Language：English   Publishing type：Research paper (scientific journal)  

Bacillus cereus is known to cause two types of food poisoning: emetic and diarrhoeal. Both diseases are usually self-limiting; however, severe cases have been reported, presenting with acute liver failure and encephalopathy, including rarely fatal cases of vomiting. Clinical laboratories do not routinely test for B. cereus in patients with gastrointestinal disease. Therefore, B. cereus causing food poisoning goes undetected. We report a successful isolation of emetic B. cereus from a patient with food poisoning who presented with severe vomiting, fulminant hepatic failure, and acute encephalopathy, by a non-conventional method. Initially, stool specimens from the patients were routinely cultured to identify the causative organisms of food poisoning. No foodborne pathogens were detected in this study. In contrast, additional clinical and epidemiological information strongly suggested food poisoning by emetic B. cereus. Consequently, we allowed Drigalski agar medium smeared with patient stool specimens to stand at room temperature (approximately 25 °C) for 9 days. After 9 days, mixed bacteria grown on the medium were inoculated onto mannitol egg yolk polymyxin (MYP) agar plates, a selective medium for B. cereus. Typical colonies of B. cereus developed on MYP agar plates. The isolated B. cereus had a cereulide-producing genetic locus (ces) gene encoding the emetic toxin cereulide. The method used in this case study was unique. This method is easy to apply after obtaining an additional clinical and epidemiological information, and this method will improve the diagnostic rate of severe B. cereus food poisoning. This will contribute to the advancement of therapeutics in the future.

DOI： 10.1016/j.jiac.2022.07.011

PubMed

Language：English  

RET gene variances confer susceptibility to Hirschsprung's disease (HSCR) with pathogenetic mutations being identified in half of familial cases. This investigation of familial HSCR was aimed to clarify the relationship between genetic mutations and clinical phenotype using next-generation sequencing. A novel c2313C > G(D771E) RET mutation was identified in all three affected family members. The mutation involved the kinase domain, which is believe to impair RET activity and intestinal function. A second RET mutation, c1465G > A(D489N), was found only in the extensive aganglionosis case. We conclude that the novel c2313C > A(D771E) mutation in RET may be pathogenic for HSCR, while the c1465C > G(D489N) mutation may be related to phenotype severity.

DOI： 10.1055/s-0040-1718385

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Acquired chronic pure red cell aplasia (PRCA) develops idiopathically or in association with other medical conditions, including T cell large granular lymphocytic leukemia (T-LGLL) and thymoma. T cell dysregulation is considered a cardinal pathogenesis of PRCA, but genetic-phenotypic associations in T cell abnormalities are largely unclear. We evaluated an extended cohort of 90 patients with acquired PRCA, including 26 with idiopathic, 36 with T-LGLL-associated and 15 with thymoma-associated PRCA, for their T cell immuno-phenotypes, clonalities and STAT3 mutations. TCR repertoire skewing of CD8+ T cells was detected in 37.5% of idiopathic, 66.7% of T-LGLL-associated and 25% of thymoma-associated PRCA patients, and restriction to Vβ1 was most prominent (41%). Clonalities of TCRβ or γ chain and STAT3 mutational status were statistically associated (P = 0.0398), and they were detected in all three subtypes. The overall response rate to cyclosporin A was 73.9%, without significant difference by subtypes nor STAT3 mutational status. The T cell dysregulations, such as TCR repertoire skewing with predominant Vβ1 usage, clonality and STAT3 mutations, were frequently found across the subtypes, and the close associations between them suggest that these T cell derangements reflect a common pathophysiological mechanism among these PRCA subtypes.

DOI： 10.1007/s12185-022-03310-2

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Allergic transfusion reactions (ATR) and febrile non-haemolytic transfusion reactions (FNHTR) are common transfusion-related adverse reactions; however, their pathogenesis remains unclear and it is difficult to predict their occurrence. Single-nucleotide polymorphisms (SNP) are related to the onset of various diseases and therapy-related adverse events; therefore, identification of SNP related to transfusion-related adverse reactions may help to elucidate the underlying mechanism and predict the onset of these reactions. MATERIALS AND METHODS: We retrospectively analysed the association between the onset of ATR or FNHTR and 22 allergic sensitisation-related SNP in 219 children (aged ≤20 years) who had haematological and oncological diseases and who had received transfusions of platelets and/or red blood cell concentrates. RESULTS: Among the 219 children, 105 had developed an ATR and/or FNHTR at least once. The patients who developed ATR frequently had a risk allele in rs6473223, while the patients who developed FNHTR frequently had a risk allele in rs10893845. Furthermore, patients who developed ATR accompanied by febrile symptoms also frequently had a risk allele in rs10893845, similar to patients who developed FNHTR. DISCUSSION: The results suggested that allergic sensitisation is associated with the onset of ATR and/or FNHTR in some patients. Although further prospective evaluation is necessary, analysis of these SNP might help to provide safer transfusion therapy by predicting patients at higher risk of transfusion-related adverse reactions and further clarifying the pathogenic mechanism underlying such reactions.

DOI： 10.2450/2021.0230-20

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

For relapsed/refractory (r/r) acute lymphocytic leukemia (ALL), there is a clinical question on how to combine blinatumomab and inotuzumab ozogamicin (InO), which are newly emerging immunotherapeutic agents, with conventional treatment. We report the case of an 11-year-old boy with B-cell ALL, who had a failed primary treatment and achieved molecular complete remission treated with a sequence therapy of InO and blinatumomab. Later, hematopoietic stem cell transplantation could be performed without major complications. Our case may suggest that the sequence therapy of InO and blinatumomab as a bridge-to hematopoietic stem cell transplantation could be effective in the treatment of pediatric r/r ALL.

DOI： 10.1097/MPH.0000000000002205

PubMed

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：(一社)日本検査血液学会  

MEF2D融合遺伝子は小児Bリンパ芽球性白血病(B-ALL)の1～4%程度に認められる予後不良因子であり、partner geneとしてBCL9など複数の遺伝子が知られている。MEF2D融合遺伝子を有するB-ALLの芽球は、細胞内に空胞を有することや約6割の症例でCD5を発現するなどの特徴的な形態および表面マーカー所見が報告されている。今回、細胞形態および表面マーカー所見を契機に診断に至ったMEF2D-BCL9を有する小児B-ALLの一例を経験した。症例は3歳女児、血液検査で芽球の出現を認め骨髄検査が施行された。骨髄中の芽球は84%を占め、一部の芽球に空胞を認め、表面マーカー解析ではB細胞系マーカーに加えCD5の発現を認めたことからMEF2D融合遺伝子の存在を推測した。追加で実施したMEF2D Break Apart Probeを用いたFISH解析にてMEF2D遺伝子のsplit signalを認め、その後全トランスクリプトーム解析にてMEF2D-BCL9を同定した。患児は治療中再発し、臍帯血移植が実施されたが2ヵ月後に再々発を来し原病死した。MEF2D融合遺伝子を有するB-ALLは難治性であり、予後予測や治療法選択の観点から本病型を診断することは意義があると考えられる。本病型の診断には特徴的な形態および表面マーカー所見を見逃さず、追加解析につなげることが重要であると考える。(著者抄録)

Language：English  

DOI： 10.1111/bjh.16820

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

We recently reported that methylation of PCDH17 gene is found in 30% of children with B-cell precursor acute lymphoblastic leukemia (ALL), and is significantly correlated to event-free or overall survival. We here evaluated PCDH17 mRNA expression in pediatric acute myeloid leukemia (AML) and ALL. PCDH17 mRNA expression levels in children with ALL/AML were lower than those in healthy counterparts. We next elucidated the mechanism underlying down-regulation of PCDH17 mRNA, using myeloid and lymphoid leukemic cell lines. Treatment with the histone deacetylase inhibitor trichostatin A (TSA) resulted in restoration of PCDH17 mRNA expression and growth inhibition in K562, HL60, REH, and RCH-ACV cell lines. Upregulation of PCDH17 mRNA expression resulted from histone H3 acetylation. Knockdown of the PCDH17 gene, caused by transduction of PCDH17-targeted shRNA, significantly enhanced the proliferation of KU812 cells. Meanwhile, overexpression of PCDH17 via retroviral-particle transfection substantially inhibited the growth of Kasumi1 cells. The fold-increase in PCDH17 mRNA expression mediated by 5-azacytidine, an inhibitor of DNA methyltransferase, was fundamentally lower than that produced by TSA. In conclusion, our results suggest that PCDH17 gene functions as a common tumor suppressor gene in leukemic cells, and that histone deacetylase inhibitors re-express PCDH17 mRNA to a greater extent than demethylation reagents.

DOI： 10.1007/s12185-019-02799-4

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND AND OBJECTIVES: Like adults, children can have allergic transfusion reactions (ATRs) and febrile non-haemolytic transfusion reactions (FNHTRs). But published information about the incidence of paediatric ATR and FNHTR is scarce. MATERIALS AND METHODS: This retrospective study was conducted from April 2002 to June 2018 on children who had ATRs and/or FNHTRs to platelet (PLT), red blood cell (RBC) or washed PLT/RBC concentrate transfusions. We analysed ATR/FNHTR clinical presentations, such as severity, time of occurrence and other features when they occurred. RESULTS: During the study, 2742 children received 23 444 bags of PLT and RBC concentrate (including washed products). ATRs occurred in 100 cases (3·6% of total patients), caused by 201 products (0·9% of total products). In contrast, 28 patients (1·0% of total patients) had 42 FNHTRs caused by 42 products (0·2% of total products). Upon analysis of cases with detailed clinical information, the median onset time for ATRs and FNHTRs was 2·0 h after the start of transfusion. Of the 40% of ATRs that necessitated the discontinuation of blood transfusions, 10% escalated to anaphylaxis. Compared with minor ATRs, anaphylaxis tended to develop quickly. Moreover, 96% of patients with FNHTRs had a fever less than 39°C. There were no associations between blood product types and numbers or occurrence patterns of these reactions. CONCLUSION: The occurrence of ATRs and FNHTRs in children was variable, although there are common features such as severity and time of occurrence.

DOI： 10.1111/vox.12833

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Chronic lymphoproliferative disorder of natural killer (NK) cells (CLPD-NK) is a rare disease with an indolent clinical course, which is characterized by persistent increase in large granular lymphocytes of NK-cell type. A somatic mutation in signal transducer and activator transcription 3 (STAT3) has been reported in patients with CLPD-NK; however, the details of the mutational profiles and their clinical significance remain unclear. We performed mutation analyses of the STAT3, STAT5B, and TNF-alpha-induced protein 3 (TNFAIP3) genes for mononuclear cell-derived DNA in 17 CLPD-NK patients using allele-specific polymerase chain reaction and amplicon sequencing. Mutations in STAT3 and TNFAIP3 were found in 29% (5/17) and 6% (1/17) of cases, respectively. All patients were negative for STAT5B mutations. In all three STAT3-mutation (+) patients studied, STAT3 mutations were restricted to sorted NK cells. STAT3 mutation (+) patients had a lower hemoglobin level (6.6 g/dL vs. 13.9 g/dL, P = 0.0044) and showed a trend toward reduced neutrophil counts (1.22 × 109/L vs. 3.10 × 109/L, P = 0.070) compared with the STAT3 mutation (-) patients. No mutations in these genes were found in patients with neuropathy. These results suggest that heterogeneity of CLPD-NK and STAT3-mutated NK cells may play a significant role in cytopenia in CLPD-NK patients.

DOI： 10.1007/s12185-019-02625-x

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

CD3+/CD57+ T-cell large granular lymphocyte leukemia (T-LGLL) is an indolent neoplasm, exhibiting mostly CD8+, less frequently CD4+ phenotypes, and T-LGLL consisting of 2 populations with CD8+ and CD4+ phenotypes is markedly rare. An 87-year-old female was admitted under a diagnosis of immune thrombocytopenia (ITP) with a platelet count of 5.0×109/L and increased number of LGL with unknown etiology. Her neutrophil count also decreased to 0.27×109/L and she was positive for antineutrophil antibody. The WBC count was 2.7×109/L with 34.7% LGL and flow cytometry (FCM) analysis revealed 16% CD3+/CD4+/CD8dim/CD57+ and 20.9% CD3+/CD8+/CD57+ populations. These populations also expressed granzyme B and perforin. Circulating mononuclear cells were found to be clonal by PCR analysis of T-cell receptor β-chain gene. Serum immunofixation and bone marrow FCM analyses demonstrated 2 clonal B-cells producing IgG-λ and IgA-λ. Deep amplicon sequencing of STAT3 and STAT5B genes revealed a STAT3 R302G mutation with an allele burden of 2.6%. The thrombocytopenia and neutropenia were successfully treated by prednisolone and romiplostim with negative conversion of antineutrophil antibody. This is the first reported case of T-LGLL with dual components of CD4+/CD8dim and CD4-/CD8+ populations in terms of multiple comorbidities related to the respective CD8+ and CD4+ T-LGLLs.

DOI： 10.3960/jslrt.19030

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Dysregulation of T-cell-mediated immunity is responsible for acquired pure red cell aplasia (PRCA). Although STAT3 mutations are frequently detected in patients with T-cell large granular lymphocytic leukemia (T-LGLL), which is often complicated by PRCA and which is also reported to be associated with acquired aplastic anemia (AA) and myelodysplastic syndrome (MDS), whether STAT3-mutated T cells are involved in the pathophysiology of PRCA and other types of bone marrow failure remains unknown. We performed STAT3 mutation analyses of the peripheral blood mononuclear cells from PRCA patients (n = 42), AA (n = 54), AA-paroxysmal nocturnal hemoglobinuria (AA-PNH; n = 7), and MDS (n = 21) using an allele-specific polymerase chain reaction and amplicon sequencing. STAT3 mutations were not detected in any of the 82 patients with AA/PNH/MDS but were detected in 43% of the 42 PRCA patients. In all 7 STAT3-mutation-positive patients who were studied, the STAT3 mutations were restricted to sorted CD8+ T cells. The prevalence of STAT3 mutation in idiopathic, thymoma-associated, autoimmune disorder-associated, and T-LGLL-associated PRCA was 33% (5 of 15), 29% (2 of 7), 20% (1 of 5), and 77% (10 of 13), respectively. The STAT3-mutation-positive patients were younger (median age, 63 vs 73 years; P= .026) and less responsive to cyclosporine (46% [6 of 13] vs 100% [8 of 8]; P= .0092) in comparison with STAT3-mutation-negative patients. The data suggest that STAT3-mutated CD8+ T cells may be closely involved in the selective inhibition of erythroid progenitors in PRCA patients.

DOI： 10.1182/bloodadvances.2018022723

PubMed

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND AND OBJECTIVES: Adverse reactions to platelet transfusions are a problem. Children with primary haematological and malignant diseases may experience allergic transfusion reactions (ATRs) to platelet concentrates (PCs), which can be prevented by giving washed PCs. A new platelet additive solution, using bicarbonated Ringer's solution and acid-citrate-dextrose formula A (BRS-A), may be better for platelet washing and storage, but clinical data are scarce. MATERIALS AND METHODS: A retrospective cohort study for consecutive cases was performed between 2013 and 2017. For 24 months, we transfused washed PCs containing BRS-A to children with primary haematological and malignant diseases and previous adverse reactions. Patients transfused with conventional PCs (containing residual plasma) were assigned as controls, and results were compared in terms of frequency of ATRs, corrected count increment (CCI) and occurrence of bleeding. We also studied children transfused with PCs washed by a different system as historical controls. RESULTS: Thirty-two patients received 377 conventional PC transfusions. ATRs occurred in 12 (37·5%) patients from transfused with 18 (4·8%) bags. Thirteen patients, who experienced reactions to regular PCs in plasma, then received 119 transfusion bags of washed PCs containing BRS-A, and none had ATRs to washed PCs containing BRS-A. Before study period, six patients transfused 137 classical washed PCs with different platelet additive solution, under same indication, ATRs occurred in one (16·7%) patient from transfused with one (0·7%) bags. CCIs (24 h) in were lower with classical washed PCs (1·26 ± 0·54) compared to regular PCs in plasma (2·07 ± 0·76) (P < 0·001), but there was no difference between washed PCs containing BRS-A (2·14 ± 0·77) and regular PCs (2·21 ± 0·79) (P = 0·769), and we saw no post-transfusion bleeding. CONCLUSION: Washed PCs containing BRS-A appear to prevent ATRs without loss of transfusion efficacy in children with primary haematological and malignant diseases. Their efficacy should be further evaluated through larger prospective clinical trials.

DOI： 10.1111/vox.12608

PubMed