Venous Malformations and Blood Coagulation in Children.

INTRODUCTION: Venous malformations (VMs) are congenital low-flow lesions with a wide spectrum of clinical manifestations. An increasing number of studies link VMs to coagulation abnormalities, especially to elevated D-dimer and decreased fibrinogen. This condition, termed localized intravascular coagulopathy (LIC), may pose a risk for hemostatic complications. However, detailed data on the laboratory variables for coagulation and fibrinolytic activity in VM patients are limited. We addressed this question by systematically analyzing the coagulation parameters in pediatric VM patients. METHODS: We included 62 patients (median age 11.9 years) with detailed laboratory tests for coagulation and fibrinolytic activity at a clinically steady phase. We assessed clinical and imaging features of VMs and their correlations with coagulation and fibrinolysis variables using patient records and MRI. RESULTS: D-dimer was elevated in 39% and FXIII decreased in 20% of the patients, as a sign of LIC. Elevated D-dimer and decreased FXIII were associated with large size, deep location, and diffuse and multifocal VMs. FVIII was elevated in 17% of the patients and was associated with small VM size, superficial and confined location, discrete morphology, and less pain. Surprisingly, antithrombin was elevated in 55% of the patients but without associations with clinical or other laboratory variables. CONCLUSIONS: LIC was common in pediatric patients with VMs. Our results provide a basis for when evaluating the risks of hemostatic complications in children with VMs. Further research is warranted to explore the mechanisms behind coagulation disturbances and their relation to clinical complications.

Intra-articular venous malformation of the knee in children: magnetic resonance imaging findings and significance of synovial involvement.

BACKGROUND: Intra-articular venous malformations of the knee are an uncommon cause of unilateral knee pain in children. Timely diagnosis is important because lesions with intrasynovial involvement can lead to joint space hemorrhage and secondary cartilage damage. OBJECTIVE: To describe our tertiary center's experience of diagnostics and typical magnetic resonance imaging (MRI) findings. MATERIALS AND METHODS: A retrospective review of all patients ≤16 years of age managed for intra-articular venous malformations of the knee at our institution between 2002 and 2018. RESULTS: Of 14 patients (8 male), the mean age at presentation was 6 years (range: 0-14 years). The most common clinical findings were unilateral knee pain (93%), joint swelling (79%), quadriceps atrophy (50%) and a limited range of motion (29%). Cutaneous manifestations were present in four patients (29%). Contrast-enhanced MRI was available in all cases. After initial MRI, a vascular anomaly etiology had been identified in 11 cases (79%), and correctly reported as a venous malformation in 6 (55%). Three patients received entirely different diagnoses (arthritis, tumor or pigmented villonodular synovitis). Three of seven patients with intrasynovial lesions had established chondropathy at diagnosis. Two patients with lesions of the suprapatellar fat pad had intrasynovial involvement that was not visualised on MRI. CONCLUSION: Although MRI usually permits the diagnosis, clinical awareness of these lesions is important for optimal imaging, accurate interpretation and timely diagnosis. Involvement of the intrasynovial cavity carries a risk of hemarthrosis and progressive chondropathy that may be underestimated by MRI.

An interdisciplinary specialist team leads to improved diagnostics and treatment for paediatric patients with vascular anomalies.

AIM: Patients with vascular anomalies are often misdiagnosed, leading to delayed or improper treatment. The aim of this study was to evaluate the impact of an interdisciplinary team on the diagnosis and treatment of paediatric patients with vascular anomalies. METHODS: We reviewed the paediatric patients evaluated by our interdisciplinary team between 2002 and 2012, analysing the referral diagnosis, final diagnosis, patient age, sex, clinical history, laboratory tests, imaging studies and treatments. RESULTS: Of the 480 patients who were evaluated, 435 (90.6%) had a vascular anomaly: 30.7% of all patients had a tumour and 55.2% had a malformation. Haemangiomas comprised 93.2% of all tumours, while malformations included capillary (9.8%), lymphatic (30.1%), venous (36.8%), arteriovenous (3.8%) and combined slow-flow (7.9%) malformations. Tumours were initially diagnosed correctly in 89.2% of the patients, but only 38.0% of the malformations were diagnosed correctly. Improper treatment was given to 1.4%, due to incorrect diagnoses. CONCLUSION: This study showed that haemangiomas were likely to be diagnosed correctly, but other tumours and vascular malformations were likely to be misdiagnosed. Misdiagnosis seldom led to improper treatment, but probably led to delayed treatment in many cases. The interdisciplinary approach led to improved diagnostics and treatment.