Effects on Pediatric Cancer Survivors: The FAMily-Oriented Support (FAMOS) Randomized Controlled Trial.

OBJECTIVE: To examine as secondary analyses the effect the FAMily-Oriented Support (FAMOS) family therapy program on reducing parent-reported medical traumatic stress in the sub-sample of pediatric cancer survivors, age 2-5 years. METHODS: The FAMOS study was a national multicenter randomized controlled trial with all four pediatric oncology departments in Denmark (Clinicaltrials.gov [NCT02200731]). Families were randomized in parallel design (1:1) to intervention or usual care. The FAMOS program includes seven home-based psychotherapeutic sessions and is based on family systems therapy to address the individuals in the family system using cognitive behavioral, problem-solving and goal-setting techniques. Questionnaires were completed by parents at baseline, 6, and 12 months. In linear mixed-effects models, the effect of FAMOS on reducing children's trauma-related behavior after 6 and 12 months was examined in 62 children (31 in the intervention and 29 in the control group, respectively). It was also examined if a trauma-related behavior effect was mediated through reduced symptoms of depression in mothers and fathers, respectively. RESULTS: On average, children in the intervention group experienced significantly larger decreases in trauma-related behaviors at 6 and 12 months than the control group (predicted mean difference -3.89, p = .02 and -6.24, p = .003, respectively). The effect on trauma-related behavior was partly mediated through reduced symptoms of depression in mothers, but not fathers. CONCLUSIONS: Adding to previously reported positive effects of the FAMOS intervention on parents' symptoms of post-traumatic stress and depression, significant improvements were found in young children's trauma related-behavior. Further research is needed to develop therapy for children with cancer.

Home-based cognitive behavioural therapy for families of young children with cancer (FAMOS): A nationwide randomised controlled trial.

INTRODUCTION: Evidence-based knowledge is needed to reduce psychological symptoms in families of young children with cancer after treatment ends. OBJECTIVE: To evaluate the effect of a psychotherapeutic intervention, FAMily-Oriented Support (FAMOS) on parents of young children after cancer treatment. METHODS: All families of children aged 0-6 years who had been treated for cancer at one of the four paediatric oncology departments in Denmark were invited to participate after ending intensive medical treatment. The families were randomly assigned 1:1 to up to seven sessions of FAMOS, a cognitive-behavioural manualised home intervention, for 6 months or to usual psychosocial care. The primary outcome was parents' symptoms of posttraumatic stress disorder (PTSD) at 6 and 12 months after enrolment. The secondary outcomes were parents' symptoms of depression and anxiety. RESULTS: We enrolled 109 families (204 parents). Parents in the intervention group did not show a statistically significant decrease in symptoms of PTSD as compared with the control group at 6 months (predicted mean difference, -0.10; 95% confidence interval [CI] -0.19, 0.01), but a statistically significant decrease was seen at 12 months (predicted mean difference, -0.15; 95% CI -0.28, -0.02), and they had significantly lower symptoms of depression at both 6 and 12 months. Differences in reductions in symptoms of anxiety were not statistically significant. CONCLUSIONS: The FAMOS intervention reduced parents' symptoms of PTSD and depression. Next step is to also report on psychological effects in the children and siblings (clinicaltrials.gov: NCT02200731).

Meropenem to Children With Febrile Neutropenia Induces Monoresistant Pseudomonas aeruginosa.

Antimicrobial resistance in Pseudomonas aeruginosa is a threat to children with cancer. We explored the association between P. aeruginosa resistance and previous antibiotic exposure. All children with cancer and P. aeruginosa bacteremia in 2007 to 2016 in Denmark, a country with an overall resistance rate of ∼3%, were included. Twenty percent (10/49) of isolates from children previously exposed to meropenem were meropenem nonsusceptible. The only significant risk factor of meropenem nonsusceptibility was previous meropenem therapy (P=0.03). On the basis of these results, we suggest that meropenem should be reserved as a last resort for children with febrile neutropenia in countries with low antimicrobial resistance.

Plasma creatinine as predictor of delayed elimination of high-dose methotrexate in childhood acute lymphoblastic leukemia: A Danish population-based study.

BACKGROUND: Severely delayed elimination of methotrexate (MTX) is difficult to predict in patients treated with high-dose MTX (HD-MTX), but it may cause life-threatening toxicity. It has not been defined how an increase in plasma creatinine can be best used as a predictor for severely delayed MTX elimination, thus providing a guide for therapeutic interventions to minimize renal toxicity. METHODS: Pharmacokinetic data were retrospectively collected on 218 Danish children with acute lymphoblastic leukemia treated with HD-MTX 5 or 8 g/m2 on the NOPHO2000 protocol. Moderately delayed MTX elimination was defined as 42-hour plasma MTX ≥ 4.0-9.9 µM, and severely delayed elimination was defined as 42-hour plasma MTX ≥ 10 µM. RESULTS: Median 42-hour plasma MTX was 0.61 µM (interquartile range, 0.4-1.06 µM). Of 1295 MTX infusions with 5 g/m2 (n = 140 patients) or 8 g/m2 (n = 78 patients), 5.1% were severely (1.5%) or moderately (3.6%) delayed. The risk of having delayed elimination was highest in the first of eight infusions with MTX 5 g/m² (7.4% vs 0.0 to 4.1% for subsequent MTX infusions) (P < 0.02). A 25 µM increase or a 1.5-fold increase in plasma creatinine within 36 hours from start of the MTX infusion had a sensitivity of 92% (95% CI, 82%-97%) and a specificity of 85% (95% CI, 83%-87%) for predicting 42-hour MTX ≥4.0 µM. CONCLUSIONS: A 25 µM increase or a 1.5-fold in plasma creatinine within 36 hours after start of an HD-MTX infusion can predict delayed MTX elimination, thus allowing intensification of hydration and alkalization to avoid further renal toxicity and promote the elimination of MTX.

Hepatic sinusoidal obstruction syndrome during maintenance therapy of childhood acute lymphoblastic leukemia is associated with continuous asparaginase therapy and mercaptopurine metabolites.

BACKGROUND: Hepatic sinusoidal obstruction syndrome (SOS) during treatment of childhood acute lymphoblastic leukemia (ALL) has mainly been associated with 6-thioguanine. The occurrence of several SOS cases after the introduction of extended pegylated asparaginase (PEG-asparaginase) therapy in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol led us to hypothesize that PEG-asparaginase, combined with other drugs, may trigger SOS during 6-thioguanine-free maintenance therapy. PROCEDURE: In children with ALL treated in Denmark according to the NOPHO ALL2008 protocol, we investigated the risk of SOS during methotrexate (MTX)/6-mercaptopurine (6MP) maintenance therapy that included PEG-asparaginase until week 33 (randomized to two- vs. six-week intervals), as well as alternating high-dose MTX or vincristine/dexamethasone pulses every four weeks. RESULTS: Among 130 children receiving PEG-asparaginase biweekly, 29 developed SOS (≥2 criteria: hyperbilirubinemia, hepatomegaly, ascites, weight gain ≥2.5%, unexplained thrombocytopenia <75 × 109 l-1 ) at a median of 30 days (interquartile range [IQR]: 17-66) into maintenance (cumulative incidence: 27%). SOS cases fulfilling one, two, or three Ponte di Legno criteria were classified as possible (n = 2), probable (n = 8), or verified (n = 19) SOS, respectively. Twenty-six cases (90%) occurred during PEG-asparaginase treatment, including 21 (81%) within 14 days from the last chemotherapy pulse compared with the subsequent 14 days (P = 0.0025). Cytotoxic 6MP metabolites were significantly higher on PEG-asparaginase compared to after its discontinuation. Time-dependent Cox regression analysis showed increased SOS hazard ratio (HR) for erythrocyte levels of methylated 6MP metabolites (HR: 1.09 per 1,000 nmol/mmol hemoglobin increase, 95% confidence interval: 1.05-1.14). Six-week PEG-asparaginase intervals significantly reduced SOS-specific hazards (P < 0.01). CONCLUSIONS: PEG-asparaginase increases cytotoxic 6MP metabolite levels and risk of SOS, potentially interacting with other chemotherapy pulses.

FAMily-Oriented Support (FAMOS): development and feasibility of a psychosocial intervention for families of childhood cancer survivors.

BACKGROUND: We developed and tested the feasibility of a manualized psychosocial intervention, FAMily-Oriented Support (FAMOS), a home-based psychosocial intervention for families of childhood cancer survivors. The aim of the intervention is to support families in adopting healthy strategies to cope with the psychological consequences of childhood cancer. The intervention is now being evaluated in a nationwide randomized controlled trial (RCT). METHODS AND DESIGN: FAMOS is based on principles of family systems therapy and cognitive behavioral therapy, and is delivered in six sessions at home. Families were recruited from all four pediatric oncology departments in Denmark after the end of intensive cancer treatment. We evaluated the feasibility of the intervention and of a RCT design for comparing the intervention with usual care. The evaluation was conducted among families enrolled in the study by tracking procedures and parents' evaluations. RESULTS: A total of 68 families (68 mothers, 60 fathers, 68 children with cancer and 73 siblings) were enrolled, with a participation rate of 62% of families. Fathers were highly represented (88% of families); also families with single parents (12%) and parents with basic education (7-12 years of primary, secondary, and grammar school education) were represented (12%). The dropout rate was 12% of families (all in the control group), and two families did not complete the intervention because of relapse. Evaluation by parents in the intervention group showed overall satisfaction with the format, timing, and content of the intervention. CONCLUSION: The results indicate that the FAMOS intervention is feasible in terms of recruitment, retention, and acceptability. The effects of the intervention on post-traumatic stress, depression, anxiety, family functioning, and quality of life will be reported after the nationwide RCT has been completed.

Flow cytometric measurement of platelet-associated immunoglobulin in children with newly diagnosed Immune Thrombocytopenia.

OBJECTIVE: To explore the clinical utility of measuring platelet-associated immunoglobulin (PAIG) at the time of diagnosis in children with immune thrombocytopenia (ITP). METHODS: PAIG was measured by flow cytometry using fluorescent murine anti-IgG and anti-IgM. In a cohort of 88 children with ITP, the assay was performed within 15 days of diagnosis and before any treatment in 68 cases. We reviewed the results and examined the relation of isotype profile and degree of elevation to clinical manifestations and course of disease. RESULTS: PAIG was elevated in 74%, with raised IgM being more frequent than IgG (63% vs. 44%, P = 0.04) and with isotype profile depending on symptom onset. Platelet counts at presentation were similar in all subgroups, but mucosal bleeding was less frequent in PAIG-negative patients compared to the positive groups (5.5% vs. 34%, P = 0.03). Duration of thrombocytopenia was similar in negative and positive cases, but during follow-up, significant bleeding events occurred less frequently in PAIG-negative patients (0% vs. 14%, P = 0.18). CONCLUSION: Approximately one-quarter of children are PAIG-negative, and these children have milder bleeding tendency at diagnosis and lower morbidity during follow-up. Raised PAIG possibly may cause some degree of platelet dysfunction.

Central Venous Catheters and Bloodstream Infection During Induction Therapy in Children With Acute Lymphoblastic Leukemia.

The purpose of the study was to assess the risk of first-time bloodstream infection (BSI) according to type of central venous catheter (CVC) during induction therapy in children with acute lymphoblastic leukemia (ALL). Patients eligible for our analysis were all newly diagnosed children with ALL treated at 3 pediatric centers in Denmark between 2008 and 2014. A total of 136 patients were followed from initial CVC placement until first BSI, CVC removal, death, or day 28, whichever occurred first. Thirty-nine BSIs were detected, of which 67% were gram-positive infections, and 59% met the criteria for being CVC associated. The 28-day cumulative incidence of BSI was similar in 77 patients with a nontunneled CVC (28%; 95% confidence interval, 19%-40%) and in 59 patients with a tunneled CVC with external lines (TE) (33%; 95% confidence interval, 23%-47%). Subgroup analyses showed that gram-negative blood isolates occurred more frequently in patients with a TE, and that lower incidences of BSI were detected in patients older than 9 years with a TE, and in patients with T-ALL. It is concluded that the type of CVC inserted at diagnosis has no impact upon the risk of BSI in patients with ALL undergoing induction therapy.

Cerebrospinal fluid asparagine depletion during pegylated asparaginase therapy in children with acute lymphoblastic leukaemia.

L-asparaginase is an important drug in the treatment of childhood acute lymphoblastic leukaemia (ALL). Cerebrospinal fluid (CSF) asparagine depletion is considered a marker of asparaginase effect in the central nervous system (CNS) and may play a role in CNS-directed anti-leukaemia therapy. The objective of this study was to describe CSF asparagine depletion during 30 weeks of pegylated asparaginase therapy, 1000 iu/m(2) i.m. every second week, and to correlate CSF asparagine concentration with serum L-asparaginase enzyme activity. Danish children (1-17 years) with ALL, treated according to the Nordic Society of Paediatric Haematology and Oncology ALL2008 protocol, standard and intermediate risk, were included. CSF samples were obtained throughout L-asparaginase treatment at every scheduled lumbar puncture. A total of 128 samples from 31 patients were available for analysis. Median CSF asparagine concentration decreased from a pre-treatment level of 5·3 µmol/l to median levels ≤1·5 µmol/l. However, only 4/31 patients (five samples) had CSF asparagine concentrations below the limit of detection (0·1 µmol/l). In 11 patients, 24 paired same day serum and CSF samples were obtained. A decrease in CSF asparagine corresponded to serum enzyme activities above 50 iu/l. Higher serum enzyme activities were not followed by more extensive depletion. In conclusion, pegylated asparaginase 1000 iu/m(2) i.m. every second week effectively reduced CSF asparagine levels.

Very late relapse of PTLD 10 yr after allogeneic HSCT and nine yr after stopping immunosuppressive therapy.

We present a very late onset relapse of PTLD 10 yr after allogeneic HSCT in a patient in third remission for ALL, nine yr after the first episode of PTLD. The recipient was conditioned with fractionated TBI 12 Gy, cyclophosphamide, and horse ATG. The first episode of PTLD with a large retroperitoneal tumor occurred one yr after transplantation; a residual tumor infiltrating spleen and colon was resected one yr later. Due to continual pathological signals in liver and lungs, persistent fever, and an M-component in peripheral blood, a new course of four rituximab doses was given, after which the fever settled, the PET scan normalized, and the M-component disappeared. Without any ongoing immunosuppressive therapy, PTLD relapsed nine yr later with large intra-abdominal lymph node masses causing ureteric obstruction with bilateral hydronephrosis. Pathological features were identical to the primary PTLD tumor: EBV related, of donor origin, positive for CD138 and CD79 alpha, but negative for CD20 and CD19. The transcription factor PAX5 was negative but BOB1 and OCT2 were positive, consistent with plasmablastic lymphoma. The relapse was successfully treated with a combination of low dose chemotherapy and rituximab. Five yr after end of treatment, the girl has moderately reduced renal function but otherwise remains well without evidence of disease.

Familial hemophagocytic lymphohistiocytosis type 3 (FHL3) caused by deep intronic mutation and inversion in UNC13D.

Familial hemophagocytic lymphohistiocytosis (FHL) is an autosomal recessive, often-fatal hyperinflammatory disorder. Mutations in PRF1, UNC13D, STX11, and STXBP2 are causative of FHL2, 3, 4, and 5, respectively. In a majority of suspected FHL patients from Northern Europe, sequencing of exons and splice sites of such genes required for lymphocyte cytotoxicity revealed no or only monoallelic UNC13D mutations. Here, in 21 patients, we describe 2 pathogenic, noncoding aberrations of UNC13D. The first is a point mutation localized in an evolutionarily conserved region of intron 1. This mutation selectively impairs UNC13D transcription in lymphocytes, abolishing Munc13-4 expression. The second is a 253-kb inversion straddling UNC13D, affecting the 3'-end of the transcript and likewise abolishing Munc13-4 expression. Carriership of the intron 1 mutation was found in patients across Europe, whereas carriership of the inversion was limited to Northern Europe. Notably, the latter aberration represents the first description of an autosomal recessive human disease caused by an inversion. These findings implicate an intronic sequence in cell-type specific expression of Munc13-4 and signify variations outside exons and splice sites as a common cause of FHL3. Based on these data, we propose a strategy for targeted sequencing of evolutionary conserved noncoding regions for the diagnosis of primary immunodeficiencies.

Impact of hydrochloric acid instillation on salvage of infected central venous catheters in children with acute lymphoblastic leukaemia.

BACKGROUND: Bacteraemia associated with indwelling central venous catheters (CVC) causes significant morbidity in children with cancer. Hydrochloric acid (HCl) instillations have been reported to salvage CVCs with antibiotic-refractory infection. We implemented this treatment in 2002. The impact on the survival of CVCs has been evaluated in a retrospective cohort study of children with acute lymphoblastic leukaemia (ALL). METHODS: Children with newly diagnosed ALL during 1999-2005 having their first CVC inserted before (n = 16) and after (n = 24) the introduction of the procedure were studied. All bacteraemic episodes were reviewed, recording bacteriological findings and treatment, and the time to premature or planned removal of the CVC was determined. RESULTS: In the comparison cohort, 31.0% (9/29) of bacteraemic episodes led to removal of the CVC, compared to 5.5% (2/36) in the intervention cohort (p = 0.01). Thus, the rate of catheter loss due to infection fell from 56.3% (9/16) to 8.3% (2/24) after introducing HCl treatment (p = 0.0025). Overall, the premature catheter removal rate fell from 75.0% (12/16) to 45.8% (11/24) (p = 0.10). Analysed in a CUSUM plot the reduced frequency of premature CVC removal evidently coincided with the introduction of the procedure. In a subgroup analysis of 21 monobacterial infections with coagulase-negative staphylococci, a decrease in systemic and lock antibiotic therapy was found. No adverse events were noted. CONCLUSIONS: HCl instillations significantly reduced the need to remove and replace CVCs. The procedure is practical, appears to be safe, and may reduce the consumption of antibiotics.

Prediction of bacteremia in children with febrile episodes during chemotherapy for acute lymphoblastic leukemia.

The purpose was to identify risk factors for bacteremia in febrile episodes occurring during chemotherapy for acute lymphoblastic leukemia (ALL) in children, and to develop a risk score permitting risk-adapted antibiotic therapy. We reviewed a total of 172 febrile episodes occurring during chemotherapy in 31 children and adolescents with ALL. Temperature, hematological parameters, culture findings, and antibiotic therapy were recorded. Bacteremias were classified as transmucosal or CVC-dependent. Blood cultures were positive with mucosal pathogens in 15 cases (9%) and with skin/environmental bacteria in 34 (20%). CVC-dependent infections occurred throughout the treatment phases, while transmucosal primarily during induction therapy. Transmucosal bacteremia was associated with induction therapy, leukocyte count ≤0.5 × 10(9)/L, neutrophil count ≤0.1 × 10(9)/L, monocyte count ≤0.01 × 10(9)/L, and platelet count ≤50 × 10(9)/L. Based on logistic conversion of the odds ratios for the five factors, a weight of 2 was assigned to induction therapy and leukocyte count ≤0.5 × 10(9)/L, and a weight of 1 to the remaining three parameters. The weights were included in a simple additive score ranging from 0 to 7, which defined groups with 4%, 6%, 24%, and 40% risk of transmucosal bacteremia. CVC-dependent bacteremia was not associated with markers of poor bone marrow function. In conclusion, transmucosal bacteremia in children with ALL is related to infiltration or suppression of the bone marrow. A score reflecting the condition of the marrow can define low-risk and high-risk groups and may prove clinically useful.

Epidemiological Study of Malignant Paediatric Liver Tumours in Denmark 1985-2020.

BACKGROUND: Malignant liver tumours in children are rare and national outcomes for this tumour entity are rarely published. This study mapped paediatric liver tumours in Denmark over 35 years and reported on the incidence, outcomes and long-term adverse events. METHODS: We identified all liver tumours from the Danish Childhood Cancer Registry and reviewed the case records for patient and tumour characteristics, treatment and clinical outcome. RESULTS: We included 79 patients in the analyses. Overall crude incidence was ~2.29 per 1 million children (<15 yr) per year, with 61 hepatoblastomas (HB), 9 hepatocellular carcinomas and 9 other hepatic tumours. Overall 5-year survival was 84%, 78% and 44%, respectively. Nine patients had underlying liver disease or predisposition syndrome. Seventeen children underwent liver transplantation, with two late complications, biliary stenosis and liver fibrosis. For HB, age ≥ 8 years and diagnosis prior to 2000 were significant predictors of a poorer outcome. Adverse events included reduced renal function in 10%, reduced cardiac function in 6% and impaired hearing function in 60% (19% needed hearing aids). Behavioural conditions requiring additional support in school were registered in 10 children. CONCLUSIONS: In Denmark, incidences of malignant liver tumours during the last four decades have been increasing, as reported in the literature. HB survival has improved since the year 2000 and is comparable with international results. Reduced hearing is the major treatment-related side effect and affects approximately 60% of patients.

Duration and morbidity of chronic immune thrombocytopenic purpura in children: five-year follow-up of a Nordic cohort.

AIM: To describe the clinical course, morbidity and platelet recovery in an unselected Nordic cohort of children with chronic Immune Thrombocytopenic Purpura (ITP). METHODS: Prospective 5-year follow-up of 96 children with ITP lasting more than 6 months, with reporting of hospital admissions, severity of bleeding episodes and stabilization of platelet counts above 20, 50 and 150 × 10(9) /L. RESULTS: The estimated 5-year recovery rate was 52%; exclusion of 12 splenectomized children did not change the estimate. Events eliciting admission to hospital occurred in 39 (41%). Major haemorrhages occurred in eight children (8%), including a nonfatal intracranial haemorrhage in one child (1%). The overall admission rate was 0.4/year of thrombocytopenia, decreasing during follow-up as thrombocytopenia converted to milder degrees. Early recovery within 2 years of diagnosis occurred in 35%, was associated with low morbidity and was more likely in young children with abrupt onset of symptoms. CONCLUSION: In a Nordic cohort of children with chronic ITP, one half had recovered 5 years after diagnosis, more than half never required hospitalization and <10% experienced serious bleeding episodes, always with a platelet count <20 × 10(9) /L. Aggressive management can be restricted to the minority of children with continuing severe thrombocytopenia and frequent, clinically significant bleeding events.

High CD34 surface expression in BCP-ALL predicts poor induction therapy response and is associated with altered expression of genes related to cell migration and adhesion.

Minimal residual disease (MRD) constitutes the most important prognostic factor in B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Flow cytometry is widely used in MRD assessment, yet little is known regarding the effect of different immunophenotypic subsets on outcome. In this study of 200 BCP-ALL patients, we found that a CD34-positive, CD38 dim-positive, nTdT dim-positive immunophenotype on the leukemic blasts was associated with poor induction therapy response and predicted an MRD level at the end of induction therapy (EOI) of ≥ 0.001. CD34 expression was strongly and positively associated with EOI MRD, whereas CD34-negative patients had a low relapse risk. Further, CD34 expression increased from diagnosis to relapse. CD34 is a stemness-associated cell-surface molecule, possibly involved in cell adhesion/migration or survival. Accordingly, genes associated with stemness were overrepresented among the most upregulated genes in CD34-positive leukemias, and protein-protein interaction networks showed an overrepresentation of genes associated with cell migration, cell adhesion, and negative regulation of apoptosis. The present work is the first to demonstrate a CD34-negative immunophenotype as a good prognostic factor in ALL, whereas high CD34 expression is associated with poor therapy response and an altered gene expression profile reminiscent of migrating cancer stem-like cells.

Different NK cell-activating receptors preferentially recruit Rab27a or Munc13-4 to perforin-containing granules for cytotoxicity.

The autosomal recessive immunodeficiencies Griscelli syndrome type 2 (GS2) and familial hemophagocytic lymphohistiocytosis type 3 (FHL3) are associated with loss-of-function mutations in RAB27A (encoding Rab27a) and UNC13D (encoding Munc13-4). Munc13-4 deficiency abrogates NK-cell release of perforin-containing lytic granules induced by signals for natural and antibody-dependent cellular cytotoxicity. We demonstrate here that these signals fail to induce degranulation in resting NK cells from Rab27a-deficient patients. In resting NK cells from healthy subjects, endogenous Rab27a and Munc13-4 do not colocalize extensively with perforin. However, phorbol 12-myristate 13-acetate and ionomycin stimulation or conjugation to susceptible target cells induced myosin-dependent colocalization of Rab27a and Munc13-4 with perforin. Unexpectedly, individual engagement of receptors leukocyte functional antigen-1, NKG2D, or 2B4 induced colocalization of Rab27a, but not Munc13-4, with perforin. Conversely, engagement of antibody-dependent cellular cytotoxicity receptor CD16 induced colocalization of Munc13-4, but not Rab27a, with perforin. Furthermore, colocalization of Munc13-4 with perforin was Rab27a-dependent. In conclusion, Rab27a or Munc13-4 recruitment to lytic granules is preferentially regulated by different receptor signals, demonstrating that individual target cell ligands regulate discrete molecular events for lytic granule maturation. The data suggest Rab27a facilitates degranulation at an early step yet highlight a reciprocal relationship between Munc13-4 and Rab27a for degranulation.

Bone marrow aspiration technique may have an impact on therapy stratification in children with acute lymphoblastic leukaemia.

BACKGROUND: Morphological evaluation of early response to chemotherapy and measurement of minimal residual disease by flow cytometry or PCR are being used for evaluation of prognosis and treatment stratification in children with acute lymphoblastic leukaemia (ALL). PROCEDURE: In a series of 14 consecutive bone marrow investigations from children with precursor B-cell ALL, morphological evaluations of smears and flow cytometric measurements of minimal residual disease in sequentially aspirated small (2 ml) and large (5-10 ml) volumes of bone marrow were compared, at various time points during therapy. RESULTS: The density of nucleated cells was markedly reduced in the large volume aspirate. The percentage of erythroblasts measured by flow cytometry was smaller, indicating dilution with peripheral cells. Similarly, the blast percentage was reduced with 54% in large aspirates, and in four instances with minimal residual disease of >0.1% in the small volume, the level of blasts in the large aspirate was below this limit. CONCLUSIONS: The amount of minimal residual disease should be measured in the first 2.5 ml of bone marrow aspirated from one puncture site. The procedure should be performed by experienced and carefully instructed doctors. In large aspirates, minimal residual disease will be underestimated, which may lead to failure to undertake a required intensification of therapy and a lower fraction of high risk patients in the trial.

The epidemiology of herpes zoster in 226 children with acute lymphoblastic leukemia.

BACKGROUND: Herpes zoster (HZ) is rare in healthy children, but may occur frequently and take a complicated course in children receiving chemotherapy. We determined the morbidity related to HZ in children with acute lymphoblastic leukaemia (ALL). PROCEDURE: Medical records of 226 children diagnosed with ALL were reviewed. Of these, 160 were seropositive at the time of diagnosis. HZ eruptions during primary chemotherapy, during therapy for relapse and following bone marrow transplantation (BMT) were registered. RESULTS: A total of 90 eruptions were recorded: 63 first-time attacks and 27 recurrent episodes among 14 children. All eruptions were treated with acyclovir (ACV) and in 60% it was given intravenously. Cutaneous dissemination occurred in 11 cases, post herpetic neuralgia in five, visceral dissemination in none. During primary chemotherapy 47 children (29%) had HZ. The eruption rate was significantly higher in children on high risk protocols compared to children on standard/intermediate risk protocols (0.36 vs. 0.07/0.09 per year) and was related to intensity of chemotherapy. During therapy for relapse 7 of 29 (24%) had a total of 13 eruptions. Following BMT 9 of 26 (35%) had a total of 10 eruptions. CONCLUSION: Almost one third of the seropositive children had HZ during primary chemotherapy. Of those treated on high risk protocols more than half had one or more eruptions during the course of treatment. The risk of complicated HZ is small, but prolonged intensive chemotherapy can lead to considerable morbidity from repeated eruptions. Attempts to improve immunity by vaccination after attaining remission seem warranted.

Successful implementation of a watchful waiting strategy for children with immune thrombocytopenia.

INTRODUCTION: Treatment of newly diagnosed immune thrombocytopenia (ITP) is controversial and guidelines vary internationally. At the Paediatric Department, Aalborg Hospital, a "watchful waiting" approach was adopted in the early 2000s. We aimed to investigate whether this change in strategy had any adverse effects on the subsequent clinical outcomes. MATERIAL AND METHODS: Medical records were reviewed for children with ITP presenting with a platelet count < 30 billion/l in the 1990s (n = 22) and in the 2000s (n = 47). Management during the initial admission and events during the first 12 months after diagnosis were recorded. RESULTS: The rate of initial treatment with immunoglobulin or steroids was reduced from 64% in the 1990s to 15% in the 2000s. The percentage of children with ITP lasting more than three months did not increase (30% versus 32%). Nor did the occurrence of ITP lasting > 12 months (15% versus 27%). The proportion of children requiring readmission (19% versus 27%) or receiving therapy during follow-up (19% versus 23%) was unchanged. Serious bleeding requiring immediate intervention was equally rare (one episode in the 1990s, two in the 2000s). Cusum plots usefully depicted the changes in management and confirmed that the rate of adverse events did not increase. CONCLUSION: A watchful waiting strategy for children with newly diagnosed ITP has been implemented without adverse effects on the duration or the morbidity of ITP.