Jörg J. Vehreschild

Patients at High Risk of Invasive Fungal Infections When and How to Treat

When and how to treat invasive fungal infections (IFIs) is discussed in this review, with a focus on the two most prevalent non-endemic IFIs, namely invasive aspergillosis and invasive candidiasis. Early treatment initiation in patients with IFIs has a profound impact on mortality rates, but reliable diagnostic measures are lacking. This situation has led to the parallel use of different treatment strategies, e.g. prophylaxis, empirical and pre-emptive treatment, as well as targeted treatment in response to a definite diagnosis of IFI. Identifying high-risk patients is the first step in reducing IFI-related mortality. Patients at risk of invasive aspergillosis comprise (i) those with acute myelogenous leukaemia (AML) or myelodysplastic syndrome (MDS) during remission induction chemotherapy; (ii) patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT); (iii) recipients of solid organ transplants; and (iv) those with other conditions of severe and prolonged immunosuppression. Patients at high risk of invasive candidiasis are less well defined. Risk factors are diverse and include haematological malignancy, neutropenia, age <1 month or >65 years, and recent abdominal surgery. The individual risk further depends on the presence of a variety of other risk factors, including central venous catheters, use of broad spectrum antibacterials, prolonged intensive care unit (ICU) stay, total parenteral nutrition, mucosal Candida spp. colonization and renal failure.Extensive research has been conducted to facilitate the best possible treatment strategies for these severe infections. Optimal timing and choice of antifungal agents largely remain a matter of controversy. After having reviewed the major clinical trials, we conclude that comparisons between different treatment strategies cannot be made, neither at present nor in the near future. The complexity of the clinical problem leads to an eclectic treatment approach to reduce morbidity and mortality from IFIs without compromising tolerability. We recommend prophylaxis with posaconazole for allogeneic HSCT recipients, patients receiving induction chemotherapy for AML or MDS, and those undergoing immunosuppressive therapy for graft-versus-host disease after allogeneic HSCT. For the empirical treatment of persistently febrile neutropenia, caspofungin is our first-and liposomal amphotericin B deoxycholate (LAmB) our second-line choice. Once a diagnosis of invasive aspergillosis has been established, voriconazole should be the preferred treatment option, with LAmB being an alternative. Fluconazole prophylaxis for invasive candidiasis should remain restricted to high-risk ICU patients. Once a diagnosis has been established, the drug of choice for adequate treatment depends largely on neutrophil count and haemodynamic stability. In non-neutropenic patients, an echinocandin should be considered the first-line treatment option, while patients with susceptible Candida spp. may be switched to fluconazole. In neutropenic patients, caspofungin or micafungin might be preferred to anidulafungin as first-line treatment. LAmB is a second-line treatment option in both settings.Early diagnosis of IFIs is imperative to facilitate treatment success. In all patients at risk for IFIs, blood cultures, galactomannan antigen and diagnostic imaging should be rigorously enforced.

Forty-one recent cases of invasive zygomycosis from a global clinical registry

BACKGROUND Invasive zygomycosis accounts for a significant proportion of all invasive fungal diseases (IFD), but clinical data on the clinical course and treatment response are limited. PATIENTS AND METHODS Fungiscope-A Global Rare Fungal Infection Registry is an international university-based case registry that collects data of patients with rare IFD, using a web-based electronic case form at www.fungiscope.net. RESULTS Forty-one patients with invasive zygomycosis from central Europe and Asia were registered. The most common underlying conditions were malignancies (n = 26; 63.4%), diabetes mellitus (n = 7; 17.1%) and solid organ transplantation (n = 4; 9.8%). Diagnosis was made by culture in 28 patients (68.3%) and by histology in 26 patients (63.4%). The main sites of infection were the lungs (n = 24; 58.5%), soft tissues (n = 8; 19.5%), rhino-sinu-orbital region (n = 8; 19.5%) and brain (n = 6; 14.6%). Disseminated infection of more than one non-contiguous site was seen in six patients (14.6%). Mycocladus corymbifer was the most frequently identified species (n = 10, 24.4%). A favourable response was observed in 23 patients (56.1%). Overall survival was 51.2% (n = 21). At diagnosis, four patients (9.8%) were on continuous antifungal prophylaxis with itraconazole (n = 1; 2.4%) or posaconazole (n = 3; 7.3%). Initial targeted treatment with activity against zygomycetes was administered to 34 patients (82.9%). Liposomal amphotericin B was associated with improved response (P = 0.012) and survival rates (P = 0.004). CONCLUSIONS Pathogen distribution and, consequently, drug susceptibility seem to vary across different geographic regions. Furthermore, protection from invasive zygomycosis for patients on posaconazole prophylaxis is not absolute. Our findings indicate that the use of liposomal amphotericin B as first-line treatment for patients diagnosed with zygomycoses merits further investigation, preferably in the form of a clinical trial.

Clinical effectiveness of posaconazole prophylaxis in patients with acute myelogenous leukaemia (AML): a 6 year experience of the Cologne AML cohort

BACKGROUND Large randomized controlled trials have shown significant decreases in morbidity and mortality in leukaemia patients with posaconazole prophylaxis. However, the value of prophylaxis has been questioned in centres with a low incidence of invasive fungal diseases (IFDs) and pre-emptive treatment strategies. METHODS We prospectively evaluated the epidemiology of IFDs in acute myelogenous leukaemia (AML) patients undergoing first remission-induction chemotherapy before and after posaconazole prophylaxis had been introduced as a standard of care. Patients admitted from January 2003 to December 2005 received topical polyenes as antifungal prophylaxis (first group), while those admitted between January 2006 and December 2008 received 200 mg of oral posaconazole three times daily (second group). Other diagnostic and therapeutic standard operating procedures remained unchanged. RESULTS A total of 82 patients in the polyene prophylaxis group and 77 in the posaconazole prophylaxis group were included in the final analysis. Baseline characteristics were well matched between groups. Patients receiving topical polyene prophylaxis were more likely to experience breakthrough IFDs (19.5% and 3.9%; P = 0.003) or breakthrough aspergillosis (13.4% and 2.6%; P = 0.018) than patients receiving systemic posaconazole prophylaxis. They also had more febrile days (mean 10.7 +/- 9.66 and 7.3 +/- 5.73; P = 0.007), longer need for inpatient treatment (mean 53.0 +/- 24.16 and 46.0 +/- 14.39; P = 0.026) and a shorter fungal-free survival (78.7 and 90.4 days; P = 0.024). No significant differences were observed for persistent fever, pneumonia, lung infiltrates indicative of invasive pulmonary aspergillosis, or attributable and overall mortality. CONCLUSIONS After introduction of posaconazole prophylaxis for patients with AML, the number of febrile days, the incidence rate of IFDs and aspergillosis and the duration of hospitalization decreased significantly.

Therapy with antifungals decreases the diagnostic performance of PCR for diagnosing invasive aspergillosis in bronchoalveolar lavage samples of patients with haematological malignancies

OBJECTIVES Invasive aspergillosis (IA) is a life-threatening infection in severely immunocompromised patients, especially those receiving intensive chemotherapy or undergoing haematopoietic stem cell transplantation. As the clinical diagnosis of IA is mostly based on biomarkers (galactomannan, β-d-glucan, PCR assays) indicating Aspergillus as the underlying pathogen, the effect of antifungal treatment on the performance of these parameters is still controversial. We evaluated the effect of antifungal treatment on the performance of an Aspergillus-specific PCR assay in bronchoalveolar lavage (BAL) samples. PATIENTS AND METHODS Two-hundred-and-twenty-six BAL samples from 226 patients with haematological malignancies at high risk for IA classified according to the 2008 European Organization for the Research and Treatment of Cancer criteria were analysed retrospectively for the diagnostic performance of a nested Aspergillus PCR assay in relation to the number and type of mould-active antifungals received prior to BAL sampling. RESULTS Sensitivity of BAL PCR for patients without antifungal treatment prior to BAL sampling was 0.69, whereas specificity was 0.87. While no significant change in diagnostic performance by the addition of one antifungal was observed, receiving two or more antifungals prior to BAL sampling led to a significant decrease in the diagnostic performance of BAL PCR testing (P < 0.009). CONCLUSIONS Treatment with mould-active antifungals prior to BAL sampling significantly decreases the performance of the Aspergillus PCR assay in haematological patients if BAL was performed after administration of more than one antifungal agent. Performing BAL sampling for Aspergillus PCR diagnostic despite pre-treatment with one antifungal or while on prophylaxis is feasible.

Quantitation of azoles and echinocandins in compartments of peripheral blood by liquid chromatography-tandem mass spectrometry.

ABSTRACT A rapid turnaround is a prerequisite of therapeutic drug monitoring (TDM). For antifungals, this need is still unmet, since hardly any method has been established to simultaneously quantitate concentrations of different antifungal classes. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed allowing quantitation of anidulafungin (ANF), caspofungin (CSF), isavuconazole (ISC), micafungin (MCF), posaconazole (PSC), and voriconazole (VRC). Quantitation was successful with diluted plasma samples, peripheral blood mononuclear cells (PBMC), polymorphonuclear leukocytes (PMN), and erythrocytes (RBC). A triple quadrupole mass spectrometer in selected reaction monitoring mode was used with positive electrospray ionization. Cells and calibration standards were extracted with acetonitrile containing internal standard. Internal standards were a CSF derivate for echinocandins and itraconazole for triazoles. Chromatographic separation of the supernatant was achieved by a gradient method facilitating a BetaBasic C4 column. Analytes were quantified in a single 8-min run. Calibration curves were linear and fitted using least squares with a weighting factor of the reciprocal concentration. Limits of detection (ng/ml) were ANF, 8.3; CSF, 31.5; ISC, 1.5; MCF, 97.7; PSC, 3.3; and VRC, 1.4. The lower limits of quantitation (ng/ml) were ANF, 64; CSF, 108; ISC, 4.5; MCF, 160; PSC, 10; and VRC, 4.2. Intraday precisions ranged from 6.3% to 8.8% for azoles and 8.8% to 15.4% for echinocandins. Intraday and interday accuracies (percent bias) of all analytes were within 13.8%. The method was established as standard practice for the quantitation of intracellular antifungal concentrations and optimizes TDM by applying a rapid single method for 6 antifungals.

Diagnosing pulmonary aspergillosis in patients with hematological malignancies: a multicenter prospective evaluation of an Aspergillus PCR assay and a galactomannan ELISA in bronchoalveolar lavage samples

Diagnosing invasive pulmonary aspergillosis (IPA) remains a challenge in patients with hematological malignancies. The clinical significance of testing bronchoalveolar lavage (BAL) samples both with polymerase chain reaction (PCR) and Aspergillus galactomannan ELISA (GM) is unclear, and the BAL cutoff for GM has not been clearly evaluated yet.

Posaconazole concentrations in the central nervous system

more susceptible to the killing activity of caspofungin. This study is the first comparing caspofungin killing activity against the closely related species C. parapsilosis, C. orthopsilosis and C. metapsilosis. Killing curves, regardless of the medium used, showed a decreasing order of susceptibility to caspofungin: C. metapsilosis . C. orthopsilosis . C. parapsilosis. Based on high echinocandin MICs for C. parapsilosis sensu stricto, in the case of isolates identified as C. parapsilosis sensu lato low MICs of echinocandins may be regarded as an indicator that an isolate is in fact C. orthopsilosis or C. metapsilosis; in the case of isolates with low echinocandin MICs, DNA-based identification – 3 of the isolates is desirable. Because C. orthopsilosis and C. metapsilosis seem to be relevant species among bloodstream isolates in some countries, this distinction may be particularly important in some epidemiological situations or in clinical situations when the use of echinocandins as therapy or prophylaxis is planned.

Combined antifungal approach for the treatment of invasive mucormycosis in patients with hematologic diseases: a report from the SEIFEM and FUNGISCOPE registries.

Invasive mucormycosis (IM) in patients with acute leukemia and allogeneic stem cell transplant (allo-SCT) recipients treated with antifungal monotherapy is associated with high mortality rates of 44–49%.[1][1]–[3][2] Among the available antifungals, amphotericin B (AmB) formulations and

Phase II Dose Escalation Study of Caspofungin for Invasive Aspergillosis

ABSTRACT Our objective was to evaluate the maximum tolerated dose of caspofungin for invasive aspergillosis (IA). The safety and pharmacokinetics of escalating dosages of caspofungin were investigated in IA. Eight patients each received caspofungin 70, 100, 150, or 200 mg once a day (QD). Dose-limiting toxicity (DLT) was defined as the same non-hematological treatment-related adverse event of grade ≥4 in 2 of 8 patients or ≥3 in 4 of 8 patients in a cohort. A total of 46 patients (median age, 61 years; 21 female; 89% with hematological malignancies) received caspofungin (9, 8, 9, and 20 patients in the 70-, 100-, 150-, and 200-mg cohorts) for a median of 24.5 days. Plasma pharmacokinetics were linear across the investigated dosages and followed a two-compartment model, with weight as the covariate on clearance and sex as the covariate on central volume of distribution. Simulated peak plasma concentrations at steady state ranged from 14.2 to 40.6 mg/liter (28%), trough concentrations from 4.1 to 11.8 mg/liter (58%), and area under the concentration-time curve from 175 to 500 mg/liter/h (32%) (geometric mean, geometric coefficient of variation). Treatment was well tolerated without dose-limiting toxicity. The rate of complete or partial responses was 54.3%, and the overall mortality at 12-week follow-up was 28.3%. In first-line treatment of invasive aspergillosis, daily doses of up to 200 mg caspofungin were well tolerated and the maximum tolerated dose was not reached. Pharmacokinetics was linear. Response rates were similar to those previously reported for voriconazole and liposomal amphotericin.

Current experience in treating invasive zygomycosis with posaconazole

The treatment of zygomycosis has two cornerstones, namely, surgery and antifungal drugs. In many patients, both need to be applied to achieve treatment success; without treatment, the mortality rate of zygomycosis approaches 100%. Because treatment options are limited, no well-designed randomized clinical trial has been conducted and data are predominantly derived from compassionate-use programmes or case reports. Amphotericin B (AmB) lipid complex (ABLC) was clinically evaluated for efficacy against zygomycosis in a single series and resulted in cure or improvement in 52% and in the stabilizing of disease in 20% of patients. Liposomal AmB (L-AmB) is frequently used, but no large series have yet been published. Posaconazole has demonstrated in vitro and in vivo activity against Zygomycetes. Two series demonstrated salvage treatment response rates of 60% and 79%, respectively. Antifungal combinations have not been evaluated thoroughly enough to warrant recommendations outside of clinical trials. Survival is usually associated with surgical debridement and improvement in underlying diseases. Currently, surgical debridement should be performed. Antifungal treatment should consist of either ABLC > or =5 mg/kg once per day or L-AmB > or =3 mg/kg once per day. When toxicity occurs or stable fungal disease is achieved, treatment can be switched to oral posaconazole 200 mg four times per day. If impaired kidney function is overt or expected on the grounds of, for example, uncontrolled diabetes, primary treatment of zygomycosis with posaconazole is an option.