To the Editor:
Neuropsychiatric manifestations of systemic lupus erythematosus (NPSLE) are responsible for high rates of morbidity and mortality. Zirkzee, et al1 emphasize the importance of ascertaining the different NPSLE phenotypes, which could be helpful in making potential therapeutic decisions. However, it is evident that there were patients who had both profiles described by the authors, that is, inflammatory and ischemic. Because of such overlapping of severe NPSLE manifestations, we consider that physicians must keep in mind starting therapy for both patterns while waiting to define the pathogenesis of the neurological expression. It is evident that high disease activity represents one of the most important risk factors for developing NPSLE, as obtained using the Systemic Lupus Erythematosus Disease Activity Index, and it includes NPSLE manifestations as the main factor. We consider that the study by Zirkzee, et al could have incorporated other biomarkers suggested by some algorithms, and lumbar puncture has been suggested as a diagnostic approach2 that could help in excluding other involved factors besides SLE activity, such as infections. Recently, it has been reported that positron emission tomography scanning is more sensitive than magnetic resonance imaging (MRI)3; although Zirkzee, et al reported 100% sensitivity of MRI, this sensitivity is lower when there is no focal neurological deficit related to NPSLE, as described in some cases of small-vessel central nervous system angiitis, as well as other manifestations4. Moreover, conventional MRI may present limitations in interpretation because lesions may be acute and/or chronic5, and we recognize that MRI studies should include special techniques (e.g., diffusion and metabolites).