Optimizing clinical monitoring of central nervous system involvement in SLE

Abstract

Central Nervous System (CNS) involvement is a frequent SLE manifestation occurring in 15–75% of patients. However, diagnosis of CNS involvement is a difficult task and requires a careful clinical and laboratory assessment along with instrumental evaluation. In recent years major advances in neuroimaging techniques allowed a great improvement in our understanding of SLE pathogenesis. Anyway, since no single imaging technique covers all brain pathology and both inflammation and neurodegeneration contribute to SLE pathogenesis, it is very important to use a multimodality approach coupling a morphological with a functional imaging modality. In this setting, to date, conventional magnetic resonance imaging and single photon emission computed tomography are the most largely available and accessible techniques. Modern techniques such as perfusion weighted imaging, diffusion weighted imaging, magnetization transfer imaging and magnetic resonance spectroscopy provide useful information to assess brain tissue damage however, their clinical relevance in individual patients needs further evidence.

In this review we would like to summarize what have we learned in the last few years about neuroimaging in NPSLE, what have been major advances in neuroimaging techniques and, finally, we would like to give some suggestions about what should be done in daily clinical practice to approach SLE patients with NP symptoms.

Introduction

Central Nervous System (CNS) involvement is a frequent SLE manifestation occurring in 15–75% of patients depending on population studied and inclusion criteria [1]. Normative classification criteria for NPSLE are now available representing an important tool in clinical practice [2]. However, diagnosis of CNS involvement is a difficult task and requires a careful clinical and laboratory assessment along with instrumental evaluation to rule out other causes of neuropsychiatric symptoms. About neuroimaging, it must be remembered that no single technique has diagnostic specificity for NPSLE nor accounts for all brain pathology underlying NP clinical syndromes. Furthermore, in SLE patients, clinical symptoms may occur without instrumental abnormalities and instrumental abnormalities may occur in asymptomatic patients. So far, there aren't guidelines suggesting the best neuroimaging approach to NPSLE and coupling a morphological technique with a functional technique seems actually the most valuable solution. While conventional MRI (cMRI) remains the preferred technique for the morphological evaluation of CNS in SLE patients, in the last decade major advances have been done in the assessment of perfusional, metabolic and microstructural brain alterations not detected by cMRI.

In this review we would like to summarize what have we learned in the last few years about neuroimaging in NPSLE and what have been major advances in neuroimaging techniques; finally, we also would like to give some suggestions about what should be done in daily clinical practice to approach SLE patients with NP symptoms with particular attention to the diffuse presentation of NPSLE.