Clinical efficacy of β-lactam/β-lactamase inhibitor combinations for the treatment of bloodstream infection due to extended-spectrum β-lactamase-producing Enterobacteriaceae in haematological patients with neutropaenia: a study protocol for a retrospective observational study (BICAR)

INTRODUCTION

Bloodstream infection (BSI) due to extended-spectrum β-lactamase-producing Gram-negative bacilli (ESBL-GNB) is increasing at an alarming pace worldwide. Although β-lactam/β-lactamase inhibitor (BLBLI) combinations have been suggested as an alternative to carbapenems for the treatment of BSI due to these resistant organisms in the general population, their usefulness for the treatment of BSI due to ESBL-GNB in haematological patients with neutropaenia is yet to be elucidated. The aim of the BICAR study is to compare the efficacy of BLBLI combinations with that of carbapenems for the treatment of BSI due to an ESBL-GNB in this population.

METHODS AND ANALYSIS

A multinational, multicentre, observational retrospective study. Episodes of BSI due to ESBL-GNB occurring in haematological patients and haematopoietic stem cell transplant recipients with neutropaenia from 1 January 2006 to 31 March 2015 will be analysed. The primary end point will be case-fatality rate within 30 days of onset of BSI. The secondary end points will be 7-day and 14-day case-fatality rates, microbiological failure, colonisation/infection by resistant bacteria, superinfection, intensive care unit admission and development of adverse events.

SAMPLE SIZE

The number of expected episodes of BSI due to ESBL-GNB in the participant centres will be 260 with a ratio of control to experimental participants of 2.

ETHICS AND DISSEMINATION

The protocol of the study was approved at the first site by the Research Ethics Committee (REC) of Hospital Universitari de Bellvitge. Approval will be also sought from all relevant RECs. Any formal presentation or publication of data from this study will be considered as a joint publication by the participating investigators and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE). The study has been endorsed by the European Study Group for Bloodstream Infection and Sepsis (ESGBIS) and the European Study Group for Infections in Compromised Hosts (ESGICH).

Current practices for treatment of respiratory syncytial virus and other non-influenza respiratory viruses in high-risk patient populations: a survey of institutions in the Midwestern Respiratory Virus Collaborative

Background

The optimal treatment for respiratory syncytial virus (RSV) infection in adult immunocompromised patients is unknown. We assessed the management of RSV and other non‐influenza respiratory viruses in Midwestern transplant centers.

Methods

A survey assessing strategies for RSV and other non‐influenza respiratory viral infections was sent to 13 centers.

Results

Multiplex polymerase chain reaction assay was used for diagnosis in 11/12 centers. Eight of 12 centers used inhaled ribavirin (RBV) in some patient populations. Barriers included cost, safety, lack of evidence, and inconvenience. Six of 12 used intravenous immunoglobulin (IVIG), mostly in combination with RBV. Inhaled RBV was used more than oral, and in the post‐stem cell transplant population, patients with lower respiratory tract infection (LRTI), graft‐versus‐host disease, and more recent transplantation were treated at higher rates. Ten centers had experience with lung transplant patients; all used either oral or inhaled RBV for LRTI, 6/10 treated upper respiratory tract infection (URTI). No center treated non‐lung solid organ transplant (SOT) recipients with URTI; 7/11 would use oral or inhaled RBV in the same group with LRTI. Patients with hematologic malignancy without hematopoietic stem cell transplantation were treated with RBV at a similar frequency to non‐lung SOT recipients. Three of 12 centers, in severe cases, treated parainfluenza and metapneumovirus, and 1/12 treated coronavirus.

Conclusions

Treatment of RSV in immunocompromised patients varied greatly. While most centers treat LRTI, treatment of URTI was variable. No consensus was found regarding the use of oral versus inhaled RBV, or the use of IVIG. The presence of such heterogeneity demonstrates the need for further studies defining optimal treatment of RSV in immunocompromised hosts.

Fecal microbiota transplantation for fulminant Clostridium difficile infection in an allogeneic stem cell transplant patient

We present a case of severe Clostridium difficile infection (CDI) in a non-neutropenic allogeneic hematopoietic stem cell transplant recipient who was treated successfully with fecal microbiota therapy after standard pharmacologic therapy had failed. Following naso-jejunal instillation of donor stool, the patient's symptoms resolved within 48 h. Bowel resection was averted. This is the first case in the literature, to our knowledge, to describe fecal microbiota therapy in a profoundly immunocompromised host with severe CDI. We propose that fecal microbiota therapy be considered as a therapeutic option in immunosuppressed patients with refractory severe CDI.

Paecilomyces lilacinus infection in a liver transplant patient: case report and review of the literature

A 56-year-old male who was 12 months status post liver transplant presented with a 2-month history of painful, erythematous nodules over the right knee. Several biopsies yielded a mold initially phenotypically identified as a Penicillium species, but molecular sequence analysis ultimately determined the identity as Paecilomyces lilacinus. Several courses of oral voriconazole were required for resolution of the infection. A review of the literature revealed that Paecilomyces species are an infrequent cause of disease in transplant patients, with skin and soft tissue infections being the most common presentation. It is important to accurately identify these infections, and polymerase chain reaction assay using universal fungal primers offers a rapid and precise diagnostic approach. Treatment of Paecilomyces infections may require multiple courses of antifungal therapy, often with surgical debridement. We suggest that voriconazole may be a useful treatment alternative to the more traditional therapy with amphotericin B-based agents.

Thromboembolism following removal of femoral venous apheresis catheters in patients with breast cancer

BACKGROUND

Apheresis catheters have simplified collection of peripheral blood stem cells (PBSC), but may be associated with thrombosis of the instrumented vessels. We performed a retrospective analysis to study the prevalence of thromboembolism associated with the use of femoral apheresis catheters in patients with breast cancer.

PATIENTS AND METHODS

Patients were participants in clinical trials of high-dose chemotherapy with autologous PBSC rescue. They underwent mobilization with either high-dose cyclophosphamide (n = 21) or cyclophosphamide/paclitaxel (n = 64), followed by filgrastim. Double lumen catheters (12 or 13 Fr) were placed in the femoral vein and removed within 12 h of the last apheresis procedure. Apheresis was performed using a continuous flow cell separator and ACD-A anticoagulant. Thromboembolism was diagnosed by either venous ultrasonography or ventilation-perfusion scan.

RESULTS

Nine of 85 patients (10.6%) undergoing large volume apheresis with use of a femoral catheter developed thromboembolic complications. Pulmonary embolus (PE) was diagnosed in five and femoral vein thrombosis in four patients. Four of the five patients who developed PE were symptomatic; one asymptomatic patient had a pleural-based, wedge-shaped lesion detected on a staging computed tomography scan. The mean number of apheresis procedures was 2.4 (range one to four) and the mean interval between removal of the apheresis catheter and diagnosis of thrombosis was 17.6 days. In contrast, none of 18 patients undergoing apheresis using jugular venous access and none of 54 healthy allogeneic donors undergoing concurrent filgrastim-mobilized PBSC donation (mean 1.7 procedures/donor) using femoral access experienced thromboembolic complications.

CONCLUSIONS

Thromboembolism following femoral venous catheter placement for PBSC collection in patients with breast cancer may be more common than previously recognized. Healthy PBSC donors are not at the same risk. Onset of symptoms related to thrombosis tended to occur several weeks after catheter removal. This suggests that the physicians not only need to be vigilant during the period of apheresis, but also need to observe patients for thromboembolic complications after the catheter is removed. The long interval between the removal of apheresis catheter and the development of thromboembolism may have a potential impact on prophylactic strategies developed in future, such as the duration of prophylactic anticoagulation. Avoidance of the femoral site in breast cancer patients, and close prospective monitoring after catheter removal, are indicated.

Immunohistochemical and in situ hybridization studies of influenza A virus infection in human lungs

Influenza viruses are responsible for acute febrile respiratory disease. When deaths occur, definitive diagnosis requires viral isolation because no characteristic viral inclusions are seen. We examined the distribution of influenza A virus in tissues from 8 patients with fatal infection using 2 immunohistochemical assays (monoclonal antibodies to nucleoprotein [NP] and hemagglutinin [HA]) and 2 in situ hybridization (ISH) assays (digoxigenin-labeled probes that hybridized to HA and NP genes). Five patients had prominent bronchitis; by immunohistochemical assay, influenza A staining was present focally in the epithelium of larger bronchi (intact and detached necrotic cells) and in rare interstitial cells. The anti-NP antibody stained primarily cell nuclei, and the anti-HA antibody stained mainly the cytoplasm. In 4 of these cases, nucleic acids (ISH) were identified in the same areas. Three patients had lymphohistiocytic alveolitis and showed no immunohistochemical or ISH staining. Both techniques were useful for detection of influenza virus antigens and nucleic acids in formalin-fixed paraffin-embedded tissues and can enable further understanding of fatal influenza A virus infections in humans.

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

BACKGROUND

Among patients with fever and neutropenia during chemotherapy for cancer who have a low risk of complications, oral administration of empirical broad-spectrum antibiotics may be an acceptable alternative to intravenous treatment.

METHODS

We conducted a randomized, double-blind, placebo-controlled study of patients (age, 5 to 74 years) who had fever and neutropenia during chemotherapy for cancer. Neutropenia was expected to be present for no more than 10 days in these patients, and they had to have no other underlying conditions. Patients were assigned to receive either oral ciprofloxacin plus amoxicillin-clavulanate or intravenous ceftazidime. They were hospitalized until fever and neutropenia resolved.

RESULTS

A total of 116 episodes were included in each group (84 patients in the oral-therapy group and 79 patients in the intravenous-therapy group). The mean neutrophil counts at admission were 81 per cubic millimeter and 84 per cubic millimeter, respectively; the mean duration of neutropenia was 3.4 and 3.8 days, respectively. Treatment was successful without the need for modifications in 71 percent of episodes in the oral-therapy group and 67 percent of episodes in the intravenous-therapy group (difference between groups, 3 percent; 95 percent confidence interval, -8 percent to 15 percent; P=0.48). Treatment was considered to have failed because of the need for modifications in the regimen in 13 percent and 32 percent of episodes, respectively (P<0.001) and because of the patient's inability to tolerate the regimen in 16 percent and 1 percent of episodes, respectively (P<0.001). There were no deaths. The incidence of intolerance of the oral antibiotics was 16 percent, as compared with 8 percent for placebo (P=0.07).

CONCLUSIONS

In hospitalized low-risk patients who have fever and neutropenia during cancer chemotherapy, empirical therapy with oral ciprofloxacin and amoxicillin-clavulanate is safe and effective.

Safety, tolerance, and pharmacokinetics of a small unilamellar liposomal formulation of amphotericin B (AmBisome) in neutropenic patients

The safety, tolerance, and pharmacokinetics of a small unilamellar liposomal formulation of amphotericin B (AmBisome) administered for empirical antifungal therapy were evaluated for 36 persistently febrile neutropenic adults receiving cancer chemotherapy and bone marrow transplantation. The protocol was an open-label, sequential-dose-escalation, multidose pharmacokinetic study which enrolled a total of 8 to 12 patients in each of the four dosage cohorts. Each cohort received daily doses of either 1.0, 2.5, 5.0, or 7.5 mg of amphotericin B in the form of AmBisome/kg of body weight. The study population consisted of patients between the ages of 13 and 80 years with neutropenia (absolute neutrophil count, <500/mm3) who were eligible to receive empirical antifungal therapy. Patients were monitored for safety and tolerance by frequent laboratory examinations and the monitoring of infusion-related reactions. Efficacy was assessed by monitoring for the development of invasive fungal infection. The pharmacokinetic parameters of AmBisome were measured as those of amphotericin B by high-performance liquid chromatography. Noncompartmental methods were used to calculate pharmacokinetic parameters. AmBisome administered as a 1-h infusion in this population was well tolerated and was seldom associated with infusion-related toxicity. Infusion-related side effects occurred in 15 (5%) of all 331 infusions, and only two patients (5%) required premedication. Serum creatinine, potassium, and magnesium levels were not significantly changed from baseline in any of the dosage cohorts, and there was no net increase in serum transaminase levels. AmBisome followed a nonlinear dosage relationship that was consistent with reticuloendothelial uptake and redistribution. There were no breakthrough fungal infections during empirical therapy with AmBisome. AmBisome administered to febrile neutropenic patients in this study was well tolerated, was seldom associated with infusion-related toxicity, was characterized by nonlinear saturation kinetics, and was effective in preventing breakthrough fungal infections.

Use of fluoroquinolones for empirical management of febrile neutropenia in pediatric cancer patients

BACKGROUND

Empiric antibiotic therapy has become a standard of care for the febrile neutropenic patient. Many clinical trials over the previous three decades have demonstrated that a variety of antibiotic combinations and more recently potent antibiotic monotherapies may preserve the patient through the critical time of fever and neutropenia. Recently attempts have been made to identify "low risk" patients who may not require traditional, intensive, hospitalized intravenous antimicrobial therapy. Therefore the need for new treatment alternatives for the febrile neutropenic pediatric cancer patient in particular revolves around the desire for less complex regimens, agents with minimal toxicity and expense and the option of an oral formulation for outpatient management.

OBJECTIVE

Fluoroquinolones, especially ciprofloxacin and ofloxacin, are examined in this paper as potential oral alternatives for managing the low risk neutropenic pediatric cancer patient population. Attention must be paid to their antibacterial spectra, however, and in some cases fluoroquinolones should be combined with a second agent for additional Gram-positive coverage.

RESULTS

Several studies, including one ongoing trial at the National Cancer Institute, have shown the potential benefits of oral fluoroquinolone therapy among low risk febrile neutropenic patients. Joint complaints in children after ciprofloxacin therapy in the National Cancer Institute trial thus far have been minimal, reversible and felt to be unrelated to ciprofloxacin treatment.

CONCLUSION

The use of outpatient therapy, such as the fluoroquinolones, to manage febrile neutropenic episodes must be approached with caution and should be undertaken only in selected low risk patients.

Rapid identification of respiratory viruses: impact on isolation practices and transmission among immunocompromised pediatric patients

OBJECTIVE

To determine whether empiric isolation of patients with acute respiratory virus infection symptoms could be discontinued when preliminary shell vial cultures were negative, and the impact of this approach on hospital resources.

DESIGN

In 1993, we retrospectively reviewed respiratory virus test results from 1992 to 1993 and extended data collection prospectively through the 1993 to 1994 season. The rapid test and 48-hour shell vial results were compared to a standard of rapid test plus 5-day shell vial culture results to determine the sensitivity and specificity of these "preliminary" results.

SETTING

A 400-bed tertiary referral research hospital.

PATIENTS

Patients from any inpatient unit or clinic with acute respiratory virus infection symptoms who had a specimen submitted for respiratory virus culture. Patients were placed on empiric respiratory isolation pending culture results.

RESULTS

The overall sensitivity of the combined rapid and 48-hour culture results in adults and children was 97%. All 15 pediatric patients with respiratory syncytial virus infection who had specimens submitted on first suspicion of respiratory virus infection were positive by rapid test. Culture results were positive within 48 hours for 100% of patients with influenza A (15 patients), influenza B (6), and parainfluenza (18) viruses. Of 59 pediatric inpatients who were isolated empirically awaiting 5-day culture results, 31 (52%) ultimately were determined to be culture negative.

CONCLUSIONS

Empiric isolation of symptomatic children can be discontinued at 48 hours when both the rapid test and the early culture results are negative. Our institution would have saved 93 days of unnecessary isolation over 2 years had such a policy been in place.

Early empiric antibiotic therapy for febrile neutropenia patients at low risk

Although it is apparent that certain patients with febrile neutropenic episodes can benefit from outpatient antibiotic therapy, not all low-risk patients are treated in this fashion. There are barriers, real and perceived, to implementing this approach for patients, health care providers, and caregivers. Table 3 summarizes the advantages and disadvantages of ambulatory management of febrile neutropenic patients. For many patients and physicians, outpatient oral antibiotics may be preferred, whereas for others a more conservative approach might be needed in order to feel comfortable with treating this population on an outpatient basis. In this situation, patients can be treated in a stepwise fashion as shown in Table 4. These alternatives allow physicians and patients options to discuss when planning treatment strategies for febrile neutropenia.

Suppression of polymorphonuclear leukocyte bactericidal activity by suramin

Suramin is a polyanionic compound with potent antineoplastic properties. Because polymorphonuclear leukocytes (PMNs) are a crucial component of host defenses against bacteria and fungi, the effects of suramin on PMN function were studied in vitro. PMNs from healthy donors were incubated with concentrations of suramin of 1 to 1,000 micrograms/ml (within and exceeding the therapeutic range) for 30 min, and PMN functional parameters were subsequently assessed. Suramin had no effect on viability, chemotaxis to N-formylmethionyl leucyl phenylalanine, phagocytosis of Candida albicans, or superoxide anion production in response to phorbol myristate acetate and formylmethionyl leucyl phenylalanine. Fungicidal activity against C. albicans blastoconidia was unaffected at a suramin concentration of < 500 micrograms/ml, whereas at higher concentrations a slight suppression was observed (P = 0.04). Bactericidal activity against Staphylococcus aureus was significantly suppressed by concentrations of > or = 100 micrograms/ml (P < 0.01). Phagocytosis of S. aureus was also significantly impaired at > or = 10 micrograms/ml (P < 0.05). The presence of 10% human serum during pretreatment did not abrogate the suramin-induced suppression of bactericidal activity. Treatment of PMNs with granulocyte colony-stimulating factor (4,000 U/ml) for 30 min prior to the addition of suramin (250 micrograms/ml) improved the bactericidal defect (P = 0.02). The PMN functional impairment may be related to increased susceptibility to bacterial infections, and granulocyte colony-stimulating factor may improve the defect.

NIH conference. Varicella-zoster virus infections. Biology, natural history, treatment, and prevention

During the last 10 years, there have been major advances in the understanding of varicella-zoster virus and the diseases it causes. The molecular biology of the virus is being unraveled with the aid of new molecular technologies. Varicella, usually a benign manifestation of primary infection, and zoster, a result of reactivation of latent virus, can cause considerable morbidity in patients with immune impairment. Antiviral drugs, especially acyclovir, ameliorate severe infections but still have little role in the treatment of most normal patients with varicella or zoster. Varicella can be prevented when necessary by patient isolation and passive prophylaxis with varicella-zoster immune globulin. An experimental live vaccine also prevents varicella, but problems regarding its virulence for immunosuppressed patients and the durability of the protective response are still being addressed.