Validation of a multivariable prediction model for post-engraftment invasive fungal disease in 465 adult allogeneic hematopoietic stem cell transplant recipients.

BACKGROUND: Recently, we reported a simple prognostic score for post-engraftment invasive fungal disease (IFD) obtained in 404 adult allogeneic hematopoietic stem cell transplant (alloSCT) (training cohort). OBJECTIVES: We aim to validate this score in an external cohort assessing the 1-year cumulative incidence (CI) of post-engraftment IFD. Additionally, we analyse the type of IFD and incidence of IFD according to type of prophylaxis. PATIENTS/METHODS: We included 465 consecutive adult recipients surviving >40 days who engrafted and were discharged without prior IFD (median age 45 years, range, 14-69). RESULTS: Patients classified as low-risk, 139; intermediate-risk, 162; and high-risk, 164 (35% vs 27% in the training cohort, P = 0.03). The CI of probable/proven IFD in the validation cohort was 8% vs 11% in the training cohort (P = 0.006). The only voriconazole prophylaxis used in the training cohort was 100 mg/12 h, 65% vs 27% in the validation cohort, but 38% received 200 mg/12 h. Thus, the validation cohort showed a lower CI of IFD (P = 0.009). The post-engraftment IFD score was validated, showing a CI of IFD for low-, intermediate- and high-risk of 3%, 6% and 14%, respectively (P < 0.001). CONCLUSION: To our knowledge, this is the first prognostic index to predict the occurrence of post-engraftment IFD after alloSCT that has been validated in an external cohort.

Clinical efficacy of ceftazidime/avibactam versus other active agents for the treatment of bacteremia due to carbapenemase-producing Enterobacteriaceae in hematologic patients.

OBJECTIVES: The primary objective was to describe clinical features, treatment and outcomes in patients with carbapenemase-producing Enterobacteriaceae (CPE) bacteremia. Additionally, patients treated with ceftazidime/avibactam (study group) were compared to the rest of the patients (comparator group) to determine the influence of the treatment in both crude mortality and clinical cure. METHODS: Multicenter and retrospective study that included patients with hematologic malignancies who had CPE bacteremia. A bivariate analysis was performed to compare the clinical variables between the study group and the control group. RESULTS: 31 patients were included. Bacteremia was considered primary in 14 (45%) patients. Overall crude mortality at 30days was 45.2% (n=14). Mortality was more frequent when septic shock (78.6% vs 11.8%; p>0.001) and higher Pitt score (6+14 vs 1.5+4; p<0.01) were present. 8 patients (25.8%) received treatment with ceftazidime/avibactam. No significant differences in crude mortality were found between study and comparator groups (p=0.19). In contrast, patients in study group had higher clinical cure rates than the comparator group within 14days of initiating treatment (85.7% vs. 34.8%, respectively, p=0.031). CONCLUSIONS: CPE bacteremia is associated with high mortality in patients with hematologic malignancies. Ceftazidime/avibactam may be an effective alternative for treating these patients.

Cytoplasmic localization of wild-type survivin is associated with constitutive activation of the PI3K/Akt signaling pathway and represents a favorable prognostic factor in patients with acute myeloid leukemia.

Survivin is over-expressed in most hematologic malignancies but the prognostic significance of the subcompartmental distribution of wild-type or splicing variants in acute myeloid leukemia has not been addressed yet. Using western blotting, we assessed the expression of wild-type survivin and survivin splice variants 2B and Delta-Ex3 in nuclear and cytoplasmic protein extracts in samples taken from 105 patients at the time of their diagnosis of acute myeloid leukemia. Given that survivin is a downstream effector of the PI3K/Akt signaling pathway, survivin expression was also correlated with pSer473-Akt. Wild-type survivin and the 2B splice variant were positive in 76.3% and 78.0% of samples in the nucleus, cytoplasm or both, whereas the Delta-Ex3 isoform was only positive in the nucleus in 37.7% of samples. Cytoplasmic localization of wild-type survivin was significantly associated with the presence of high levels of pSer473-Akt (P<0.001). Inhibition of the PI3K/Akt pathway with wortmannin and Ly294002 caused a significant reduction in the expression of cytoplasmic wild-type survivin. The presence of cytoplasmic wild-type survivin and pSer473-Akt was associated with a lower fraction of quiescent leukemia stem cells (P=0.02). The presence of cytoplasmic wild-type survivin and pSer473-Akt were favorable independent prognostic factors. Moreover, the activation of the PI3K/Akt pathway with expression of cytoplasmic wild-type survivin identified a subgroup of acute myeloid leukemia patients with an excellent outcome (overall survival rate of 60.0±21.9% and relapse-free survival of 63.0±13.5%). Our findings suggest that cytoplasmic wild-type survivin is a critical downstream effector of the PI3K/Akt pathway leading to more chemosensitive cells and a more favorable outcome in acute myeloid leukemia.