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Introduction: Hereditary transthyretin amyloidosis polyneuropathy (ATTRv‐PN) presymptomatic carriers often show preclinical abnormalities at small fiber‐related diagnostic tests. However, no validated biomarker is currently available to use for presymptomatic carriers' follow‐up, thus helping therapeutic decision making. Our study aimed at assessing nerve conduction study (NCS), quantitative sensory testing (QST), and skin biopsy parameters in a large cohort of late‐onset ATTRv presymptomatic carriers and to evaluate whether they correlated with predicted age of disease onset (PADO). Methods: Late‐onset ATTRv presymptomatic carriers were consecutively enrolled and underwent NCS, QST, and skin biopsy with intraepidermal nerve fiber density (IENFD) evaluation from a distal and a proximal site. Douleur Neuropathique‐4 (DN4) and Small Fiber Neuropathy‐Symptoms Inventory (SFN‐SIQ) were used to assess painful and small fiber neuropathy‐related symptoms. PADO and time‐to‐PADO (delta‐PADO) were estimated for each carrier, and correlations with diagnostic test measures were analyzed. Results: Forty presymptomatic ATTRv subjects were enrolled. Twenty carriers (50%) had distal IENFD reduction, with a non‐length‐dependent distribution in 73% of cases. Eleven subjects (27.5%) had cold and/or warm detection threshold (CDT and/or WDT) abnormalities at QST. Delta‐PADO positively correlated with sural sensory nerve action potential (SNAP) amplitude (r =.416, p =.004), and z‐values of QST parameters like CDT (r =.314, p =.028), WDT (r = −.294, p =.034), and mechanical detection threshold (MDT; r = −.382, p =.012). Simple linear regression models showed a linear relation between delta‐PADO and sural SAP, CDT, and MDT. Conclusions: Our findings confirm that IENFD reduction and QST abnormalities may occur early in ATTRv presymptomatic carriers, often with a non‐length‐dependent pattern. However, only sural SAP amplitude and QST parameters correlated with delta‐PADO, suggesting that serial combined QST and NCS evaluation could be useful in ATTRv presymptomatic carriers' follow‐up. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the presence of neuromuscular involvement in patients in vegetative and minimally conscious states (VS, MCS) following acute brain injury. Twenty-two patients (11 in VS, 11 in MCS) admitted to a rehabilitation department underwent nerve conduction, electromyography (EMG) for spontaneous activity and direct muscle stimulation (DMS). Twenty (90.9%) showed abnormal nerve conduction studies, 19 (86.4%) had spontaneous EMG activity, and 7 (31.8%) had abnormal DMS. The time spent in the intensive care unit correlated significantly with the amplitude of the compound muscle action potential of the ulnar nerve and with the amplitude of the sensory nerve action potential of the sural nerve (p < 0.05). No significant differences were found between patients in VS and MCS. Neurophysiological data indicative of neuromuscular involvement are common in patients in VS and MCS. This study underlines the need to implement strategies to prevent and to treat neuromuscular complications in patients in VS and MCS. [ABSTRACT FROM AUTHOR]