Reactivity of the 1,3-ß-D-glucan assay during bacteraemia: limited evidence from a prospective study.

There are discrepancies in the retrospective studies published in literature of whether or not bacteraemia could lead to false positivity of 1,3-ß-D (BG) glucan assay. We performed, for the first time, a prospective study evaluating the role of bacterial bloodstream infection to the reactivity of BG assay. Twenty-six episodes of bacteraemia that occurred in high-risk haematological patients were included in our study. Consecutive BG levels >80 pg ml(-1) were required for test positivity. Only 2 of 26 patients were BG positive - both with IFDs. Thus, we prospectively did not prove bacteraemia as the source of cross reactivity of BG assay in haematological patients.

Treatment of molecular relapse in patients with acute myeloid leukemia using clofarabine monotherapy.

Few studies have examined the treatment of molecular relapse in patients with acute myeloid leukemia (AML) using different treatment regimens. We describe for the first time in the literature experiences with administration of clofarabine monotherapy in the treatment of eight patients with AML with molecular relapse of the disease.

Monitoring trough voriconazole plasma concentrations in haematological patients: real life multicentre experience.

The objective of this retrospective study was to evaluate results from voriconazole therapeutic drug monitoring (TDM) in haematological patients in routine clinical practice. Between 2005 and 2010, 1228 blood samples were obtained from 264 haematological patients (median 3 samples/patient; range 1-27) receiving voriconazole for targeted/preemptive treatment of invasive aspergillosis (IA) (46.3% of samples), empirical therapy (12.9%) or prophylaxis (40.8%). A high-pressure liquid chromatography assay was used to analyse voriconazole concentrations. Clinical and laboratory data were analysed retrospectively. The median of the detected voriconazole plasma concentration was 1.00 µg ml(-1) (range <0.20-13.47 µg ml(-1)). Significant inter- and intra-patients variability of measured concentrations (81.9% and 50.5%) were identified. With the exception of omeprazole administration, there was no relevant relationship between measured voriconazole concentrations and drug dose, route administration, age, gender, CYP2C19*2 genotype, gastrointestinal tract abnormality, administration via nasogastric tube, serum creatinine, and liver enzymes. However, per patient analysis identified significant role of individual voriconazole dose and drug form change on measured plasma concentration. Measured voriconazole concentrations did not correlate with the treatment outcome of patients with IA. We only identified a limited number of adverse events related to voriconazole therapy; however, the median plasma concentration was not different from concentrations measured in samples without reported toxicity. Our retrospective study has suggested that routine monitoring of voriconazole plasma concentrations has probably only a limited role in daily haematological practice.

Micafungin as empirical antifungal therapy in hematological patients: a retrospective, multicenter study in the Czech and Slovak Republics.

The objective of this retrospective, multicenter study was to evaluate the efficacy and safety of micafungin as empirical antifungal therapy during febrile neutropenia (FN) in 73 hematological patients from six centers in two countries. All patients received 100 mg of micafungin/day. The overall favorable response rate (RR) was 64.8% when the resolution of fever during neutropenia was included in the response criteria and 84.5% when excluded. A significantly lower favorable RR in patients with persistent fever and non-specific pulmonary infiltrates compared to patients with persistent fever only (82.8 vs. 52.4%, respectively; p = 0.011) was not found when resolution of fever was not included in the composite endpoint criteria (93.1 vs. 78.6%, respectively; p = 0.180). Breakthrough fungal disease developed in 2.7% of patients. Treatment was discontinued in 16.4% of cases. Only one patient (1.4%) discontinued therapy due to an adverse event. Posaconazole prophylaxis improved favorable RR when defervescence was included as composite endpoint criterion (p = 0.047), but not when it was excluded (p = 0.485). However, neutrophil recovery did not influence favorable RR (p = 0.803 and p = 0.112, respectively). These data suggest that micafungin is safe and effective as an empirical therapy in patients with FN.

Difficulties in using 1,3-{beta}-D-glucan as the screening test for the early diagnosis of invasive fungal infections in patients with haematological malignancies--high frequency of false-positive results and their analysis.

We have evaluated the contribution of the 1,3-beta-d-glucan (BG) assay for the screening of invasive fungal infections (IFIs) in patients with haematological malignancies. Serum samples from patients at risk of IFI were collected twice a week and retrospectively tested using the BG assay. BG screening was performed on 1143 samples from 91 patients during 104 anticancer treatment cycles. Proven and probable cases of IFI occurred in 9 (8.7 %) treatment cycles. Depending on the criterion of positivity used (1x >60 pg ml(-1), 1x >80 pg ml(-1), 2x >60 pg ml(-1) or 2x >80 pg ml(-1)) the sensitivity and specificity were 89, 89, 67 and 44 %, and 20, 48, 33 and 56 %, respectively. Although the test was marked as positive in 82, 68, 54 and 45 % of all the treatment cycles, in the majority of cases, these positivities were probably false. The major limit of the BG test was an extremely low positive predictive value (10 to 12 %). We have analysed mucositis, candida colonization, bacteraemia, use of antimicrobials, erythrocyte and thrombocyte filtered blood products, collecting tubes or sampling via venous catheters. Even though no factor is a major source of BG, it could at least partially influence BG assay performance. Thus, BG detection has a limited usefulness as a screening method for IFIs in patients with haematological malignancies.