Kazunori Nakase

Fatal Trichosporon fungemia in patients with hematologic malignancies

Objective: Invasive Trichosporon infection has been increasingly recognized in patients with hematologic malignancies. Our study aims to clarify the clinical characteristics of this disease and factors influencing patient prognosis. Patients and methods: We retrospectively analyzed 33 cases of Trichosporon fungemia (TF) in patients with hematologic malignancies treated at our collaborating five hospitals in Japan between 1992 and 2007. Results: The majority of these patients had acute leukemia (82%), neutropenia (85%), and a history of intensive chemotherapy (91%). TF occurred as a breakthrough infection during antifungal therapy in 30 patients (91%), 18 of whom were receiving micafungin. The surveillance cultures of most patients were negative for Trichosporon. Only a few patients exhibited elevated levels of 1,3‐β‐d‐glucan before positive blood culture. Twenty‐five patients (76%) died of this infection. The resolution of infection was associated with neutrophil recovery (P = 0.0001), absence of hyperglycemia (P = 0.023), and azole inclusive therapy (P = 0.031). Survival was significantly longer in patients receiving antifungal therapies containing azole than in those who did not receive azole (P = 0.0034). Conclusions: At present, the diagnosis of invasive trichosporonosis depends on blood culture studies, and the mortality of this disease is high; however, azole therapy and control of blood glucose level, together with hematopoietic recovery could help in improving the clinical outcome. When we use antifungals lacking anti‐Trichosporon activity, sufficient care should be taken to prevent the development of breakthrough trichosporonosis.

Geographic heterogeneity of cellular characteristics of acute myeloid leukemia: a comparative study of Australian and Japanese adult cases

We assessed a large number of adults (368 from Australia and 494 from Japan) with de novo acute myeloid leukemia (AML) to define the biological differences between the two populations. In this study, AML was classified using the French–American–British (FAB) criteria into seven groups (M1–M7). M2 was more common in Japan than in Australia, whereas M4 occurred more frequently in Australia than in Japan. Other FAB subtypes were evenly distributed. Cytogenetically, Japanese M2 displayed a higher frequency of t(8;21) than Australian (33.1% vs 15.3%, P < 0.05). The t(15;17), inv/del(16), 11q23 aberrations and 5/7/8 abnormalities were seen at similar frequencies. immunophenotypically, japanese m4/m5 more frequently displayed cd13 and cd14 Than australian, whereas the stem cell markers, cd34 and hla-dr were observed at a relatively higher rate in australian m3 than in japanese m3. The b cell antigen, cd19 was more frequently seen in japanese m2 than in australian m2, but found more often in australian m5 than in japanese m5. In both populations, a close relationship was observed between the expression of cd19 and t(8;21). These findings suggest different biological characteristics of aml between the two populations, the main differences being generated by a higher frequency of t(8;21) chromosomal abnormality in japanese aml.

Characteristics of t(8;21) acute myeloid leukemia (AML) with additional chromosomal abnormality: concomitant trisomy 4 may constitute a distinctive subtype of t(8;21) AML.

t(8;21)(q22;q22) is the most frequently observed karyotypic abnormality associated with acute myeloid leukemia (AML), especially in FAB M2. Clinically, this type of AML often shows eosinophilia and has a high complete remission rate with conventional chemotherapy. t(8;21) AML is also frequently associated with additional karyotypic aberrations, such as a loss of the sex chromosome; however, it is unclear whether these aberrations change the biological and clinical characteristics of t(8;21) AML. To investigate this issue, 94 patients with t(8;21) AML were categorized according to their additional karyotypic aberrations, which were detected in more than three cases, and then morphologic features, phenotypes, expression of cytokine receptors, and clinical features were compared to t(8;21) AML without other additional aberrant karyotypes. t(8;21) AML with loss of the sex chromosome and abnormality of chromosome 9 were found in 27 cases (29.3%) and 10 cases (10.6%), respectively; however, no differences were observed from the t(8;21) AML without other additional karyotypes in terms of morphological and phenotypic features. There was also no significant difference in the clinical outcome among these three groups. On the other hand, trisomy 4 was found in three cases (3.2%) and these cells showed low expressions of CD19 (P=0.06) and IL-7 receptor (P=0.05), and high expressions of CD33 (P=0.13), CD18 (P=0.03), and CD56 (P=0.03) when compared to t(8;21) AML without additional karyotypes. Moreover, all three t(8;21) AML cases with trisomy 4 did not show eosinophilia in their bone marrow and died within 2.4 years. These observations suggest that additional karyotypic aberration, t(8;21) with trisomy 4 is rare, but it may constitute a distinctive subtype of t(8;21) AML.

Diagnostic and clinical importance of interleukin-2 receptor alpha chain expression on non-T-cell acute leukaemia cells

The expression of interleukin‐2 receptors (IL‐2R) was examined in 328 adult patients with non‐T‐cell (non‐T) acute leukaemia and blast crisis of chronic myelocytic leukaemia (CML.BC) using two monoclonal antibodies, anti‐Tac for IL‐2R α chain (IL‐2Rα) and Mikβ1 for IL‐2R β chain (IL‐2Rβ). Leukaemic cells in the following cases were positive for anti‐Tac; 28/192 of acute myelocytic leukaemia (AML), 24/44 CML‐BC, 4/28 CD19(+)CD10(‐) acute lympho‐blastic leukaemia (ALL), and 20/64 common ALL (c‐ALL). IL‐2Rβ was not detected on leukaemic cells of any case examined. Eleven of IL‐2Rα(+) AML were derived from myelodysplastic syndrome. None of the IL‐2Rα positive leukaemic cells responded to exogenous recombinant human IL‐2 (rhIL‐2) in culture. In addition, IL‐2Rα expression on non‐T leukaemic cells was closely correlated with coexpressing different lineage markers and the presence of the Philadelphia abnormality. Marked increase of serum soluble IL‐2Rα was demonstrated in the IL‐2Rα(+) patients examined. Clinically, the IL‐2Rα(+) patients showed significantly lower response to chemotherapy and poorer prognosis than IL‐2Rα(‐) patients. Our results clearly indicate the diagnostic importance of IL‐2Rα expression in non‐T acute leukaemia with a close relation to the particular cellular characteristics and the prognosis.

Clinical utility of a panfungal polymerase chain reaction assay for invasive fungal diseases in patients with haematologic disorders.

Invasive fungal diseases (IFDs) are life‐threatening events in patients with haematologic disorders, and the spectrum of the aetiological pathogens continues to expand. This study aimed to evaluate the clinical utility of a panfungal polymerase chain reaction (PCR) assay for the management of IFDs in such patients.

Establishment of an Undifferentiated Leukemia Cell Line (Kasumi-3) with t(3;7)(q27;q22) and Activation of the EVI1 Gene

A novel human leukemia cell line (Kasumi‐3) was established from the blast cells of a 57‐year‐old man suffering from myeloperoxidase‐negative acute leukemia. The cell line had five distinctive features, as follows. 1) Flow cytometric analyses showed cell surface expression of CD7, CD4, CD13, CD33, CD34, HLA‐DR and c‐Kit. This phenotype is compatible with that of acute myelocytic leukemia cells with the M0 subtype in the French‐American‐British classification. 2) Kasumi‐3 cells carried chromosomal abnormalities of t(3;7)(q27:q22), del(5)(q15), del(9)(q32), and add(12)(pll). The breakpoint of 3q27 was located near the EVI1 gene, and a high level of expression of the EVI1 gene was observed. 4) Kasumi‐3 cells treated with TPA showed maturation to monocytic lineage. 5) Treatment with either interleukin (IL)‐2, IL‐3, IL‐4, granulocyte‐macrophage colony‐stimulating or stem cell factor induced the proliferation of Kasnmi‐3 cells. Thus, the Kasumi‐3 cell line shows the characteristic features of undifferentiated leukemia. It should, therefore, be useful both for studying the biological characteristics of acute myelogenous leukemia M0 subtype and for investigating the role of the EVI1 gene in leukemogenesis.

Diagnostic Value of PCR Analysis of Bacteria and Fungi from Blood in Empiric-Therapy-Resistant Febrile Neutropenia

ABSTRACT This study aimed to assess the clinical utility of PCR for the analysis of bacteria and fungi from blood for the management of febrile neutropenic patients with hematologic malignancies. Using a PCR system able to detect a broad range of bacteria and fungi, we conducted a prospective pilot study of periodic analyses of blood from patients following intensive chemotherapy. When fever occurred, it was treated with empirical antibiotic therapy, basically without knowledge of the PCR results. In 23 febrile episodes during the neutropenic period, bacteria were detected by PCR in 11 cases, while the same species were identified by blood culture in 3 cases. In 10 out of 11 PCR-positive cases, fever could be managed by empirical therapy. In the empirical-therapy-resistant case, the identification of Stenotrophomonas maltophilia by PCR led to improvement of fever. No fungi were detected by PCR in febrile cases, while Aspergillus fumigatus was detected in one afebrile patient, several days before a clinical diagnosis was made. In subsequent sporadic PCR analyses in 15 cases of febrile neutropenia, bacteria were detected by both PCR and blood culture in 7 cases and by PCR alone in 6. Fungi were not detected. While fever was improved by empirical therapy in 12 out of the 13 PCR-positive cases, the identification of Pseudomonas aeruginosa by PCR in one therapy-resistant case contributed to the successful treatment of persistent fever. Our results indicate that PCR analysis of bacteria from blood provides essential information for managing empirical-therapy-resistant febrile neutropenia.

Clinical and prognostic significance of cytokine receptor expression in adult acute lymphoblastic leukemia : interleukin-2 receptor α-chain predicts a poor prognosis

We quantitatively assessed the expression of cytokine receptors (interleukin-2 receptor (IL-2R), IL-3R, IL-4R, IL-5R, IL-6R, IL-7R, granulocyte-macrophage colony-stimulating factor R (GM-CSFR), G-CSFR, c-fms, c-mpl, c-kit and FLT3) in cells from 211 adults with acute lymphoblastic leukemia (ALL) by flow cytometry and determined their prevalence and clinical significance. Although all cytokine receptors were expressed to various degrees, the levels of IL-3R α-chain (IL-3Rα), IL-2Rα, IL-2Rβ, IL-7Rα, common-Rγ(γc), c-mpl, c-kit and FLT3 exhibited a wide spectrum ⩾2000 sites/cell. Among them, IL-3Rα, IL-2Rα and FLT3 were highly expressed in B-lineage ALL, whereas IL-7Rα, γc and c-kit predominated in T-lineage ALL. Higher levels of IL-3Rα, IL-2Rα, c-kit and FLT3 correlated with the expression of CD13/33. Increased IL-2Rα levels related to the presence of Philadelphia chromosome (Ph), leukocytosis and shorter event-free survival (EFS). C-kit preferred in male. Elevated FLT3 levels correlated with age ⩾60 years. Multivariate analysis in B-lineage ALL revealed only IL-2Rα (P=0.028) and Ph (P=0.020) as independent factors for EFS. These findings suggest that several cytokine receptors associated with certain cellular and clinical features, but IL-2Rα solely had a prognostic value and should be considered as a major prognostic factor for adult ALL that is comparable with Ph.

Breakthrough disseminated zygomycosis induced massive gastrointestinal bleeding in a patient with acute myeloid leukemia receiving micafungin.

A 69-year-old man, who had been receiving prednisolone for 11 months for treatment of interstitial pneumonia, was diagnosed with acute myeloid leukemia. During induction therapy, he developed severe pneumonia. Although meropenem and micafungin were started, he died of circulatory failure owing to massive gastrointestinal bleeding. Autopsy specimens obtained from the stomach revealed fungal hyphae, which had invaded diffusely into submucosal vessels and caused the massive gastric bleeding. The same hyphae were also observed in both lungs. A diagnosis of disseminated zygomycosis was confirmed by its characteristic histopathological findings. Because zygomycetes are spontaneously resistant to the newer antifungal agents, such as voriconazole or micafungin, it seems likely that the prevalence of zygomycosis as a breakthrough infection may increase in the future. Zygomycosis is a rare, but life-threatening, deep fungal infection that appears in immunologically or metabolically compromised hosts. Its manifestations are clinically similar to those of invasive aspergillosis. In addition to the well-established epidemiology of zygomycosis, this case suggests the following new characteristics. (1) Although the gastrointestinal manifestation of zygomycosis is relatively rare, it is observed more frequently than invasive aspergillosis. (2) Gastrointestinal zygomycosis occasionally leads to the development of necrotic ulcers and may induce hemorrhagic shock.(3) We should be cautious of an occurrence of breakthrough zygomycosis when we use echinocandins for patients with known risk factors, especially steroid use and neutropenia. (4) For patients who are receiving broad-spectrum antibiotics and echinocandins, who are negative for culture studies and aspergillus antigen, and who present with unresolved fever, it is important to make a prompt clinical diagnosis of zygomycosis.

Biphasic expression of CD4 in acute myelocytic leukemia (AML) cells: AML of monocyte origin and hematopoietic precursor cell origin

In 227 of 495 (45.9%) Japanese adult patients with acute myelocytic leukemia (AML), leukemic cells expressed CD4. Incidence of CD4 expression in each FAB subtype was as follows: M1 37.4%, M2 33.7%, M3 35.4%, M4 65.0%, and M5 78.3%. The typical expression pattern of myelomonocytic differentiation antigens and cytokine receptors in CD4+ AML was CD34lowCD33high CD11bhighGM-CSFRhigh. AML cases with 11q23 abnormalities and with inv(16) were frequently CD4-positive. These data collectively indicate that CD4 expression in AML cells is associated with monocytic characteristics. However, CD4+CD34high AML cases appear to have unique immature characteristics including low expression of myelomonocytic differentiation antigens (ie CD33 and CD11b), and accumulation of chromosome abnormalities (ie t(8;21) in CD4lowCD34high AML and chromosome 7 abnormalities in CD4highCD34high AML). We speculate that these leukemia subsets originate from CD4+ hematopoietic precursor cells, therefore then should be considered separately from most of the CD4+ AML as represented by CD34lowCD33high CD11bhighGM-CSFRhigh. Overall survival of patients with CD4+ AML in our series was worse than that of those with CD4− AML (P = 0.0202).