Neuropsychiatric systemic lupus erythematosus (NPSLE)

Clinical History

A 67-year-old female patient with a known history of systemic lupus erythematosus (SLE) presented with a 6-month history of headaches and 3-month history of confusion. Of note, the patient also had a history of gastrointestinal stromal tumour (GIST) and recently detected pulmonary nodules on CT.

Imaging Findings

T2 and FLAIR-weighted sequences demonstrated cortical and subcortical hyperintensities within the right inferior parietal lobule, left inferior temporal gyrus, left cingulate gyrus and left caudate head. Following gadolinium administration there was mild patchy enhancement in these regions, but no restricted diffusion. Multiple periventricular and deep white matter hyperintensities were best explained by moderate microangiopathic disease. There was mild global cortical atrophy.

The patient was re-imaged within a 4-month interval, following treatment with 6 cycles of IV cyclophosphamide. This showed near complete resolution of the previously demonstrated abnormalities, with only a small persisting FLAIR hyperintensity in the right inferior parietal lobule, but no enhancement.

Discussion

Neuropsychiatric manifestations have been reported in up to 75% of patients with SLE [1], although the true prevalence is not known. The pathophysiology of NPSLE remains unclear but is likely to be multifactorial, the main pathogenic mechanisms thought to involve vascular abnormalities, autoantibodies and inflammatory mediators [2].

NPSLE is characterised by a wide range of clinical manifestations and remains a diagnostic challenge for clinicians. The most commonly presenting syndromes requiring neuroimaging include headache, cerebrovascular disease, epilepsy and cognitive dysfunction [3]. MRI is the gold standard neuroimaging technique for studying the brain and can help identify structural abnormalities related to NPSLE, although the findings are relatively non-specific.

Around 50% of NPSLE patients who undergo MRI imaging of the brain have normal appearances [4]. Of those with abnormal findings, these can be split into either vascular or inflammatory type lesions [3].

Most vascular lesions are manifestations of small vessel disease, which include multiple small white matter hyperintensities, cortical atrophy, microhaemorrhage and lacunar infarcts. Large territorial infarcts are seen less frequently in large vessel disease.

Inflammatory type lesions are a comparatively uncommon manifestation. A multicentre retrospective analysis of NPSLE patients who underwent MRI of the brain identified these
in only 7% (4). These are characterised by medium to large, ill-defined T2 or FLAIR hyperintensities involving either the grey or white matter and not conforming to vascular territories, sometimes with mass effect. 5 out of the 7 patients (71%) with inflammatory lesions showed contrast-enhancement. Restricted diffusion was seen in 1 patient (14%).

NPSLE is associated with high morbidity and mortality. Aggressive immunosuppressive therapy, in particular IV cyclophosphamide, has yeilded good results [5, 6]. Although a rare manifestation, the lesions demonstrated in this case were likely to represent reversible inflammatory lesions, thus their timely recognition was required in order to commence treatment. Background changes of microangiopathic disease and global cortical atrophy may also have been vascular manifestations of the disease.

Prompt referral for MRI is therefore required when there is suspicion of NPSLE. Standard MRI sequences will identify chronic features of small or large vessel disease and possibly inflammatory lesions if present. Additional helpful sequences include diffusion weighted imaging to look for acute infarcts, gradient echo or susceptibility weighted imaging to look for microhaemorrhage, and contrast enhanced images for inflammatory lesions. Advanced MRI techniques are not currently widely available in standard clinical care, but show promise for potential future roles in earlier detection of NPSLE.

Written informed patient consent for publication has been obtained.

Differential Diagnosis List

Final Diagnosis

NPSLE with reversible inflammatory lesions.

URL:	https://www.eurorad.org/case/15747
DOI:	10.1594/EURORAD/CASE.15747
ISSN:	1563-4086