Impact of Changes of the 2020 Consensus Definitions of Invasive Aspergillosis on Clinical Trial Design: Unintended Consequences for Prevention Trials?

Background

Consensus definitions for the diagnosis of invasive fungal diseases (IFDs) were updated in 2020 to increase the certainty of IFD for inclusion in clinical trials, for instance by increasing biomarker cutoff limits to define positivity. To date, there is a paucity of data as to the impact of the revised definitions on clinical trials.

Methods

In this study, we sought to determine the impact of the new definitions on classifying invasive aspergillosis (IA), the most common invasive mold disease in immunocompromised patients. We reclassified 226 proven and probable IA cases plus 139 possible IFD cases in the Aspergillus Technology Consortium (AsTeC) and in an antifungal prophylaxis trial (BMT CTN 0101) using the new criteria.

Results

Fewer cases met the more stringent diagnostic 2020 criteria after applying the reclassification criteria to define probable IA. Of 188 evaluable probable cases, 41 (22%) were reclassified to 40 possible IA and 1 probable IFD. Reclassification to possible IFD occurred in 22% of hematologic malignancy (HM) patients, 29% of hematopoietic cell transplant (HCT) patients, and in no lung transplant (LT) patients. Date of diagnosis was established a median (range) of 3 (1–105) days later in 15% of probable IA cases using the new criteria. Applying the new definitions to the BMT CTN 0101 trial, the power to detect the same odds ratio decreased substantially.

Conclusions

The updated IA consensus definitions may impact future trial designs, especially for antifungal prophylaxis studies.

Severity of Acute Graft-versus-Host Disease and Associated Healthcare Resource Utilization, Cost, and Outcomes

Acute graft-versus-host disease (aGVHD) contributes to poor outcomes and increased healthcare resource utilization (HRU) after allogeneic hematopoietic stem cell transplantation (HCT). However, HRU and the economic burden of aGVHD based on severity of the disease is not well characterized. Our study cohort comprised 290 adults who underwent allogeneic HCT between 2010 and 2018. Costs, HRU, and all-cause mortality in the 100-day and 365-day periods after HCT were compared between patients with aGVHD and those without aGVHD. The impact of aGVHD severity and gastrointestinal (GI) involvement on mortality, HRU, and economic burden was also evaluated. Medical costs and total hospital length of stay (LOS) were retrieved from administrative data that allocate costs to services based on departmental input for resource use and were adjusted to 2018 dollars. The Wilcoxon rank-sum test was used to compare the number of inpatient days and total costs. Multivariable linear regression was fitted on log-transformed costs. Compared with patients without aGVHD, those with aGVHD had a significantly greater median hospital LOS (28 days versus 22 days) and higher rates of intensive care unit (ICU) admission (13% versus 6%) and rehospitalization (59% versus 38%) during the first 100 days post-HCT. The presence of grade I-II aGVHD significantly prolonged the hospital LOS by a median of 3 days and increased the readmission rate by 18%, whereas grade III-IV aGVHD was associated with a nearly 30% increase in the readmission rate and a doubling of inpatient LOS, ICU admission rate, and mortality in the first 100 days post-HCT. Compared with the absence of aGVHD, lower GI involvement in aGVHD was also associated with increased risk of readmission (30%) and twice as many inpatient days, doubling the likelihood of ICU admission and mortality over the first 100 days. Similar findings were observed over days 101 to 365 post-HCT. The mean cost attributable to aGVHD regardless of grade was $60,923 in the first 100 days post-HCT. This cost varied by grade. The mean aGVHD- attributable costs were $18,071 for grade I, $36,115 for grade II and $120,929 for grade III/IV aGVHD and $114,668 for aGVHD involving the lower GI tract. In the 101- to 365-day period, the mean attributable aGVHD cost regardless of grade was $17,527. This cost also varied by grade. There were no additional aGVHD-attributable costs for grade I, but the mean aGVHD-attributable costs were $9743 for grade II, $62,220 for grade III/IV, and $55,724 for aGVHD with lower GI involvement compared with the controls without aGVHD. High-grade aGVHD and GI involvement in aGVHD, especially lower GI aGVHD, is associated with a considerably increased mortality and healthcare economic burden. Therefore, it is imperative that new therapeutic strategies be developed for this patient population.

Characteristics of Late Fatal Infections after Allogeneic Hematopoietic Cell Transplantation

We analyzed late fatal infections (LFIs) in allogeneic stem cell transplantation (HCT) recipients reported to the Center for International Blood and Marrow Transplant Research. We analyzed the incidence, infection types, and risk factors contributing to LFI in 10,336 adult and 5088 pediatric subjects surviving for ≥2 years after first HCT without relapse. Among 2245 adult and 377 pediatric patients who died, infections were a primary or contributory cause of death in 687 (31%) and 110 (29%), respectively. At 12 years post-HCT, the cumulative incidence of LFIs was 6.4% (95% confidence interval [CI], 5.8% to 7.0%) in adults, compared with 1.8% (95% CI, 1.4% to 2.3%) in pediatric subjects; P < .001). In adults, the 2 most significant risks for developing LFI were increasing age (20 to 39, 40 to 54, and ≥55 years versus 18 to 19 years) with hazard ratios (HRs) of 3.12 (95% CI, 1.33 to 7.32), 3.86 (95% CI, 1.66 to 8.95), and 5.49 (95% CI, 2.32 to 12.99) and a history of chronic graft-versus-host disease GVHD (cGVHD) with ongoing immunosuppression at 2 years post-HCT compared with no history of GVHD with (HR, 3.87; 95% CI, 2.59 to 5.78). In pediatric subjects, the 3 most significant risks for developing LFI were a history of cGVHD with ongoing immunosuppression (HR, 9.49; 95% CI, 4.39 to 20.51) or without ongoing immunosuppression (HR, 2.7; 95% CI, 1.05 to 7.43) at 2 years post-HCT compared with no history of GVHD, diagnosis of inherited abnormalities of erythrocyte function compared with diagnosis of acute myelogenous leukemia (HR, 2.30; 95% CI, 1.19 to 4.42), and age >10 years (HR, 1.92; 95% CI, 1.15 to 3.2). This study emphasizes the importance of continued vigilance for late infections after HCT and institution of support strategies aimed at decreasing the risk of cGVHD.

Abstract 3253: Droplet digital PCR is a sensitive method for detecting refractory acute myeloid leukemia (AML) clones in peripheral blood and saliva

Droplet digital PCR (ddPCR) is a highly sensitive and rapid method for detecting mutant allele frequency (MAF). In preliminary work, our lower limit of detection for common myeloid gene mutations was 0.001% in peripheral blood and bone marrow compared to 0.1% with flow cytometry and 0.01% with real-time quantitative PCR, and turnaround time is 1 day. Furthermore, we detected leukemic mutant alleles in peripheral blood (PB), introducing the possibility of sparing painful bone marrow biopsy procedures to determine treatment response. Thus, we hypothesized that ddPCR is a feasible and accurate method for monitoring leukemic disease burden in PB for the prospective care of patients (pts) with AML. Eighteen patients (pts) with de novo, relapse/refractory, and secondary AML were recruited to an IRB-approved study (NCT02435550) and bone marrow (BM), peripheral blood (PB), and saliva were collected at standard clinical visits. Gene mutations were identified by whole-exome sequencing (WES) of BM specimens at study entry. For ddPCR interrogation, genomic DNA was isolated (Qiagen), and select primers and probes (Bio-Rad/IDT) were developed based on variants identified in WES data. Case-specific primers and probes were validated on archived specimens obtained at study entry. 12/18 pt mutanomes met criteria for primer/probe design. 8 pts are in the primer/probe design and validation stage and 4 have completed validation and serial analyses. WES identified, and ddPCR confirmed, at least 1 mutation per patient at the study entry timepoint. The mutations included NRAS G13R, NRAS G12A, CSF3R T618I, and IDH2 R172K. In 2 cases, we observed a reduction in both PB and saliva MAF that were consistent with the reduction in both BM and PB blasts after treatment, resulting in complete remissions. Although PB blasts were reduced in a third pt receiving ruxolitinib, the persistence of their CSF3R MAF in PB indicated a resistant AML clone. WES revealed the presence of NRAS G13R variant in a secondary AML pt; however, WES did not detect this NRAS G13R variant in a cryopreserved BM specimen obtained at the pts MDS diagnosis. Interestingly, ddPCR was able to detect NRAS G13R variant at 0.1% MAF in a PB sample obtained at MDS diagnosis, demonstrating the ultrasensitive detection of rare variants within a sample, and highlighting the subclonal evolution of this pt's malignancy. Rapid detection of myeloid-related somatic mutations in a variety of tissue sources (i.e., saliva, PB) will allow for noninvasive monitoring of AML tumor burden. ddPCR may be used to observe molecular response to treatment and to detect molecular residual disease and relapse prior to clinically indicated BM biopsies.

Citation Format: Kimberly E. Hawkins, Cesia Salan, Madeleine Turcotte, Lauren T. Vaughn, Mei Zhang, Yanping Zhang, Barry Sawicki, Glenda G. Anderson, Nosha Farhadfar, Hemant S. Murthy, Biljana N. Horn, Helen L. Leather, Paul Castillo, Maxim Norkin, John W. Hiemenz, Randy A. Brown, William Slayton, Jack W. Hsu, John R. Wingard, Christopher R. Cogle, Leylah M. Drusbosky. Droplet digital PCR is a sensitive method for detecting refractory acute myeloid leukemia (AML) clones in peripheral blood and saliva [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3253.

Conditioning chemotherapy dose adjustment in obese patients: a review and position statement by the American Society for Blood and Marrow Transplantation practice guideline committee

Hematopoietic stem cell transplantation (HCT) is a potentially life-saving therapy for patients with malignant and nonmalignant disease states. This article reviews the current published literature on the dosing of pharmacologic agents used for HCT preparative regimens with specific focus on the obese patient population. The review found that dose adjustments for obesity have, to date, been based empirically or extrapolated from published data in the nontransplantation patient population. As a result, the Committee determined that clear standards or dosing guidelines are unable to be made for the obese population because Level I and II evidence are unavailable at this time. Instead, the Committee provides a current published literature review to serve as a platform for conditioning agent dose selection in the setting of obesity. A necessary goal should be to encourage future prospective trials in this patient population because further information is needed to enhance our knowledge of the pharmacokinetics and pharmacodynamics of conditioning agents in the setting of obesity.

Use of bronchoalveolar lavage to detect galactomannan for diagnosis of pulmonary aspergillosis among nonimmunocompromised hosts

Pulmonary aspergillosis in nonimmunocompromised hosts, although rare, is being increasingly recognized. The diagnosis of pulmonary aspergillosis is difficult, since the recovery of Aspergillus from respiratory samples cannot differentiate colonization from invasion. We assessed the role of bronchoalveolar lavage (BAL) in detecting galactomannan (GM) for diagnosing pulmonary aspergillosis in 73 nonimmunocompromised patients with pulmonary infiltrates for whom the test was ordered. Six patients had pulmonary aspergillosis, two each with acute invasive pulmonary aspergillosis, chronic necrotizing pulmonary aspergillosis, and aspergilloma. All six patients had a BAL GM level of >/=1.18. The sensitivity, specificity, and negative predictive value (NPV) for a BAL GM level of >/=1.0 were 100%, 88.1%, and 100%, respectively. Notably, the positive predictive value (PPV) was only 42.9%, likely reflecting the low prevalence of pulmonary aspergillosis among nonimmunosuppressed patients. The combination of BAL microscopy and culture had a sensitivity and NPV similar to those of BAL GM detection but a higher specificity and PPV (92.5% and 54.6%, respectively). Moreover, a BAL GM test did not identify any cases that were not diagnosed by conventional methods like microscopy and culture. In conclusion, there was no conclusive benefit of determining BAL GM levels in the diagnosis of pulmonary aspergillosis among nonimmunocompromised hosts. Given the likelihood of false-positive results, a BAL GM test should not be ordered routinely in this population.

Bronchoalveolar lavage galactomannan in diagnosis of invasive pulmonary aspergillosis among solid-organ transplant recipients

We review the experience at our institution with galactomannan (GM) testing of bronchoalveolar lavage (BAL) fluid in the diagnosis of invasive pulmonary aspergillosis (IPA) among solid-organ transplant recipients. Among 81 patients for whom BAL GM testing was ordered (heart, 24; kidney, 22; liver, 19; lung, 16), there were five cases of proven or probable IPA. All five patients had BAL GM of > or = 2.1 and survived following antifungal therapy. The sensitivity, specificity, and positive and negative predictive values for BAL GM testing at a cutoff of > or = 1.0 were 100%, 90.8%, 41.7%, and 100%, respectively. The sensitivity of BAL GM testing was better than that of conventional tests such as serum GM or BAL cytology and culture. Moreover, a positive BAL GM test diagnosed IPA several days to 4 weeks before other methods for three patients. Twelve patients had BAL GM of > or = 0.5 but no evidence of IPA. Among these, lung transplant recipients accounted for 41.7% (5/12) of the false-positive results, reflecting frequent colonization of airways in this population. Excluding lung transplants, the specificity and positive predictive value for other solid-organ transplants increased to 92.9% and 62.5%, respectively (cutoff, > or = 1.0). In conclusion, BAL GM testing facilitated more-rapid diagnoses of IPA and the institution of antifungal therapy among non-lung solid-organ transplant recipients and helped to rule out IPA.

Pharmacoeconomic analysis of caspofungin versus liposomal amphotericin B as empirical antifungal therapy for neutropenic fever

PURPOSE

An analysis was conducted that evaluated and compared the cost differences between caspofungin and liposomal amphotericin B when the medications were used as empirical antifungal therapy for persistent fever during neutropenia.

METHODS

Rates of drug use and impaired renal function (IRF) were based on data from published studies. IRF was defined as a doubling of the serum creatinine level or, if the creatinine level was elevated at enrollment, an increase of at least 1 mg/dL. The estimates of the costs for drug acquisition and treating IRF were derived using published data and applied to compare caspofungin with liposomal amphotericin B. Sensitivity analyses were performed by varying the IRF and relative acquisition costs to assess the effect of these factors on the cost differences.

RESULTS

The acquisition costs per patient were 6942 dollars for liposomal amphotericin B and 3996 dollars for caspofungin. The estimated cost per patient from IRF was 3173 dollars for liposomal amphotericin B and 793 dollars for caspofungin. Combining drug acquisition and IRF costs, the overall treatment cost per patient for caspofungin was 5326 dollars less than for liposomal amphotericin B. In sensitivity analyses of drug costs, the price of liposomal amphotericin B would have to be 23.95 dollars per vial for the overall treatment costs to be equal.

CONCLUSION

Comparison of cost estimates derived from published data revealed that a combined estimate of acquisition costs and costs related to the treatment of IRF was lower for caspofungin than for liposomal amphotericin B for empirically treating patients with neutropenic fever.

New strategies of antifungal therapy in hematopoietic stem cell transplant recipients and patients with hematological malignancies

Invasive fungal infections (IFIs) are associated with considerable morbidity and mortality among high-risk individuals. Outcomes for IFI historically have been suboptimal and associated with a high mortality rate, hence global prophylaxis strategies have been applied to at-risk populations. Among certain populations, fluconazole prophylaxis has reduced systemic and superficial infections caused by Candida species. Newer azoles are currently being evaluated as prophylaxis and have the potential to provide protection against mould pathogens that are more troublesome to treat once they occur. Global prophylaxis strategies have the shortcoming of subjecting patients to therapy that ultimately will not need it. Targeted prophylaxis has the advantage of treating only patients at highest risk using some parameter of greater host susceptibility. Prophylaxis strategies are most suitable in patients at the highest risk for IFI. For patient groups whose risk is somewhat lower or when suspicion of IFI occurs in patients receiving prophylaxis, empirical antifungal therapy is often employed following a predefined period of fever. Again this approach subjects many non-infected patients to unnecessary and toxic therapy. A more refined approach such as presumptive or pre-emptive therapy whereby treatment is only initiated upon positive identification of a surrogate marker of infection in combination with clinical and radiological signs will subject fewer patients to toxic and expensive treatments.

Is combination antifungal therapy for invasive aspergillosis a necessity in hematopoietic stem-cell transplant recipients?

PURPOSE OF REVIEW

The use of combination antifungal therapy in hematopoietic stem-cell transplantation patients is controversial and limited by a paucity of controlled data. The recent literature is reviewed and the relative arguments for and against combination antifungal therapy are outlined with summative recommendations to assist practitioners in decision-making.

RECENT FINDINGS

There is an abundance of in-vitro and murine in-vivo combination antifungal literature, whereas clinical data are less abundant and controlled. Of the published case series there is a suggested benefit to combination therapy over monotherapy, although there are limitations to the available literature. Other issues in the combination debate that are addressed include the following: improved response rates and a survival advantage have been demonstrated in recent monotherapy studies; response rates in most published combination therapy studies do not suggest large gains over monotherapy; the lack of sustained survival advantage to combination therapy studies; and finally the consideration of host defenses in treatment responses.

SUMMARY

Based on available data, combination therapy is not warranted at the initial diagnosis of invasive aspergillosis. Randomized, controlled trials with rigorous study design are needed.

Drug interactions in the hematopoietic stem cell transplant (HSCT) recipient: what every transplanter needs to know

Pharmacokinetic drug interactions among hematopoietic stem cell transplant recipients can result in either increases in serum concentrations of medications, which may lead to enhanced toxicity; or reduced serum concentrations, which can lead to treatment failure and the emergence of post transplant complications. The use of drugs that have a narrow therapeutic index, such as cyclosporine/tacrolimus (calcineurin inhibitors), increases the significance of these interactions when they occur. This report will review the clinical data evaluating the drug interactions of relevance to HSCT clinical practice, focusing on the pharmacokinetic interactions, and provides recommendations for managing these interactions to avoid both toxicity and treatment failure.

Dose modification protocol using intravenous busulfan (Busulfex) and cyclophosphamide followed by autologous or allogeneic peripheral blood stem cell transplantation in patients with hematologic malignancies

We evaluated the safety and toxicity through a 5-cohort dose-modification model of once-daily administration of IV busulfan (Bu) in combination with high-dose cyclophosphamide (Cy) as preparative therapy for stem cell transplantation. Twenty-one adult patients with hematologic malignancies were evaluated. Eleven patients underwent autologous and 10 patients underwent HLA-matched sibling allogeneic transplantation. Patients were sequentially enrolled into 5 cohorts. Cohort 1 received intravenous (IV) Bu 1.6 mg/kg every 12 hours for 2 doses and then 0.8 mg/kg every 6 hours for 12 doses; cohort 2 received IV Bu 1.6 mg/kg every 12 hours for 4 doses and then 0.8 mg/kg every 6 hours for 8 doses; cohort 3 received IV Bu 3.2 mg/kg for 1 dose and then 1.6 mg/kg every 12 hours for 2 doses and 0.8 mg/kg every 6 hours for 8 doses; cohort 4 received IV Bu 3.2 mg/kg every 24 hours for 2 doses and then 0.8 mg/kg every 6 hours for 8 doses; and cohort 5 received IV Bu 3.2 mg/kg every 24 hours for 4 doses. In all groups, Bu was administered on day -7 through day -4 and was followed at least 6 hours after the last Bu dose by Cy 60 mg/kg daily for 2 doses on days -3 and -2. Blood samples were collected for pharmacokinetic analysis on the first and last day of IV Bu administration. All patients were alive and had engrafted at day 30. Five patients developed grade 3 or 4 toxicities. Four patients developed hepatic abnormalities, and 3 exhibited evidence of veno-occlusive disease. Two of 3 patients in cohort 5 with a Bu area under the curve >6000 micromol/min developed autopsy-confirmed veno-occlusive disease. Interpatient variability in AUCs was observed in patients within and between cohorts, but no statistically significant interpatient differences were observed in Bu half-life, volume of distribution, clearance, or dose-adjusted area under the curve. Further, minimal variability in Bu pharmacokinetics was observed between the 2 evaluations performed in each patient, thus reflecting the stability of Bu disposition within individual patients. On the basis of the dosing guidelines and schedule outlined in this study, our data suggest that administration of IV Bu 3.2 mg/kg IV every 24 hours for 4 doses in combination with Cy may result in excessive toxicity.

GM-CSF versus G-CSF: engraftment characteristics, resource utilization, and cost following autologous PBSC transplantation

BACKGROUND

G-CSF and GM-CSF have both been shown to decrease the time to hematopoietic recovery when administered after autologous BM or peripheral stem cell re-infusion. However, few studies have compared G-CSF and GM-CSF to determine which is the preferred myeloid growth factor.

METHODS

This study compares a prospectively accrued cohort of 22 patients receiving GM-CSF with a historical cohort of patients who received G-CSF commencing Day + 6 after autologous PBSC transplantation. Patients were matched based on disease type and stage, CD34(+) cell dose/kg, conditioning regimen, and prior treatment. Time to myeloid engraftment, growth factor utilization, antibiotic utilization, fever incidence, and cost were compared.

RESULTS

The median time to neutrophil and platelet engraftment was similar in the two groups (ANC > 500 /mm(3), GM-CSF 12 versus G-CSF 11, P = 0.69). There was a trend towards more days of temperature > 38.0 masculine C (six versus three, P = 0.05) and febrile neutropenia (three versus two, P = 0.06) in the GM-CSF arm. There was a trend towards increased use of i.v. antibiotics in the GM-CSF cohort (7.6 days versus 5.5 days, P = 0.06). More chest X-rays (1.5 versus 1.0, P = 0.03) were ordered, and more blood cultures drawn (4.2 versus 2.7, P = 0.05) as part of fever evaluation in the group treated with GM-CSF. Resource utilization based on actual wholesale pricing (AWP) favored the G-CSF cohort. Applying a sensitivity analysis, GM-CSF became cost-effective when priced below $94 per 250 micro g, despite greater resource utilization.

DISCUSSION

This study suggests that engraftment characteristics are similar with GM-CSF and G-CSF following PBSC transplantation. Resource utilization for fever treatment and evaluation may be greater with GM-CSF. Determination of which agent is more cost-effective depends on institutional acquisition costs.

Busulfan, cyclophosphamide, and etoposide as conditioning for autologous stem cell transplantation in multiple myeloma

Autologous stem cell transplantation (ASCT) has enabled the use of high-dose alkylating agents either as a single agent or in combination with other cytotoxic agents and/or total body irradiation (TBI) for the treatment of multiple myeloma. Despite improved complete remission rates, relapse and regimen-related toxicities remain challenging. In an effort to increase event-free survival and decrease the high incidence of regimen-related toxicity, we have studied the use of etoposide in combination with reduced-dose busulfan and cyclophosphamide as a conditioning regimen for ASCT in a group of 26 patients with advanced multiple myeloma. Median follow-up for the group was 30 months. There was no early treatment-related mortality. The main toxicity was mucositis. Otherwise, there was 1 case of reversible, clinically diagnosed hepatic veno-occlusive disease. Post-engraftment, 10 patients (38%) achieved CR, 15 (58%) patients achieved PR or SD, and 1 patient developed progressive disease (4%). Five patients in PR and 1 with progressive disease before transplant attained a CR post-transplant. The median times for event-free survival and overall survival after transplantation were 24 and 43 months, respectively. In conclusion, conditioning with busulfan, cyclophosphamide, and etoposide followed by ASCT is a safe regimen with comparable effectiveness to other previously used preparative regimens, thus providing another approach of non-TBI containing high-dose chemotherapy for patients with multiple myeloma.

Prophylaxis, empirical therapy, or pre-emptive therapy of fungal infections in immunocompromised patients: which is better for whom?

Immunocompromised patients are at risk of developing fungal infections. Over time, the incidence of fungal infections and the spectrum of causative organisms have changed. In addition, treatment strategies in this high-risk population have also changed. Traditional approaches (using polyene-based therapy and older azoles), including empirical treatment strategies, have evolved to include prophylaxis in populations at the greatest risk. These strategies, although effective against Candida species, have not really impacted infections caused by Aspergillus spp. With the recent approval of antifungal agents with demonstrated activity against Aspergillus and other mould infections, there is hope for better outcomes in the treatment of established infections. Several agents, with activity against Aspergillus, have been shown to be effective in the empirical setting. The role of these new antifungal agents in the prophylactic setting remains unknown at present, but the potential for reducing Aspergillus infections is promising and requires ongoing study. The other area of significant research in fungal infections has been the search for accurate, non-invasive, rapid diagnostic tests. Over the past year, several publications have indicated that early diagnosis is possible in immunocompromised patients. These new diagnostics have paved the way for a new strategy, called pre-emptive therapy, enabling infected patients to be identified at an earlier stage of infection. This strategy will permit targeted antifungal therapy in those at greatest risk, and will avoid unnecessary, potentially toxic therapy in those not infected. Validations of the various techniques show promise and are reviewed in this paper.

Evolution, incidence, and susceptibility of bacterial bloodstream isolates from 519 bone marrow transplant patients

Bacteria remain an important cause of infection in bone marrow transplants. To examine shifts in the etiology and susceptibility of bacterial isolates from transplants, we reviewed the incidence and susceptibility of blood isolates during a 7-year period. The infection rate fell dramatically during this time. Gram-positive organisms were isolated more often than gram-negative organisms, but the trend is reversing. Streptococci surpassed staphylococci for 5 years as the leading pathogen. Increasing resistance to penicillin, ciprofloxacin, and imipenem was noted in Streptococcus species. With the exception of type 1 beta-lactamase-producing bacteria and Pseudomonas aeruginosa, gram-negative isolates remained overall susceptible to ceftazidime. Increased antibiotic prophylaxis coincided with the reduction in percentage of infected patients and increase in resistance to beta-lactam antibiotics. Mortality attributed to bacteremia was low except for infections caused by P. aeruginosa and the Enterobacter, Serratia, Citrobacter group. There was no mortality attributable to gram-positive organisms such as Staphylococcus aureus and viridans streptococci.

Infections following hematopoietic stem cell transplantation

Numerous advances have been made in the management of infection in HSCT recipients. With increasing knowledge the authors are able to prevent several serious infections from occurring, and reduce the severity of infections once they occur. Despite these advances, several previously unrecognized pathogens have emerged and pose risks to this population. Ongoing surveillance and reporting of atypical infections are warranted. Transplant and infectious disease clinicians alike must be vigilant to the shifts in infectious syndromes as a consequence of various prophylaxis and preemptive strategies, and be ready to modify empiric strategies to meet the changing microbiologic milieu. As we increase our understanding of the HSCT process, and use the immune system rather than relying on high-dose chemotherapy, the authors are likely to reduce toxicities and improve patient outcomes.

Empiric antifungal therapy for the neutropenic patient

One of the major challenges facing oncologists today is invasive fungal infection. Difficult to diagnose and deadly when missed, invasive fungal infection--primarily by Candida and Aspergillus organisms--is the major infectious cause of death associated with chemotherapy-induced myelosuppression. In this review, the problem will be described and evidence-based approaches to management, including assessment for risk factors and empiric antifungal therapy, will be discussed. Finally, the future of diagnostic and therapeutic strategies for protecting the immunocompromised patient will be considered.

Clinical care for patients receiving autologous hematopoietic stem cell transplantation in the home setting

PURPOSE/OBJECTIVES

To undertake a pilot study of autologous hematopoietic stem cell transplantation (HSCT) in the patient's home to improve satisfaction of care, reduce financial costs, and relieve pressure on inpatient accommodation.

DESIGN

Descriptive, cross-sectional, qualitative.

SETTING

Patients' homes within the metropolitan area of Perth, Australia.

SAMPLE

25 Caucasian adults with recurrent multiple myeloma, non-Hodgkin's lymphoma, or Hodgkin's disease requiring autologous HSCT.

METHODS

A program was developed to use the bone marrow transplant team from a major tertiary hospital to permit home visiting, treatment with cytotoxic chemotherapy at home, treatment of complications at home, and an integrated home/hospital caring facility to expedite hospital admission if complications developed.

FINDINGS

The program was practical to administer, improved overall patient satisfaction, and was significantly less costly than inpatient transplantation. Fifteen patients (60%) of the total study group of 25 required hospital admission for a median of five days (range 1-13 days) for management of complications, predominantly febrile neutropenia. Nineteen (76%) of the 25 patients received i.v. antibiotic therapy at home during the period of neutropenia. Two patients died of transplant-related complications--one from respiratory syncytial virus infection and one from veno-occlusive disease of the liver. These complications were not attributable to the home setting.

IMPLICATIONS FOR NURSING PRACTICE

This program increased the responsibility and sense of autonomy of advanced practice nurses and developed their counseling skills as well as their ability to participate more actively in the decision-making process of those involved.

MAIN RESEARCH VARIABLES

Participation in the home transplant program, patient satisfaction, nursing development, and cost-effectiveness of the program.