Brain abscesses associated with pulmonary arteriovenous malformations

We present three patients with brain abscesses who also had pulmonary arter iovenous malformations (AVMs). All patients had hereditary haemorrhagic tel angiectasia (Osler's Disease). It is probable that the lung AVMs contribute d to the development of the brain abscesses by allowing bacteria easier acc ess to the systemic circulation through a right to left pulmonary vascular shunt, bypassing the filtering action of the pulmonary capillaries. In addi tion, one patient required a period of postoperative ventilation using PEEP , which may have exacerbated the shunt through the lung AVM and led to diff iculty in weaning her from the ventilator.