Complications associated with central venous access device in children with haemophilia: a nationwide multicentre study in Finland.

Children with haemophilia require venous access for regular infusion of coagulation factors. A central venous access device (CVAD) ensures long-term access but associates with infectious and non-infectious complications with proposed risk factors of young age at initial CVAD implantation and presence of an inhibitor. Our aim was to evaluate the incidence and risk factors for complications associated with CVAD usage in a retrospective nationwide multicentre study in five Finnish Paediatric Haemophilia Treatment Centers. Our study investigated 106 CVADs in 58 patients with 137 971 CVAD days. The median access survival was 1159 CVAD days, and most often a malfunction led to CVAD removal after a long survival (median of 1640 CVAD days). We detected a very low bloodstream infection rate (0.12/1000 CVAD days). The presence of neutralizing inhibitor was a significant risk factor for infection. Heparin vs. saline flushing did not influence the CVAD outcome. We detected a lower infection rate than previously reported, although 90% of the patients were very young (<2 years) at first insertion (median age = 1.02 year). Port access was frequent after initial implantation: six patients (10%) used the port daily for immune tolerance induction therapy and 74% at least twice weekly for prophylaxis. Young age did not increase the risk of infections, as 59% of the CVAD-related infections were recorded in children over 6 years of age. Our national experience confirms the safety of prophylactic factor concentrate administration via ports even in very young children.

Hypercalciuria and kidney function in children with haemophilia.

Adults with haemophilia have a higher incidence of chronic kidney disease than general male population. We recently showed that children with haemophilia have higher urinary calcium excretion and lower whole body bone mineral density than controls in spite of prophylaxis with the deficient coagulation factor concentrate, serum vitamin D concentrations comparable to those of healthy children and physically active lifestyle. Persistent hypercalciuria may result in nephrocalcinosis and impact renal function. This study sought to assess persistence of urinary calcium excretion and kidney function in children with haemophilia. We investigated retrospectively urinary calcium excretion in 30 children with haemophilia (mean age 12.5 years) from consecutive urine samples over a 2-year period. Renal evaluation included blood and urine specimen, blood pressure, and renal ultrasound. High number of children with haemophilia had intermittent hypercalciuria. Hypercalciuria was not associated with age, severity of haemophilia or previous hypercalciuria. Kidney function and renal ultrasound were normal with the exception of suspected kidney stone in one patient with haemophilia and transient hypercalciuria. Vitamin D concentrations improved after the families had received information and recommendations concerning vitamin D substitution. Our findings indicate that haemophilia per se predisposes to hypercalciuria which may in turn affect bone mineral content and kidney function. Whether childhood-onset intermittent hypercalciuria contributes to hypertension and renal complications in adulthood remains to be elucidated in future studies.

MRI after removal of central venous access device reveals a high number of asymptomatic thromboses in children with haemophilia.

Central venous access devices (CVADs) are often required in children with haemophilia to secure venous access for prophylactic treatment or immune tolerance therapy. Complications of CVADs include infections, thrombosis and mechanical problems. This study sought to determine the outcome of the vessels by magnetic resonance imaging (MRI) in children with haemophilia and to assess risk factors for development of catheter-related deep venous thrombosis (DVT). After the removal of CVAD an MRI of the chest and neck was performed to 20 boys with haemophilia who each had 1-3 (total number 27) CVADs placed. MRI revealed DVT in five children (25%). As their CVADs were functional at the time of the removal, the DVTs were clinically silent. However, there had been suspicion of DVT leading to replacement of the CVAD in one case. All the children with DVT had their CVADs inserted initially below the age of 1 year. The clinical signs of mild post-thrombotic syndrome (PTS) were common: dilated chest wall veins were observed in 11 (55%) children and were associated with DVT in three cases. Arm circumference discrepancy was observed in one child with DVT. No correlation between the duration or number of CVADs and DVT was detected. None of the patients had subjective symptoms of PTS. Silent DVT is a common complication of CVAD. Catheter insertion at a young age seems to predispose to thrombosis. The long-term consequences of the DVTs remain unknown.

Peripheral quantitative computed tomography (pQCT) reveals alterations in the three-dimensional bone structure in children with haemophilia.

Children with haemophilia are at risk of suboptimal bone mass accrual and low bone mineral density (BMD). We recently demonstrated that although BMD in Finnish children with haemophilia was within the normal range, their whole body BMD was significantly lower and hypercalciuria more prevalent than in controls. This study sought to determine the bone structure and strength in physically active children with haemophilia. To investigate the underlying mechanisms in this group, we conducted a case-control study to assess bone structure and strength by peripheral quantitative computed tomography (pQCT) at the radius. The study group comprised 29 patients (mean age 12.2 years) and 46 age-matched controls. Children with haemophilia had decreased total BMD Z-score at the distal radius (P ≤ 0.001), but increased cortical bone density at the proximal radius (P ≤ 0.001). Total bone area at the proximal radius was significantly lower in children with haemophilia (P = 0.002), whereas there were no differences in cortical bone area or in polar Strength-Strain Index, a parameter of bone strength, between the patients and controls. Patients with mild to moderate haemophilia and on-demand treatment had inferior bone strength compared to those with moderate to severe haemophilia and prophylaxis. Our findings suggest altered skeletal development in patients with haemophilia in the radius, resulting in smaller bone size and higher cortical bone density. Importantly, bone strength at the radius appears equal to healthy children. Prophylactic treatment seems to have a beneficial effect on bone health.

Variation in baseline factor VIII concentration in a retrospective cohort of mild/moderate hemophilia A patients carrying identical F8 mutations.

Essentials Factor VIII levels vary in mild and moderate hemophilia A (MHA) patients with the same mutation. We aimed to estimate the variation and determinants of factor VIII levels among MHA patients. Age and genotype explain 59% of the observed inter-individual variation in factor VIII levels. Intra-individual variation accounted for 45% of the variation in the three largest mutation groups. SUMMARY: Background The bleeding phenotype in patients with mild/moderate hemophilia A (MHA) is inversely associated with the residual plasma concentration of factor VIII (FVIII:C). Within a group of patients with the same F8 missense mutation, baseline FVIII:C may vary, because, in healthy individuals, von Willebrand factor (VWF) levels, ABO blood group and age are also known to influence baseline FVIII:C. Our understanding of the pathophysiologic process of the causative genetic event leading to reduced baseline FVIII:C in MHA patients is still limited. Objectives To estimate the variation and determinants of baseline FVIII:C among MHA patients with the same F8 missense mutation. Methods Three hundred and forty-six patients carrying mutations that were present in at least 10 patients in the cohort were selected from the INSIGHT and the RISE studies, which are cohort studies including data of 3534 MHA patients from Europe, Canada, and Australia. Baseline FVIII:C was measured with a one-stage clotting assay. We used Levene's test, univariate and multivariate linear regression, and mixed-model analyses. Results For 59% of patients, the observed variation in baseline FVIII:C was explained by age and genotype. Compared to FVIII:C in patients with Arg612Cys, FVIII:C was significantly different in patients with eight other F8 missense mutations. Intra-individual variation explained 45% of the observed variance in baseline FVIII:C among patients with the same mutation. Conclusion Our results indicate that baseline FVIII:C levels are not exclusively determined by F8 genotype in MHA patients. Insights into other factors may provide potential novel targets for the treatment of MHA.

Prospective study of thromboembolism in 1038 children with acute lymphoblastic leukemia: a Nordic Society of Pediatric Hematology and Oncology (NOPHO) study.

UNLABELLED: ESSENTIALS: Children with acute lymphoblastic leukemia (ALL) are at risk of thromboembolism (TE). This is a prospective evaluation of the incidence, risk factors and outcomes of TE in 1038 children with ALL. TE occurred in 6.1% of children, with the highest incidence (20.5%) among those aged 15-17 years. A TE-associated case fatality of 6.4% indicates that TE is a severe complication of ALL treatment. BACKGROUND: Thromboembolism (TE) is a major toxicity in children with acute lymphoblastic leukemia (ALL) and may have a negative impact on ALL treatment. OBJECTIVES: To examine the cumulative incidence, outcomes and risk factors associated with TE in children with leukemia. PATIENTS/METHODS: We prospectively evaluated TE in 1038 Nordic children and adolescents (≥ 1 and < 18 years) diagnosed with ALL during 2008-2013 and treated according to the NOPHO (Nordic Society of Pediatric Hematology and Oncology)-ALL 2008 protocol. The cohort was followed until December 2014. Cox proportional regression was used to compute hazard ratios (HRs). RESULTS: TE events (n = 63) occurred most frequently in conjunction with asparaginase (ASP) administration (52/63). The cumulative incidence of TE was 6.1% (95% confidence interval [CI], 4.8-7.7). Being aged 15-17 years was associated with an increased risk of TE (adjusted HR of 4.0; 95% CI, 2.1-7.7). We found a TE-associated 30-day case fatality of 6.4% (95% CI, 1.8-15.5) and TE-related truncation of ASP therapy in 36.2% (21/58). Major hemorrhage occurred in 3.5% (2/58) of anticoagulated patients. Minor hemorrhage was reported in two out of 58 patients. No major bleeds occurred in children who received low-molecular-weight heparin. CONCLUSIONS: Methods to identify children and adolescents who will benefit from thromboprophylaxis during ALL treatment are called for. The truncation of ASP should be avoided. The long-term survival outcomes for ALL patients with TE require close monitoring in the future.

In vivo purging of bone marrow in children with poor-risk neuroblastoma for marrow collection and autologous bone marrow transplantation.

PURPOSE: To evaluate the following prospectively in poor-risk neuroblastoma (NBL) patients: (1) the feasibility and efficacy of in vivo purging of bone marrow; and (2) the outcome after autologous bone marrow transplantation (ABMT) when immunologically tumor-free, unpurged autografts were used. PATIENTS AND METHODS: Twenty-three children with poor-risk NBL were evaluated during induction chemotherapy by repeat bone marrow examinations, including aspirate, biopsy, and an immunofluorescence method using the anti-GD2 monoclonal antibody 3A7. Nineteen patients completed the program with surgery with or without local irradiation followed by ABMT. RESULTS: Autologous bone marrow grafts, both immunologically and cytologically clean, were obtained and used in 19 of 23 children. The overall 4-year disease-free survival of the 19 grafted children was 53%, with a toxic death rate of 16% and a posttransplant relapse rate of 37%. According to the in vivo purging efficacy of the 18 children with initial marrow disease, the following three groups were formed: patients with (1) perfect in vivo purging (n = 5); (2) eventually successful in vivo purging (n = 8); and (3) unsuccesful in vivo purging (n = 5). The 4-year DFS was 100%, 67%, and 0%, respectively (P < 0.001). The five patients with unsuccessful in vivo purging failed because of resistant/progressive bulky disease. CONCLUSION: In patients with poor-risk NBL, in vivo purging of bone marrow by conventional chemotherapy is feasible, can be monitored, and the purging efficacy during the first 3 months after diagnosis is a strong prognostic factor reflecting tumor responsiveness to therapy. Autografting with immunologically clean, unpurged marrows gives a DFS well comparable to previous studies using ex vivo purging.

Improving outcome through two decades in childhood ALL in the Nordic countries: the impact of high-dose methotrexate in the reduction of CNS irradiation. Nordic Society of Pediatric Haematology and Oncology (NOPHO).

In this population-based material from the five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden), 2860 children below 15 years of age were diagnosed with acute lymphoblastic leukemia (ALL) from July 1981 to June 1998. The annual incidence was 3.9/100,000 children and was stable throughout the study period. The development from regional or national protocols to common Nordic treatment protocols for all risk groups was completed in 1992 through a successive intensification with multidrug chemotherapy, including pulses of methotrexate in high doses and avoidance of cranial irradiation in most children. The overall event-free survival (EFS) at 5 years has increased from 56.5 +/- 1.7% in the early 1980s to 77.6 +/- 1.4% during the 1990s. The main improvements were seen in children with non-high risk leukemia. In high-risk patients, progress has been moderate, especially in children with high WBC (> or =100 x 10(9)/l) at diagnosis. During the last time period (January 1992-June 1998), only 10% of the patients have received cranial irradiation in first remission, while 90% of the patients have received pulses of high dose methotrexate (5-8 g/m2) isolated or combined with high-dose cytosine arabinoside (total dose 12 g/m2) plus multiple intrathecal injections of methotrexate as CNS-targeted treatment, not translating into increased cumulative incidence of CNS relapse.

Deletion of the Ink4-locus (the p16ink4a, p14ARF and p15ink4b genes) predicts relapse in children with ALL treated according to the Nordic protocols NOPHO-86 and NOPHO-92.

Inactivation of the Ink4 gene locus locus on 9p comprising the tumour suppressor gene p16ink4a and its neighbours p14ARF and p15ink4b is common in childhood acute lymphoblastic leukaemia (ALL), but the prognostic significance is controversial. DNA from 230 patients was retrospectively analysed by Southern blotting, single strand conformation polymorphism (SSCP) and sequencing techniques. The results were correlated with clinical characteristics and outcome. One hundred and ninety-four fully analysed patients, similarly treated using the Nordic NOPHO-86 or the current NOPHO-92 protocols, were included in the outcome analysis. Deletions approached a minimally deleted region between the p16ink4a and p15ink4b genes, making the p14ARF gene the most commonly deleted coding sequence. Bi-allelic deletion was associated with high white blood cell count (WBC) (P < 0.001), T cell phenotype (P < 0.001) and mediastinal mass (P < 0.001). Patients with Ink4 locus bi-allelic deletions had an inferior pEFS (P < 0.01) and multivariate analysis indicated that bi-allelic deletion of the p16ink4a and the p14ARF genes was an independent prognostic risk factor (P < 0.05). Sub-group analysis revealed a pronounced impact of deletion status for high-risk patients, ie with high WBC. Deletion-status and clinical risk criteria (WBC) could thus be combined to further differentiate risk within the high-risk group. The analysis of the Ink4 locus adds independent prognostic information in childhood ALL treated by Nordic protocols and may help in selection of patients for alternative treatment.

Recombinant human granulocyte-macrophage colony-stimulating factor in the treatment of febrile neutropenia: a double blind placebo-controlled study in children.

In a double blind study of 58 episodes of fever and profound neutropenia, children with cancer received either recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) or placebo, combined with identical antimicrobial therapy, i.e. imipenem, on admission. The criteria for discontinuation of therapy were identical. A difference was demonstrated both in the number of hospital days, totaling 252 days in the rhGM-CSF group and 354 in the placebo group, days receiving antibiotics (220 vs. 322), and in the resolution of neutropenia (4.5 days vs. 6.0 days; P < 0.05). The number of episodes requiring antimicrobial therapy for longer than 10 days was 5 of 28 (12%) in the rhGM-CSF group as opposed to 15 of 30 (50%) in the placebo group (P = 0.01). rhGM-CSF was well-tolerated. We conclude that rhGM-CSF was efficacious in accelerating myeloid recovery and reducing the length of hospitalization in febrile neutropenia.

High-dose thiotepa with autologous bone marrow rescue in pediatric solid tumors.

High-dose thiotepa was given as a single agent at a total dose of 1125 mg/m2 with autologous bone marrow rescue to nine patients with recurrent/refractory/poor risk pediatric malignancies (primitive neuroepithelial tumor (PNET), two; neuroblastoma, one; Wilms' tumor, one; osteosarcoma, one; Ewing's sarcoma one, Hodgkin's disease one, high-grade glioma, two). The response rate in these heavily pretreated patients was 71% (five out of seven evaluable patients) including two complete responses (Wilms', glioma), three partial responses (osteosarcoma, Ewing's sarcoma, Hodgkin's disease), and two with stable disease (PNET, glioma). The median duration of response was 2.5 months. The extramedullary toxicity was acceptable with symptoms mainly of skin and gastrointestinal tract. The data indicate that high-dose thiotepa is effective in several types of recurrent pediatric solid tumors, and merits further evaluation in combination regimens.

Genetic aberrations in pediatric acute lymphoblastic leukemia by comparative genomic hybridization.

Classical cytogenetic analysis plays an important role in the diagnosis and classification of childhood acute lymphoblastic leukemia (ALL). However, poor in vitro growth of the malignant cells and suboptimal quality of metaphase spreads may sometimes cause false-negative findings (normal karyotype). We used comparative genomic hybridization (CGH) to study whether this new method is able to detect and characterize genetic aberrations not detected by karyotyping. CGH showed clonal genetic aberrations in 8 of 13 cases, most of which showed gains of several chromosomes, indicating hyperdiploidy. The sensitivity of CGH was sufficient to detect a small interstitial deletion of 6q. One karyotypically complex case was resolved by CGH showing a high-level amplification of DNA sequences originating from the 12p12-13. Interphase fluorescence in situ hybridization (FISH) analyses confirmed the CGH findings in 2 cases, validating the accuracy of CGH. In conclusion, CGH experiments established the known fact that hyperdiploidy is the most common finding in pediatric ALLs and that CGH may detect aberrations that are not seen in the G-banded karyotype. CGH was also able to further characterize genetic aberrations such as gene amplification, which is occasionally involved in pediatric ALL as well as in other leukemias.

Oral health care in children with haemophilia in Helsinki, Finland.

BACKGROUND: The bleeding tendency and fear of bleeds may have a negative effect on preventive dental care of patients with haemophilia both at home and at dental appointments. AIM: To describe the clinical practice of dental care in children with haemophilia in Helsinki, Finland. METHODS: This study evaluated retrospectively the medical records of 28 paediatric patients with haemophilia (aged 5.3-17.4 years) from dental visits during 2009-2010. Decayed, missing and filled teeth in the primary (dmft) and permanent dentition (DMFT), Community Periodontal Index (CPI), signs of developmental dental defects in enamel and the number of preventive and restorative procedures were gathered. Dmft + DMFT scores were compared with those of 17,079 non-haemophiliac boys. The Mann-Whitney U-test was used to compare the data between the groups of different severity of haemophilia. RESULTS: The median number of dental visits per patient was three (range 1-11). Twenty-two patients (79 %) had dmft + DMFT-scores within the 95 % reference range for age. None of the children had a CPI >2. Twelve (43 %) patients had developmental enamel defects. Half had received restorative dental care and three out of four preventive procedures. CONCLUSIONS: Dental care during hospital visits in children with haemophilia may enhance confidence in the preventive dental care and help minimise bleeding during dental procedures.

Long-term quality of life and psychosocial coping after treatment of solid tumours in childhood. A population-based study of 94 patients 11-28 years after their diagnosis.

In order to assess the long-term quality of life after childhood cancer, we examined and interviewed 94 survivors of childhood solid tumours (excluding brain tumors) diagnosed in our hospital between 1960 and 1976. Their follow-up times ranged form 10.7 to 27.7 years, and their ages at the time of this study form 11.3 to 41.5 years. The subjects had a higher educational level than the Finnish general population. Fewer of the females and as many of the males were married as in the general population. Eight healthy men had been rejected for military service because of the history of cancer. An unsatisfied desire to know more about their own medical history was evident. According to our findings, some subjects after childhood solid tumour are at risk of developing emotional and social problems. However, the great majority of the survivors were well balanced psychologically, living a normal social life and showing adequate capacity to cope.

Intra-abdominal bleeding in a 14-year-old girl with acute immune thrombocytopenic purpura.

We describe a 14-year-old girl with acute immune thrombocytopenic purpura. She presented with acute abdominal pain, and her hematocrit decreased from 44% to 29%. The bleeding was due to the rupture of a distended follicle on about the 14th day of her menstrual cycle. The patient's low platelet count made possible the continuous oozing of blood from the follicle into the abdominal cavity, causing peritoneal irritation and the fall in hematocrit. She received treatment with intravenous Ig. This case indicates that unnecessary surgery can be avoided if there is reason to believe that the cause of internal bleeding does not require surgical intervention.