[Acute monoblastic leukemia with MLL/AF9 rearrangement which developed 18 months after myeloid sarcoma onset].

We describe a 36-month-old boy with acute monoblastic leukemia (AMoL M5a) and mixed-lineage leukemia (MLL)-AF9 rearrangement. At 18 months of age, he presented with swelling on the back of his hand that was considered to be an inflammatory change, but no hematological abnormalities were found. However, blasts with MLL-AF9 rearrangement were detected in biopsied tissue taken at the time and in peripheral blood samples taken 18 months later. These findings indicate that myeloid sarcoma with MLL-AF9 rearrangement may ultimately, though slowly, progress to AMoL.

Viridans streptococcal bacteremia-related encephalopathy in childhood with malignancy.

Viridans streptococcal bacteremia is a prognostic factor in pediatric patients with malignant disease accompanied by severe neutropenia. Here the authors describe 4 patients with viridans streptococcal bacteremia-related encephalopathy who showed serious complications, which included seizures and loss of consciousness. Therapy for relief of brain edema on seizures was started quickly, and included the administration of midazolam, dexamethasone, and mannitol with antimicrobial therapy. The treatment was successfully completed without sequelae. The authors registered 28 episodes of viridans streptococcal bacteremia in their hospital. The peak of serum C-reaction protein was higher in viridans streptococcal bacteremia patients with encephalopathy than in those without encephalopathy. The authors concluded that viridans streptococcal bacteremia can induce encephalopathy in pediatric patients with malignancy and that it is crucial to establish an accurate diagnosis and initiate therapy as soon as possible.

Chronic active Epstein-Barr virus infection with mosquito allergy successfully treated with reduced-intensity unrelated allogeneic bone marrow transplantation in a boy.

EBV-infected T-/NK cells play an important role in the pathogenesis of mosquito allergy, and the prognosis of most patients with mosquito allergy is poor without proper treatment. We describe a 13-yr-old boy who had CAEBV with mosquito allergy and was successfully treated with BMT from an unrelated donor after reduced-intensity preconditioning. Because combination chemotherapy failed to achieve CR, we performed unrelated BMT to reconstitute normal immunity and eradicate any residual EBV-infected cells. To reduce complications after BMT, we selected a reduced-intensity preconditioning regimen consisting of fludarabine, l-phenylalanine mustard, and antithymocyte Ig instead of a conventional myeloablative preconditioning. Although grade II acute GVHD developed, it was successfully controlled with immunosuppressive therapy. After 27 months, the patient has been well without any signs of CAEBV, and the EBV DNA has been undetectable with real-time PCR analysis. We conclude that RIST from the bone marrow of an unrelated donor is indicated for some patients who have CAEBV that is refractory to chemotherapy and who have no HLA-matched related donors or cord blood as a source of stem cells.

JAK2V617F mutation-positive childhood essential thrombocythemia associated with cerebral venous sinus thrombosis.

Myeloproliferative diseases (MPDs) in childhood are quite rare. Although pediatric and adult MPDs exhibit similar hematologic findings, JAK2V617F mutations and clonality status of MPDs in the DNA of neutrophils are evaluated less frequently in children than in adults. Increased incidence of venous thrombosis at uncommon sites is associated with JAK2V617F mutation in MPDs and thrombotic complications are more common in essential thrombocythemia (ET). Here, we describe 6-year-old girl with clonal myelopoiesis and JAK2V617F-positive ET associated with cerebral venous sinus thrombosis. To our knowledge, this is the first report of pediatric monoclonal and JAK2V617F-positive ET with cerebral venous sinus thrombosis.

[Treatment with voriconazole for invasive fungal infection during chemotherapy for leukemia: doses and plasma concentration of voriconazole in children].

We report on 4 children with invasive fungal infections complicated with leukemia who responded to voriconazole (VRCZ). In 3 children aged 1-6 years, the plasma VRCZ concentration was low and clinically ineffective after its administration at a dose of 4 mg/kg. Good plasma concentrations could be attained by increasing the dose to 5.3-12 mg/kg, and clinical effects were observed. In the other 13-year-old male, an adequate plasma concentration could be obtained after VRCZ administration at a dose of 4 mg/kg. Concerning adverse effects, transient visual abnormality developed in only 1 child. VRCZ may be effective and safe not only in adults but also in children with invasive fungal infection during chemotherapy for leukemia. Though the dose in adults is 3-4 mg/kg, the dose/weight in children should be higher because of the greater clearance. Since there are also individual differences in drug metabolism, the dose in children should be individually adjusted based on the plasma concentration.

[Long-term remission in an acute monoblastic leukemia patient with down syndrome after cord blood transplantation].

A 4-year-old boy with Down syndrome (DS) was diagnosed as having acute monoblastic leukemia (AML-M5a). Leukemic cells were CD33+, CD56+ and CD4+, with t(9;11) on cytogenetic analysis and MLL gene rearrangement. After 2 courses of induction therapy using an AML 99-Down protocol failed to obtain complete remission, the patient received cord blood transplantation from an HLA-matched donor (CBT) following a conditioning regimen comprising total body irradiation and cyclophosphamide. Only cyclosporin A was used for graft-versus-host disease prophylaxis. Stem cell transplantation may not be indicated for AML patient with DS in first remission, who display a high rate of life-threatening and fatal toxicity on therapy. This patient remained well controlled in complete remission for 4 years, representing a rare case of DS with chemotherapy-resistant AML successfully treated with a CBT.

Effect of excess estrogen on breast and external genitalia development in growth hormone deficiency.

BACKGROUND: The progress of sexual maturation and development in cases with growth hormone (GH) and insulin-like growth factor-I (IGF-I) deficiency is not well documented in females. CASE: We observed breast and genitalia development in a 2-year-old girl with GH deficiency following neonatal asphyxia; this girl later developed central precocious puberty. Markedly pigmented stimulated areolas and nipples without an apparent breast mound, and non-enlarged labia minora in the external genitalia were observed as features of sexual maturation in the patient. The hormonal condition was characterized by increased circulating estradiol levels and extremely low IGF-I levels. SUMMARY AND CONCLUSION: This case indicates that IGF-I is necessary for exerting the full effect of estrogen on the development of breasts and maturation of external genitalia.

I-131-Metaiodobenzylguanidine therapy with allogeneic cord blood stem cell transplantation for recurrent neuroblastoma.

Iodine-131-metaiodiobenzylguanidine (131I-MIBG) therapy combined with allogeneic cord blood stem cell transplantation (SCT) was used to treat a 4-year-old girl with recurrent neuroblastoma. The patient experienced relapse 2 years after receiving first-line therapies, which included chemotherapy, surgical resection, irradiation, and autologous peripheral SCT. Although 131I-MIBG treatment did not achieve complete remission, the size of the tumor was reduced after treatment. Based on our findings, we suggest that 131I-MIBG treatment with myeloablative allogeneic SCT should be considered as first-line therapy for high-risk neuroblastoma patients when possible.

Fluctuations in C-reactive protein in a hepatoblastoma patient with thrombocytosis.

We observed the changes in serum levels of interleukin 6 (IL-6) and C-reactive protein (CRP) in a patient with hepatoblastoma exhibiting thrombocytosis. The concomitant changes of IL-6 and CRP concentrations after the initiation of chemotherapy, in the absence of infection, suggested that the IL-6, which is synthesized in hepatoblastoma cells and induces thrombocytosis, also stimulated CRP production in the present case. IL-6 is thought to play an important role in thrombocytosis in hepatoblastoma.

Successfully treated acute lymphoblastic leukemia associated with craniopharyngioma.

The authors report a 2-year-old boy with acute lymphoblastic leukemia (ALL) associated with craniopharyngioma. To our knowledge, this is the first such report. Magnetic resonance imaging showed a suprasellar tumor, an apparent cystic lesion, whereas cerebral computed tomography confirmed that the tumor exhibited calcification. Without surgical intervention for the suprasellar tumor, we initiated chemotherapy for ALL. After 1 year of chemotherapy, complete remission was achieved, and partial resection and radiation therapy were performed on the suprasellar tumor. At 4 years after completing leukemia chemotherapy, the patient remains in complete ALL remission and has had no recurrence of craniopharyngioma.