L-asparaginase as an efficient salvage therapy for refractory acute myeloid leukemia with chromosome 7 abnormalities: a case series.

Acute myeloid leukemia (AML) with chromosome 7 abnormalities has a dismal prognosis due to a poor complete remission (CR) rate after induction chemotherapy. Although various salvage therapies for refractory AML have been developed for adults, few salvage therapies are available for children. Here, we report the cases of three patients with refractory AML with chromosome 7 abnormalities (Patient 1, with inv(3)(q21;3q26.2) and monosomy 7; Patient 2, with der(7)t(1;7)(?;q22); patient 3, with monosomy 7) who were successfully treated with L-asparaginase (L-ASP) as salvage therapy. All three patients achieved CR several weeks after L-ASP treatment, and two patients successfully underwent hematopoietic stem cell transplantation (HSCT). Patient 2 relapsed after the second HSCT in the form of an intracranial lesion, but achieved and sustained CR for 3 years with weekly L-ASP maintenance therapy. Immunohistochemical staining for asparagine synthetase (ASNS), whose gene is located at 7q21.3, was performed for each patient. The result was negative in all patients, which suggests that haploid 7q21.3 and other chromosome 7 abnormalities leading to haploinsufficiency of ASNS contribute to a high susceptibility to L-ASP. In conclusion, L-ASP is a promising salvage therapy for refractory AML with chromosome 7 abnormalities, which are associated with ASNS haploinsufficiency.

Epidemiology conduction of paediatric rheumatic diseases based on the registry database of the Pediatric Rheumatology Association of Japan.

OBJECTIVES: Although epidemiological surveys of paediatric rheumatic diseases in Japan have been conducted, they were single surveys with no continuity. This is the first report of the Pediatric Rheumatology Association of Japan registry database, which was established to continuously collect data for paediatric rheumatic diseases. METHODS: Pediatric Rheumatology International Collaborate Unit Registry version 2 (PRICUREv2) is a registry database established by the Pediatric Rheumatology Association of Japan. The registry data were analysed for the age of onset, time to diagnosis, sex differences, seasonality, and other factors. RESULTS: Our data showed the same trend regarding rates of paediatric rheumatic diseases reported in Japan and other countries. The age of onset was lower in juvenile idiopathic arthritis (JIA) and juvenile dermatomyositis and higher in systemic lupus erythematosus and Sjögren's syndrome. The time to diagnosis was relatively short in JIA and systemic lupus erythematosus but longer in juvenile dermatomyositis and Sjögren's syndrome. Rheumatoid factor-positive polyarticular JIA showed a seasonality cluster with regard to onset. CONCLUSION: PRICUREv2 aided the retrieval and evaluation of current epidemiological information on patients with paediatric rheumatic diseases. It is expected that the data collection will be continued and will be useful for expanding research in Japan.

Comparison of Emergence Agitation Scale Scores and Creatine Kinase Levels After General Anesthesia in Children: A Prospective Cohort Study.

Introduction A simple indicator of muscle damage is creatine kinase (CK). Although CK elevation is informative for malignant hyperthermia, no study has examined the relationship between the anesthetically awake state and CK in children. We aimed to prospectively examine the relationship between the awakening state and CK on the day after surgery in children who have undergone anesthesia with volatile inhalation anesthetics. Methods The study included 119 patients aged 0-15 years and scheduled to undergo general anesthesia for cleft lip and palate-related surgery. Emergence agitation (EA) was assessed after completion of general anesthesia using the five-point EA scale, and patients were divided into the following five groups according to the EA score: EA1, EA2, EA3, EA4, and EA5. The primary outcome was ΔCK (comparison of CK values one week prior to surgery to CK values on the day after surgery) in each EA group. The secondary outcome was ΔCK when the EA score was divided into the following two groups: EA ≤2 (EA score of 1 or 2) and EA ≥3 (EA score of 3, 4, or 5). Results The median ΔCK values in the EA1 to EA5 groups were 3 (quartile -19~9), 5 (-32~88), 99.5 (-18~190.5), 121 (29~219.5), and 144 (41~340.5), respectively, indicating a statistically significant difference overall. Statistically significant differences were also observed between the EA1 and EA4 groups and between the EA2 and EA4 groups. The median ΔCK values in the EA ≤2 and EA ≥3 groups were 3 (quartile -27~85) and 108 (23.5~206.7), respectively, indicating a statistically significant difference. Conclusion The results of this study revealed that a higher EA score at the time of anesthesia awakening is associated with a larger ΔCK, indicating that a high CK level on the day after surgery is highly related to the state of the patient upon awakening.

Increased Pentraxin 3 Levels Correlate With IVIG Responsiveness and Coronary Artery Aneurysm Formation in Kawasaki Disease.

Kawasaki disease (KD) is a febrile disease of childhood characterized by systemic vasculitis that can lead to coronary artery lesions (CAL). This was a prospective cohort study to determine the levels of the pentraxin 3 (PTX3), soluble CD24-Subtype (Presepsin) and N-terminal pro-brain natriuretic peptide (NT-pro BNP) in consecutive KD patients. From January 2013 to March 2015, all patients with KD admitted to Aichi Medical University Hospital who provided consent had their plasma saved before IVIG administration. In total, 97 cases were registered. 22 cases of incomplete KD were excluded from the outcome analysis. The total 75 cases were used for statistical analyses. A PTX3 threshold of >7.92 ng/ml provided a specificity of 88.5 %, a sensitivity of 94.4 %, and a likelihood ratio as high as 15.92 for the diagnosis of KD compared with febrile non-KD controls. Although an echocardiographic diagnosis of CAL in the early course of the disease was confirmed in 24 cases, it was not in the remaining 51 cases. Neither NT-proBNP nor Presepsin had statistical significance for the prediction of the echocardiographic CAL diagnosis. Only PTX3 was significantly predictive of the echocardiographic CAL diagnosis (p=0.01). The PTX3 level was significantly higher in the intravenous immunoglobulin (IVIG) non-responders (45.9±7.45) than in the IVIG responders (17.0 ± 1.46 ng/ml) (p< 0.001). The PTX3 level also correlated with the number of IVIG treatment courses needed to resolve fever (R² =0.64). Persistent CAL (pCAL) formation was observed in three cases; one of aneurysm only and two aneurysms with dilatations. The patients with pCAL had significantly higher PTX3 levels (85 ± 8.4 ng/ml) than patients without pCAL (22 ± 2.2 ng/ml) (p< 0.0001). In terms of pCAL prediction, the area under the curve (AUC) of receiver operating characteristic ROC curve of PTX3 was 0.99, and it was significantly greater than that of Presepsin (0.67) or NT-proBNP (0.75). PTX3 is a soluble pattern recognition molecule that acts as a main component of the innate immune system. These data suggest that PTX3 can be utilized as a definitive biomarker for the prediction of IVIG resistance and subsequent CAL formation in patients with KD.

Thrombotic Microangiopathy Associated with Macrophage Activation Syndrome: A Multinational Study of 23 Patients.

OBJECTIVE: To describe the clinical characteristics, treatment, and outcomes of a multinational cohort of patients with macrophage activation syndrome (MAS) and thrombotic microangiopathy (TMA). STUDY DESIGN: International pediatric rheumatologists were asked to collect retrospectively the data of patients with the co-occurrence of MAS and TMA. Clinical and laboratory features of patients with systemic juvenile idiopathic arthritis (sJIA)-associated MAS and TMA were compared with those of an historical cohort of patients with sJIA and MAS. RESULTS: Twenty-three patients with MAS and TMA were enrolled: 17 had sJIA, 2 systemic lupus erythematosus, 1 juvenile dermatomyositis, 1 mixed connective tissue disease, and 2 undifferentiated connective tissue disease. Compared with the historical cohort of MAS, patients with sJIA with coexistent MAS and TMA had higher frequencies of renal failure and neurologic involvement, hemorrhage, jaundice, and respiratory symptoms, as well as more severe anemia and thrombocytopenia, higher levels of alanine aminotransferase, lactate dehydrogenase, bilirubin and D-dimer, and lower levels of albumin and fibrinogen. They also required admission to the intensive care unit more frequently. Among patients tested, complement abnormalities and reduced ADAMTS13 activity were observed in 64.3% and 44.4% of cases, respectively. All patients received glucocorticoids. Treatment for TMA included plasma-exchange, eculizumab, and rituximab. CONCLUSIONS: The possible coexistence of MAS and TMA in rheumatic diseases may be underrecognized. This association should be considered in patients with MAS who develop disproportionate anemia, thrombocytopenia, and lactate dehydrogenase increase, or have multiorgan failure.

Intensification of induction therapy and prolongation of maintenance therapy did not improve the outcome of pediatric Langerhans cell histiocytosis with single-system multifocal bone lesions: results of the Japan Langerhans Cell Histiocytosis Study Group-02 Protocol Study.

Langerhans cell histiocytosis (LCH) with single-system (SS) multifocal bone (MFB) lesions is rarely fatal, but patients may experience relapses and develop LCH-associated sequelae. To evaluate effect on outcomes of pediatric multifocal LCH, we tested a treatment protocol modified from the Japan Langerhans Cell Histiocytosis Study Group (JLSG)-96 study. We assessed the outcomes of all consecutive newly diagnosed pediatric patients with LCH with SS-MFB lesions who were treated with JLSG-02 protocol in 2002-2009. JLSG-02 was modified from JLSG-96 as follows: increased prednisolone dosage at the induction phase and extension of maintenance therapy duration from 24 to 48 weeks. In total, 82 patients with a median follow-up duration of 8.0 years were eligible for analysis. At 6 weeks, 92.7% responded to induction; however, 27.6% of responders experienced relapses. In total, 4.8% developed central nervous system-related sequelae, including central diabetes insipidus and neurodegeneration, which were associated with relapse. None of the patients died. The 5-year event-free survival rates were not different between JLSG-02 and -96 cohort (66.7 vs. 65.1%; p = 0.697). Modification of previous treatment protocol did not contribute to improvement of outcomes in LCH with SS-MFB lesions.

Development and Initial Validation of the Macrophage Activation Syndrome/Primary Hemophagocytic Lymphohistiocytosis Score, a Diagnostic Tool that Differentiates Primary Hemophagocytic Lymphohistiocytosis from Macrophage Activation Syndrome.

OBJECTIVE: To develop and validate a diagnostic score that assists in discriminating primary hemophagocytic lymphohistiocytosis (pHLH) from macrophage activation syndrome (MAS) related to systemic juvenile idiopathic arthritis. STUDY DESIGN: The clinical, laboratory, and histopathologic features of 362 patients with MAS and 258 patients with pHLH were collected in a multinational collaborative study. Eighty percent of the population was assessed to develop the score and the remaining 20% constituted the validation sample. Variables that entered the best fitted model of logistic regression were assigned a score, based on their statistical weight. The MAS/HLH (MH) score was made up with the individual scores of selected variables. The cutoff in the MH score that discriminated pHLH from MAS best was calculated by means of receiver operating characteristic curve analysis. Score performance was examined in both developmental and validation samples. RESULTS: Six variables composed the MH score: age at onset, neutrophil count, fibrinogen, splenomegaly, platelet count, and hemoglobin. The MH score ranged from 0 to 123, and its median value was 97 (1st-3rd quartile 75-123) and 12 (1st-3rd quartile 11-34) in pHLH and MAS, respectively. The probability of a diagnosis of pHLH ranged from <1% for a score of <11 to >99% for a score of ≥123. A cutoff value of ≥60 revealed the best performance in discriminating pHLH from MAS. CONCLUSION: The MH score is a powerful tool that may aid practitioners to identify patients who are more likely to have pHLH and, thus, could be prioritized for functional and genetic testing.

2016 Classification Criteria for Macrophage Activation Syndrome Complicating Systemic Juvenile Idiopathic Arthritis: A European League Against Rheumatism/American College of Rheumatology/Paediatric Rheumatology International Trials Organisation Collaborative Initiative.

To develop criteria for the classification of macrophage activation syndrome (MAS) in patients with systemic juvenile idiopathic arthritis (JIA). A multistep process, based on a combination of expert consensus and analysis of real patient data, was conducted. A panel of 28 experts was first asked to classify 428 patient profiles as having or not having MAS, based on clinical and laboratory features at the time of disease onset. The 428 profiles comprised 161 patients with systemic JIA-associated MAS and 267 patients with a condition that could potentially be confused with MAS (active systemic JIA without evidence of MAS, or systemic infection). Next, the ability of candidate criteria to classify individual patients as having MAS or not having MAS was assessed by evaluating the agreement between the classification yielded using the criteria and the consensus classification of the experts. The final criteria were selected in a consensus conference. Experts achieved consensus on the classification of 391 of the 428 patient profiles (91.4%). A total of 982 candidate criteria were tested statistically. The 37 best-performing criteria and 8 criteria obtained from the literature were evaluated at the consensus conference. During the conference, 82% consensus among experts was reached on the final MAS classification criteria. In validation analyses, these criteria had a sensitivity of 0.73 and a specificity of 0.99. Agreement between the classification (MAS or not MAS) obtained using the criteria and the original diagnosis made by the treating physician was high (κ=0.76). We have developed a set of classification criteria for MAS complicating systemic JIA and provided preliminary evidence of its validity. Use of these criteria will potentially improve understanding of MAS in systemic JIA and enhance efforts to discover effective therapies, by ensuring appropriate patient enrollment in studies.

Expert consensus on dynamics of laboratory tests for diagnosis of macrophage activation syndrome complicating systemic juvenile idiopathic arthritis.

OBJECTIVE: To identify which laboratory tests that change over time are most valuable for the timely diagnosis of macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (sJIA). METHODS: A multistep process, based on a combination of expert consensus and analysis of real patient data, was conducted. A panel of experts was first asked to evaluate 115 profiles of patients with MAS, which included the values of laboratory tests at the pre-MAS visit and at MAS onset, and the change in values between the two time points. The experts were asked to choose the 5 laboratory tests in which change was most important for the diagnosis of MAS and to rank the 5 selected tests in order of importance. The relevance of change in laboratory parameters was further discussed and ranked by the same experts at a consensus conference. RESULTS: Platelet count was the most frequently selected test, followed by ferritin level, aspartate aminotransferase (AST), white cell count, neutrophil count, and fibrinogen and erythrocyte sedimentation rate. Ferritin was most frequently assigned the highest score. At the end of the process, platelet count, ferritin level and AST were the laboratory tests in which the experts found change over time to be most important. CONCLUSIONS: We identified the laboratory tests in which change over time is most valuable for the early diagnosis of MAS in sJIA. The dynamics of laboratory values during the course of MAS should be further scrutinised in a prospective study in order to establish the optimal cut-off values for their variation.

2016 Classification Criteria for Macrophage Activation Syndrome Complicating Systemic Juvenile Idiopathic Arthritis: A European League Against Rheumatism/American College of Rheumatology/Paediatric Rheumatology International Trials Organisation Collaborative Initiative.

OBJECTIVE: To develop criteria for the classification of macrophage activation syndrome (MAS) in patients with systemic juvenile idiopathic arthritis (JIA). METHODS: A multistep process, based on a combination of expert consensus and analysis of real patient data, was conducted. A panel of 28 experts was first asked to classify 428 patient profiles as having or not having MAS, based on clinical and laboratory features at the time of disease onset. The 428 profiles comprised 161 patients with systemic JIA-associated MAS and 267 patients with a condition that could potentially be confused with MAS (active systemic JIA without evidence of MAS, or systemic infection). Next, the ability of candidate criteria to classify individual patients as having MAS or not having MAS was assessed by evaluating the agreement between the classification yielded using the criteria and the consensus classification of the experts. The final criteria were selected in a consensus conference. RESULTS: Experts achieved consensus on the classification of 391 of the 428 patient profiles (91.4%). A total of 982 candidate criteria were tested statistically. The 37 best-performing criteria and 8 criteria obtained from the literature were evaluated at the consensus conference. During the conference, 82% consensus among experts was reached on the final MAS classification criteria. In validation analyses, these criteria had a sensitivity of 0.73 and a specificity of 0.99. Agreement between the classification (MAS or not MAS) obtained using the criteria and the original diagnosis made by the treating physician was high (κ = 0.76). CONCLUSION: We have developed a set of classification criteria for MAS complicating systemic JIA and provided preliminary evidence of its validity. Use of these criteria will potentially improve understanding of MAS in systemic JIA and enhance efforts to discover effective therapies, by ensuring appropriate patient enrollment in studies.

Late-Onset Combined Immunodeficiency with a Novel IL2RG Mutation and Probable Revertant Somatic Mosaicism.

Primary immunodeficiency disease (PID) is caused by mutations of more than two hundred immunity-related genes. In addition to the heterogeneity of the diseases, the atypical presentation of each disease caused by hypomorphic mutations or somatic mosaicism makes genetic diagnosis challenging. Next-generation sequencing tests all genes simultaneously and has proven its innovative efficacy in genomics. We describe a male PID patient without any family history of immunodeficiency. This patient suffered from recurrent infections from 1 year of age. Laboratory analysis showed hypogammaglobulinemia. T, B, and NK cells were present, but the T cell proliferative response decreased. Whole-exome sequencing analysis identified an IL2RG p.P58T missense mutation. CD8(+) and CD56(+) cells showed revertant somatic mosaicism to the wild-type allele. A late-onset and atypical presentation of the X-linked severe combined immunodeficiency (X-SCID) phenotype might be associated with revertant somatic mosaicism in T and NK cells. This patient is the seventh reported case of X-SCID with revertant somatic mosaicism. His classical clinical management did not result in a molecular diagnosis because of the atypical presentation. The coverage that is provided by whole-exome sequencing of most PID genes effectively excluded differential diagnoses other than X-SCID. As next-generation sequencing becomes available in clinical practice, it will enhance our knowledge of PID and rescue currently undiagnosed patients.

Hematopoietic stem cell transplantation for patients with acute lymphoblastic leukemia and Down syndrome.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is one curable option for high-risk acute lymphoblastic leukemia (ALL); however, transplant-related toxicities might be severe in patients with Down syndrome and ALL (DS-ALL). PROCEDURE: HSCTs performed in patients with DS-ALL were identified in the Japan Society for Hematopoietic Cell Transplantation registry. RESULTS: In the registry data, 11 patients with DS-ALL were identified. The median age at HSCT was 9 years (range: 6-22 years). Six patients underwent HSCT at non-remission status. Allogeneic grafts were utilized in all patients, including eight patients who received HSCT from unrelated donors. Reduced intensity conditioning regimens were used in three patients. All patients achieved neutrophil engraftment by a median of day 18 (range: day 11-61). Ten patients experienced grade 3 or more infectious episodes. Six patients experienced complications of the respiratory system. The incidences of II-IV or III-IV acute GVHD were nine (81.8%) or seven patients (63.6%), respectively. Chronic GVHD was observed in five (55.6%) out of nine evaluable patients. Seven patients died at a median of 6 months (range: 0-24 months) after HSCT. Two-year relapse-free and overall survival were 33.3% (95% CI: 2.5-64.1%) or 37.5% (95% CI: 5.9-69.1%), respectively. The causes of death were relapse (n = 2), infection (n = 2), bleeding (n = 1), thrombotic microangiopathy (n = 1), and chronic GVHD (n = 1). CONCLUSIONS: Therapy-related mortality accounted for five out of seven deceased patients in this case series. Attempts to reduce toxicities should be considered in HSCT for patients with DS-ALL.

Clinical features, treatment, and outcome of macrophage activation syndrome complicating systemic juvenile idiopathic arthritis: a multinational, multicenter study of 362 patients.

OBJECTIVE: To describe the clinical, laboratory, and histopathologic features, current treatment, and outcome of patients with macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (JIA). METHODS: In this multinational, multicenter study, pediatric rheumatologists and hemato-oncologists entered patient data collected retrospectively into a web-based database. RESULTS: A total of 362 patients, 22% of whom had MAS at the onset of systemic JIA, were included in the study by 95 investigators from 33 countries. The most frequent clinical manifestations were fever (96%), hepatomegaly (70%), and splenomegaly (58%). Central nervous system dysfunction and hemorrhages were recorded in 35% and 20% of the patients, respectively. Platelet count and liver transaminase, ferritin, lactate dehydrogenase, triglyceride, and d-dimer levels were the sole laboratory biomarkers showing a percentage change of >50% between the pre-MAS visit and MAS onset. Evidence of macrophage hemophagocytosis was found in 60% of the patients who underwent bone marrow aspiration. MAS occurred most frequently in the setting of active underlying disease, in the absence of a specific trigger. Nearly all patients were given corticosteroids, and 61% received cyclosporine. Biologic medications and etoposide were given to 15% and 12% of the patients, respectively. Approximately one-third of the patients required admission to the intensive care unit (ICU), and the mortality rate was 8%. CONCLUSION: This study provides information on the clinical spectrum and current management of systemic JIA-associated MAS through the analysis of a very large patient sample. MAS remains a serious condition, as a sizeable proportion of patients required admission to the ICU or died.

Reduced intensity conditioning in allogeneic stem cell transplantation for AML with Down syndrome.

Allogeneic hematopoietic stem cell transplantation (HSCT) has not been widely used in patients with acute myeloid leukemia (AML) and Down syndrome (DS) due to fear of transplantation-related toxicity. A retrospective analysis of the outcome of allogeneic HSCT was conducted in 15 patients with AML and DS. The five patients transplanted with the reduced intensity conditioning (4 in complete remission (CR) and 1 in non-CR) had a significantly better survival rate than 10 patients transplanted with a conventional conditioning (4 in CR and 6 in non-CR) (3-year EFS (95% confidence interval): 80.0% (20.4-96.9%) vs. 10.0% (0.6%-35.8%), P = 0.039).

Clinical characteristics and outcomes of chédiak-Higashi syndrome: a nationwide survey of Japan.

BACKGROUND: Chédiak-Higashi syndrome (CHS) is a rare autosomal recessive disorder characterized by immunodeficiency, neurological dysfunction, and oculocutaneous albinism. Recently, several clinical CHS phenotypes have been reported. Here, we report results of a nationwide survey performed to clarify clinical characteristics and outcomes of CHS patients in Japan. METHODS: Questionnaires were sent to 287 institutions to collect data regarding CHS patients diagnosed between 2000 and 2010, including results of lysosomal trafficking regulator (LYST) gene analysis. Cytotoxicity and degranulation activity of cytotoxic T lymphocytes were analyzed in available patient samples. RESULTS: A total of 15 patients diagnosed with CHS were eligible for enrollment in this study. Of these, 10 (67%) had recurrent bacterial infections, five (33%) developed life-threatening hemophagocytic lymphohistiocytosis (HLH), and one patient had complicated malignant lymphoma. Hematopoietic stem cell transplantation (HSCT) was performed for six patients including three with HLH, and 10 of the enrolled patients have survived at the time of this writing. LYST analysis was performed for 10 patients; seven different mutations were detected in seven patients, whereas no mutation was identified in three patients. Cytotoxicity and degranulation activity were impaired in patients with and without LYST mutation. DISCUSSION: Results of this survey indicate that one or two patients with CHS were newly diagnosed each year in Japan. The incidence of HLH was not as high as expected. Mutations of genes other than LYST were suspected in some cases. We conclude that determining indication for HSCT for CHS patients should be based on genetic and cytotoxic analysis.

PBSCT is associated with poorer survival and increased chronic GvHD than BMT in Japanese paediatric patients with acute leukaemia and an HLA-matched sibling donor.

BACKGROUND: Peripheral blood stem cells (PBSC) may be used as an alternative to bone marrow (BM) for allogeneic transplantation. Since peripheral blood stem cell bank from unrelated volunteer donor has been started in Japan, use of PBSC allografts may be increased. Therefore we surveyed the outcomes of Japanese leukemia children after PBSC and BM transplantation. PROCEDURE: This retrospective study compared the outcomes of 661 children (0-18 years) with acute lymphoblastic leukaemia (ALL) or acute myeloid leukaemia (AML) who received their first allogeneic peripheral blood stem cell transplantation (PBSCT; n = 90) or bone marrow transplantation (BMT; n = 571) from HLA-matched siblings between January 1996 and December 2007. RESULT: Neutrophil recovery was faster after PBSCT than after BMT (ALL: P < 0.0001; AML: P = 0.0002), as was platelet recovery (ALL: P = 0.0008; AML: P = 0.0848). However, the cumulative incidence of chronic graft-versus-host disease (GvHD) was higher after PBSCT than after BMT (ALL: 26.0% vs. 9.9%, P = 0.0066; AML: 41.6% vs. 11.1%, P < 0.0001). The 5-year disease-free survival (DFS) was lower after PBSCT than after BMT for ALL (40.6% vs. 57.1%, P = 0.0257). The 5-year overall survival (OS) was lower after PBSCT than after BMT for ALL (42.4% vs. 63.7%, P = 0.0032) and AML (49.8% vs. 71.8%, P = 0.0163). Multivariate analysis revealed the use of PBSC was a significant risk factor for DFS and OS. PBSCT and BMT did not differ in relapse rate, acute GvHD for ALL and AML, or in DFS for AML. CONCLUSION: PBSC allografts in Japanese children engraft faster but are associated with poorer survival and increased chronic GvHD.

Rapid detection of intracellular p47phox and p67phox by flow cytometry; useful screening tests for chronic granulomatous disease.

Chronic granulomatous disease (CGD) is caused by defects of NADPH oxidase. The diagnosis of CGD can be made by analysis of NADPH oxidase activity, however, identification of the CGD subgroups is required before performing mutation analysis. The membrane-bound subunits, gp91phox and p22phox, can be quickly analyzed by flow cytometry, unlike the cytosolic components, p47phox and p67phox. We evaluated the feasibility of flow cytometric detection of p47phox and p67phox with specific monoclonal antibodies in two patients with p47phox deficiency and 7 patients with p67phox deficiency. Consistent with previous observations, p47phox and p67phox were expressed in phagocytes and B cells, but not in T or natural killer cells, from normal controls. In contrast, patients with p47phox and p67phox deficiency showed markedly reduced levels of p47phox and p67phox, respectively. These techniques will be useful to rapidly assess the expression of the cytosolic components, p47phox and p67phox, and represents important secondary screening tests for CGD.

Evaluation of the asparagine synthetase level in leukemia cells by monoclonal antibodies.

L-Asparaginase (ASNase) is important for the treatment of childhood acute lymphoblastic leukemia. ASNase sensitivity has been shown to correlate with the asparagine synthetase (ASNS) protein content in acute lymphoblastic leukemia cell lines. However, there have been few studies to determine ASNS protein levels in human leukemias, since no appropriate monoclonal antibody is available for such quantitative analysis. In this study, we report the generation of anti-ASNS monoclonal antibodies, which are applicable to flow cytometry and enzyme-linked immunosorbent assay. These monoclonal antibodies should provide a valuable tool for the quantification of ASNS protein level and estimation of ASNase-resistance in leukemia cells.

Extensive gene deletions in Japanese patients with Diamond-Blackfan anemia.

Fifty percent of Diamond-Blackfan anemia (DBA) patients possess mutations in genes coding for ribosomal proteins (RPs). To identify new mutations, we investigated large deletions in the RP genes RPL5, RPL11, RPL35A, RPS7, RPS10, RPS17, RPS19, RPS24, and RPS26. We developed an easy method based on quantitative-PCR in which the threshold cycle correlates to gene copy number. Using this approach, we were able to diagnose 7 of 27 Japanese patients (25.9%) possessing mutations that were not detected by sequencing. Among these large deletions, similar results were obtained with 6 of 7 patients screened with a single nucleotide polymorphism array. We found an extensive intragenic deletion in RPS19, including exons 1-3. We also found 1 proband with an RPL5 deletion, 1 patient with an RPL35A deletion, 3 with RPS17 deletions, and 1 with an RPS19 deletion. In particular, the large deletions in the RPL5 and RPS17 alleles are novel. All patients with a large deletion had a growth retardation phenotype. Our data suggest that large deletions in RP genes comprise a sizable fraction of DBA patients in Japan. In addition, our novel approach may become a useful tool for screening gene copy numbers of known DBA genes.