Reversible Amygdala and Parahippocampal Lesions of Brain 18Fluorodeoxy Glucose-Positron Emission Tomography in Neuropsychiatric Systemic Lupus Erythematosus

Abstract

A diversity of neurologic and psychiatric symptoms in systemic lupus erythematosus (SLE) are reported to occur in 14− 75% of patients either prior to the diagnosis or during the course of their illness.1 The involvement of the central nervous system (CNS) in SLE is a serious but potentially treatable illness, yet SLE still presents a very difficult diagnostic challenge. Neuropsychiatric involvement in SLE (NPSLE) appears to be caused by complex pathologic processes attributed to autoantibody mediated neuronal or vascular injury, intrathecal production of inflammatory cytokines, and disruption of the blood-brainbarrier (BBB).2 The frequency of NPSLE varies widely, depending on the type of manifestations and the method used for evaluation. The role of the different neuroimaging modalities in the diagnosis and evaluation of disease activities of NPSLE is still very controversial. Magnetic resonance imaging (MRI) remains the gold standard for the non-invasive assessment of NPSLE but there are limitations with its sensitivity and specificity. Single photon emission computed tomography (SPECT) or positron emission tomography (PET) have been found to be useful for early identification of blood-flow or metabolic abnormalities of NPSLE, but they lack spatial resolution. The quantification of change is straightforward.3,4 In this paper we report about brain PET findings in a young woman with NPSLE who first presented with amnesia and anosmia as neurological symptoms.