Administration of platelet concentrates suspended in bicarbonated Ringer's solution in children who had platelet transfusion reactions.

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.

Factors related to allergic transfusion reactions and febrile non-haemolytic transfusion reactions in children.

BACKGROUND AND OBJECTIVES: Allergic transfusion reactions (ATRs) and febrile non-haemolytic transfusion reactions (FNHTRs) are the two major types of transfusion-related adverse reactions (TRARs). Although prestorage leucocyte reduction and diversion of the first aliquot of blood (LR/D) could reduce FNHTRs and bacterial contamination in adult transfusion, ATRs are still problematic. In addition, there is little information about TRARs in paediatric population. MATERIALS AND METHODS: We conducted a single-centre retrospective analysis of all transfusions, except washing products, and TRARs for 153 months to evaluate related factors such as delivery of treatment and the characteristics of recipients. RESULTS: Most TRARs were FNHTRs and/or ATRs in children. In delivering blood products with LR/D, the frequencies of not only FNHTRs but also ATRs were significantly reduced with both platelet concentrates (PCs) and red cell concentrates (RCCs). TRARs of fresh-frozen plasma were infrequent in children. In addition, even after the introduction of LR/D, ATRs were significantly more frequent in patients with primary haematological and malignant diseases who received PCs and RCCs, older patients who received PCs and patients who received frequent RCCs. CONCLUSION: These results suggest that leucocytes or mediators from leucocytes are underlying cause of ATRs in addition to FNHTRs in children. Furthermore, particular characteristics of patients would be other risk factors for ATRs.

Safety, tolerability, and feasibility of antifungal prophylaxis with micafungin at 2 mg/kg daily in pediatric patients undergoing allogeneic hematopoietic stem cell transplantation.

INTRODUCTION: Micafungin (MCFG) is used for the prophylaxis of invasive fungal disease (IFD) after allogeneic hematopoietic stem cell transplantation (HSCT). However, the safety, efficacy, or optimal dosage/blood levels as prophylaxis is uncertain in pediatric HSCT-patients. METHODS: We prophylactically administered MCFG at 2 mg/kg once daily to 38 children and adolescents undergoing allogeneic HSCT. RESULTS: During MCFG prophylaxis, infusion reactions or adverse events (grades 2-5) related to MCFG use were not found in all the patients. Thus, MCFG prophylaxis was not discontinued and other antifungal agents were not added except for 2 patients in whom probable or possible IFDs developed (completion rate, 94.7 %). To elucidate the influence of HSCT-related complications/drugs on blood concentration of MCFG, we determined the plasma trough and peak levels in 13 and 10 among 38 patients, respectively. The mean trough and peak levels were 3.04 ± 1.21 µg/mL (569 samples) and 9.63 ± 3.62 µg/mL (44 samples), respectively. The peak levels were moderately correlated to the trough levels (R (2) = 0.466). In a patient, the trough level of MCFG transiently increased up to 10.21 µg/mL during hepatic dysfunction due to acute graft-versus-host disease. The MCFG trough levels strongly correlated with T-Bil value (R (2) = 0.894). There was no relationship between the trough levels of MCFG and the circulating concentrations of tacrolimus (R (2) = 0.040). Additionally, MCFG levels were not influenced by treatment with cyclophosphamide or corticosteroids. CONCLUSIONS: Prophylaxis with MCFG at 2 mg/kg once daily may be safe, tolerable, and feasible in pediatric HSCT-patients.

Successful ganciclovir therapy in a patient with human herpesvirus-6 encephalitis after unrelated cord blood transplantation: usefulness of longitudinal measurements of viral load in cerebrospinal fluid.

BACKGROUND: There have been no reports of human herpesvirus-6 (HHV-6) encephalitis treatment based on both HHV-6 DNA load and the antiviral agent's concentration in the cerebrospinal fluid (CSF). PATIENT: A 20-year-old male with a hematological malignancy developed HHV-6 encephalitis 15 days after unrelated cord blood transplantation (UCBT). He had fever, chest pain, memory impairment, and insomnia. His CSF showed no increased cell counts, but the amount of HHV-6 DNA was elevated to 2.0 × 10(6) copies/ìgDNA. Magnetic resonance imaging (MRI) of the head revealed abnormal high-intensity signals in the left limbic system on T2-weighted and diffusion-weighted images. Intravenous administration of ganciclovir (GCV) was initiated at 5 mg/kg every 12 h on day 18, and was continued until day 137. The amount of HHV-6 DNA in the plasma became undetectable on day 25. The HHV-6 load in the CSF decreased to 1.5 × 10(3) copies/ìgDNA on day 32, and reached undetectable levels on day 53. The mean concentration of GCV 1 h after an infusion of 5 mg/kg was 4.12 mg/mL in plasma and 0.7 mg/mL in CSF. The chest pain and insomnia disappeared on days 35 and 47, respectively. Memory defects recovered up to day 85. CONCLUSION: Serial quantification of HHV-6 DNA in CSF may be useful for successful treatment with GCV in post-transplant HHV-6 encephalitis.

Differences in muscle and fat accretion in Japanese Black and European cattle.

The development of different muscles and adipose tissues during growth was investigated in commercial Japanese Black (JB) cattle and compared with breeds of the largest variation to be found in Europe. Animals, reared under typical conditions for Japanese and European beef production systems, gained similar body weights but different carcass composition at 24months of age. The carcass of JB contained more adipose tissue and the least proportion of muscle. The longissimus muscle of JB developed extraordinary amounts of 23.3% intramuscular fat (IMF) at 24months of age, compared from 0.6% to 4.7% in European breeds. The relationships between IMF content in the longissimus muscle and different adipose tissue weights indicate that a large amount of "waste fat" is accreted with every percent of IMF. However in JB, the good ability of IMF deposition is associated with relatively least development of "waste fat", as a result of unique breed characteristics combined with special feeding system.

Dynamic DNA methylation change in the CpG island region of p15 during human myeloid development.

We examined the kenetics of p15 methylation and expression during myeloid development. We treated human cord blood CD34+ cells with either GM-CSF alone or in combination with stem cell factor and followed methylation at this locus using bisulfite genomic sequencing. CD34+ cells were found to be either fully methylated or completely unmethylated at 27 CpG dinucleotide sites in exon 1 and at 18 CpG sites in the promoter region of the p15 gene. A time-course study showed that the percentage of the allelic methylation of p15 CpG island increased to approximately 50% to 60% until 7 days after cytokine stimulation, then decreased to less than 10% after 21 days. The methylation was also observed in bone marrow CD34+ cells exposed to GM-CSF. p15 expression varied inversely with methylation. Expression was negligible or at low levels until 14 days, after which it increased substantially. The frequency of myeloid colony-forming cells in the progeny decreased and myeloid-specific markers increased in the later stages. Based on our observations on cells grown with GM-CSF and 5-aza-2'-deoxycytidine, DNA methylation of the p15 promoter region CpG island appears to be associated with proliferation rather than differentiation of normal human myeloid progenitors.

Chromosomal change during 6-mercaptopurine (6-MP) therapy in juvenile myelomonocytic leukemia: the growth of a 6-MP-refractory clone that already exists at onset.

Among 11 JMML children, two had an abnormal karyotype, and nine had a normal karyotype at onset. In one patient with trisomy 8 and four patients with a normal karyotype, a new clone with an aberrant karyotype emerged 1-14 months after 6-mercaptopurine (6-MP) therapy as shown by G-banding analyses. Fluorescence in situ hybridization disclosed that an abnormal clone existed in approximately 3-6% of bone marrow cells at onset or before 6-MP therapy in all the four cases examined, and increased to approximately 12-90% during the treatment. In culture with granulocyte-macrophage colony-stimulating factor, cytogenetically abnormal clones that proliferated during 6-MP therapy possessed significantly less sensitivity to the antimetabolite, compared with cells that decreased in numbers after the therapy. A PTPN11 mutation was detected in all of granulocyte-macrophage colonies irrespective of karyotypic aberration in one patient, whereas approximately 80% of erythroid colonies and 20% of mixed colonies possessed neither a PTPN11 mutation nor chromosomal abnormalities. The appearance of chromosomal aberrations shown by G-banding during 6-MP therapy in some JMML cases may result, in part, from the growth of a 6-MP-refractory clone that already exists at onset. It is possible that treatment with 6-MP promotes progression of the disease.

Thrombopoietin enhances neutrophil production by bone marrow hematopoietic progenitors with the aid of stem cell factor in congenital neutropenia.

We examined the effects of granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), and thrombopoietin (TPO), alone or in combination, on the generation of neutrophils by bone marrow (BM) cells from three patients with severe congenital neutropenia (SCN) through the use of a serum-deprived liquid culture system. Synergistic effects of G-CSF and SCF on the neutrophil production by BM CD34+CD38+c-kit+ cells were observed in SCN patients as well as in normal controls. The addition of TPO to the culture containing G-CSF and SCF further augmented the growth of neutrophils in the two groups. Single-cell culture experiments revealed that the three-factor combination caused increases in both the number and size of neutrophil colonies compared with G-CSF + SCF in normal BM cells, whereas only a significant increment in the colony size was observed in SCN patients. Even in the presence of SCF or SCF + TPO, the concentrations of G-CSF necessary for the substantial production of neutrophils by CD34+CD38+c-kit+ cells were higher in two patients compared with the levels obtained by normal control cells. In addition, TPO did not accelerate the maturation of neutrophilic cells supported by G-CSF + SCF. When BM CD34+CD38-c-kit+ cells were targeted, the addition of TPO to the culture containing G-CSF and SCF was required for significant neutrophil colony growth in the two groups. These results suggest that TPO enhances the G-CSF-dependent neutrophil production with the aid of SCF in this disorder.

In vitro expansion of CD34(+)CD38(-) cells under stimulation with hematopoietic growth factors on AGM-S3 cells in juvenile myelomonocytic leukemia.

Using serum-containing culture, we examined whether AGM-S3 stromal cells, alone or in combination with hematopoietic growth factor(s), stimulated the proliferation of CD34(+) cells from patients with juvenile myelomonocytic leukemia (JMML). AGM-S3 cells in concert with stem cell factor plus thrombopoietin increased the numbers of peripheral blood CD34(+) cells to approximately 20-fold of the input value after 2 weeks in nine JMML patients with either PTPN11 mutations or RAS mutations, who received allogeneic hematopoietic transplantation. Granulocyte-macrophage colony-stimulating factor (GM-CSF) also augmented the proliferation of JMML CD34(+) cells on AGM-S3 cells. The expansion potential of CD34(+) cells was markedly low in four patients who achieved spontaneous hematological improvement. A large proportion of day-14-cultured CD34(+) cells were negative for CD38 and cryopreservable. Cultured JMML CD34(+)CD38(-) cells expressed CD117, CD116, c-mpl, CD123, CD90, but not CXCR4, and formed GM and erythroid colonies. Day-7-cultured CD34(+) cells from two of three JMML patients injected intrafemorally into immunodeficient mice stimulated with human GM-CSF after transplantation displayed significant hematopoietic reconstitution. The abilities of OP9 cells and MS-5 cells were one-third and one-tenth, respectively, of the value obtained with AGM-S3 cells. Our culture system may provide a useful tool for elucidating leukemogenesis and for therapeutic approaches in JMML.

Flow cytometric studies of the binding of monoclonal antibodies OKT3, OKT4 and OKT8.

The binding of monoclonal antibodies (OKT3, OKT4 and OKT8) to human T cells was investigated by flow cytometry. A flow cytometer was calibrated with standard fluorescence microspheres, which permitted quantitation of the number of bound antibody molecules. Considerable care was taken to perform the flow cytometric assay at a constant temperature and the effect of temperature on the binding reaction was examined. The binding of OKT3, OKT4 and OKT8 exhibited saturation kinetics. The maximum binding varied with temperature. Kinetic analysis according to the Hill equation revealed that the value of the Hill coefficient for OKT3 changed from 1.8 to 1.0 when the temperature was raised from 12 degrees C to 36 degrees C, whereas the corresponding values for OKT4 and OKT8 did not vary with temperature. Thermodynamic functions obtained from the Van't Hoff plot showed that the binding of OKT3 was exothermic whereas the binding of OKT4 and OKT8 were endothermic.

Production of prostaglandins E1 and E2 by adult human red blood cells.

We showed that human adult red blood cells (RBCs) produce prostaglandin E1 (PGE1) and E2 (PGE2). RBCs that were mechanically stressed in the presence of extracellular Ca2+ by being injected rapidly through a fine needle produced PGE1 and PGE2 within 30 min after this mechanical stress. The amounts of PGE1 and PGE2 produced by 1 x 10(9) mechanically stressed RBCs were approximately 50 pg and 100 pg, respectively, which were determined in the cytosolic fraction from sonicated RBCs using a competitive enzyme immunoassay method. A Western blot analysis using anti-cyclooxygenase-2 antibody revealed a band at the 70-kDa position in the samples from RBCs producing PGE1 and PGE2. Treatment with 10 micrograms/mL indomethacin completely inhibited the productions of PGE1 and PGE2. The present results may indicate a new role of RBCs in microcirculation.

Computerized tomography angiography of ruptured cerebral aneurysms: factors affecting time to maximum contrast concentration.

OBJECT: This study was conducted to assess the diagnostic value of three-dimensional computerized tomography (3-D CT) angiography in demonstrating cerebral aneurysms in 42 consecutive patients presenting with acute subarachnoid hemorrhage (SAH). METHODS: To obtain the volume data for selective visualization of the cerebral arteries without enhancement of the venous system, the time delay was established between the injection of contrast medium and the start of scanning by using two different methods. The circulation time was calculated with Schad's formula in the first 13 cases, but the results were not satisfactory. In the 29 subsequent cases the time delay was established using a single-level dynamic CT prescan. The dynamic prescan demonstrated the statistical differences in peak time with regard to patient age, SAH grade, and the postresuscitation state after cardiopulmonary arrest. The 3-D CT angiograms were generated from the volume data by using a voxel transmission method. Computerized tomography angiography obtained after optimally adjusted time delay demonstrated the contour of the cerebral arteries in 97% of cases, and aneurysms were detected in 93%. Enhancement of the cavernous sinus and major cortical veins was avoided. Even in patients who suffered cardiopulmonary arrest, images of the major arteries were clearly demonstrated after resuscitation. CONCLUSIONS: In an emergency situation, CT angiography with a dynamic prescan may be an alternative to magnetic resonance angiography or digital subtraction angiography in the diagnosis of ruptured aneurysms. This modality would also be useful for the precise assessment of small aneurysms, blebs, and aneurysms adjacent to the cavernous sinus.

Spontaneous disappearance and reappearance of a ruptured cerebral aneurysm: one case found in a group of 33 consecutive patients with subarachnoid hemorrhage who underwent repeat angiography.

The spontaneous disappearance and reappearance of a ruptured cerebral aneurysm is generally assumed to be a rare phenomenon although the actual incidence is unknown. Among 39 consecutive cases of acute subarachnoid hemorrhage (SAH), 33 were studied by three-dimensional computed tomographic angiography (CTA) within 6 h after the onset of SAH, followed by digital subtraction angiography (DSA) within 24 h after the ictus. Of those patients, one, a 58-year-old woman, had a saccular aneurysm at the distal anterior cerebral artery; the aneurysm was clearly demonstrated by CTA 2.5 h after the SAH onset, but was not shown by a subsequent DSA performed 8.5 h after the ictus. A follow-up DSA detected the neck of aneurysm on day 11, and the whole aneurysm was visualized on day 19. The observations in this particular case suggest that the spontaneous disappearance of a ruptured cerebral aneurysm may occur during the ultra-early stage of SAH and that reappearance may follow during the next few weeks. The patient did not suffer complications such as vasospasm or systemic hypotension nor was she treated with antifibrinolytic agents. The aneurysmal shape and the surrounding clot are considered as putative factors possibly related to the intermittent appearance of the aneurysm.

Endothelin-1 improves the impaired filterability of red blood cells through the activation of protein kinase C.

We previously showed that the deformability of human red blood cells (RBCs) is affected by intracellular signaling pathways by examining the effects of Ca2+ influx and the intracellular cAMP level on mechanically-impaired RBC filterability. In the present study, we investigated whether protein kinase C (PKC) participates in the regulation of RBC deformability by affecting membrane properties. The filterability of mechanically-stressed RBCs showed a V-shaped curve depending on the extracellular Ca2+ concentration; the maximum decrease was achieved at 20-40 microM. The PKC activity, as measured in the membrane-rich fraction by an ELISA method using an antibody for the phosphorylated PKC substrate, maximally increased at the extracellular Ca2+ concentration where the filterability showed a marked improvement following the bottom of the V-shaped curve of the impaired filterability. At this Ca2+ concentration, the PKC activator endothelin-1 increased the PKC activity, and a PKC inhibitor (calphostin C) decreased it. Endothelin-1 improved and calphostin C worsened the impaired filterability. A specific type-B endothelin receptor agonist (IRL 1620) also improved the impaired filterability. A Western blot analysis revealed the presence of endothelin receptors in the RBC membrane. These results indicate that PKC improves the impaired filterability and that RBCs are the target of endothelin-1.

Quantitative characterization of P-glycoprotein-mediated transport in mdr1-gene-transfected lymphoma cells.

We have established a quantitative flow cytometry system to elucidate the causal role of P-glycoprotein in the phenomenon of multidrug resistance. We have used this method to analyze the accumulation and release of adriamycin (ADM) in intact L5178Y and L5178Y/VMDR/C.06 (L5178Y/R) cells, by determining the effect of sodium orthovanadate (Na3VO4), verapamil, bovine serum albumin (BSA) and physiologically operative materials on the cells. Based on the experiments, we prepared a standard solution that contained NaCl, D-glucose, L-cysteine, HCO3- and BSA, which was sufficient to perform transport experiments. In particular, BSA caused a decrease in ADM accumulation and a facilitation of the rate of ADM release in both L5178Y and L5178Y/R cells, probably due to its relatively high affinity for ADM as compared to the cell membrane. In multidrug-resistant L5178Y/R cells, sodium orthovanadate, a strong ATP-binding inhibitor, caused a marked increase in the accumulation of ADM, whereas vanadate-treated drug-sensitive L5178Y cells showed little increase in ADM accumulation. In a release (0-trans exit) experiment, vanadate-treated L5178Y/R cells exhibited an apparent decrease in ADM release (increase in ADM retention), to a level which was almost the same as L5178Y cells. We thus confirmed that the P-glycoprotein-mediated efflux system is coupled with P-glycoprotein-associated ATP-hydrolysis. Further, verapamil, a potent inhibitor of P-glycoprotein-mediated transport, facilitated the ADM accumulation in L5178Y/R cells up to the level of L5178Y and vanadate-treated L5178Y/R cells. A more important finding is that, in the release experiment, verapamil-treated L5178Y/R cells exhibited a much greater ADM retention than drug-sensitive L5178Y and vanadate-treated L5178Y/R cells. These findings, in particular the potent effect of verapamil on drug-resistant cells, may afford new insight into the pathophysiology of the phenomenon of multidrug resistance and the mechanism of action of the multidrug transporter.

[Lymphocytic infundibuloneurohypophysitis during the first remission in acute lymphoblastic leukemia].

A 15-year-old girl developed acute lymphoblastic leukemia (ALL). The patient was treated according to the 13th protocol of the Tokyo Children's Cancer Study Group, and thereafter remained free of disease. However, at the age of 20, she complained of polyuria, polydipsia and amenorrhea. Hematological or meningeal relapse was ruled out on the basis of clinical and laboratory findings. The plasma concentrations of GH, TSH, LH, FSH, ACTH and ADH were low or below the detectable limits. There was no increase in urine osmolarity after water deprivation. Arginine, LH-RH, TRH and CRH tolerance tests revealed no or low responses of GH, LH/FSH, TSH, and ACTH/cortisol, respectively. Magnetic resonance imaging demonstrated thickening of the pituitary stalk, which was homogeneously enhanced by gadolinium administration. A biopsy specimen showed fibrosis and infiltration of CD8-positive T lymphocytes in a portion of the pituitary stalk, whereas the adenohypophysis was normal. In addition, no leukemic cells were observed in the samples. Thus, a diagnosis of lymphocytic infundibuloneurohyophysitis (LIN) was established. All the symptoms were improved by treatment with hydrocortisone, L-thyroxine, desamino-8-d-arginine vasopressin, estrogen and gestagen. This is the first reported case of ALL complicated by LIN.

[The value of intracellular CD41 antigen detection to the diagnosis of acute megakaryoblastic leukemia].

An 11-month-old boy was transferred to our hospital because of fever and bleeding tendency on March 13, 1998. Laboratory studies showed a white blood cell count of 43,360/microliter with 75% blasts, a hemoglobin concentration of 8.4 g/dl, and a platelet count of 23 x 10(3)/microliter. Surface marker analysis with a flow cytometer revealed that only 21% and 11% of the blasts, respectively, were positive for CD41 and CD42b. Treatment with a permeabilizing agent apparently increased the reactivity of the blasts with anti-CD41 monoclonal antibody (MoAb), which can recognize IIb independently of IIIa. However no significant differences were observed in reactivity with anti-CD41 MoAb (which recognizes the IIb/IIIa complex) anti-CD61 MoAb and anti-CD42b MoAb before or after fixation. Blasts positive for platelet peroxidase were observed by electron microscopy, thus confirming the diagnosis of acute megakaryoblastic leukemia. We concluded that the detection of intracellular antigens is useful for the quick diagnosis of acute megakaryoblastic leukemia characterized by low surface expression of megakaryocytic lineage antigens.

[An analysis of sclerodermatous graft-versus-host-disease after allogeneic bone marrow transplantation: CD8+CD57+T-cell proliferation and increased production of TGF-beta].

A 19-year-old woman with acute lymphoblastic leukemia received an allogeneic bone marrow transplantation (BMT) from an HLA-identical sibling during the second remission, on September 28, 1993. The conditioning regimen consisted of total body irradiation and cyclophosphamide. Short term methotrexate and cyclosporin A were given for prophylaxis of graft-versus-host disease (GVHD). On day 771 after BMT, she complained of bilateral forearm pain, and developed sclerotic lesions on the skin of the abdominal wall, forearms and legs. The diagnosis of sclerodermatous GVHD was established by skin biopsy on day 834. The values of CRP and IgG were elevated, and both antinuclear antibody and anti-DNA antibody became positive. Flow cytometric analysis showed a significant increase in the number of CD57+ cells after appearance of sclerotic change. In addition, 65% of CD8+ cells were positive for CD57. Circulating level of transforming growth factor (TGF)-beta 1 was high. These results suggest that overproduction of CD8+ CD57+ T cells and high level of circulating TGF-beta are related to the development of sclerodermatous GVHD.

[Prognostic significance of chromosome analysis in childhood acute lymphoblastic leukemia. Children's Cancer and Leukemia Study Group (CCLSG)].

We analyzed the prognostic significance of chromosomal findings in children with acute lymphoblastic leukemia (ALL), treated according to the Children's Cancer and Leukemia Study Group protocols between 1987 and 1993. Patients were classified into 5 groups according to chromosome number. The patients with a hyperdiploid(> 50) karyotype(13%) had the best prognosis [4-year event-free survival (EFS): 83 +/- 6%], while those with a pseudodiploid karyotype (24%) had the worst prognosis(4-year EFS: 52 +/- 6%) (log-rank, p = 0.03). However, multivariate analysis revealed that the ploidy classification had no prognostic significance in terms of EFS. When patients were classified according to chromosome abnormalities, those with any type of translocation had a worse outcome (4-year EFS: 33 +/- 9%) than those with hyperdiploidy(> 50), normal diploidy, and other abnormalities(log-rank, p < 0.0001). Multivariate analysis revealed that chromosome abnormalities were an independent prognostic factor (relative risk 3.98; p < 0.0001). Patients with t(1; 19) had an EFS similar to that of patients with chromosome abnormalities other than translocations or normal diploidy. We conclude that chromosomal findings have prognostic significance, although some chromosome abnormalities lost their statistical significance after modern intensified chemotherapy. Childhood ALL should be further stratified according to chromosome classification.

Engraftment syndrome, but not acute GVHD, younger age, CYP3A5 or MDR1 polymorphisms, increases tacrolimus clearance in pediatric hematopoietic SCT.

We investigated clinical factors that affected the clearance of tacrolimus (FK506) administered by continuous drip infusion to children who had received allogeneic hematopoietic SCT. Blood FK506 levels were measured every day in 27 patients in an attempt to adjust the dose to maintain the target range (10-15 ng/mL). Patients who developed engraftment syndrome (ES) and acute GVHD and patients less than 7 years of age showed a higher FK506 clearance calculated from body weight (BW) for 5 or more consecutive days compared with the control groups. A time-course study showed that the occurrence of ES, but not acute GVHD, was related to increased clearance of FK506. When calculated from body surface area (BSA), a significant increase in FK506 clearance was observed in patients with ES, but not in those less than 7 years of age. FK506 clearance was not influenced by CYP3A5, multidrug resistance 1 or ABCG2 genotypes. None of the clinical parameters affected blood FK506 levels. Determination of the FK506 dose on the basis of frequent monitoring of the blood concentration seems to minimize the serious adverse effects induced by the immunosuppressant. It may be more accurate to dose FK506 according to BSA rather than BW for pediatric patients.