Evaluation of a Patient With a Brain Abscess Caused by Nocardia Asteroides Infection With Ga-67 and Tc-99m HMPAO Leukocytes

A female patient with nocardia interstitial pneumonia developed an abscess in the left parietal lobe. Nocardia asteroides was isolated from the brain abscess at craniotomy. Fifteen days later, a brain MRI showed a mass at the craniotomy site. Recurrent abscess was suspected and Ga-67 brain SPECT showed increased uptake in the left parietal area. Five days later, Tc-99m HMPAO leukocyte brain SPECT showed only a weak uptake in the same region. The different results of the two radionuclides are difficult to explain and could be related to a complex mechanism of uptake, bacterial resistance, and specific therapy.