title: [A complicated case of Nocardia brain abscess for differential diagnosis].
abstract: BACKGROUND
  Nocardia brain abscess is rare and has uncertain clinical features. Radiological differential diagnosis based on the metabolic feature of Nocardia is discussed.
  
  
  METHODS
  A 73-year-old man presented with a history of otitis media and was treated with antibiotics for 2 weeks. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated an irregular ring-enhancement mass in the left cerebellar hemisphere. This lesion presented as a homogeneous high-intensity area in diffusion-weighted MRI. We also found decreased N-acetyl-aspartate (NAA) peak and increased choline and lipid peaks in proton MR spectroscopy (1H-MRS). We performed an aspiration. Nocardia asiatica in the mass lesion was found by genetic analysis. The patient was treated with a sulfamethoxazole/trimethoprim (ST) mixture and minocycline (MINO) intravenously for 6 months. There has been no recurrence for 2 years.
  
  
  CONCLUSIONS
  To our knowledge, this case is the first case of Nocardia asiatica brain abscess in Japan. We considered these MRS findings to be compatible with Nocardia brain abscess as mainly observed in aerobic metabolism. But we also detected a lactate peak in the abscess. Further research is required.
authors.affiliation: Department of Neurosurgery, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki-shi, Kanagawa 216-8511, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Wakui
authors.forename: Hidemichi
authors.initials: H
authors.lastname: Ito
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Ikeda
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Yu
authors.initials: Y
authors.lastname: Furuya
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Tanaka
authors.forename: Takuo
authors.initials: T
authors.lastname: Hashimoto
mesh_terms: D000368:Aged; D001922:Brain Abscess / Q000175:diagnosis*; D001932:Brain Neoplasms / Q000175:diagnosis; D003937:Diagnosis, Differential; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009617:Nocardia Infections / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed