Arteriovenous malformation of brain with stroke in Down syndrome: a case report
- 1Institute Of Medical Sciences, Pediatrics, 7FF, Kabir Colony, BHU, Varanasi 221005, India
- 2Nalanda Medical College, Pediatrics, 8 Rajendra Nagar, Patna, Bihar 800013, India
- 3Institute of Medical Sciences, Banaras Hindu University, Varanasi, 12 GF, Kabir Colony, BHU, Varanasi 221005, India
- Published 20 February 2009
Down syndrome is a common chromosomal aberration in children. A variety of associated malformations have been reported in the literature, including vascular malformations of pelvic organs. The vascular malformations of brain with Down syndrome have not been reported in the literature. Therefore, we report a child with Down syndrome, with associated arteriovenous malformation in the brain, who developed stroke and was treated successfully.
Down syndrome is the commonest chromosomal disorder in children There have been few case reports of Down syndrome being associated with vascular malformations in the pelvis,1 abdomen and spine,2–4 but arteriovenous malformation of the brain has not been reported to date in association with Down syndrome. We report herein a child with Down syndrome who developed stroke (hemiparesis) due to an arteriovenous malformation in the brain.
An 18-month-old female child was admitted with complaints of recurrent fever, cough and rapid breathing for 6 months. She was born as a full term by spontaneous vaginal delivery at home and had no history of perinatal asphyxia. Her development was globally delayed. The mother’s age was 23 years at the time of her birth, and she had one younger sibling who is normal. On examination, the patient was febrile (38.2°C) and had tachypnoea (resiratory rate: 57/min), tachycardia (128/min), chest retractions and generalised hypotonia. She had facial dysmorphism (hypertelorism, upward slanting of palpebral fissures, flat nasal bridge, epicanthal folds and protruding tongue), short broad hands with simian crease in both hands, suggestive of Down syndrome (fig 1). On auscultation of the chest, fine crepitations were heard bilaterally. In a cardiovascular examination, a pansystolic murmur was present, grade 4/6, best heard in the left fourth intercostal space in the parasternal area and radiating to the whole of the precordium, compatible with clinical diagnosis of ventricular septal defect. Other systemic examinations were unremarkable at admission. On day 6 of admission, she developed right-sided sudden-onset complete hemiparesis, which then remained static.
On investigation, haemoglobin was 11 g/dl, total leucocyte count 7350/mm3 with a differential of 64% neutrophils and 36% lymphocytes. Renal function tests and electrolytes were normal. Chest x rays showed cardiomegaly (CT index: 0.62) with bilateral infiltrates. Blood cultures (three samples: both aerobic and anaerobic) were sterile. Echocardiography revealed a moderate-size (6 mm) membranous ventricular septal defect with a shunt from the left ventricle to right ventricle and left ventricle to right atrium (fig 2). There were no features of infective endocarditis. The cytochemical studies done after fundus examination on day 7 and culture of cerebrospinal fluid examination were normal. The CT scan of cranium, which was done on day 6, was suggestive of an arteriovenous malformation of the left temporoparietal area, which was later confirmed on an MRI of the brain in the region of the cigulate gyri (fig 3). Karyotyping of the child and the parents was also performed. The child showed trisomy of chromosome 21 (fig 4), but the parents were normal.
With provisional diagnosis of Down syndrome with an arteriovenous (AV) canal defect and bronchopneumonia, the child was managed with oxygen inhalation in a propped up position, maintenance intravenous fluids, antibiotics (Ampicillin and Cefotaxime) and digoxin. Gradually, she became afebrile, respiratory distress settled, and feeding was started. Physiotherapy of the limbs was started, and the child was discharged after completing 2 weeks of intravenous antibiotics therapy on digoxin and iron supplementation. There was no improvement in weakness until discharge.
The child was then referred to the Department of Neurosurgery for steriotactic radiosurgical treatment (gamma knife) of arteriovenous malformation (AVM) and Department of Cardiothoracic Surgery for closure of the AV canal defect. After surgical ligation, the patient was discharged on day 7 of the postoperative period and showed improvement in power to grade III. In the follow-up at 3 months, the patient had grade I weakness and was advised to continue physiotherapy. The patient is doing well without any focal neurological deficit at 6 months but with global delayed developmental milestones and hypotonia.
AVMs are tangled anastomoses of blood vessels of varying calibre in which arteriovenous shunting occurs in a central nidus and from which enlarged veins drain.5 Vascular malformations of various sites have been described previously in association with Down syndrome,1–3 but we did not find any reports of hemiplegia due to arteriovenous malformation of brain in a patient with Down syndrome in literature. Abdominal venous malformations are probably the most frequent congenital vascular malformations in Down syndrome.2
Thirty per cent of the AVMs of the brain in paediatric patients are galenic AVMs presenting in newborns with cardiac failure, which is associated with highest mortality.5 An AVM of the brain may remain asymptomatic or may present with stroke, epilepsy, headache, focal neurological deficit and cognitive dysfunction. Other rare manifestations include pulsatile tinnitus, cranial nerve palsies, raised intracranial tension, trigeminal neuralgia and hemifacial spasm.6 Rarely, brain AVMs may cause focal symptoms and signs in the absence of prior or concomitant intracranial haemorrhage, as it occurred in the present case. While these deficits have traditionally been attributed to reduced perfusion pressure (steal) due to high flow in the feeding arteries of the brain AVM, the most likely cause in our patient,7 other causes of neurological deficit may be intracranial bleed or subarch.
The widespread availability and immediacy of CT pragmatically make it the first test in children. However, enhanced CT is a more sensitive investigation, because it may reveal the dilated vasculature of an AVM with a serpiginous pattern of contrast enhancement.8 The particular strengths of MRI lie in its evaluation of AVM nidus size9 and its anatomical relationships.
Children with AVMs should be treated aggressively because of the risk of future catastrophic haemorrhage. Surgical removal of an AVM is indicated if the operative risk is less than the risk determined by the natural history of the AVM. Steriotactic radiosurgical treatment (gamma knife) is a minimally invasive and effective strategy for surgical removal of an AVM.10
The outcome depends on the size and location of the malformation. Complete surgical removal almost certainly prevents recurrence, whereas incomplete removal and ligation of feeding vessels does not. Incomplete obliteration by embolisation also fails to provide protection from recurrent haemorrhage, even if follow-up angiography appears to show complete obliteration of the lesion.10
Congenital malformations are common in down syndrome.
AVMs of pelvic organs are reported in the literature.
AVMs of brain in the present case have not been reported to date in the literature.
Early recognition and surgical intervention of AVMs may be life-saving.
Competing interests: none.
Patient consent: Patient/guardian consent was obtained for publication