Aki Tanihara

Antibiotic prophylaxis in hematopoietic stem cell transplantation. A meta-analysis of randomized controlled trials.

OBJECTIVES We performed a meta-analysis to evaluate the impact of systemic antibiotic prophylaxis in hematopoietic stem cell transplantation (HSCT) recipients. METHODS We collected reports from PubMed, the Cochrane Library, EMBASE, CINAHL, and Web of Science, along with references cited therein. We included prospective, randomized studies on systemic antibiotic prophylaxis in HSCT recipients. RESULTS Seventeen trials with 1453 autologous and allogeneic HSCT recipients were included. Systemic antibiotic prophylaxis was compared with placebo or no prophylaxis in 10 trials and with non-absorbable antibiotics in two trials. Systemic antibiotics other than fluoroquinolones were evaluated in five of these 12 trials. Four trials evaluated the effect of the addition of antibiotics for gram-positive bacteria to fluoroquinolones. One trial compared two different systemic antibiotic regimens: fluoroquinolones versus trimethoprim-sulfamethoxazole. As a result, systemic antibiotic prophylaxis reduced the incidence of febrile episodes (OR 0.16; 95%CI 0.09-0.30), clinically or microbiologically documented infection (OR 0.38; 95%CI 0.22-0.63) and bacteremia (OR 0.31; 95%CI 0.16-0.59) without significantly affecting all-cause mortality or infection-related mortality. CONCLUSIONS Systemic antibiotic prophylaxis successfully reduced the incidence of infection. However, there was no significant impact on mortality. The clinical benefits of prophylaxis with fluoroquinolones were inconclusive because of the small number of clinical trials evaluated.

Prophylactic role of long-term ultra-low-dose acyclovir for varicella zoster virus disease after allogeneic hematopoietic stem cell transplantation §

OBJECTIVES To evaluate the prophylactic role of long-term ultra-low-dose acyclovir for varicella zoster virus (VZV) disease after allogeneic hematopoietic stem cell transplantation (HSCT). METHODS We evaluated 141 patients who were planned to receive acyclovir at 200mg/day until the end of immunosuppressive therapy and for at least 1 year after HSCT in our center between June 2007 and June 2012. RESULTS The cumulative incidence of VZV disease after HSCT was 4.5% at 1 year and 18.3% at 2 years. Protocol violation was the only independent significant factor that increased the incidence of VZV disease (hazard ratio (HR) 7.50, 95% confidence interval (CI) 3.60-15.63). Excluding patients with protocol violation, the discontinuation of acyclovir was the only significant factor for the development of VZV disease (HR 5.90, 95% CI 1.56-22.37). Six patients experienced breakthrough VZV disease, but four of these six had not taken acyclovir for several weeks before breakthrough VZV disease. On the other hand, the cumulative incidence of VZV disease after the cessation of acyclovir was 28.4% at 1 year and 38.0% at 2 years. The proportion of disseminated VZV disease was only 7% and no patient died directly of VZV disease. CONCLUSIONS This study shows that long-term ultra-low-dose acyclovir appears to be effective for preventing VZV disease, especially disseminated VZV disease, after allogeneic HSCT. We recommend continuing acyclovir until the end of immunosuppressive therapy and for at least 1 year after HSCT, but additional strategies such as the administration of varicella vaccine may be needed to eradicate VZV disease.

The effect of different ATG preparations on immune recovery after allogeneic hematopoietic stem cell transplantation for severe aplastic anemia

Abstract Anti-thymocyte globulin (ATG) is widely used in the conditioning regimen before allogeneic stem cell transplantation for aplastic anemia. However, there are several different preparations of ATG and little is known about the difference of their effects on transplantation outcome. Therefore, in this study, we retrospectively compared the effect of two different rabbit ATG preparations [Thymoglobulin (ATG-G) and ATG-Fresenius (ATG-F)] on immune recovery and cytomegalovirus infection after transplantation. The conditioning regimen was a combination of fludarabine, cyclophosphamide, and ATG. Low dose total body irradiation was added in alternative donor transplantation. Four patients received ATG-F at 5 mg/kg/day from day −7 to day −3, whereas ATG-G was given at 2·5 mg/kg/day from day −5 to day −2 in three patients. There was no graft rejection and no grade II–IV acute graft-versus-host disease. All three patients in the ATG-G group developed positive cytomegalovirus antigenemia including two with high-grade antigenemia, whereas two of the four patients in the ATG-F group were persistently negative. Immunological evaluation on day 60 revealed that both CD4+ and CD8+ T-cell recoveries were delayed in the ATG-G group. These findings suggested that ATG-G has a stronger immunosuppressive activity than the ATG-F with a dose ratio of 1:2·5.

Low-dose acyclovir prophylaxis for the prevention of herpes simplex virus disease after allogeneic hematopoietic stem cell transplantation

Currently, acyclovir (ACV) at 1000 mg/day is widely used as prophylaxis in the early phase of hematopoietic stem cell transplant (HSCT) in Japan. However, low‐dose ACV (200 mg/day) has been shown to prevent varicella zoster virus reactivation in the middle and late phases of HSCT.

Prediction of transplant-related complications by C-reactive protein levels before hematopoietic SCT.

Various biomarkers have been investigated with regard to their ability to predict the outcome of allogeneic hematopoietic SCT (HSCT). In this study, we retrospectively reviewed 90 recipients who received HSCT between 2007 and 2011 in our institution, and evaluated the predictive value of the baseline serum C-reactive protein (CRP) levels just before the initiation of conditioning for transplant-related complications after allogeneic HSCT. A receiver-operating characteristic curve revealed that the baseline serum CRP levels had an excellent predictive value for non-relapse mortality (NRM), with an area under the curve of 0.83. The sensitivity and specificity for NRM were 80% and 87%, respectively, with a cutoff of 0.6 mg/dL. With this cutoff value, multivariate analyses revealed that a higher baseline CRP level was an independent risk factor for NRM (HR 6.21, P<0.01), grade III–IV acute GVHD (HR 3.91, P=0.03) and poor overall survival (HR 3.27, P=0.0018). On the other hand, the baseline CRP level did not predict infectious events. These findings suggested that CRP levels before conditioning may be a useful predictive biomarker for poor survival.

Pharmacokinetics of CsA during the switch from continuous intravenous infusion to oral administration after allogeneic hematopoietic stem cell transplantation.

We investigated the serial changes in the blood CsA concentration during the switch from continuous intravenous infusion to twice-daily oral administration in allogeneic hematopoietic stem cell transplant recipients (n=12). The microemulsion form of CsA, Neoral, was started at twice the last dose in intravenous infusion in two equally divided doses. The area under the concentration–time curve during oral administration (AUCPO) was significantly higher than the AUC during intravenous infusion (AUCIV) (median 7508 vs 6705 ng/ml × h, P=0.050). The median bioavailability of Neoral, defined as (AUCPO/DOSEPO) divided by (AUCIV/DOSEIV), was 0.685 (range, 0.45–1.04). Concomitant administration of oral voriconazole (n=4) significantly increased the bioavailability of Neoral (median 0.87 vs 0.54, P=0.017), probably due to the inhibition of gut CYP3A4 by voriconazole. Although the conversion from intravenous to oral administration of CsA at a ratio of 1:2 seemed to be appropriate in most patients, a lower conversion ratio may be better in patients taking oral voriconazole. To obtain a similar AUC, the target trough concentrations during twice-daily oral administration should be halved compared with the target concentration during continuous infusion.

Clinical outcome in patients with small intestinal non-Hodgkin lymphoma

The clinical features and outcome of small intestinal lymphoma remain unclear. We retrospectively analyzed 23 patients who had non-Hodgkin lymphoma with a small intestinal lesion. With a median follow-up of 37 months, the 5-year overall survival and failure-free survival (FFS) were 64% and 60%, respectively. In a univariate analysis, a worse performance status at the start of treatment and the occurrence of abdominal symptoms or perforation during treatment were associated with poor survival. Perforation often resulted in a dismal prognosis in patients with uncontrollable lymphoma, but not in patients with lymphoma in remission. The role of surgery in small intestinal lymphoma remains equivocal. In the current study, surgery before other therapies favorably influenced FFS, and all patients who underwent complete resection of the small intestinal lesion had extremely favorable results. Further studies are warranted to establish optimal therapeutic strategies.

Retrospective Evaluation of the Area Over the Neutrophil Curve Index to Predict Early Infection in Hematopoietic Stem Cell Transplantation Recipients

We investigated the impact of neutropenia on the development of early bloodstream and pulmonary infections in hematopoietic stem cell transplantation (HSCT) recipients, and evaluated the utility of an index (D-index) that reflects both the intensity and duration of neutropenia. Fifty-eight patients (23 autologous, 35 allogeneic HSCT recipients) were enrolled in this retrospective study. The D-index was defined as the area over the neutrophil curve during neutropenia. We also evaluated the utility of the cumulative D-index from the start of neutropenia until the development of infection (c-D-index), which may enable real-time assessment of the risk for infection. The patients showed 12 and 7 episodes of bloodstream and pulmonary infection, respectively. The D-index, days of neutropenia (<500/microL) and days of profound neutropenia (<100/microL) had at least a nearly significant impact on the development of both bloodstream and pulmonary infections. On the other hand, the c-D-index, cumulative days of neutropenia, and cumulative days of profound neutropenia significantly affected pulmonary infection, but not bloodstream infection. The c-D-index had a high negative predictive value of 97.4% for pulmonary infection with a cutoff of 5500, but the area under the receiver operating characteristic curve was similar to that of the cumulative days of neutropenia and profound neutropenia. Our results showed that although the c-D-index may be useful for identifying patients who are at low risk for early pulmonary infection after HSCT, its performance was similar to that of the simple duration of neutropenia.

Fludarabine, cyclophosphamide, anti-thymocyteglobulin, and low-dose total body irradiation conditioning enables 1-HLA-locus-mismatched hematopoietic stem cell transplantation for very severe aplastic anemia without affecting ovarian function

Allogeneic hematopoietic stem cell transplantation for severe aplastic anemia from an alternative donor is associated with higher risks of graft rejection and severe graft‐versus‐host disease. We developed a conditioning regimen consisting of rabbit anti‐thymocyte globulin, fludarabine, cyclophosphamide, and low‐dose total body irradiation. Two adult female patients with transfusion‐dependent very severe aplastic anemia underwent 1‐locus mismatched transplantation using this regimen. Both patients achieved stable engraftment and the clinical course thereafter was uneventful with persistently normal ovarian function. This novel conditioning regimen may be suitable for alternative donor transplantation for severe aplastic anemia, especially in young female patients. Am. J. Hematol. 2009.

A randomized controlled trial of cyclosporine and tacrolimus with strict control of blood concentrations after unrelated bone marrow transplantation

Previous studies have suggested that tacrolimus (TAC) is more potent than cyclosporine (CSA) for prophylaxis against acute GVHD after allogeneic hematopoietic stem cell transplantation (HSCT). However, the target blood concentrations of these drugs in these studies were not consistent with the current recommendations. Therefore, we performed a randomized controlled trial to compare CSA and TAC with target blood concentrations of 500 and 15 ng/ml, respectively, to prevent acute GVHD after unrelated HSCT. A total of 107 patients were randomized into a CSA group (n=53) or a TAC group (n=54). During the first 4 weeks after HSCT, more than 90% of the patients achieved a mean blood concentration of between 80 and 120% of the target concentration. The incidences of grade II–IV and grade III–IV acute GVHD were 39.6 and 7.5% for the CSA group and 33.3 and 9.4% for the TAC group, respectively (P=0.41 and P=0.76). Other clinical outcomes, including overall survival, disease-free survival and the incidences of relapse, non-relapse mortality, and organ toxicities, were also equivalent. We concluded that the combinations of CSA and TAC with strict dose adjustment showed similar efficacies and toxicities as prophylaxis against acute GVHD after unrelated HSCT.