Diagnosis and monitoring of central nervous system involvement in systemiclupus erythematosus: value of F-18 fluorodeoxyglucose PET

Objective-To investigate prospectively abnormalities of brain glucose utili sation in relation to major or minor neuropsychiatric symptoms in systemic lupus erythematosus (SLE). Methods-Positron emission tomography (PET) using F-18-labelled fluorodeoxyg lucose was performed in 28 patients with SLE. Patients were classified as h aving severe neuropsychiatric manifestations (seizures, focal neurological deficits, acute confusional states, mood disorders) (n=12), or mild neurops ychiatric manifestations (headache, reactive depression, cognitive dysfunct ion, anxiety disorders) (n=11) and five patients without signs of central n ervous system (CNS) involvement. Ten clinically and neurologically healthy volunteers served as controls. In 26 patients magnetic resonance imaging (M RI) was performed and autoantibodies against CNS tissue, ribosomal P protei n and cardiolipin were measured. In 14 patients follow up PET sans were per formed after a mean (SD) period of 11.6 (9.5) months. Results-PET scans showed hypometabolism in at least one brain region in all patients with severe or mild CNS symptoms (100%) as compared with patients without cerebral symptoms (40%) (p<0.0025). Parieto-occipital regions were most commonly affected (96%), followed by parietal regions (32%). In contr ast, MRI images were abnormal in only 11 of 22 patients (50%) with neuropsy chiatric symptoms and in one of four patients (25%) without symptoms. In 12 of 14 patients examined in follow up PET scans persistence, improvement or worsening of cerebral symptoms were associated with unchanged, decreased o r increased brain hypometabolism, respectively. No significant correlation was found between PET or MRI findings and autoantibody profiles. Conclusions-PET imaging represents a sensitive tool to detect manifest or s ubclinical CNS involvement in SLE and PET findings correlate well with the clinical course of disease.