Cord blood index predicts engraftment and early non-relapse mortality in adult patients with single-unit cord blood transplantation.

How to select optimal cord blood (CB) remains an important clinical question. We developed and validated an index of CB engraftment, the cord blood index (CBI), which uses three weighted variables representing cell doses and HLA mismatches. We modeled the neutrophil engraftment time with competing events by random survival forests for competing risks as a function of the predictors: total nucleated cells, CD34, colony-forming units for granulocytes/macrophages, and the number of HLA mismatches at the antigen and allele levels. The CBI defined three groups that had different neutrophil engraftment rates at day 30 (High, 83.7% [95% CI, 79.2-88.1%]; Intermediate, 77.0% [95% CI, 73.7-80.2%]; Low, 68.4% [95% CI, 63.6-73.2%]), platelet engraftment rates at day 60 (High, 70.4% [95% CI, 64.9-75.9%]; Intermediate, 62.3% [95% CI, 58.5-66.0%]; Low, 49.3% [95% CI, 44.2-54.5%]), and non-relapse mortality at day 100 (High, 14.1% [95% CI, 9.9-18.3%]; Intermediate, 16.4% [95% CI, 13.5-19.3%]; Low, 21.3% [95% CI, 17.1-25.5%]). This novel approach is clinically beneficial and can be adopted immediately because it uses easily obtained pre-freeze data of CB.

Digenic mutations in ALDH2 and ADH5 impair formaldehyde clearance and cause a multisystem disorder, AMeD syndrome.

Rs671 in the aldehyde dehydrogenase 2 gene (ALDH2) is the cause of Asian alcohol flushing response after drinking. ALDH2 detoxifies endogenous aldehydes, which are the major source of DNA damage repaired by the Fanconi anemia pathway. Here, we show that the rs671 defective allele in combination with mutations in the alcohol dehydrogenase 5 gene, which encodes formaldehyde dehydrogenase (ADH5FDH ), causes a previously unidentified disorder, AMeD (aplastic anemia, mental retardation, and dwarfism) syndrome. Cellular studies revealed that a decrease in the formaldehyde tolerance underlies a loss of differentiation and proliferation capacity of hematopoietic stem cells. Moreover, Adh5-/-Aldh2 E506K/E506K double-deficient mice recapitulated key clinical features of AMeDS, showing short life span, dwarfism, and hematopoietic failure. Collectively, our results suggest that the combined deficiency of formaldehyde clearance mechanisms leads to the complex clinical features due to overload of formaldehyde-induced DNA damage, thereby saturation of DNA repair processes.

Successful Treatment of Pediatric Refractory/Relapsed AML with KIR-Ligand-Mismatched Cord Blood Transplant after FLAG-IDA Reinduction Therapy with or without the GO Regimen.

Prognosis in pediatric patients with refractory/relapsed acute myeloid leukemia (AML) is grim, and there is no standard treatment for such patients. Combined treatment with intensive chemotherapy and gemtuzumab ozogamicin (GO), a monoclonal anti-CD33 antibody conjugated with calicheamicin, is useful as reinduction therapy in refractory/relapsed AML. Here, we describe three cases of pediatric refractory/relapsed AML that were successfully managed with FLAG-IDA (fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin), with or without GO, as reinduction therapy before a KIR-ligand-mismatched cord blood transplant. This strategy relies on the fact that killer cell immunoglobulin-like receptors (KIR) on cord blood natural killer (NK) cells recognize human leukocyte antigen (HLA) class I alleles, and that donor KIR-ligand incompatibility may be associated with lower incidence of relapse and improved survival in AML, as cells that lack these inhibitory HLA ligands can activate NK cells. All three patients are currently alive and have been disease-free for 24-65 months, although one patient developed severe sinusoidal obstructive syndrome (SOS). Thus, our strategy can result in excellent outcomes in pediatric patients with refractory/relapsed AML.

Killer-cell immunoglobulin-like receptor ligand mismatch cord blood transplantation in high-risk neuroblastoma.

BACKGROUND: The prognosis of high-risk neuroblastoma stage 4 with bone marrow metastasis, MYCN amplified, or refractory neuroblastoma is poor. To date, no standard treatment has been established. In four selected cases, we challenged the killer-cell immunoglobulin-like receptor ligand mismatch cord blood transplantation in graft-versus-host disease (GVHD) with reduced-intensity conditioning. METHODS: Prior to this study, conventional chemotherapy, autologous peripheral blood stem cell transplantation with high-dose chemotherapy (busulfan and melphalan), surgery and radiation therapy were completed in every case. The status before cord blood transplantation in two cases was not complete remission (CR) and in the others it was CR. The primary site was the mediastinum, two adrenal glands and a retroperitoneum, respectively. Three patients had bone and bone marrow metastasis and one had MYCN amplification. In all cases, international neuroblastoma pathology classification was unfavorable histology. All patients were >2 years of age. RESULTS: Relapse occurred only in one patient 17 months after the last transplantation, and the other three patients maintained disease-free survival for 74, 36, and 24 months, respectively. In one case of relapse the disease could be controlled by conventional chemotherapy. Except one, all patients had no severe complications, such as acute or chronic GVHD. One patient had gastric antral vascular ectasia and hemorrhagic cystitis. CONCLUSION: This strategy might be feasible and should be investigated for efficacy in the future. No definite conclusion can be made, however, due to the very small number of patients. Further prospective studies are required to determine its efficacy.

Gastric antral vascular ectasia in a pediatric patient with neuroblastoma who underwent tandem stem cell transplantation.

Gastric antral vascular ectasia (GAVE) is an angiodysplastic disorder, which causes severe and prolonged gastric bleeding. Although GAVE has been described in adult patients treated with hematopoietic stem cell transplantation (HSCT), a few cases involving pediatric patients have also been reported. A 5-year-old boy with neuroblastoma (NB) developed severe hematemesis after undergoing tandem HSCT, i.e. autologous peripheral blood stem cell transplantation (auto-PBSCT), followed by allogeneic cord blood transplantation (allo-CBT). The patient suffered oral feeding difficulties because of the effects of chemotherapy and an unbalanced diet. Intravenous Busulfan (ivBU) was used as a conditioning regimen for the auto-PBSCT. The diagnosis of GAVE was made based on endoscopy of the upper gastrointestinal tract on day 31 after the allo-CBT. Argon plasma coagulation (APC) was performed twice, and the complete resolution of GAVE was confirmed by an endoscopic re-evaluation, conducted on day 87. GAVE in this case might have been associated with ivBU treatment. Atrophy of the gastric mucosa due to loss of appetite might also have contributed to GAVE. NB was treated using high-doses of alkylating agents, such as BU. Such treatment can cause significant mucositis of the oral cavity as well as vascular lesions and is associated with GAVE. Therefore, GAVE should be considered when gastrointestinal bleeding occurs in NB patients treated with HSCT. APC might be effective against HSCT-GAVE.

Prophylactic recombinant thrombomodulin treatment prevents hepatic sinusoidal obstruction syndrome in high-risk pediatric patients that undergo hematopoietic stem cell transplants.

Hepatic SOS is a potentially life-threatening complication of conditioning for allogeneic HSCT. rTM is a new drug for treating DIC. We report our experience of the use of rTM as a prophylaxis against SOS in high-risk pediatric patients that underwent HSCT. We evaluated the cases of 19 pediatric hematology and oncology patients who underwent HSCT at our institution between 2007 and 2016. The patients who received HSCT after 2012 (n = 8) were treated with rTM as a prophylaxis against SOS together with UDCA and LMWH, whereas the others (n = 11) were only treated with UDCA and LMWH. Although SOS occurred by post-HSCT day 35 in 3 (27%) patients in the control group, SOS was not seen in the rTM group. Two of the former three patients suffered severe SOS, and one died of the condition. The mean peak level of PAI-1 (a marker of endothelial damage) was significantly lower in the rTM group. rTM appears to be a safe prophylaxis for SOS. The present findings suggest that prophylactic rTM after HSCT might help to prevent SOS.

Clinical features of, and association of bladder ultrasound and uroflowmetry with, overactive bladder recovery period in children.

BACKGROUND: Overactive bladder (OAB) is a symptomatic syndrome defined by urinary urgency, usually accompanied by increased urination frequency and nocturia, with or without urinary incontinence. The prevalence of pediatric OAB in 5-13 year olds is as high as 16.6%, but the pathophysiology and epidemiology have not been sufficiently elucidated. METHODS: We retrospectively reviewed medical records in 117 children with OAB aged between 5 and 15 years during the years 2012-2016. At initial presentation, abdominal ultrasound and uroflowmetry were performed, and behavioral modifications, such as timed voiding, and constipation therapy were initiated. If there was no response after 4 weeks, antimuscarinic treatment was added. We evaluated the clinical features of OAB and factors related to the recovery period, which was defined as the period from the start of behavioral modifications to cure. RESULTS: The average recovery period was 11.9 ± 9.73 months. There was no significant difference in the recovery period according to age, gender, percentage of urination frequency, nocturnal enuresis, or constipation. The recovery period was significantly shorter in the group with bladder wall thickness ≥5 mm than with bladder wall thickness <5 mm. Children with a tower-shaped curve on uroflowmetry had a significantly shorter recovery period than those with a bell-shaped curve. CONCLUSIONS: Bladder wall thickness and uroflow curve shape are related to the recovery period of pediatric OAB.

[Initial presentation of lymphoblastic crisis in a pediatric chronic myelogenous leukemia patient].

A 9-year-old girl was referred to our hospital because of facial palsy. Both physical and blood examination revealed hepatosplenomegaly and leukocytosis, respectively. A bone marrow examination demonstrated marked hypercellularity involving myeloblasts and lymphoblasts. Based on these results, we suspected mixed phenotype acute leukemia. However, her leukemic blasts expressed B-cell antigens, and a chromosomal analysis of her bone marrow cells revealed the following karyotype: 46, XX, t (9;22) (q34;q11.2). All her neutrophils were positive for the breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1 fusion protein. Based on these findings, she was diagnosed with a lymphoblastic crisis of chronic myelogenous leukemia (CML). Combined chemotherapy, involving imatinib, resulted in complete molecular remission. She received cord blood transplant (CBT) during the first complete remission; she is alive and has not suffered a relapse since two years after the CBT. The sudden onset of a blastic crisis in pediatric CML is rare, and it may be difficult to distinguish such cases from de novo Ph-positive leukemia. For diagnostic purposes, it is essential to consider a patient's clinical course and blood test results.

Wiskott-Aldrich syndrome that was initially diagnosed as immune thrombocytopenic purpura secondary to a cytomegalovirus infection.

Wiskott-Aldrich syndrome is a rare X-linked recessive disease resulting from variations in the WAS gene. Wiskott-Aldrich syndrome is sometimes difficult to differentiate from immune thrombocytopenic purpura. A 2-month-old boy was admitted to our hospital for purpura and thrombocytopenia. His mean platelet volume was reported to be normal. Treatment with intravenous immunoglobulins failed to improve the patient's platelet count. Subsequently, an acute cytomegalovirus infection was confirmed by serological testing and antigenemia. The patient was diagnosed with immune thrombocytopenic purpura secondary to a cytomegalovirus infection. However, based on the patient's clinical course and the refractoriness of his condition, Wiskott-Aldrich syndrome was strongly suspected. Through direct sequencing of the genomic DNA of the Wiskott-Aldrich syndrome protein (WASP) gene, we identified a novel missense mutation in exon 3 of the patient's WASP gene (c. 343 C>T, p. H115T), and the patient was diagnosed with Wiskott-Aldrich syndrome at 3 months after onset. Children with Wiskott-Aldrich syndrome are often initially diagnosed with immune thrombocytopenic purpura, which can lead to inappropriate treatment and delays to life-saving definitive therapy. Our findings imply that Wiskott-Aldrich syndrome should be considered as a differential diagnosis in cases of refractory immune thrombocytopenic purpura combined with a cytomegalovirus infection.

Increased expression of interleukin-17 is associated with macrophages in chronic immune thrombocytopenia.

Objectives: Interleukin-(IL-)17-mediated cells contribute to the imbalance of cellular immunity in the pathogenesis of immune thrombocytopenia (ITP). We examined samples of bone marrow (BM) clots to determine if IL-17-mediated immunological changes involve the BM and to identify clinical predictors of treatment response. Methods: We enrolled 33 patients with chronic ITP. BM clots were obtained before treatment and stained with the following markers: CD3, CD4, CD8, CD20, CD25, CD68, CD163, and IL-17. Pathological findings and clinical information, including laboratory data, were compared between the patients and 11 control subjects and between IL-17-high and -low-expression groups. Results: Univariate analysis revealed increased cells expressing CD68, CD163, and IL-17 in the patients with ITP than in the control subjects (P = 0.02, 0.001, and 0.001, respectively). The expression of both CD68 and CD163 showed correlation with IL-17 expression (r = 0.60 and 0.48, respectively). Responses to Eltrombopag were better in the IL-17-low-expression group than in the IL-17-high-expression group (P = 0.056). Conclusions: Macrophages and monocytes were associated with IL-17 expression in patients with ITP. We demonstrated that ITP is associated with IL-17-expressing monocytes/macrophages and might be more difficult to treat.

Fludarabine, cytarabine, granulocyte colony-stimulating factor and idarubicin for relapsed childhood acute myeloid leukemia.

BACKGROUND: The combination of fludarabine (Flu), high-dose cytarabine (Ara-C) and granulocyte colony-stimulating factor (G-CSF; FLAG), with anthracyclines has become standard chemotherapy for refractory acute myeloid leukemia (AML) in European children and adults. To clarify the efficacy and the safety of FLAG-idarubicin (IDA) for children prospectively, we planned a multicenter phase II study (AML-R11) by the Japanese Pediatric Leukemia/Lymphoma Study Group. METHODS: Patients with AML aged between 2 and 20 years old, who had the first bone marrow (BM) relapse or induction failure, were enrolled. The FLAG-IDA regimen consisted of Flu 30 mg/m2 for 5 days, Ara-C 2 g/m2 for 5 days, G-CSF (lenograstim) 5 µg/kg for 6 days and IDA 10 mg/m2 for 3 days. The primary endpoint was remission rate after therapy. RESULTS: Due to drug supply issues, the trial was suspended after the inclusion of seven eligible patients. There were six cases of early relapse within 1 year of the first remission. All seven patients completed the therapy and no early death was observed. Hematological toxicity was common, and one patient developed grade 4 non-hematological toxicity of bacterial meningitis. Although only one patient with late relapse achieved complete remission, minimal residual disease was positive on both flow cytometry and Wilms' tumor 1 mRNA. Two patients were alive in remission following hematopoietic stem cell transplantation, whereas the other five patients died of either the disease or treatment-related causes. CONCLUSION: FLAG-IDA might be tolerable for children with refractory AML although the efficacy should be further investigated.

Increased renal concentrating ability after long-term oral desmopressin lyophilisate treatment contributes to continued success for monosymptomatic nocturnal enuresis.

OBJECTIVES: To investigate renal concentrating ability after long-term fast-melting oral desmopressin lyophilisate treatment in children with monosymptomatic nocturnal enuresis. METHODS: The present retrospective study involved 58 children (43 boys, 15 girls; aged 6-12 years) with nocturnal enuresis receiving oral desmopressin lyophilisate. After treatment for 4 weeks with a complete response, patients were placed on a reduced dose of 120 µg on alternate days. Moring urine osmolality was measured using urine samples obtained after medication and non-medication dry nights. Patients who experienced ≥1 wet nights/month during alternate-day oral desmopressin lyophilisate treatment or within 6 months after its cessation were assigned to the relapse group, whereas those who experienced <1 wet night/month were assigned to the continued success group. RESULTS: The continued success and relapse groups included 41 and 17 patients, respectively. The mean duration of treatment was 18.5 and 18.3 months in the continued success group and relapse group, respectively. There was no significant difference in morning urine osmolality after medication nights between the continued success and relapse groups; however, morning urine osmolality after non-medication nights was significantly higher in the continued success group than in the relapse group (P < 0.0001). Similarly, nocturnal urine volume was significantly higher in the relapse group than in the continued success group (P = 0.046). CONCLUSIONS: These results suggest that patients receiving long-term oral desmopressin lyophilisate treatment develop increased nocturnal renal concentrating ability, which results in sustained dryness even after treatment cessation.

Successful low-dose radiotherapy treatment for Kasabach-Merritt syndrome.

Kasabach-Merritt syndrome (KMS) is characterized by hemangioma associated with life-threatening thrombocytopenia, and is a consumptive coagulopathy. Although treatments available include corticosteroids, α-interferon, vincristine, and surgery, response may be unsatisfactory, and the mortality rate remains at approximately 30%. Although radiotherapy has been used effectively for KMS, it may cause growth retardation and secondary malignancy. We report a case of KMS in which hemangioma of the left thigh was successfully treated with low-dose radiotherapy (6 Gy in six fractions, weekly) after failure of corticosteroid therapy. No significant late effects due to the radiotherapy were noted at 5 year follow up. Thus, low-dose radiotherapy remains an important treatment method for KMS when patients fail to respond to other treatments.

Residual disease detected by multidimensional flow cytometry shows prognostic significance in childhood acute myeloid leukemia with intermediate cytogenetics and negative FLT3-ITD: a report from the Tokyo Children's Cancer Study Group.

Residual disease (RD) after induction chemotherapy may predict clinical outcome in acute myeloid leukemia (AML). In the present study, we investigated the prognostic significance of RD detected by multidimensional flow cytometry (MDF) among 34 children treated for AML in a clinical trial (JPLSG AML-05) in Japan. Bone marrow samples were analyzed at the points of the end of the first induction course (BMA-1) and second induction course (BMA-2) by MDF. RD was evaluated by detecting the immature cells showing abnormal antigen expression pattern; CD34(+), CD15(+), CD7(+). Thirteen (39.4 %) of 34 patients at BMA-1 and 8 (27.6 %) of 34 at BMA-2 had RD levels ≥0.1 %. There was no significant difference in 3y-EFS and 3y-OS between patients with RD levels ≥0.1 % and those with RD levels <0.1 % (53.8 versus 70.0 %, P = 0.30 and 50.0 versus 66.7 %, P = 0.27, respectively). However, IR cytogenetics and negative FLT3-ITD patients with RD levels ≥0.1 % exhibited significantly lower 3y-EFS and 3y-OS than those with RD levels <0.1 % (33.3 versus 83.3 %, P = 0.02 and 20.0 versus 76.9 %, P = 0.005, respectively). Our study suggests that RD shows prognostic relevance in pediatric patients with IR cytogenetics and negative FLT3-ITD AML.

Use of LightCycler mutation analysis to detect type II adenine phosphoribosyltransferase deficiency in two patients with 2,8-dihydroxyadeninuria.

Recently, a number of methods have been devised for detection of mutations in the field of molecular genetics. The LightCycler system has been used for rapid PCR, while simultaneously quantifying and analyzing the amplification results. We tried to apply the LightCycler system to detect APRT*J allele mutations in two families including two children with 2,8-dihydroxyadenine urolithiasis. The first patient was a 3-year-old girl who presented with left flank pain. The second patient was a 2-year-old girl who presented with complaints of sudden dysuria. The spectrophotometric analysis of the stone fragments of both patients revealed an absorption spectrum for 2,8-DHA. We used the LightCycler system to detect APRT*J mutation. The first patient was homozygous for APRT*J/APRT*J and the second patient was compound heterozygous for APRT*J/APRT*Q0. The genetic diagnosis of APRT deficiency using this system may be useful not only as a diagnostic test for infants with known 2,8-DHA, but also as a screening of infants with a suspicion of urolithiasis. We believed that the LightCycler system still is an important means of identifying APRT*J mutation.

No impact of high-dose cytarabine and asparaginase as early intensification with intermediate-risk paediatric acute lymphoblastic leukaemia: results of randomized trial TCCSG study L99-15.

The Tokyo Children's Cancer Study Group conducted a randomized controlled study to evaluate the effect of experimental early intensification using high-dose cytarabine and L-asparaginase in paediatric intermediate-risk (IR) acute lymphoblastic leukaemia (ALL). A total of 310 IR ALL patients were randomized to receive either experimental early intensification (n = 156) or standard early intensification including standard-dose cytarabine arm (n = 154) after induction therapy. The experimental arm consisted of high-dose cytarabine and L-asparaginase, while the standard arm consisted of standard-dose cytarabine, oral 6-mercaptopurine and cyclophosphamide. The probabilities of event-free survival at 8 years in the experimental and standard arms were 72·3 ± 3·7% and 77·5 ± 3·5%, respectively (P = 0·32). The 8-year overall survival rates for these two arms were 85·0 ± 3·0% and 86·9 ± 2·8%, respectively (P = 0·72). The frequency of infectious events was significantly higher in the experimental arm (66·4%) than in the standard arm (24·6%) (P < 0·001). In conclusion, experimental early intensification including high-dose cytarabine followed by L-asparaginase had no advantage over standard early intensification in paediatric IR ALL patients.

Appropriate dose reduction in induction therapy is essential for the treatment of infants with acute myeloid leukemia: a report from the Japanese Pediatric Leukemia/Lymphoma Study Group.

Infants (<1 year old) with acute myeloid leukemia (AML) are particularly vulnerable to intensive cytotoxic therapy. Indeed, the mortality rate was high among infants enrolled in the Japanese Pediatric Leukemia/Lymphoma Study Group AML-05 study, which prompted us to temporarily suspend patient enrollment and amend the protocol. Forty-five infants with AML were enrolled. For patients aged <2 years, drug doses were adjusted for body weight. Following the protocol amendments, doses for infants were reduced by a further 33 % in the initial induction course. Six infants died during the induction phase (including five early deaths), mainly due to pulmonary complications. The 3-year probability of overall survival (pOS) in all 45 infants [55.9 %, 95 % confidence interval (CI) 37.9-70.6 %] was significantly lower than that of patients aged 1 to <2 years (77.0 %, 95 % CI 62.7-86.3 %) and those aged ≥2 years (74.7 %, 95 % CI 69.2-79.4 %) (P = 0.037), mainly due to the higher non-relapse mortality rate in infants. No early deaths occurred after the protocol amendments, and the 3-year pOS of the 17 infants enrolled thereafter was 76.4 % (95 % CI 48.8-90.4 %). In conclusion, appropriate dose reduction is essential to avoid early deaths when treating infants with AML.

[A case of focal segmental glomerulosclerosis with nephrotic syndrome after hematopoietic stem cell transplantatation for aplastic anemia].

We report a case of pediatric severe aplastic anemia (SAA), where the patient underwent allogenic bone marrow transplantation (BMT) from an HLA mismatched family donor and developed focal segmental glomerulosclerosis (FSGS). An 11-year-old girl, who had SAA, was admitted to our hospital in 200X. Complete remission was not attained after immunosuppressive therapy with rabbit-antithymocyte globulin, prednisolone (PSL), and cyclosporine A (CsA). Eight months after being diagnosed with SAA, she underwent an allogenic BMT from her mother. We used a combination of 2-Gy total body irradiation, fludarabine, and cyclophosphamide as a preparative regimen prior to the BMT. CsA and PSL were used as prophylaxis against GVHD. Since the BMT did not lead to successful engraftment, the patient required two peripheral blood stem cell transplantations (PBSCT). Engraftment was sustained and no acute or chronic GVHD was observed. Six months after the first BMT, she developed clinical nephrotic syndrome despite the continuous PSL and CsA treatments. Renal biopsy revealed a total of 12 glomeruli, one of which showed segmental sclerosis. Electron microscopy revealed diffuse effacement of the foot processes. These findings were consistent with FSGS, and she was treated with mycophenolate mofetil (MMF) in combination with PSL instead of CsA, which greatly reduced her proteinuria. In general, the most common type of nephropathy after HSCT is GVHD-related nephrotic syndrome, and the most common pathological finding is membranous nephropathy or minimal change. FSGS without GVHD after HSCT, such as that observed in our case, is rare. In this case, the renal damage appears to have been caused by the effect of circulating permeability factors with immunity change after HSCT. This case demonstrates the importance of renal biopsy as a guide to determine the extent of renal damage and as an aid to determine the possible response to therapy.