that febrile neutropenic cancer patients constitute a heterogeneous population with a variable risk for serious medical complication development. Optimal patient management should take that risk into account by replacing, for instance, the classical, in-hospital administered, broad-spectrum intravenous antibiotics by newer therapeutic approaches including oral and/or outpatient therapeutic strategies for the 'low-risk' patients. The development of such approaches which have been shown safe and feasible, implies the existence of universally accepted, validated and reliable clinical prediction rules for the identification of these low-risk patients. Some prognostic factors predicting the response to the empiric treatment, the development of a bacteremia, and the final outcome of a febrile neutropenic episode have been established (such as duration and profoundness of neutropenia, acute leukemia, administration of chemotherapy for treatment of relapse, high temperature, shock and/or chills, inpatient status at fever onset) and some models combining them have already been proposed, firstly by Talcott and coworkers and more recently by the Multinational Association for Supportive Care in Cancer (MASCC) study section on infections. The sensitivity of these rules as a selection tool for identifying patients at low-risk of complication, however, needs to be improved and we have to assess their clinical usefulness, safety and/or reproducibility better in order to allow a more adequate choice between the therapeutic strategies, to continue to improve patients quality of life and to optimize the cost-effectiveness of the treatments.

Unusual infections and novel therapy in the immunocompromised host

New methods of identification have led to an ever-increasing number of unusual pathogens causing infection in the immunocompromised host. Reports of antimicrobial-resistant organisms in this group of patients are also increasing, with the result that new treatments must be sought urgently. New agents and new strategies for the development of antimicrobial agents are critical for future progress in the treatment of resistant organisms.

The Multinational Association for Supportive Care in Cancer risk index: A multinational scoring system for identifying low-risk febrile neutropenic cancer patients

PURPOSE

Febrile neutropenia remains a potentially life-threatening complication of anticancer chemotherapy, but some patients are at low risk for serious medical complications. The purpose of this study was to develop an internationally validated scoring system to identify these patients.

MATERIALS AND METHODS

Febrile neutropenic cancer patients were observed in a prospective multinational study. Independent factors assessable at fever onset, predicting low risk of complications, on a randomly selected derivation set, were assigned integer weights to develop a risk-index score, which was subsequently tested on a validation set.

RESULTS

On the derivation set (756 patients), predictive factors were a burden of illness indicating absence of symptoms or mild symptoms (weight, 5; odds ratio [OR], 8.21; 95% confidence interval [CI], 4.15 to 16.38) or moderate symptoms (weight, 3; OR, 3.70; 95% CI, 2.18 to 6.29); absence of hypotension (weight, 5; OR, 7.62; 95% CI, 2.91 to 19.89); absence of chronic obstructive pulmonary disease (weight, 4; OR, 5. 35; 95% CI, 1.86 to 15.46); presence of solid tumor or absence of previous fungal infection in patients with hematologic malignancies (weight, 4; OR, 5.07; 95% CI, 1.97 to 12.95); outpatient status (weight, 3; OR, 3.51; 95% CI, 2.02 to 6.04); absence of dehydration (weight, 3; OR, 3.81; 95% CI, 1.89 to 7.73); and age less than 60 years (weight, 2; OR, 2.45; 95% CI, 1.51 to 4.01). On the validation set, a Multinational Association for Supportive Care in Cancer risk-index score >/= 21 identified low-risk patients with a positive predictive value of 91%, specificity of 68%, and sensitivity of 71%.

CONCLUSION

The risk index accurately identifies patients at low risk for complications and may be used to select patients for testing therapeutic strategies that may be more convenient or cost-effective.

Update in internal medicine

More than 500,000 new medical articles are published every year and available time to keep updated is scarcer every day. Nowadays, the task of selecting useful, consistent, and relevant information for clinicians is a priority in many major medical journals. This review has the aim of gathering the results of the most important findings in clinical medicine in the last few years. It is focused on results from randomized clinical trials and well-designed observational research. Findings were included preferentially if they showed solid results, and we avoided as much as possible including only preliminary data, or results that included only non-clinical outcomes. Some of the most relevant findings reported here include the significant benefit of statins in patients with coronary artery disease even with mean cholesterol level. It also provides a substantial review of the most significant trials assessing the effectiveness of IIb/IIIa receptor blockers. In gastroenterology many advances have been made in the H. pylori eradication, and the finding that the cure of H. pylori infection may be followed by gastroesophageal reflux disease. Some new antivirals have shown encouraging results in patients with chronic hepatitis. In the infectious disease arena, the late breaking trials in anti-retroviral disease are discussed, as well as the new trends regarding antibiotic resistance. This review approaches also the role of leukotriene modifiers in the treatment of asthma and discusses the benefit of using methylprednisolone in patients with adult respiratory distress syndrome, among many other advances in internal medicine.