Chromosomal aberrations in congenital bone marrow failure disorders—an early indicator for leukemogenesis?

As chromosomal instability may contribute to leukemogenesis in patients with congenital bone marrow failure (CBMF) disorders, it was the aim of this study to characterize chromosomally aberrant clones that arise during the clinical course of disease by means of R-banding and fluorescence in situ hybridization (FISH) analyses. In addition, multicolor-FISH and array-comparative genomic hybridization (CGH) were applied to characterize clonal chromosome aberrations in more detail. Between January 2004 and December 2005, we prospectively analyzed 90 samples of 73 patients with proven or suspected CBMF disorders enrolled in a German Study Network of CBMF diseases. Clonal aberrations could be identified in four of 73 patients examined. In one child with congenital thrombocytopenia, Jacobsen syndrome [del(11)(q24)c] was diagnosed, and thus a CBMF could be excluded. In a girl with Shwachman–Diamond syndrome, two independent clones, one with an isochromosome i(7)(q10), another with a complex aberrant karyotype, were identified. Simultaneously, transition into a myelodysplastic syndrome (MDS) occurred. The brother, who was also afflicted with Shwachman-Diamond syndrome, showed an isochromosome i(7q) as a single aberration. In the fourth patient with severe congenital neutropenia, an add(21)(q22) marker containing a low-level amplification of the AML1 gene was identified at the time point of transition into acute myelogenous leukemia (AML). In summary, we suggest that follow-up of patients with CBMF using chromosome and FISH analyses will be helpful for the early detection of transition into MDS or AML and thus should be an integral part of the clinical management of these patients.     

Impaired megakaryopoiesis in patients with chronic idiopathic neutropenia is associated with increased transforming growth factor beta1 production in the bone marrow

Patients with chronic idiopathic neutropenia (CIN) display relatively low peripheral blood platelet counts and hypo-lobulated megakaryocytes in the bone marrow (BM). The underlying pathogenetic mechanismswere probed by studying the reserves and clonogenic potential of BM megakaryocytic progenitor cells using flow-cytometry and a collagen-based clonogenic assay for the identification of megakaryocyte colony-forming units (CFU-Meg). Thrombopoietin (TPO) and transforming growth factor-beta1 (TGFbeta1) levels were also evaluated in long-term BM culture supernatants using an enzyme-linked immunosorbent assay. CIN patients (n = 39) showed a low proportion of BM CD34(+)/CD61(+) megakaryocytic progenitor cells and low frequency of early and mixed CFU-Meg in the BM mononuclear, but not CD34(+), cell fraction, compared with healthy controls (n = 20). TPO and TGFbeta1 levels were significantly higher in patients compared with controls. TPO levels inversely correlated with platelet counts whereas TGFbeta1 values correlated inversely with CD34(+)/CD61(+) and CFU-Meg megakaryocytic progenitor cell numbers and positively with TPO levels. The addition of an anti-TGFbeta1 neutralising antibody significantly increased the numbers of CFU-Meg in CIN patients but not in controls, compared with baseline. These data suggest that increased local production of TGFbeta1 probably affects the BM megakaryocytic progenitor cell growth in CIN whereas the compensatory production of TPO finally balances the TGFbeta1-induced inhibitory effect.     

Transfusion-related acute lung injury in a neutropenic patient

Transfusion-related acute lung injury (TRALI) is a leading cause of transfusion related morbidity and mortality. Current concepts regarding the pathogenesis of this disorder imply a "two-hit" model in which neutrophils are sequestered in the pulmonary capillary bed, and subsequently activated by substances in the transfused blood product. We report a case of TRALI in a patient with neutropenia and discuss the possible factors contributing to the respiratory symptoms in this patient. We also emphasise the importance of recognising mild cases of TRALI in order to investigate the implicated donor/s appropriately, and to minimise the risk for more severe episodes in other patients.     

慢性乙型肝炎患者加用益血生胶囊预防α干扰素所致的骨髓抑制

目的：观察α干扰素（IFN-α）治疗慢性乙型肝炎（CHB）时，加用益血生胶囊对防治IFN-α相关性骨髓抑制的作用。方法：105例经肝穿刺活检证实的HBeAg阳性CHB患者，给予IFN-α2b，5MU／次，每周3次，依患者意愿，其中62例加用益血生胶囊口服（试验组），43例未加用（对照组）。以Abbott EIA试剂检测HBeAg，以荧光定量PCR法测定HBV DNA。所有统计学分析均采用意向治疗分析。结果：两组患者性别、年龄、肝组织炎症活动度、肝组织纤维化分期、血清丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、HBV DNA水平以及治疗前外周血白细胞计数、中性粒细胞计数和血小板计数、IFN-α疗程之间差异均无显著性意义。试验组加用益血生胶囊2．0（1．0～3．2）个月。治疗结束时，试验组、对照组联合应答率分别为42．9％（27／62）和33．3％（14／42）（Х^2=0．960，P=0．327），随访6个月时分别为44．40％（28／62）和33．3％（14／43）（Х^2=1．296，P=0．255）；试验组疗程中白细胞减少（〈4．0×10^9／L）发生率14．5％（9／62）、中性粒细胞减少（〈2．0×10^9／L）发生率19．4％（12／62）、血小板减少（〈100×10^9／L）发生率17．7％（11／62），对照组分别为34．9％（15／43）（Х^2=5．974，P=0．015）、37．2％（16／43）（Х^2=4．139，P=0．042）和41．9％（18／43）（Х^2=7．388，P=0．007）。结论：以IFN-α治疗慢性乙型肝炎时，加用益血生胶囊可减少和减轻IFN-α相关性骨髓抑制。     

Neutrophil elastase mutations and risk of leukaemia in severe congenital neutropenia

Severe congenital neutropenia (SCN) is a heterogeneous bone marrow failure syndrome predisposing to myelodysplastic syndrome and acute myeloid leukaemia (MDS/AML). We studied 82 North American and Australian SCN patients enrolled in the Severe Chronic Neutropenia International Registry who were on long-term treatment with granulocyte colony-stimulating factor and for whom the neutrophil elastase ( ELA2 ) gene was sequenced. There was no significant difference in the risk of MDS/AML in patients with mutant versus wild-type ELA2 : the respective cumulative incidences at 15 years were 36% and 25% ( P  =   0·96). Patients with either mutant or wild-type ELA2 should be followed closely for leukaemic transformation.     

Serum granulocyte colony-stimulating factor levels in patients with chronic neutropenia of childhood: modulation of G-CSF levels by myeloid precursor cell mass

The serum G-CSF levels of eight patients with severe congenital neutropenia (SCN) were found to be significantly higher than those of 22 patients with chronic benign neutropenia (CBN). The relative number of cells expressing the G-CSF receptor in light density bone marrow cells (LDBMC) was lower in patients with SCN than in patients with CBN or in normal subjects. When recombinant human G-CSF was incubated with LDBMC, G-CSF levels were decreased by LDBMC from normal subjects and CBN patients, but not by those from SCN patients. Serum G-CSF concentrations, which are affected by mature neutrophils, may also be modulated by myeloid precursor cells in the bone marrow.     

Diagnostic yield of bronchoscopic sampling in febrile neutropenic patients with pulmonary infiltrate and haematological disorders

Background: The development of pulmonary infiltrate in neutropenic patients is potentially life‐threatening, and requires early diagnosis and treatment. Bronchoscopic sampling is an established form of investigation in such patients. Aim: The aim of the study is to determine the diagnostic yield and complication rate of bronchoscopic sampling in patients with a haematological disorder presenting with febrile neutropenia and pulmonary infiltrate. Methods: Medical records and laboratory investigations were retrospectively reviewed for all patients with a haematological disorder who underwent flexible bronchoscopy and bronchoalveolar lavage (BAL) or bronchial washing (BW) at Auckland City Hospital, New Zealand, after presenting with febrile neutropenia and pulmonary infiltrate between January 2008 and December 2009. Demographic, clinical, radiological and microbiological data, procedure‐related complications and treatment were recorded. Modifications to treatment regimens as a result of bronchoscopy and 30‐day mortality were recorded. Results: Out of 678 bronchoscopies performed during this period, 26 were in patients with a haematological disorder presenting with febrile neutropenia and pulmonary infiltrate. Most patients had a haematological malignancy (19/26). Two (7.7%) patients reported minor haemoptysis. No biopsies were performed. Positive microbiological samples were obtained with BAL/BW in 23% of patients. The most common organisms identified were Aspergillus species (15.4%); other organisms were Candida (11.6%) and Streptococcus pneumoniae (3.9%). The bronchoscopic results altered the clinical management of 10 (38.4%) patients. The 30‐day mortality rate was 19.2%, but no deaths were related to the procedure. Conclusions: In haematology patients presenting with febrile neutropenia and pulmonary infiltrate, bronchoscopy is a safe procedure that plays a significant role in management.     

Liposomal amphotericin B compared with amphotericin B deoxycholate in the treatment of documented and suspected neutropenia-associated invasive fungal infections

It has been suggested that a better outcome of neutropenia-associated invasive fungal infections can be achieved when high doses of lipid formulations of amphotericin B are used. We now report a randomized multicentre study comparing liposomal amphotericin B (AmBisome, 5 mg/kg/d) to amphotericin B deoxycholate (AmB, 1 mg/kg/d) in the treatment of these infections. Of 106 possible patients, 66 were enrolled and analysed for efficacy: nine had documented fungaemia, 17 had other invasive mould infections and 40 had suspected pulmonary aspergillosis. After completion of the course medication, in the AmBisome group ( n  = 32) 14 patients had achieved complete response, seven a partial response and 11 were failures as compared to 6, 13 and 15 patients ( n  = 34) treated with AmB ( P  = 0.09); P  = 0.03 for complete responders. A favourable trend for AmBisome was found at day 14, in patients with documented infections and in patients with pulmonary aspergillosis ( P  = 0.05 and P  = 0.096 respectively). Mortality rates were lower in patients treated with AmBisome (adjusted for malignancy status, P  = 0.03). More patients on AmB had a >100% increase of their baseline serum creatinine ( P  < 0.001).
The results indicate that, in neutropenic patients with documented or suspected invasive fungal infections AmBisome 5 mg/kg/d was superior to AmB 1 mg/kg/d with respect to efficacy and safety.