PET findings in a brain abscess associated with a silent atrial septal defect

Brain abscesses are classical complications of congenital heart disease (CHD) in children and adolescents. This association is rarely observed in adults. We report a 46-year-old man presenting a fronto-parietal abscess associated with an asymptomatic atrial septal defect. Positron emission tomography (PET) study revealed high uptake of l-[ methyl- 11C]methionine ([ 11C]methionine) and 2-[ 18F]fluoro-2-deoxy- d-glucose (FDG) around the brain abscess. We suggest (1) to exclude a silent cardiac malformation in the presence of a cerebral abscess of unknown source occurring in adults; (2) to consider the diagnosis of brain abscess in cases of high uptake of [ 11C]methionine and FDG in relation to a brain lesion.