Acute lymphoblastic leukaemia (ALL) is the most common paediatric malignancy and remains one of the most common causes of cancer-related death in children and adolescents. Five-year overall survival rates now exceed 90% with current multidrug chemotherapeutic regimens. This improvement, coupled with the toxicity of chemotherapy, has led to the mortality from treatment-related toxicity approaching rates that are associated with relapse. This manuscript reviews the imaging features of the common treatment-associated abdominal complications in children with ALL.

Importance:Catheter dislodgement is a common complication for children with tunneled or peripherally inserted noncuffed central venous catheters (CVCs). A subcutaneous anchor securement system (SASS) may reduce this risk compared with traditional adhesive securement. Objective:To compare dislodgement of noncuffed CVCs secured with SASS with dislodgement of noncuffed CVCs secured with sutureless securement devices (SSDs). Design, Setting, and Participants:The SECURED (Securing Central Venous Catheters to Prevent Dislodegment) trial was a pragmatic, multicenter, superiority randomized clinical trial with an internal pilot and was conducted from August 5, 2020, to August 30, 2022, at 2 Australian quaternary pediatric hospitals. Data analysis was performed in January 2023. Patients aged 0 to 18 years requiring a noncuffed CVC (≥3F catheter) were eligible for inclusion. Follow-up duration was 8 weeks or until device removal. Interventions:Patients were randomly assigned 1:1 to receive an SASS or SSD, stratified by hospital and catheter type. Only 1 catheter was studied per patient. Main Outcomes and Measures:The primary outcome was dislodgement (partial or total), defined as movement of the catheter tip by greater than 1 cm (change in external catheter length) at any point during catheter dwell. Dislodgement, reported as a risk ratio (RR), was estimated using a generalized linear model with binomial family and log link. Secondary outcomes were reported as incidence rate ratios and were analyzed using Poission regression. Outcomes reported as mean differences (MDs) were analyzed using linear regression. Results:Of 310 randomized patients, 175 patients (56.5%) were male and median (IQR) patient age was 48 (16-120) months. A total of 307 patients had a catheter device inserted, of which 153 (49.8%) were SASS and 154 (50.2%) were SSD, and were included in the intention-to-treat (ITT) analysis. Device dislodgement was lower with SASS (8 dislodgements in 153 patients [5.2%]) compared with SSD (35 dislodgements in 154 patients [22.7%]) (RR, 0.23; 95% CI, 0.11-0.48; P < .001). The per-protocol analysis was consistent with the ITT analysis. Partial dislodgement accounted for most dislodgement events, including 6 partial dislodgements in the SASS group (3.9%) and 30 partial dislodgements in the SSD group (19.5%) (RR, 0.18; 95% CI, 0.08-0.42). This contributed to fewer complications during dwell in the SASS group (37 reported complications [24.2%]) vs the SSD group (60 reported complications [39.0%]) (RR, 0.62; 95% CI, 0.44-0.87). Staff reported greater difficulty removing devices anchored with SASS vs SSD (mean [SD], 29.1 [31.3] vs 5.3 [17.0], respectively; MD, 23.8; 95% CI, 16.7-31.0). However, use of SASS resulted in reduced per-participant health care costs of A$36.60 (95% credible interval, 4.25-68.95; US $24.36; 95% credible interval, 2.83-45.89). Conclusions and Relevance:In the SECURED trial, noncuffed CVCs secured with SASS had fewer dislodgements compared with SSDs, with a lower cost per patient and an acceptable safety profile. Future efforts should be directed at SASS implementation at the health service level. Trial Registration:anzctr.org.au Identifier: ACTRN12620000783921.

Importance Catheter dislodgement is a common complication for children with tunneled or peripherally inserted noncuffed central venous catheters (CVCs). A subcutaneous anchor securement system (SASS) may reduce this risk compared with traditional adhesive securement. Objective To compare dislodgement of noncuffed CVCs secured with SASS with dislodgement of noncuffed CVCs secured with sutureless securement devices (SSDs). Design, Setting, and Participants The SECURED (Securing Central Venous Catheters to Prevent Dislodegment) trial was a pragmatic, multicenter, superiority randomized clinical trial with an internal pilot and was conducted from August 5, 2020, to August 30, 2022, at 2 Australian quaternary pediatric hospitals. Data analysis was performed in January 2023. Patients aged 0 to 18 years requiring a noncuffed CVC (>= 3F catheter) were eligible for inclusion. Follow-up duration was 8 weeks or until device removal. Interventions Patients were randomly assigned 1:1 to receive an SASS or SSD, stratified by hospital and catheter type. Only 1 catheter was studied per patient. Main Outcomes and Measures The primary outcome was dislodgement (partial or total), defined as movement of the catheter tip by greater than 1 cm (change in external catheter length) at any point during catheter dwell. Dislodgement, reported as a risk ratio (RR), was estimated using a generalized linear model with binomial family and log link. Secondary outcomes were reported as incidence rate ratios and were analyzed using Poission regression. Outcomes reported as mean differences (MDs) were analyzed using linear regression. Results Of 310 randomized patients, 175 patients (56.5%) were male and median (IQR) patient age was 48 (16-120) months. A total of 307 patients had a catheter device inserted, of which 153 (49.8%) were SASS and 154 (50.2%) were SSD, and were included in the intention-to-treat (ITT) analysis. Device dislodgement was lower with SASS (8 dislodgements in 153 patients [5.2%]) compared with SSD (35 dislodgements in 154 patients [22.7%]) (RR, 0.23; 95% CI, 0.11-0.48; P < .001). The per-protocol analysis was consistent with the ITT analysis. Partial dislodgement accounted for most dislodgement events, including 6 partial dislodgements in the SASS group (3.9%) and 30 partial dislodgements in the SSD group (19.5%) (RR, 0.18; 95% CI, 0.08-0.42). This contributed to fewer complications during dwell in the SASS group (37 reported complications [24.2%]) vs the SSD group (60 reported complications [39.0%]) (RR, 0.62; 95% CI, 0.44-0.87). Staff reported greater difficulty removing devices anchored with SASS vs SSD (mean [SD], 29.1 [31.3] vs 5.3 [17.0], respectively; MD, 23.8; 95% CI, 16.7-31.0). However, use of SASS resulted in reduced per-participant health care costs of A$36.60 (95% credible interval, 4.25-68.95; US $24.36; 95% credible interval, 2.83-45.89). Conclusions and Relevance In the SECURED trial, noncuffed CVCs secured with SASS had fewer dislodgements compared with SSDs, with a lower cost per patient and an acceptable safety profile. Future efforts should be directed at SASS implementation at the health service level. Trial Registration anzctr.org.au Identifier: ACTRN12620000783921

Background Invasive fungal disease (IFD) can cause significant morbidity in immunocompromised children. The lung is the most common site for IFD caused by moulds. Timely diagnosis is key to facilitate initiation of appropriate treatment. As clinical manifestations are non-specific, initial diagnosis relies on computed tomography (CT) imaging, yet there are limited recent data documenting imaging changes in paediatric pulmonary IFD. In this study, CT images of children with proven/probable pulmonary IFD from two multi-centre cohorts were assessed to document typical changes, including a comparison between causative pathogens, and to measure reliability of radiological reporting in this context. Methods Pulmonary IFD cases diagnosed between 2003-2013 and 2017-2020 were identified from two respective Australian multi-centre cohort studies of immunocompromised children. Proven/probable IFD was defined according to the EORTC/MSG definitions. Initial CT images at the time of IFD diagnosis were independently reviewed by two board-certified paediatric radiologists. Presence of EORTC/MSG-defined and other changes was documented. Inter-rater reliability was assessed. Impact of specific imaging features on outcome at 6 months was assessed using multivariate regression. Results A total of 99 cases were included (65 aspergillosis, 19 non-aspergillus moulds (NAM) and 15 histopathological-mould cases). Median age was 9.6 years (IQR 5.1-13.6); 89.9% had an underlying haematological malignancy. Nodules (85.4%), the halo sign (49.5%) and wedge shaped/segmental consolidation (35.9%) were the most frequent EORTC/MSG-defined features. Cavitation and air-crescent sign were uncommon. Agreement between radiologists was fair to moderate for most common imaging features. No specific radiological finding differentiated aspergillosis from NAM infection. The presence of mass on initial CT and NAM infection were independently associated with poor outcome. Conclusions In proven/probable pulmonary IFD in immunocompromised children, nodules with or without halo sign are the most frequent finding. Agreement between radiologists was variable for common imaging features, and specific findings did not correlate with the causative pathogen. Microbiological confirmation remains vital in children with suspected pulmonary IFD.

HMGA2::NCOR2 keratin-positive giant cell tumors in children with response to imatinib in an infant

Limb-sparing surgery and amputation are common surgical techniques used to achieve local tumour control in childhood primary bone and soft tissue malignancy of the limbs. The interpretation of post-operative limb imaging in these frequently complex cases is assisted by knowledge of the surgical techniques employed. This review discusses the rationale underpinning the most common surgical techniques used for these patients as well as their expected post-operative imaging appearance and complications. Amputation, long bone resection, endoprosthetic reconstruction, allograft reconstruction, the use of fibular autografts, allograft-prosthetic composite reconstruction and arthrodesis are discussed.

Introduction: Staphylococcus aureus bacteraemia (SAB) is the most common cause of sepsis, contributing to paediatric intensive care unit admission in Australia and New Zealand. While deep venous thrombosis (DVT) has been reported in children with invasive S. aureus infections, the actual frequency and possible effects of thrombosis on disease severity and outcome in paediatric SAB remain unknown. Moreover, guidance regarding imaging for paediatric SAB management are poorly defined. Methods and analysis: We report the protocol for the SNOOPY (Staphylococcus aureus Network; ultrasOund for diagnOsis of endovascular disease in Paediatrics and Youth) study. SNOOPY is a pilot prospective single-arm interventional study that aims to investigate the proportion of children with SAB that have venous thrombosis detected using whole body doppler ultrasound.

Traditionally, testicular biopsy is performed using an open surgical approach. Ultrasound-guided percutaneous biopsy is a less invasive alternative and can be performed in children. The aim of this study is to report our technique and to assess the diagnostic accuracy and safety of ultrasound-guided percutaneous biopsy of testicular masses in children. This is a 16-year retrospective review of ultrasound-guided percutaneous testicular biopsies at a single pediatric hospital. We performed nine ultrasound-guided testicular biopsies in 9 patients (median age: 3 years, range: 4 months–11 years; median weight: 20.9 kg, range: 8.4–35 kg; median volume of testicular lesion biopsied: 4.4 mL, range: 1.2–17 mL). A percutaneous co-axial technique was used for 5/9 biopsies with absorbable gelatin sponge tract embolization performed in 4 of those biopsies. A non-co-axial technique was used in 4/9 biopsies. A median of three cores, range 2–6, were obtained. The diagnostic yield was 89

Intravascular tumor extension is an uncommon complication of solid malignancies that, when present in the inferior vena cava (IVC), can result in fatal pulmonary tumor embolism. Currently, neoadjuvant chemotherapy and surgery are the mainstays of treatment; however, there are no consensus guidelines for management. We describe three cases of pediatric solid malignancies with associated IVC extension and pulmonary tumor embolism. We hypothesize that there is scope for IVC filter placement in such cases to mitigate the risk of fatal pulmonary tumor embolism.

## Introduction Catheter dislodgement is a common complication for children with tunneled or peripherally inserted non-cuffed central venous catheters (nc-CVCs). We aimed to compare the effectiveness of a subcutaneous anchored securement system (SASS) with a sutureless securement device (SSD) to prevent CVC dislodgement. ## Materials and Methods Multicenter randomized controlled trial (June 2020 to July 2022) at two Australian quaternary pediatric hospitals, Queensland Children's Hospital, and Perth Children's Hospital. Patients aged neonate to 18 years requiring a peripherally inserted or tunneled, non-cuffed CVC were included. Randomization was 1:1, stratified by device type. The primary outcome was dislodgement. Secondary outcomes included partial or complete dislodgment, catheter-associated skin impairment, dwell time, healthcare costs, and patient, and staff satisfaction. Prospectively registered, Australia New Zealand Clinical Trials Registry, ACTRN12620000783921, Hospital (HREC/20/QCHQ/62034) and University (2020/368) ethics approval. ## Results Of 310 randomized patients, 307 (median [IQR] age, 48[16-120] months; 175 males [56%]) had a device inserted, 153 (49.8%) SASS and 154 (50.2%) SSD and were included in the intention to treat analysis. Device dislodgement was lower with SASS (8 [5.2%]) compared to SSD (35[22.7%]); risk ratio [RR], 0.23; 95% confidence interval [CI], 0.11-0.48; P <0.001. The per protocol analysis were consistent with intention to treat. Partial dislodgement accounted for most dislodgement events 6 [3.9%] SASS vs 33 [21.4%] SSD; RR, 0.18; 95% CI, 0.08-0.42, contributing to fewer complications during dwell in SASS (37 [24.2%]) vs SSD (60 [39.0%]; RR 0.62, 95% CI, 0.44 to 0.87). Staff reported greater difficulty removing SASS (mean [standard deviation], 29.1[31.3]) vs. SSD (5.3[17.0]; mean difference 23.8; 95% CI, 16.7 to 31.0), however use of SASS resulted in lower healthcare costs AU$36.60 per participant; 95% credible interval, AU$4.73 to AU$69.85. ## Discussion In this pediatric, multicenter, randomized controlled trial, we demonstrated a significant reduction in nc-CVC dislodgement with SASS securement compared to SSD standard care. SASS's greater strength, achieved by deep tissue adherence, ensures securement against environmental challenges like moisture or sweat. Our results have immediate implications for maintaining CVC function in children with severe diseases, as dislodgement is the greatest threat to catheter survival in pediatrics. Additionally, SASS securement reduced CLABSI rates and local infections compared to SSD, aligning with findings from previous studies. Despite staff reporting increased difficulty in removing SASS, the securement method resulted in significant cost savings and potential for greater efficiency in larger healthcare facilities. Further research should focus on staff education and dedicated implementation and evaluation of this novel securement product, particularly in generalist healthcare systems.

Background A first febrile urinary tract infection (UTI) is a common condition in children, and pathways of management have evolved over time. Objective To determine the extent to which pediatricians and surgeons differ in their investigation and management of a first febrile UTI, and to evaluate the justifications for any divergence of approach. Materials and methods A literature search was conducted for papers addressing investigation and/or management following a first febrile UTI in children published between 2011 and 2021. Searches were conducted on Medline, Embase, and the Cochrane Controlled Trials Register. To be eligible for inclusion, a paper was required to provide recommendations on one or more of the following: ultrasound (US) and voiding cystourethrogram (VCUG), the need for continuous antibiotic prophylaxis and surgery when vesicoureteral reflux (VUR) was detected. The authorship required at least one pediatrician or surgeon. Authorship was categorized as medical, surgical, or combined. Results Pediatricians advocated less imaging and intervention and were more inclined to adopt a “watchful-waiting” approach, confident that any significant abnormality, grades IV–V VUR in particular, should be detected following a second febrile UTI. In contrast, surgeons were more likely to recommend imaging to detect VUR ( p <0.00001), and antibiotic prophylaxis ( p <0.001) and/or surgical correction ( p =0.004) if it was detected, concerned that any delay in diagnosis and treatment could place the child at risk of kidney damage. Papers with combined authorship displayed intermediate results. Conclusion There are two distinct directions in the literature regarding the investigation of an uncomplicated first febrile UTI in a child. In general, when presented with a first febrile UTI in a child, physicians recommend fewer investigations and less treatment, in contrast to surgeons who advocate extensive investigation and aggressive intervention in the event that imaging detects an abnormality. This has the potential to confuse the carers of affected children.

Presented here is a very rare and potentially life-threatening complication of a very common procedure. Vascular injury with traumatic pseudoaneurysm following BMAT in a paediatric patient has only been reported once in the literature to the best of our knowledge. Presented here is a second case, with pathognomonic imaging findings on CT that underwent successful coil embolisation.

Tuberous sclerosis complex(TSC)is an autosomal dominant disease caused by inactivating germline mutations in TSC1 or TSC2.These genes code for hamartin and tuberin,pro-teins that normally form a complex that down-regulates the mechanistic(or mammalian)target of rapamycin(mTOR)pathway,which is crucial to cell growth,proliferation and survival.The phenotypic effects of TSC include abnormali-ties in the brain,kidneys,skin,heart and lungs.Renal mani-festations include cyst formation and the development of tumors,especially multiple benign tumors called angiomy-olipomas(AMLs)as well as renal cell carcinoma(RCC)and oncocytoma[1].Almost all renal masses in children with TSC are AMLs,and these can often be confidently diag-nosed by imaging,most often by the identification of sig-nificant fatty components on computed tomography(CT)or magnetic resonance imaging(MRI).Occasionally,however,even a large AML will contain no identifiable fatty elements.

Histiocytoses are rare multi-system disorders marked by abnormal histiocyte cell proliferation, affecting children with diverse clinical presentations. Classified into five groups in 2016, including Langerhans-related (L), cutaneous (C), malignant (M), Rosai-Dorfman disease (R) and haemophagocytic lymphohistiocytosis (H), newer entities such as ALK-positive histiocytosis have also emerged, heralding the era of molecular (sub)classification. Common entities include Langerhans cell histiocytosis (LCH), Erdheim-Chester disease (ECD), Rosai-Dorfman disease (RDD) and haemophagocytic lymphohistiocytosis (HLH). This pictorial essay aids radiologists in recognising and differentiating paediatric histiocytoses based on unique neuroimaging features.

To determine the management and outcomes of patients with gastro-oesophageal reflux (GOR) that requires further intervention following failure of Nissen fundoplication (NF). After institutional audit department approval, a retrospective review of paediatric patients who had further intervention following failure of primary NF between January 2006 and December 2015 for GOR at our centre was performed. Data are presented as median (range). Of 820 patients who underwent NF, 190 (23%) received further procedures for GOR management at a median of 21 months of age (6–186); 90/190 (47%) had gastro-jejunal feeding (GJ). Of these, 67 (74%) remained on GJ feeds up to a median of 48 months and 23/90 (26%) had a second NF after GJ feeding. 97/190 (51%) had a redo fundoplication without having had a GJ; thus, 120/190 (63%) of patients having a further procedure went on to have a second NF after a median period of 15 months (1–70 months). Three patients (2%) had early emergency wrap revision 4 days after first fundoplication (we classed this as an ‘early complication’). Of the seven patients who failed a 3rd NF, 4 continued GJ feeding, 2 of had oesophagogastric dissociation; 2 had 4th NF of which 1 was successful and 1 patient had gastric pacemaker and is successfully feeding orally. Patients who were finally successfully managed with GJ underwent 2 (2–5) tube changes/year. We found patients who had a previous GJ were more likely to have failure of the redo fundoplication than those who had not to have the GJ (16/24 vs. 30/90, p = 0.005). The chance of success decreases with every further attempt at fundoplication. The only factor significantly associated with failure of redo fundoplication was whether the patient previously had a GJ tube. In patients with failed fundoplications, when symptom free on jejunal feedings, further anti-reflux surgical intervention should be avoided. A randomized prospective study is needed for patient selection.

Renovascular hypertension in most cases requires endovascular treatment and/or surgery. This is technically much more difficult in small children and there is very limited published knowledge in this age group. We here present treatment and outcome of young children with renovascular hypertension at our institution. Children below 2 years of age, with renovascular hypertension between January 1998 and March 2020 were retrospectively reviewed. Demographics and treatment modalities were noted. Primary outcome was blood pressure within a week after the procedures and at last available visit. Sixty-six angiographies were performed in 34 patients. Median age at time of first angiography was 1.03 (interquartile range (IQR) 0.4–1.4) years and systolic blood pressure at presentation 130 (IQR 130–150) mm Hg. Thirty-eight percent (13/34) of children were incidentally diagnosed and 18% (6/34) presented with heart failure. Twenty-six (76%) children had main renal artery stenosis and 17 (50%) mid-aortic syndrome. Seventeen (50%) children showed intrarenal, six (18%) mesenteric, and three (9%) cerebrovascular involvement. Twenty patients underwent 45 percutaneous transluminal angioplasty procedures and seven children surgeries. In 44% of the 16 patients who underwent only percutaneous transluminal angioplasty blood pressure was normalized, 38% had improvement on same or decreased treatment and 19% showed no improvement. Complications were seen in 7.5% (5/66) of angiographies. In four of the seven (57%) children who underwent surgery blood pressure was normalized, two had improved (29%) and one unchanged (14%) blood pressure. Conclusion: In small children with renovascular hypertension below the age of 2 years, percutaneous transluminal angioplasty caused significant improvement in blood pressure with low complication profile. Surgery can be recommended where percutaneous transluminal angioplasty and medical treatments failed.