Akiko Yoneyama

Effect of fluconazole prophylaxis on fungal blood cultures: an autopsy-based study involving 720 patients with haematological malignancy

Summary. To investigate the utility of blood culture of invasive fungal infections in patients with haematological malignancies, an autopsy survey was conducted in 720 patients who were treated between 1980 and 1999. We identified 252 patients with invasive mycosis. These included Candida (n = 94), Aspergillus (n = 91), Zygomycetes (n = 34), Cryptococcus (n = 7), Trichosporon (n = 11), Fusarium (n = 1), and unknown fungi (n = 20). Of the 94 patients with invasive candidiasis, 20 had positive blood cultures. Of the 11 patients with invasive trichosporonosis, seven had positive blood cultures. The sensitivities of blood cultures were 1·1%, 0% and 14% for detecting invasive aspergillosis, zygomycosis and cryptococcosis respectively. Multiple regression analysis showed a significant correlation between results of Candida blood cultures and some variables, including prophylactic use of absorbable antifungals (P = 0·0181) and infection by Candida albicans (P = 0·0086). The sensitivity of blood cultures decreased when patients received antifungal chemoprophylaxis. Unless these agents are inactivated in culture bottles, conventional blood cultures might produce false‐negative results.

Umbilical Cord Blood Transplantation after Reduced-Intensity Conditioning for Elderly Patients with Hematologic Diseases

Although allogeneic hematopoietic stem cell transplantation is a potentially curative approach for advanced hematologic diseases, its application to elderly people is limited because of their comorbid physical conditions and lower chance of finding suitable related donors. Umbilical cord blood transplantation with reduced-intensity pretransplant conditioning (RI-UCBT) is 1 way to avoid these obstacles. We analyzed elderly patients aged 55 years and older with hematologic diseases who underwent RI-UCBT at our institute to assess feasibility and effectiveness of this treatment approach. Among the 70 patients included, 50 died, 74% of them from nonrelapse causes. Infection was the primary cause of death. Estimated overall survival and progression-free survival at 2 years were both 23%. In multivariate analyses, standard-risk diseases, age younger than 61 years, grade 0-II acute graft-versus-host disease, and the absence of preengraftment immune reaction were significantly associated with better overall survival. RI-UCBT is a potentially curative and applicable approach for elderly patients. Higher mortality, especially from nonrelapse causes, is the biggest problem to be solved to increase the feasibility of this approach.

Multicenter Study To Evaluate Bloodstream Infection by Helicobacter cinaedi in Japan

ABSTRACT Helicobacter cinaedi has being recognized as an important human pathogen which causes bloodstream infections. Although the first case of bacteremia with this pathogen in Japan was reported in 2003, the true prevalence of H. cinaedi as a pathogen of bloodstream infections in this country is not yet known. Therefore, the aim of our study was to assess the incidence of bacteremia with H. cinaedi in Japan. We conducted a prospective, multicenter analysis in 13 hospitals during 6 months in Tokyo, Japan. Among positive blood cultures from 1 October 2003 to 31 March 2004, isolates suspected of being Helicobacter species were studied for further microbial identification. Identification of the organisms was based on their biochemical traits and the results of molecular analysis of their 16S rRNA gene sequences. A total of 16,743 blood culture samples were obtained during the study period, and 2,718 samples (17.7%) yielded positive culture results for coagulase-negative staphylococci. Among nine isolates suspected to be Helicobacter species, six isolates were finally identified as H. cinaedi. The positivity rate for H. cinaedi in blood culture was 0.06% of total blood samples and 0.22% of blood samples with any positive culture results. All patients with bacteremia with H. cinaedi were found to have no human immunodeficiency virus (HIV) infection, but many of them had complications with either malignancy, renal failure, or a history of surgical operation. Therefore, our results suggest that bacteremia with H. cinaedi is rare but can occur in compromised hosts other than those with HIV infection in Japan.

High incidence of haemophagocytic syndrome following umbilical cord blood transplantation for adults

Umbilical cord blood transplantation (CBT) is widely accepted, but one critical issue for adult patients is a low engraftment rate, of which one cause is haemophagocytic syndrome (HPS). We aimed to identify the contribution of HPS to engraftment failure after CBT, following preparative regimens containing fludarabine phosphate, in 119 patients (median age, 55 years; range; 17–69 years) with haematological diseases. Graft‐versus‐host disease prophylaxis comprised continuous infusion of a calcineurin inhibitor with or without mycophenolate mofetil. Of the 119 patients, 20 developed HPS within a median of 15 d (cumulative incidence; 16·8%) and 17 of them did so before engraftment. Donor‐dominant chimaerism was confirmed in 16 of 18 evaluable patients with HPS. Despite aggressive interventions including corticosteroid, ciclosporin, high‐dose immunoglobulin and/or etoposide, engraftment failed in 14 of 18 patients. Of these 14 patients, four received second rescue transplantation and all resulted in successful engraftment. Overall survival rates significantly differed between patients with and without HPS (15·0% vs. 35·4%; P < 0·01). Univariate and multivariate analysis identified having fewer infused CD34+ cells as a significant risk factor for the development of HPS (P = 0·01 and 0·006, respectively). We concluded that engraftment failure closely correlated with HPS in our cohort, which negatively impacted overall survival after CBT.

Clinical Characteristics of Bacteremia Caused by Helicobacter cinaedi and Time Required for Blood Cultures To Become Positive

ABSTRACT The aim of this study was to clarify the clinical characteristics of patients with Helicobacter cinaedi bacteremia and the time required for blood cultures to become positive. The medical records of all patients with H. cinaedi bacteremia at Toranomon Hospital and Toranomon Hospital Kajigaya between March 2009 and March 2013 were retrospectively reviewed. Sixty-three patients, 34 men and 29 women with a median age of 67 years (range, 37 to 88 years), were diagnosed with H. cinaedi bacteremia. A total of 51,272 sets of blood cultures were obtained during the study period, of which 5,769 sets of blood cultures were positive for some organism and 126 sets were H. cinaedi positive. The time required for blood cultures to become positive for H. cinaedi was ≤5 days in 69 sets (55%) and >5 days in 57 sets (45%). Most patients had an underlying disease, including chronic kidney disease (21 cases), solid tumor (19 cases), hematological malignancy (13 cases), diabetes mellitus (8 cases), chronic liver disease (6 cases), and postorthopedic surgery (3 cases). Only 1 patient had no apparent underlying disease. The clinical symptoms included cellulitis in 24 cases, colitis in 7 cases, and fever only in 27 cases, including 7 cases of febrile neutropenia. The 30-day mortality rate of H. cinaedi bacteremia was 6.3%. In conclusion, most cases of H. cinaedi bacteremia occurred in immunocompromised patients. We might have overlooked nearly half of the H. cinaedi bacteremia cases if the duration of monitored blood culture samples had been within 5 days. Therefore, when clinicians suspect H. cinaedi bacteremia, the observation period for blood cultures should be extended.

Impact of HLA disparity in the graft-versus-host direction on engraftment in adult patients receiving reduced-intensity cord blood transplantation

Delayed engraftment or graft failure is one of the major complications after cord blood transplantation (CBT). To investigate factors impacting engraftment, we conducted a retrospective analysis of adult patients who underwent reduced-intensity CBT at our institute, in which preparative regimens mainly consisted of fludarabine, melphalan, and total body irradiation with graft-versus-host (GVH) disease prophylaxis using single calcineurin inhibitors. Among 152 evaluable patients, the cumulative incidence of neutrophil engraftment was 89%. High total nucleated cell and CD34(+) cell dose were associated with the faster speed and higher probability of engraftment. In addition, the degree of human leukocyte antigen (HLA) mismatch in the GVH direction was inversely associated with engraftment kinetics, whereas no statistically significant association was observed with the degree of HLA mismatch in the host-versus-graft direction. Similarly, the number of HLA class I antigens mismatched in the GVH direction, but not in the host-versus-graft direction, showed a negative correlation with engraftment kinetics. HLA disparity did not have significant impact on the development of GVH disease or survival. This result indicates the significant role of HLA disparity in the GVH direction in the successful engraftment, raising the novel mechanism responsible for graft failure in CBT.

Successful sustained engraftment after reduced-intensity umbilical cord blood transplantation for adult patients with severe aplastic anemia.

We retrospectively analyzed 12 consecutive adult severe aplastic anemia patients who received unrelated umbilical cord blood transplantation after a reduced-intensity conditioning regimen (RI-UCBT). The conditioning regimen consisted of 125 mg/m² fludarabine, 80 mg/m² melphalan, and 4 Gy of total body irradiation. The median infused total nucleated cell number and CD34(+) cell number were 2.50 × 10⁷/kg and 0.76 × 10⁵/kg, respectively. Eleven of the 12 patients achieved primary neutrophil and platelet engraftment. All patients who achieved engraftment had complete hematologic recovery with complete donor chimerism, except for one patient who developed late graft failure 3 years after RI-UCBT. Two of the 12 patients died of idiopathic pneumonia syndrome, and the remaining 10 patients are alive, having survived for a median of 36 months. Our encouraging results indicate that RI-UCBT may become a viable therapeutic option for adult severe aplastic anemia patients who lack suitable human leukocyte antigen-matched donors and fail immunosuppressive therapy.

In vitro Antiseptic Susceptibility of Clinical Isolates from Nosocomial Infections

To evaluate the susceptibility of a large number of strains to various antiseptics, we elaborated a simple, qualitative broth turbidity method in which we could quickly judge the efficacy visually. For this method, we prepared a modified neutralizer broth, consisting of trypticase soy broth containing 15% Tween 80, 1% soybean lecithin and 0.5% sodium thiosulfate. The susceptibilities of Serratia marcescens No. 26 to 4 antiseptics obtained from the turbidity method showed a good agreement with those obtained from the colony-counting method; the 4 antiseptics tested were povidone-iodine (PVP-I), chlorhexidine gluconate (CHG), benzalkonium chloride (BAC) and alkyldiaminoethylglycine hydrochloride (AEG). Both PVP-I and BAC had complete efficacy in 0.5 min against all isolates tested [100 isolates of S. marcescens, 103 of Klebsiella pneumoniae, 99 of Pseudomonas aeruginosa, 19 of Alcaligenes faecalis and 30 of A. xylosoxidans subsp. xylosoxydans (A. xylosoxydans)]. In contrast, the effectiveness of CHG was weak compared with PVP-I, BAC and AEG. Strong resistance against AEG was noted even after 3-min exposure in 1 isolate each of A. faecalis and A. xylosoxydans. It is concluded that the turbidity test is a simple and accurate method to evaluate susceptibility to various antiseptics and that it is suitable for a screening of a large number of strains. Among the 4 antiseptics tested, PVP-I and BAC showed a consistently high activity against all isolates, confirming PVP-I and BAC to be clinically useful antiseptics.

Mycophenolate and tacrolimus for graft-versus-host disease prophylaxis for elderly after cord blood transplantation: a matched pair comparison with tacrolimus alone.

Background. The optimal graft-versus-host disease (GVHD) prophylaxis after umbilical cord blood transplantation has not been established. Our previous observation using single calcineurin inhibitors revealed a high incidence and severity of early immune-mediated complications, especially for older patients or those with poor performance status. Methods. We conducted a single institute pilot study assessing the safety and effectiveness of mycophenolate mofetil (MMF) and tacrolimus (FK) combination as a GVHD prophylaxis for 29 patients (FK+MMF), and the results were compared with matched-pairs extracted from our historical database who received FK alone as GVHD prophylaxis (control). Results. FK+MMF group showed superior engraftment rate compared with control group (cumulative incidence until day 60 posttransplant; 90%±0% vs. 69%±1%, P=0.02). A cumulative incidence of severe type preengraftment immune reactions was significantly decreased in FK+MMF group (16%±1%) compared with that of control group (52%±2%, P=0.03), and, remarkably, there was no nonrelapse mortality (NRM) observed up to day 30 posttransplant in FK+MMF group, whereas 21%±1% of NRM was observed in the control group. However, the incidences of acute and chronic GVHD, estimated overall and progression-free survivals were comparable between two groups. Conclusions. MMF and FK in combination was well tolerated and decreased early NRM possibly by better control of preengraftment immune reactions. Subsequent NRM or disease progression needs to be overcome to further improve survival.

Increased levels of soluble CD8 and CD4 in patients with infectious mononucleosis.

Plasma levels of soluble CD8 (sCD8) and soluble CD4 (sCD4) in 44 patients with infectious mononucleosis (IM) were studied. A marked increase in sCD8 (22366 +/- 2702 U/ml; control: 219 +/- 10 U/ml; P < 0.0001) and significant increase in sCD4 (19.3 +/- 0.9; control: 8.1 +/- 0.2, P < 0.0001) strongly suggest activation of both CD8+ and CD4+ lymphocytes, which is important in restraining Epstein-Barr virus-infected B lymphocytes. Levels of sCD8 strongly correlated with the percentage and the absolute number of both CD8+ and CD8(+)-HLA-DR+ lymphocytes. In addition, we showed increased release of sCD8 from lymphocytes in vitro and increased ratio between plasma sCD8 and the number of CD8+ lymphocytes in blood, indicating that elevation of plasma sCD8 is due to expansion of CD8+ subset as well as increased sCD8 release from each CD8+ cell. Increased sCD4 release from CD4+ lymphocytes, the number of which is not increased in the blood during IM, was also seen. Patients with more severe fever had higher levels of sCD8 and sCD4. During convalescence sCD8 and sCD4 levels showed progressive decrease; however, even at 60-119 d after onset the levels of sCD8 and sCD4 remained higher than normal, suggesting prolonged lymphocyte activation. These results suggest that sCD8 and sCD4 are useful in monitoring immune activation during IM.