Epileptic Prodromal Alzheimer's Disease, a Retrospective Study of 13 New Cases: Expanding the Spectrum of Alzheimer's Disease to an Epileptic Variant?

BACKGROUND: Aside from rare case reports, only one study, with 12 patients, has addressed the phenotypic presentation of epilepsy in clinically defined amnestic mild cognitive impairment (aMCI, presumed to correspond to the AD prodromal stage): the authors highlighted a pharmacosensitive non-convulsive partial epileptic syndrome most probably related to the temporal or temporo-frontal cortices. OBJECTIVE: The objective of this study was to verify the existence and the syndromic features of epileptic prodromal AD in a tertiary Memory Clinic. METHODS: We conducted a retrospective, single-center study of the electro-radio-clinical features of 13 cases of epileptic prodromal AD patients (3.1% of a cohort of MCI, n = 430 subjects), selected on both clinical criteria and CSF biomarkers. RESULTS: In our patients, a pharmacosensitive temporal lobe epilepsy syndrome, inaugurating prodromal AD, started at a mean age of 63 years (±12.8 years) and preceded MCI diagnosis by 4 to 7 years. At the stage of aMCI, median MMSE score was 26 and imaging showed mild hippocampal atrophy. After almost one year under treatment, cognitive complaints were not relieved but the MMSE score remained stable at 26 for 11 patients (2 patients were excluded from analysis because of the onset of aphasic or neurovisual symptoms altering MMSE scoring). CONCLUSION: Our data, in conjunction with those of the 12 previously described subjects, suggest the existence of a currently unrecognized inaugural epilepsy syndrome of sporadic AD. Such a syndrome could be called the epileptic variant of AD because seizures are its sole feature for more than 2.5 years.

Left temporal lobe epilepsy revealing left posterior cortical atrophy due to Alzheimer's disease.

Seizures can be an early symptom of Alzheimer's disease (AD) and can precede cognitive decline. Early epilepsy in AD can mimic transient epileptic amnesic syndrome (TEAS) or epileptic amnesic syndrome. We report the case of a patient who started a cerebrospinal fluid (CSF)-proven AD with partial seizures and TEAS that secondarily became a cortical posterior atrophy syndrome. CSF biomarkers showed a high amyloid production, amyloidopathy, and high level of total tau and p-Tau. This observation adds data to the complex AD-early epilepsy interactions and illustrates that atypical AD can cause a TEAS. Possible red flags for an underlying neurodegenerative process in TEAS are discussed.

Cognitive Dysfunction and Dementia in Primary Sjögren's Syndrome.

Background. Primary Sjögren's syndrome (PSS) is a frequent systemic autoimmune disease. In this study, we aimed to explore the cognitive impairment and the correlations with brain MRI. Methods. Twenty-five patients (mean age 55 ± 11.8 years, 21 females) with PSS were prospectively selected and tested with a French translation of the Brief Repeatable Battery for Neuropsychological Examination. The results were compared with the scores for 25 matched patients with multiple sclerosis (MS) and 25 controls. Brain lesions were assessed by brain MRI using the Wahlund classification. Results. Fifteen of the 25 PSS patients (60%) presented with cognitive disorders versus 19/25 MS patients (76%). Five patients had dementia in the PSS group. Speed of information processing, attention, immediate and long-term memory, and executive functions were frequently impaired. The mean duration of cognitive complaints was 5.6 ± 6.1 years, and the mean duration of PSS was 15.8 ± 14.0 years. A trend towards a correlation was found between the severity of cognitive impairment and the degree of white matter lesions (WML) (P = 0.03, rho = 0.43). Conclusion. Cognitive impairment-mild or dementia-exists in patients with PSS. Further MRI studies are needed to better understand the precise neural basis of cognitive impairment in PSS patients.

White matter atrophy and cognitive dysfunctions in neuromyelitis optica.

Neuromyelitis optica (NMO) is an inflammatory disease of central nervous system characterized by optic neuritis and longitudinally extensive acute transverse myelitis. NMO patients have cognitive dysfunctions but other clinical symptoms of brain origin are rare. In the present study, we aimed to investigate cognitive functions and brain volume in NMO. The study population consisted of 28 patients with NMO and 28 healthy control subjects matched for age, sex and educational level. We applied a French translation of the Brief Repeatable Battery (BRB-N) to the NMO patients. Using SIENAx for global brain volume (Grey Matter, GM; White Matter, WM; and whole brain) and VBM for focal brain volume (GM and WM), NMO patients and controls were compared. Voxel-level correlations between diminished brain concentration and cognitive performance for each tests were performed. Focal and global brain volume of NMO patients with and without cognitive impairment were also compared. Fifteen NMO patients (54%) had cognitive impairment with memory, executive function, attention and speed of information processing deficits. Global and focal brain atrophy of WM but not Grey Matter (GM) was found in the NMO patients group. The focal WM atrophy included the optic chiasm, pons, cerebellum, the corpus callosum and parts of the frontal, temporal and parietal lobes, including superior longitudinal fascicle. Visual memory, verbal memory, speed of information processing, short-term memory and executive functions were correlated to focal WM volumes. The comparison of patients with, to patients without cognitive impairment showed a clear decrease of global and focal WM, including brainstem, corticospinal tracts, corpus callosum but also superior and inferior longitudinal fascicles. Cognitive impairment in NMO patients is correlated to the decreased of global and focal WM volume of the brain. Further studies are needed to better understand the precise origin of cognitive impairment in NMO patients, particularly in the WM.