Sensory neuronopathy is a specific and disabling neurological manifestation of autoimmune hepatitis.

BACKGROUND AND PURPOSE: Neurological manifestations have been identified in the context of autoimmune hepatitis (AIH). Previous case reports highlighted the association between AIH and sensory neuronopathy (SN). Despite that, little is known about the frequency of AIH-related SN and its clinical/neurophysiological profile. Moreover, it is not clear whether SN is an AIH-specific manifestation or related to chronic liver damage. METHODS: Seventy consecutive AIH patients were enrolled and their characteristics were compared with 52 consecutive patients with chronic active hepatitis B. All subjects underwent clinical and neurophysiological evaluation. Further comparisons were performed between AIH SN and AIH non-SN patients. RESULTS: Mean ages and male:female proportions in the AIH and chronic active hepatitis B groups were 42.2 ± 16.3/51.7 ± 13.6 years and 14:56/29:23, respectively. The frequencies of carpal tunnel syndrome, radiculopathy and polyneuropathy were similar between groups. In contrast, SN was identified only in AIH patients (5/70 vs. 0/52, P = 0.04); the overall prevalence of AIH-related SN was 7% with an average profile of a woman in her 40s with asymmetric onset of sensory deficits that chronically evolved to disabling proprioceptive ataxia associated with marked dysautonomia. Neurological disability and hepatocellular damage did not follow in parallel. Anti-fibroblast growth factor receptor type 3 antibodies were found in 3/5 (60%) of the patients with AIH-related SN. Clinical or demographic predictors of SN in the context of AIH could not be identified. CONCLUSION: Sensory neuronopathy, but not other peripheral nervous system diseases, is a specific AIH neurological manifestation. It is often disabling and, in contrast to hepatocellular injury, does not respond to immunosuppression.

Autonomic dysfunction in hereditary spastic paraplegia type 4.

BACKGROUND AND PURPOSE: SPAST mutations are the most common cause of hereditary spastic paraplegia (SPG4-HSP), which is characterized by progressive lower limb weakness, spasticity and hyperreflexia. There are few studies about non-motor manifestations in this disease and none about autonomic involvement. Therefore, the aim was to determine the frequency and pattern of autonomic complaints in patients with SPG4-HSP, as well as to determine the clinical relevance and the possible factors associated with these manifestations. METHODS: Thirty-four molecularly confirmed SPG4 patients were recruited in a multicenter cross-sectional study, of whom 26 underwent detailed neurophysiological testing (heart rate variability, sympathetic skin response and the Quantitative Sudomotor Axonal Reflex Test). The Scales for Outcomes in Parkinson's Disease - Autonomic Questionnaire (SCOPA-AUT) was applied to quantify the severity of autonomic symptoms. Results were compared with 44 age- and gender-matched healthy controls using non-parametric tests. P values <0.05 were considered significant. RESULTS: In the SPG4-HSP group, there were 18 men with a mean age of 47.7 ± 12.6 years. SCOPA-AUT scores were similar between patients and controls (P = 0.238). Only the urinary domain subscore was significantly higher amongst patients (4 vs. 2.5, P = 0.05). Absent sympathetic skin response in the hands and feet was more frequent amongst patients (20% vs. 0%, P < 0.001, and 64% vs. 0%, P = 0.006, respectively). Quantitative Sudomotor Axonal Reflex Test responses were also smaller throughout all recording regions in the SPG4-HSP group. CONCLUSION: Our results indicate that SPG4-HSP patients have sudomotor dysfunction caused by damaged small post-ganglionic cholinergic fibers. Damage in SPG4-HSP extends to the peripheral nervous system.

Developmental and neurodegenerative damage in Friedreich's ataxia.

BACKGROUND AND PURPOSE: Friedreich's ataxia (FRDA) is the most common autosomal-recessive ataxia worldwide. It is characterized by early onset, sensory abnormalities and slowly progressive ataxia. All magnetic resonance imaging (MRI)-based studies have focused on the evaluation of adult patients. Therefore, we designed a cross-sectional multimodal MRI-based study to investigate the anatomical substrates involved in the early stages of FRDA. METHODS: We enrolled 37 patients (12 children) and 38 controls. All subjects underwent MRI in a 3T device to assess gray and white matter. We used measures from FreeSurfer and CERES to evaluate the cerebral and cerebellar cortices. The T1 multiatlas assessed deep gray matter. The diffusion tensor imaging multiatlas was used to investigate microstructural abnormalities in brain white matter and SpineSeg was used to assess the cervical spinal cord. All analyses were corrected for multiple comparisons. RESULTS: Comparison with age-matched controls showed that pediatric patients have spinal cord, inferior cerebellar peduncle and red nucleus damage. In contrast, adult patients showed more widespread white matter damage than pediatric patients. With regard to gray matter, we found cortical thinning at the left central sulcus and volumetric reduction in the thalami and hippocampi only in adult patients. Finally, values of fractional anisotropy in adult patients and radial diffusivity in pediatric patients from the inferior cerebellar peduncle correlated with disease duration and ataxia severity, respectively. CONCLUSIONS: Structural damage in FRDA begins in the spinal cord and inferior cerebellar peduncle as well as the red nucleus, and progresses to cerebral areas in adulthood. These results shed some light on the early stages of FRDA and highlight potential neuroimaging markers for therapeutic trials.