ALK-positive histiocytosis: an expanded clinicopathologic spectrum and frequent presence of KIF5B-ALK fusion.

In 2008, we presented three cases of ALK-positive histiocytosis as a novel systemic histiocytic proliferation of early infancy with hepatosplenomegaly and dramatic hematological disturbances. This series of 10 cases (including the original three cases) describes an expanded clinicopathological spectrum and the molecular findings of this histiocytic proliferation. Six patients had disseminated disease: five presented in early infancy with eventual disease resolution, and the sixth presented at 2 years of age and died of intestinal, bone marrow, and brain involvement. The other four patients had localized disease involving nasal skin, foot, breast, and intracranial cavernous sinus - the first three had no recurrence after surgical resection, while the cavernous sinus lesion showed complete resolution with crizotinib therapy. The lesional histiocytes were very large, with irregularly folded nuclei, fine chromatin, and abundant eosinophilic cytoplasm, sometimes with emperipolesis. There could be an increase in foamy histiocytes and Touton giant cells with time, resembling juvenile xanthogranuloma. Immunostaining showed that the histiocytes were positive for ALK, histiocytic markers (CD68, CD163) and variably S100, while being negative for CD1a, CD207, and BRAF-V600E. Next-generation sequencing-based anchored multiplex PCR (Archer® FusionPlex®) performed in six cases identified KIF5B-ALK gene fusion in five and COL1A2-ALK fusion in one. There was no correlation of gene fusion type with disease localization or dissemination. The clinicopathological spectrum of ALK-positive histiocytosis is broader than originally described, and this entity is characterized by frequent presence of KIF5B-ALK gene fusion. We recommend that every unusual histiocytic proliferative disorder, especially disseminated lesions, be tested for ALK expression because of the potential efficacy of ALK inhibitor therapy in unresectable or disseminated disease.

Narrative historical review of scratch-and-sniff books and their key storytelling features.

This conceptual paper examines the use of odours and scents in books to enhance storytelling and engage readers. While books often possess a distinctive smell linked to their material production, the intentional use of scents in books is rare. Our study focuses on scratch-and-sniff books, examining their narrative purposes and contributions to young children's literature. We conduct a narrative historical review, supplemented by a systematic search of databases, online catalogues and lists, to identify a collection of these scented books. Through this review, we explore the extent to which these books represent a unique category of children's picture books, investigating how their features align with theoretical understandings of quality characteristics in children's literature and the role of olfactory cues in storytelling. We address why most scented books target younger readers and discuss possible reasons for the absence of scented books for an adult readership. This intriguing asymmetry contrasts the use of scent in other media (such as film, theatre or virtual reality), often directed toward adults. In addition, this review sheds light on the innovative use of scents in books and their impact on reader immersion and narrative experience. Finally, we consider possible future uses of scent in the context of digital books (ebooks).

Continuous reference intervals for holotranscobalamin, homocysteine and folate in a healthy paediatric cohort.

BACKGROUND: The detection of deficiencies in B12 and folate children is important. However, despite the availability of various markers to assess B12 and folate metabolism, there are limited studies describing the reference intervals (RIs) and changes during growth and development for these markers in healthy children. METHODS: Using samples collected from 378 children aged 30 days-< 18 years, we derived continuous RIs for holotranscobalamin, homocysteine and red cell folate. RESULTS: The lower RI for holotranscobalamin was lowest at birth, rising during early childhood and then declining following ages 4-6 years whereas red cell folate was highest early in life and then declined steadily towards adulthood. Total homocysteine, reflective of both B12 and folate status was elevated early in life, reaching a nadir at age 2 and then increasing towards adulthood. CONCLUSIONS: Continuous central 95th percentile RI for holotranscobalamin, homocysteine and red cell folate for children ages 30 days to <18 years were established. Each marker shows dynamic changes throughout childhood and adolescence which will assist clinicians in more appropriately assessing B12 and folate status in this population.

Laboratory validation and clinical utility of next-generation sequencing-based IGH/TCR clonality testing for the monitoring of measurable residual disease in acute lymphoblastic leukaemia: real-world experience at Austin Pathology.

Measurable residual disease (MRD) testing is an essential aspect of disease prognostication in acute lymphoblastic leukaemia (ALL) and informs clinical decisions. The depth of MRD clearance is highly relevant and requires assays with sufficient sensitivity. Austin Pathology is one of the few laboratories in Australia currently utilising a fully validated and National Association of Testing Authorities (NATA)-accredited ultrasensitive next-generation sequencing (NGS) platform for MRD monitoring in ALL. This technology is based on the detection of clonal rearrangement of immunoglobulin and T cell receptor genes in leukaemic cells, and is capable of achieving a limit of detection at least one to two logs below that of multiparametric flow cytometry (MFC). In this retrospective analysis, we report a clonotype detection rate of up to 85.7% at diagnosis, and a concordance rate of 78.7% in MRD results between NGS and MFC. Of the discordant samples, nearly all were NGS+/MFC-, highlighting the superior sensitivity of NGS. The enhanced sensitivity is clinically relevant, as discordant MRD results often heralded fulminant relapse, and therefore offer clinicians additional lead time and a window of opportunity to initiate pre-emptive therapy. Notwithstanding a small and heterogeneous cohort, our real-world survival data indicate an intermediate relapse risk for NGS+/MFC- patients. In light of recent approval of Medicare rebatable ALL MRD testing, we discuss how NGS can complement other techniques such as MFC in personalising management strategies. We recommend routine clonality testing by NGS at diagnosis and use a multi-modality approach for subsequent MRD monitoring.

Alectinib induces marked red cell spheroacanthocytosis in a near-ubiquitous fashion and is associated with reduced eosin-5-maleimide binding.

We reviewed haematological investigations for 43 patients treated at a single centre with alectinib, an inhibitor of anaplastic lymphoma kinase (ALK) which is considered standard first-line treatment for patients with ALK-rearranged advanced non-small cell lung cancer. Ninety-five percent of patients developed marked acanthocytosis, echinocytosis and/or spheroacanthocytosis, not observable with prior treatment with other ALK-inhibitors. Anaemia developed in 73% of patients (38% <100 g/L, 8% <80 g/L), though definite new haemolysis was present in only 11%. Eosin-5-maleimide binding was reduced in all assessed patients, and increased membrane cholesterol was identified in one patient assessed with lattice light sheet microscopy. We have identified a previously undescribed phenomenon whereby alectinib induces red cell membrane abnormalities in nearly all patients through an unclear, but likely ALK-independent, mechanism, resulting in mild anaemia without universal haemolysis.

Arterial thromboembolic disease: a single-centre case series study.

AIM: Paediatric venous thromboembolic disease has been reported with increased frequency during the last decade. In contrast, the pathophysiology of arterial thromboembolic disease in infants and children has not been adequately explored. The aim of this study was to determine the prevalence, aetiology, diagnostic criteria, management and outcome of arterial thromboembolism (TE) in a tertiary paediatric centre. METHODS: A prospective, single-centre registry was established at an Australian tertiary paediatric centre in order to address the aim of this study. RESULTS: One-hundred-and-two arterial thrombotic events occurred in 98 patients during 48 months. Infants were most likely to have a lower limb arterial TE (n = 22) whilst children were most likely to have a central nervous system arterial TE (n = 26). Surgery was a frequent predisposing factor in both infants and children. Doppler ultrasonography, computerized tomography and magnetic resonance imaging were the most commonly used diagnostic modalities. Unfractionated heparin was the most frequently used treatment in both age groups. At discharge, 25 infants and twelve children had complete resolution of their arterial TE. Direct thrombosis-related mortality was 4% in infants and 9% in children. Duration of follow-up ranged from 1 to 900 days, with thirteen infants and 32 children never achieving complete resolution. Forty-nine percent of post-discharge survivors had significant long term sequelae directly attributable to their arterial TE. CONCLUSION: Arterial TE occurred as frequently as venous TE in our tertiary paediatric population. The clinical outcome and long term sequelae of such events are significant.

The prevalence of inherited thrombophilic polymorphisms in an asymptomatic Australian antenatal population.

AIM: Inherited thrombophilic polymorphisms have been linked to pregnancy-related thromboembolism and other adverse pregnancy outcomes. As there are limited data on the prevalence of these polymorphisms in Australian populations, we aimed to assess this in an antenatal population. METHODS: Healthy nulliparous women (n = 2031) were recruited to this study. The women had no past or family history of venous thromboembolism. Women were excluded if they or a family member was known to be a carrier of any thrombophilic marker. Genotyping from venous blood for the factor V Leiden, prothrombin 20210A, MTHFR 677 and 1298 and thrombomodulin C1418T polymorphisms was undertaken. RESULTS: Key findings were that 107 of 2019 (5.30, 95% confidence interval 4.36-6.37%) women tested were heterozygous carriers of factor V Leiden and one was homozygous (0.05, 0-0.27%); 2.43% of women were heterozygous carriers of the prothrombin gene mutation (1.80-3.20%) while no women were homozygous for this mutation; 11.62% (10.22-13.02%) and 9.98% (8.67-11.29%) were homozygous for the MTHFR 677 and 1298 polymorphisms, respectively, and 3.43% (2.63-4.22%) of women were homozygous for the thrombomodulin polymorphism. CONCLUSIONS: The prevalence of these polymorphisms is consistent with previously published data in Caucasian populations. These data will provide the basis for further assessment of the relationship between poor pregnancy outcome and these inherited thrombophilic polymorphisms in an asymptomatic antenatal population.

Genetics and blood--haemoglobinopathies and clotting disorders.

BACKGROUND: Genetic disorders of the blood are common inherited conditions of global impact. The haemoglobinopathies and clotting disorders represent two areas of significance to Australian primary care practitioners. OBJECTIVE: This article describes the haemoglobinopathies and thrombophilias and their relevance to primary care practitioners. In particular it describes the role of the general practitioner in identifying who is at risk of being a carrier of, or at risk of developing, these conditions. DISCUSSION: Global migration patterns to Australia have meant that the carrier frequency of haemoglobinopathies has increased in recent years. General practitioners play a key role in carrier screening and ideally should consider screening of couples in pre-pregnancy situations wherever possible. Genetic predisposition to thrombophilias is an important factor regarding the risk of thrombophilias and should be considered as part of the indications for screening.

Anticoagulation in neonates and children: Pitfalls and dilemmas.

Anticoagulation in children is problematic for many reasons, related to the patient population as well as the anticoagulant drugs themselves. This paper describes the multitude of reasons why providing anticoagulation therapy in children is different from anticoagulation therapy in adults, and hence why dedicated paediatric anticoagulant services are the ideal structure to provide this service. The paper then describes the three most common anticoagulants used in children, and details specifically what is and is not known about them in the paediatric population. Finally the paper addresses the issue of how best to introduce newer anticoagulant drugs into the paediatric population. There remains much research to be done in this field, in the meantime clinicians need to carefully consider the evidence available to them and manage each individual patient accordingly.

Evaluation of a post-operative thrombin inhibitor replacement protocol to reduce haemorrhagic and thrombotic complications after paediatric liver transplantation.

INTRODUCTION: Bleeding and thrombotic complications contribute to morbidity and mortality following paediatric orthotopic liver transplantation (OLT). However, the pathophysiology of haemostasis during paediatric OLT is not well understood. This report consists of two complimentary studies examining the frequency of haemostatic complications before and after the introduction of a post-operative thrombin inhibitor replacement therapy protocol at a single institution. MATERIALS AND METHODS: A retrospective study of 40 patients who underwent 43 liver transplants between July 1992 and July 2002, identified bleeding to be the most frequent complication associated with OLT (30%), however thrombotic complications were also common (12.5%). In 2003, following a detailed analysis of haemostatic profiles of children undergoing OLT, a thrombin inhibitor replacement protocol was introduced. A prospective clinical outcome audit was undertaken from April 2003 to September 2008 to determine the effect of the new protocol on haemostasis. RESULTS: Commencement of the thrombin inhibitor replacement protocol significantly reduced the incidence of thrombosis (from 5 to 1, p<0.05), graft loss (from 4 to none, p<0.05), mortality due to thrombosis or bleeding (from 3 to none, p<0.05) and was associated with a 50% reduction in frequency of major bleeding. CONCLUSION: In conclusion, the introduction of a post-operative thrombin inhibitor replacement therapy protocol following paediatric OLT significantly improved haemostasis-related morbidity and mortality outcomes in children.

Assessing the outcome of systemic tissue plasminogen activator for the management of venous and arterial thrombosis in pediatrics.

This study sought to ascertain the outcomes of systemic thrombolytic therapy used in a cohort of infants and children. Complete thrombus resolution was achieved in 81% of patients with arterial thromboses (n=16) compared to 0% of children with venous thromboses (n=10). A major bleeding rate of 11.5% occurred across the entire cohort (n=3, all arterial). In our cohort, no patient with venous thromboembolism achieved complete resolution of their thrombosis after thrombolytic therapy. More cohort studies reporting the outcome of uniform protocols of thrombolytic therapy in children are required.

Venous thromboembolic disease: a single-centre case series study.

AIM: The epidemiology of venous thromboembolism in children has likely changed since first being described a decade ago because of evolving management strategies and a greater awareness of predisposing factors for thrombosis in children. The Royal Children's Hospital commenced a 4-year prospective registry of venous thrombosis in 1999 to determine the current Australian epidemiology of venous thrombosis in infants and children. METHODS: A prospective, single-centre registry was established to determine the prevalence, aetiology, diagnostic criteria, management and outcome of venous thromboembolism in an Australian tertiary paediatric centre. RESULTS: The incidence of venous thrombosis was 8.0/10 000 hospital admissions. Fifty-eight per cent of infants and 49% of children were male. Seventy-seven per cent of venous thromboses in infants were associated with central venous cannulation compared with 47% in children. Doppler ultrasonography was the most frequently used diagnostic tool. Treatment strategies varied between age groups. The all-cause mortality rate for infants and children in this study was 8.4% (direct thrombus-related mortality 0%). Fifteen per cent of all patients demonstrated complete resolution of their venous thrombosis at discharge, with 48% demonstrating complete resolution at follow-up assessment. Fifteen per cent of patients experienced significant thrombosis-related morbidity at follow-up assessment. CONCLUSION: In this single-centre registry, venous thrombosis in infants and children occurred with greater frequency than has previously been reported and its epidemiology varied. Central venous catheterisation continues to be a common precipitant to venous thrombosis. Optimal diagnostic and treatment interventions for venous thromboembolism have not yet been determined for infants and children, despite the significant incidence of long-term sequelae.

The prognostic impact of bone marrow involvement in patients with diffuse large cell lymphoma varies according to the degree of infiltration and presence of discordant marrow involvement.

BACKGROUND: The prognostic significance of marrow involvement in diffuse large cell lymphoma (DLCL) is controversial. Factors that that have been reported to influence prognosis include the pattern and extent of marrow infiltration and histological discordance between the primary site and the bone marrow. METHODS: Bone marrow biopsies from 172 patients with newly diagnosed DLCL entered in two consecutive trials of the Australasian Leukaemia and Lymphoma Group were analyzed. Progression-free (PFS) and overall survival (OS) were calculated according to the absence or presence of bone marrow involvement (BMI), the extent of lymphomatous infiltration and the presence of histological discordance between the primary site and the bone marrow. RESULTS: Of 172 patients with DLCL accrued between 1982 and 1990, who were treated with CHOP or CHOP-like regimens, 47 (27%) demonstrated marrow involvement on examination of multiple levels. Seventy two percent (34/47) of patients had discordant marrow involvement (<50% large cells) and 28 had minimal (<10%) involvement; these latter patients with minimal marrow involvement (<10%) had similar PFS & OS to the 113 patients without involvement. Within the group of 47 patients with marrow involvement, an increasing percentage of BM involvement was significantly associated with an increasing percentage of concordant histology and a decreasing PFS & OS. CONCLUSIONS: Minimal BMI, seen in the majority of patients with DLCL with marrow infiltration, appears not to influence the PFS & OS. However, an increasing degree of marrow involvement is associated with an increasing component of large cells and a poorer prognosis in DLCL patients, independent of other risk factors.

Bleeding disorders in teenagers presenting with menorrhagia.

OBJECTIVE: To assess the prevalence of bleeding disorders and establish the clinical variables that are predictive of a bleeding disorder in adolescent women. DESIGN: A retrospective audit of all patients who had coagulation tests following presentation with menorrhagia. SETTING: Inpatient and outpatients of a tertiary adolescent gynaecology service. PATIENTS: Subjects aged 9-19 years with menorrhagia who had coagulation tests performed, and who did not have a known bleeding disorder prior to presentation were included. OUTCOME MEASURES: A bleeding screen was performed to assess prevalence of bleeding disorders in the population. Variables that were investigated as predictive of a bleeding disorder included clinical history, family history, and haematological indices of blood loss. RESULTS: The prevalence of an inherited bleeding disorder was 10.4%. The only statistically significant predictor was a family history of bruising and bleeding. Menstrual history was not predictive. CONCLUSION: Severity of menstrual loss was not predictive of a bleeding disorder, as a significant cause of teenage metrostaxis is due to anovulatory dysfunctional uterine bleeding. The authors recommend that a careful personal and family history of bruising and bleeding be taken in all teenagers who present de novo with menorrhagia. Routine screening in a primary care setting is impractical, but should be mandatory in all patients with a positive family history.

Warfarin therapy in children who require long-term total parenteral nutrition.

OBJECTIVE: To determine whether warfarin can be safely administered to children who require long-term total parenteral nutrition (TPN), for the purpose of preventing central venous access device (CVAD)-related thrombosis. METHODS: A prospective cohort study was conducted of 8 children with short-gut syndrome or small intestinal anomalies. All patients received oral anticoagulant therapy (warfarin) managed by the hematology department at a tertiary pediatric center. Data collected included demographic details, nutritional intake, age, weight, history of deep vein thrombosis, number and functional duration of CVADs, warfarin requirements, and adverse event rates. RESULTS: A total of 15.2 warfarin years were studied prospectively. The target therapeutic range was achieved 51.1% of time. The mean dose of warfarin required to achieve the target therapeutic range (international normalized ratio) of 2.0 to 3.0 was 0.33 mg/kg/d. The mean duration between warfarin monitoring tests was 6.6 days. The median vitamin K intake per patient was 0.367 mg/kg/d (range: 0.018-2.85 mg/kg/d). Before commencing anticoagulant therapy, the mean CVAD duration was 160.9 days. Concomitant warfarin therapy was associated with a mean CVAD duration of 351.7 days. There were no major bleeding events, and no clinical extension of thrombosis was observed. CONCLUSIONS: This is the first published study to report uniform warfarin prophylaxis for CVADs in children. Warfarin therapy can be administered safely in children who require long-term TPN. Warfarin prophylaxis seems to prolong CVAD survival.