[Brain abscess in patients with cyanotic heart defects]

As a result of hypoxia following right-to-left shunts, cerebral bacterial spreading and an altered blood-brain-barrier permeability, brain abscesses (BA) are typical complications in patients with cyanotic congenital heart disease. In 483 prospectively followed patients the incidence of BA was 0.45%/year. It was higher (0.57%/year) for patients with tetralogy of Fallot where the cumulative risk within the first two decades of life was 12.1 +/- 1.7%. The risk of BA complicating cyanotic heart disease is inconstant and continuously increasing up to approximately age 12 (instantaneous risk at that time: 1.75 +/- 0.12%), decreasing thereafter. With respect to etiology, infectious endocarditis, infections per continuitatem, bacterial meningitis, bacterial lung diseases with intrapulmonary shunts, and thromboembolic complications of systemic infections have to be differentiated. The stepwise diagnosis includes CCT to demonstrate the typical contrast enhancement and a lumbar puncture which shows granulocytic pleocytosis. If the cerebral spinal fluid fails to demonstrate the typical findings, cerebral angiography may be necessary to exclude a malignant vascularized neoplasma. In cases of doubt, stereotactic cerebral biopsy should be performed. Optimal antibiotic therapy after determining the minimal bactericidal concentration and combination of antibiotics is of utmost prognostic significance. Cranial computed tomography should be repeated after 6, 14, and 24 days. Infections resistant to antibiotics may necessitate local instillation of antibiotics.