Empiric antifungal therapy in neutropenic cancer patients

Diagnostic-driven antifungal therapy in neutropenic patients using the D-index and serial serum galactomannan testing

Introduction

Invasive mold disease is an important complication of patients with hematologic malignancies, and is associated with high mortality. A diagnostic-driven approach has been an alternative to the classical empiric antifungal therapy. In the present study we tested an algorithm that incorporated risk stratification using the D-index, serial serum galactomannan and computed tomographic-scan to guide the decision to start antifungal therapy in neutropenic patients.

Patients and methods

Between May 2010 and August 2012, patients with acute leukemia in induction remission were prospectively monitored from day 1 of chemotherapy until discharge or death with the D-index and galactomannan. Patients were stratified in low, intermediate and high risk according to the D-index and an extensive workup for invasive mold disease was performed in case of positive galactomannan (≥0.5), persistent fever, or the appearance of clinical manifestations suggestive of invasive mold disease.

Results

Among 29 patients, 6 (21%), 11 (38%), and 12 (41%) were classified as high, intermediate, and low risk, respectively. Workup for invasive mold disease was undertaken in 67%, 73% and 58% (p = 0.77) of patients in each risk category, respectively, and antifungal therapy was given to 67%, 54.5%, and 17% (p = 0.07). Proven or probable invasive mold disease was diagnosed in 67%, 45.5%, and in none (p = 0.007) of high, intermediate, and low risk patients, respectively. All patients survived.

Conclusion

A risk stratification using D-index was a useful instrument to be incorporated in invasive mold disease diagnostic approach, resulting in a more comprehensive antifungal treatment strategy, and to guide an earlier start of treatment in afebrile patients under very high risk.

Pharmacoeconomic analysis of voriconazole vs. caspofungin in the empirical antifungal therapy of febrile neutropenia in Australia

In two major clinical trials, voriconazole and caspofungin were recommended as alternatives to liposomal amphotericin B for empirical use in febrile neutropenia. This study investigated the health economic impact of using voriconazole vs. caspofungin in patients with febrile neutropenia. A decision analytic model was developed to measure downstream consequences of empirical antifungal therapy. Clinical outcomes measured were success, breakthrough infection, persistent base-line infection, persistent fever, premature discontinuation and death. Treatment transition probabilities and patterns were directly derived from data in two relevant randomised controlled trials. Resource use was estimated using an expert clinical panel. Cost inputs were obtained from latest Australian sources. The analysis adopted the perspective of the Australian hospital system. The use of caspofungin led to a lower expected mean cost per patient than voriconazole (AU$40,558 vs. AU$41,356), with a net cost saving of AU$798 (1.9%) per patient. Results were most sensitive to the duration of therapy and the alternative therapy used post-discontinuation. In uncertainty analysis, the cost associated with caspofungin is less than that with voriconazole in 65.5% of cases. This is the first economic evaluation of voriconazole vs. caspofungin for empirical therapy. Caspofungin appears to have a higher probability of having cost-savings than voriconazole for empirical therapy. The difference between the two medications does not seem to be statistically significant however.

Index to Predict Invasive Mold Infection in High-Risk Neutropenic Patients Based on the Area Over the Neutrophil Curve

Purpose

Patients with prolonged and profound neutropenia are at high risk to develop invasive mold infections (IMIs). We developed an index (D-index) that combines duration and severity of neutropenia. The aim of this study was to test the D-index as a predictor of IMI.

Patients and Methods

The D-index was based on a graph plotting the absolute neutrophil counts during neutropenia and was the area over the neutrophil curve. We tested the D-index in 11 patients with acute myeloid leukemia (AML) who developed IMI during neutropenia and 33 AML patients without IMI (controls). We also calculated a cumulative D-index (c-D-index), defined as the cumulative D-index from the start of neutropenia until the date of the first clinical manifestation of IMI in patient cases. We compared the D-index and c-D-index with duration of neutropenia and defined a cutoff for IMI using the receiver operating characteristic (ROC) curve.

Results

The median duration of neutropenia and profound neutropenia of patient cases were significantly higher compared with controls (P = .002 and P = .001, respectively), as were the D-index (P < .001) and c-D-index (P = .02). The D-index and c-D-index performed better than duration of neutropenia in ROC curve analysis. For a cutoff point of 5,800 of the c-D-index, the sensitivity and specificity were 91% and 58%, respectively, and for a prevalence of IMI of 5%, 10%, and 15%, the negative predictive values were 99%, 98%, and 97%, respectively.

Conclusion

The high negative predictive value of the c-D-index may be of help in defining different risks for IMI in febrile neutropenic patients.

Economic impact of caspofungin as compared with liposomal amphotericin B for empirical therapy in febrile neutropenia in Australia

BACKGROUND

In a major clinical trial, caspofungin was as efficacious as liposomal amphotericin B (LAmB) for empirical therapy in febrile neutropenia. The current study sought to evaluate the economic impact of caspofungin as compared with LAmB for febrile neutropenia in Australia.

METHODS

A decision analytic model was developed to capture the downstream consequences of the empirical antifungal therapy. The main outcomes were success, breakthrough infection, persistent baseline infection, persistent fever, premature discontinuation and death. Underlying transition probabilities and treatment patterns were derived directly from trial data. Resource use was estimated using an expert panel. Cost inputs were obtained from the latest Australian representative sources. The perspective adopted was that of the Australian hospital system. Uncertainty and sensitivity analyses were undertaken via Monte Carlo simulation.

RESULTS

Caspofungin was associated with a net cost saving of AU$7245 (12.6%) per patient over LAmB (AU$50 267 versus AU$57 512). A similar trend was observed with cost per success and death prevented (AU$24 169 and AU$7270, respectively). Caspofungin dominated LAmB as it resulted in higher efficacy and lower costs when compared with LAmB. Persistent fever was the main contributing clinical outcome to the therapeutic costs of both antifungals. The results were most sensitive to therapy duration. Monte Carlo simulation suggested a 99.8% chance for LAmB to cost more than caspofungin.

CONCLUSIONS

This is the first economic study to evaluate the place of caspofungin as empirical therapy in Australia. Caspofungin is more cost-beneficial than LAmB, which contradicts the current Australian guidelines of recommending LAmB as the first choice for empirical therapy.

Invasive pulmonary aspergillosis: role of early diagnosis and surgical treatment in patients with acute leukemia

BACKGROUND

Aspergillus is a ubiquitous soil-dwelling fungus known to cause significant pulmonary infection in immunocompromised patients. The incidence of aspergillosis has increased during the past two decades and is a frequently lethal complication of acute leukemia patients that occurs following both chemotherapy and bone marrow transplantation. The diagnosis of invasive pulmonary aspergillosis (IPA) according to the criteria that are established by European Organization for the Research and Treatment of Cancer and Mycoses Study Group raise difficulties in severely ill patients. Despite established improvements in field of diagnosis (galactomannan antigen, quantitative PCR, real-time PCR for Aspergillus spp., and findings of computed tomography) and treatment with new antifungals, it is still a major problem in patients with acute leukemia. However, prompt and effective treatment of IPA is crucial because most patients will need subsequent chemotherapy for underlying hematologic disease as soon as possible.

CASE PRESENTATION

We report a 33-year-old male patient with acute promyelocytic leukemia diagnosed in 1993 that developed invasive pulmonary aspergillosis due to A. flavus at relapse in 2003. The patient was successfully treated with liposomal amphotericin B and underwent surgical pulmonary resection. The operative course was uneventful.

CONCLUSION

This report emphasizes the clinical picture, applicability of recent advances in diagnostic and therapeutic approaches for IPA. For early identification of a patient infected with IPA, a high index of suspicion and careful clinical and radiological examinations with serial screening for galactomannan should be established. If aspergillosis is suspected, anti-aspergillosis drug should be administered immediately, and if a unique pulmonary lesion remains, surgical resection should be considered to prevent reactivation during consecutive chemotherapy courses and to improve the outcome.

Invasive Fungal Infections in Patients with Acute Leukemia

Invasive fungal infections, a serious problem among cancer patients, are increasing in incidence, and can cause morbidity and mortality. Such infections may hinder additional treatment, especially for patients with leukemia. We report here our experiences in the management of invasive fungal infection in patients with acute leukemia. A total of 18 patients were enrolled in the study: 12 had microabscesses of the liver and/or spleen and/or kidneys; four had sinonasal infections; and two had pulmonary infections. Most of the patients (88.9%) received amphotericin B during treatment for fungal infection. Thirteen patients achieved complete response without evidence of fungal infection in follow-up. In the study, there were 11 mortalities, including five patients who died during therapy and six who later died as a result of relapse or refractoriness of the leukemia. We suggest that many patients may have a good response to antifungal therapy, and that fungal infection does not have to preclude additional chemotherapy after proper management. The state of the underlying disease has a strong impact on outcome.