Abdominal Coarctation and Associated Comorbidities in Children

Real-World Biomarkers for Pediatric Takayasu Arteritis

Childhood-onset Takayasu arteritis (TA) is a rare, heterogeneous disease with limited diagnostic markers. Our objective was to identify and classify all candidates for biomarkers of TA diagnosis in children reported in the literature. A systematic literature review (PRISMA) of MEDLINE, EMBASE, Wiley Cochrane Library, ClinicalTrias.gov, and WHO ICTRP for articles related to TA in the pediatric age group between January 2000 and August 2023 was performed. Data on demographics, clinical features, laboratory measurements, diagnostic imaging, and genetic analysis were extracted. We identified 2026 potential articles, of which 52 studies (81% case series) met inclusion criteria. A total of 1067 TA patients were included with a peak onset between 10 and 15 years. Childhood-onset TA predominantly presented with cardiovascular, constitutional, and neurological symptoms. Laboratory parameters exhibited a low sensitivity and specificity. Imaging predominantly revealed involvement of the abdominal aorta and renal arteries, with magnetic resonance angiography (MRA) being the preferred imaging modality. Our review confirms the heterogeneous presentation of childhood-onset TA, posing significant challenges to recognition and timely diagnosis. Collaborative, multinational efforts are essential to better understand the natural course of childhood-onset TA and to identify accurate biomarkers to enhance diagnosis and disease management, ultimately improving patient outcomes.

Mosaic RAS/MAPK variants cause sporadic vascular malformations which respond to targeted therapy

BACKGROUND. Sporadic vascular malformations (VMs) are complex congenital anomalies of blood vessels that lead to stroke, life-threatening bleeds, disfigurement, overgrowth, and/or pain. Therapeutic options are severely limited, and multidisciplinary management remains challenging, particularly for high-flow arteriovenous malformations (AVM).

METHODS. To investigate the pathogenesis of sporadic intracranial and extracranial VMs in 160 children in which known genetic causes had been excluded, we sequenced DNA from affected tissue and optimized analysis for detection of low mutant allele frequency.

RESULTS. We discovered multiple mosaic-activating variants in 4 genes of the RAS/MAPK pathway, KRAS, NRAS, BRAF, and MAP2K1, a pathway commonly activated in cancer and responsible for the germline RAS-opathies. These variants were more frequent in high-flow than low-flow VMs. In vitro characterization and 2 transgenic zebrafish AVM models that recapitulated the human phenotype validated the pathogenesis of the mutant alleles. Importantly, treatment of AVM-BRAF mutant zebrafish with the BRAF inhibitor vemurafinib restored blood flow in AVM.

CONCLUSION. Our findings uncover a major cause of sporadic VMs of different clinical types and thereby offer the potential of personalized medical treatment by repurposing existing licensed cancer therapies.

FUNDING. This work was funded or supported by grants from the AVM Butterfly Charity, the Wellcome Trust (UK), the Medical Research Council (UK), the UK National Institute for Health Research, the L’Oreal-Melanoma Research Alliance, the European Research Council, and the National Human Genome Research Institute (US).

A rare cause of cardiomyopathy in an infant: middle aortic syndrome

Coarctation of the abdominal aorta is a rare condition with a handful of cases reported in infancy. We report the case of a 4-month-old infant with severe abdominal coarctation who presented with dilated cardiomyopathy. Following successful transcatheter-based stenting of her abdominal aorta, her cardiomyopathy resolved.

Disease Beyond the Arch: A Systematic Review of Middle Aortic Syndrome in Childhood

BACKGROUND

Middle aortic syndrome (MAS) is a rare clinical entity in childhood, characterized by a severe narrowing of the distal thoracic and/or abdominal aorta, and associated with significant morbidity and mortality. MAS remains a relatively poorly defined disease. This paper systematically reviews the current knowledge on MAS with respect to etiology, clinical impact, and therapeutic options.

METHODS

A systematic search of 3 databases (Embase, MEDLINE, and Cochrane Central Register of Controlled Trials) yielded 1,252 abstracts that were screened based on eligibility criteria resulting in 184 full-text articles with 630 reported cases of childhood MAS. Data extracted included patient characteristics, clinical presentation, vascular phenotype, management, and outcomes.

RESULTS

Most cases of MAS are idiopathic (64%), 15% are associated with Mendelian disorders, and 17% are related to inflammatory diseases. Extra-aortic involvement including renal (70%), superior mesenteric (30%), and celiac (22%) arteries is common, especially among those with associated Mendelian disorders. Inferior mesenteric artery involvement is almost never reported. The majority of cases (72%) undergo endovascular or surgical management with residual hypertension reported in 34% of cases, requiring medication or reintervention. Clinical manifestations and extent of extra-aortic involvement are lacking.

CONCLUSIONS

MAS presents with significant involvement of visceral arteries with over two thirds of cases having renal artery stenosis, and one third with superior mesenteric artery stenosis. The extent of disease is worse among those with genetic and inflammatory conditions. Further studies are needed to better understand etiology, long-term effectiveness of treatment, and to determine the optimal management of this potentially devastating condition.

[Late complications and treatment options of aortic coarctation operated in childhood]

INTRODUCTION

The prevalence of congenital aortic coarctation is 4 in 10 000 live birth. Aortic coarctation is typically located in the aortic isthmus, but it may occur at atypical sites. Treatment options include both surgical and endovascular interventions. In patients undergoing surgical or endovascular intervention late complications such as recoarctation or aortic aneurysm may develop.

AIM

The aim of the authors was to analyse their own experience in late complication and treatment options of aortic coarctation operated in childhood.

METHOD

Retrospective analysis of data of 32 patients treated between 1980 and 2014 for late complications 8-42 years after surgical treatment of aortic coarctation.

RESULTS

In 28 patients aneurysm formation after isthmic patch plasty was found. Two patients had aortobronchial fistula, 2 patients showed anastomosis disruption and 2 patients had graft stenosis. During operation hybrid solution was performed in 23 patients, isthmic aorto-aortic inlay graft interposition in 5 patients, aorto-aortic bypass in 2 patients, subclavio-aortic bypass in 2 patients, graft patch plasty in one patient and ilio-renal bypass in one patient. Complications included severe intraoperative bleeding in one patient and pneumothorax in one patient. No early or late mortality occurred.

CONCLUSIONS

The authors conclude that life long control is mandatory in order to detect late complications in patients who underwent operation of aortic coarctation in childhood.