Impaired social cognition and fine dexterity in patients with Cowden syndrome associated with germline PTEN variants.

PURPOSE: Cowden syndrome (CS) is an autosomal dominant disease related to germline PTEN variants and is characterised by multiple hamartomas, increased risk of cancers and frequent brain alteration. Since the behaviour of patients with CS sometimes appears to be inappropriate, we analysed their neuropsychological functioning. METHODS: This monocentric study was conducted between July 2018 and February 2020. A standardised neuropsychological assessment, including an evaluation of social cognition, executive functions, language and dexterity, as well as a cerebral MRI were systematically proposed to all patients with CS. Moreover, PTEN variants were identified. RESULTS: Fifteen patients from 13 families were included, with six non-sense (40%), three missense (20%), five frameshift (33.3%) and one splice site (6.6%) variant types. Twelve patients (80%) had altered social cognition: 10 patients had an abnormal modified Faux-Pas score and 5 had Ekman's facial emotions recognition impairment. Nearly all patients (93%) had impaired dexterity. Cerebral MRI showed various cerebellar anomalies in seven patients (46.7%). CONCLUSION: Altered social cognition and impaired fine dexterity are frequently associated with CS. Further studies are needed to confirm these results and to determine whether dexterity impairment is due to the effect of germline PTEN variants in the cerebellum.

The Diagnostic Value of a Short Memory Test: The TNI-93.

BACKGROUND: The TNI-93 is a quick memory test designed for all patients regardless of their education level. A significant proportion of patients with Alzheimer's disease (AD) are illiterate or poorly educated, and only a few memory tests are adapted for these patients. OBJECTIVE: In this study we aimed at assessing the diagnostic value of the TNI-93 for diagnosis of patients with biologically confirmed amyloid status. METHODS: We included all patients who had an analysis of AD cerebrospinal fluid biomarkers, a neuropsychological assessment including a TNI-93 and an anatomical brain imaging at Avicenne Hospital between January 2009 and November 2019. We compared the TNI-93 scores in patients with amyloid abnormalities (A+) and patients without amyloid abnormalities (A-) according to the AT(N) diagnostic criteria. RESULTS: 108 patients were included (mean age: 66.9±8.5 years old, mean education level: 8.9±5.2 years). Patients from the A + group (N= 80) were significantly more impaired than patients from the A- group (N= 28) on immediate recall (A+: 5.9±2.8; A-: 7.4±2.6; p = 0.001), free recall (A+: 3.5±2.7; A-: 5.9±2.8; p ≤ 0.001), total recall (A+: 5.7±3.5; A-:7.8±2.8; p ≤ 0.001), and on number of intrusions during the recall phase (A+: 1±1.8; A-: 0.1±0.3; p = 0.002). ROC curves revealed that the best scores to discriminate A + from A- patients were immediate recall (Area under curve (AUC): 0.70), number of encoding trials (AUC: 0.73), free recall (AUC: 0.74), and total recall (AUC: 0.74). CONCLUSION: The TNI-93's immediate, free, and total recalls are valuable tools for the 39 diagnosis of AD.