Objective: To verify whether features of CNS involvement can be detected in SLE patients without overt neuropsychiatric manifestations.

Methods: 114 SLE patients who had never received a diagnosis of neuropsychiatric lupus (never NPSLE) were studied and compared to 65 SLE patients with known neuropsychiatric involvement (NPSLE). The study relied on evaluation of neurocognitive functions by means of a battery of neuropsychological tests, on psychiatric and neuropsychological assessments and on neuroimaging studies (computed tomography, magnetic resonance, single photon emission computed tomography (SPECT)).

Results: Clinical features, including disease duration/activity and pharmacological therapy, of never-NPSLE and NPSLE patients were similar. Short-term and long-term memory, visuo-spatial and verbal information processing were similarly compromised in never-NPSLE and in NPSLE patients; only attention was significantly more compromised in NPSLE patients. Psychiatric morbidity was higher than expected in never-NPSLE patients, although less than in the control neuropsychiatric group. Ischemic lesions, multiple small high intensity lesions and cortical atrophy, detected by CT and MR scans, as well as abnormal SPECT were also frequently detected in never NPSLE patients. Interestingly, left parietal and occipital area hypoperfusion by SPECT was significantly more frequent in the patients with impaired visuo-spatial intelligence and short-term memory.

Conclusions: Most abnormalities detected by available diagnostic tools and characteristics of neuropsychiatric SLE are also present in non-symptomatic patients. They may derive from an unexpected widespread involvement of the CNS and are not per se sufficient, in the absence of clinical manifestations, for a diagnosis of neuropsychiatric SLE.