Brain Abscess in Children with Congenital Heart Disease

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“…A number of different theories have been put forward to explain why congenital heart disease is so closely associated with brain abscesses. Some authors postulate that due to the rightleft shunt, venous blood passes into the arterial system without being filtered through the pulmonary circulation, where bacteria are intercepted by phagocytes [13,14,15,16,17]. It is also thought that the brain itself may be predisposed to offer a focus of infection as a result of halomalacia encep secondary to embolism or polycythemia.…”

“…It is also thought that the brain itself may be predisposed to offer a focus of infection as a result of halomalacia encep secondary to embolism or polycythemia. Germs can then be seeded in this infarcted area, forming a brain abscess [13,17]. Berthrong and Sabiston [l] stressed the importance of polycythemia in the production of intravascular thrombosis leading to infarction.…”

Gemella morbillorum Cryptogenic Brain Abscess: A Case Report and Literature Review

“…As further investigations using CT angiography of the aorta and coronaries revealed contrast extravasation from the superior vena cava to the right superior pulmonary vein, suggestive of a right-to-left shunt, as well as a large sinus venosus atrial septal defect, revealed on trans-esophageal echocardiography, with evidence of intra-cardiac shunting. Right-to-left shunting as seen in various cardiovascular anomalies such as an atrial septal defect (ASD), patent foramen ovale (PFO), or anomalous pulmonary venous connection (partial or complete) may allow the passage of bacteria unhindered, avoiding the filtration mechanisms of the pulmonary circulation resulting in passage of a larger bacterial inoculum into the systemic circulation and the cerebral circulation resulting in abscess formation [13].…”

Abscesso cerebral associado à cardiopatia congênita cianótica: Considerações sobre 17 casos

“…Alguns autores referem que a principal causa é a comunicação direita-esquerda apresentada nesses pacientes. Com isso, o sangue venoso mistura-se com o sangue arterial antes de passar pela circulação pulmonar, deixando assim de ser filtrado, onde as bactérias são interceptadas por fagócitos, permitindo a passagem de microrganismos para a circulação cerebral 7,26,35,40,58,61 . Nesses pacientes, o cérebro apre-senta condições predisponentes, como áreas de baixa perfusão por causa da hipoxemia severa e acidose metabólica associada ao aumento da viscosidade do sangue resultante da policitemia compensatória, a qual, junto com a baixa saturação de oxigênio, prepara um foco receptivo para a infecção 18,35,61 .…”

“…Com o shunt direita-esquerda existente nesses pacientes, o sangue venoso passa para o sistema arterial, não havendo filtração pela circulação pulmonar, onde as bactérias são fagocitadas 7,18,26,40,58 . Tais pacientes apresentam também uma policitemia compensatória e hipóxia cerebral que são fatores predis-ponentes para a instalação de um foco infeccioso.…”