Differential diagnosis of CNS lesions in AIDS patients by FDG-PET

J Comput Assist Tomogr. Jul-Aug 1995;19(4):532-6. doi: 10.1097/00004728-199507000-00004.


Objective: The aim of this study was to evaluate the potential of FDG-PET in the differential diagnosis of CNS lesions in patients with AIDS, particularly to differentiate between toxoplasmosis and lymphoma.

Materials and methods: We examined 11 AIDS patients, 6 with toxoplasmosis, 1 with a tuberculoma, and 4 with a primary CNS lymphoma. The FDG uptake within the lesion was compared with the uptake in a contralateral brain area [standardized uptake value (SUV)].

Results: In all subjects with cerebral infections (toxoplasmosis, tuberculoma), the SUV ratio was significantly (p < 0.05) lower than the SUV ratio in patients with lymphoma (range of 0.3-0.7 vs. 1.7-3.1) with no overlap of the uptake values.

Conclusion: In conclusion, FDG-PET may help to characterize these lesions metabolically and play an important role in the clinical management of AIDS patients with CNS involvement.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS-Related Opportunistic Infections / diagnostic imaging*
  • Adult
  • Brain / diagnostic imaging
  • Central Nervous System Neoplasms / diagnostic imaging*
  • Deoxyglucose / analogs & derivatives*
  • Diagnosis, Differential
  • Evaluation Studies as Topic
  • Female
  • Fluorine Radioisotopes*
  • Fluorodeoxyglucose F18
  • Follow-Up Studies
  • Humans
  • Lymphoma, AIDS-Related / diagnostic imaging*
  • Male
  • Time Factors
  • Tomography, Emission-Computed
  • Toxoplasmosis, Cerebral / diagnostic imaging*
  • Tuberculoma, Intracranial / diagnostic imaging*


  • Fluorine Radioisotopes
  • Fluorodeoxyglucose F18
  • Deoxyglucose