Pain in Children and Adolescents With Low-Flow Vascular Malformation and Its Relation to Thrombosis.

BACKGROUND: Patients with vascular malformations (VMs) experience a wide spectrum of symptoms including pain, physical impairment, bleeding, thrombosis and psychosocial problems. The occurrence of pain in these patients might be caused by thrombosis or phleboliths (due to venous stasis), ischemia, or neuropathy. We aimed to assess the frequency of pain in patients with low-flow VM and to study its association with laboratory markers and radiological evidence of thrombosis. PATIENTS AND METHODS: A cross-sectional study that included 30 patients (12 female and 18 male) with low-flow VM. Medical records were reviewed for demographic data and details of VM. Assessment of pain was done by using the Face, Legs, Activity, Cry, Consolability (FLACC) scale and by the Wong-Baker FACES pain rating scale for patients 3 years or older. Markers of thrombosis including D-dimer level were measured. Results of radiologic investigations including Doppler ultrasonography and magnetic resonance imaging (MRI) were collected. RESULTS: The median age of patients was 51.4 months. Of 30 patients, 16 had VMs, 6 patients had lymphatic malformations and 8 had combined malformations. Eleven patients had thrombi or phlebolith by Doppler ultrasound or MRI. Pain was reported by 25 (83%) patients (acute pain in 11 and chronic pain in 14). D-dimer levels were highest in patients with acute pain (median level 1337 ng/mL) compared to those with chronic or no pain (p = 0.002). All 11 patients who had thrombi or phlebolith by Doppler ultrasound or MRI reported pain (6 with acute and 5 with chronic pain). CONCLUSION: Acute pain in patients with low-flow VMs with venous component is associated with high D-dimer and intralesional thrombosis by Doppler ultrasound.