Are electrophysiological features related to disability in patients with anti-MAG neuropathy?

OBJECTIVES: To explore clinical-neurophysiological correlations in anti-myelin-associated glycoprotein (anti-MAG) neuropathy. METHODS: Clinical and electrophysiological data of 42 patients with anti-MAG neuropathy were retrospectively analysed. Disability was evaluated using the Overall Neuropathy Limitation Scale (ONLS), motor impairment through MRC sum score and sensory deficiency through INCAT sensory score. Compound motor action potential (CMAP) sum score was calculated adding the distal CMAP amplitude of the median, ulnar, tibial and fibular nerves of both sides. RESULTS: In multivariate analysis, motor impairment was associated with CMAP sum score (r=0.35, P=0.047) and distal motor latency in the median nerves (r=-0.45 P=0.012), sensory deficiency was related to motor conduction velocity in the median nerve (r=-0.65. P=0.02). Disability was correlated with CMAP sum score (r=-0.37, P=0.022). CONCLUSION: Electrophysiological features are associated with clinical involvement in anti-MAG neuropathy. Reduction of CMAP amplitudes reflects distal motor latency delay and is mainly due to axonal loss. Since it is related to muscle weakness and disability, CMAP sum score may be a good marker in the evaluation of patients with anti-MAG neuropathy.

A preoperative metabolic marker of parkinsonian apathy following subthalamic nucleus stimulation.

BACKGROUND: Subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) has been associated with the development of postoperative apathy. Debate on the causes of postoperative apathy continues, and the dominant hypothesis is that stimulation or dopaminergic drug reductions are causal in its development. We hypothesized that a preoperative predisposition to apathy also could exist. To this end, we sought to identify a preoperative metabolic pattern using [(18)]Fluorodeoxyglucose Positron Emission Tomography (PET), which could be associated with the occurrence of postoperative apathy after STN-DBS for PD. METHODS: Thirty-four patients with PD, not clinically apathetic, underwent an [(18)]Fluorodeoxyglucose-PET scan before surgery of STN-DBS, and were tested for the occurrence of apathy 1 y after surgery. Whole-brain voxel-based PET intergroup comparison (P < 0.005; corrected for the cluster) was evaluated between patients who developed apathy at 1 y and those who did not. RESULTS: Eight patients (23.5%) became apathetic after surgery. Motor improvement and decrease in dopaminergic treatment were similar in both postoperative apathy and non-apathy groups. We found a cluster of significantly greater metabolism in the postoperative apathy group within the cerebellum, brainstem (in particular ventral tegmental area), temporal lobe, insula, amygdala, lentiform nucleus, subgenual anterior cingulate, and inferior frontal gyrus. A metabolic value above 68 could discriminate patients who would develop postoperative apathy with 100% sensitivity and 88.5% specificity. CONCLUSIONS: We describe a preoperative metabolic pattern associated with the development of apathy after STN-DBS in PD. This suggests the existence of a predisposition to apathy, which may further be triggered by perioperative drug modifications.

Fibromyalgia-like symptoms associated with irritable bowel syndrome: A challenging diagnosis of late-onset Pompe disease.

INTRODUCTION: Late-onset Pompe disease (LOPD) is a rare autosomal recessive disorder which usually presents as a limb-girdle myopathy with early respiratory involvement. METHODS: We report 2 sisters with an uncommon presentation of LOPD characterized by fibromyalgia-like pain associated with irritable bowel syndrome. RESULTS: In both sisters, clinical examination was normal and had remained stable for 10 years. The serum creatine kinase level was mildly elevated. Several muscle biopsies showed slight nonspecific myopathic abnormalities. A dried blood spot test indicated acid maltase deficiency. The diagnosis of LOPD was confirmed genetically. Both sisters subsequently developed proximal muscle weakness after pregnancy and started enzyme replacement therapy. Under treatment, gastrointestinal symptoms improved, but pain persisted. CONCLUSIONS: Clinicians should be aware of this atypical presentation of LOPD to enable earlier diagnosis and treatment.

Cardiovascular prevention of cognitive decline.

Midlife cardiovascular risk factors, including diabetes, hypertension, dyslipemia, and an unhealthy lifestyle, have been linked to subsequent incidence, delay of onset, and progression rate of Alzheimer disease and vascular dementia. Conversely, optimal treatment of cardiovascular risk factors prevents and slows down age-related cognitive disorders. The impact of antihypertensive therapy on cognitive outcome in patients with hypertension was assessed in large trials which demonstrated a reduction in progression of MRI white matter hyperintensities, in cognitive decline and in incidence of dementia. Large-scale database correlated statin use and reduction in the incidence of dementia, mainly in patients with documented atherosclerosis, but clinical trials failed to reach similar conclusions. Whether a multitargeted intervention would substantially improve protection, quality of life, and reduce medical cost expenditures in patients with lower risk profile has not been ascertained. This would require appropriately designed trials targeting large populations and focusing on cognitive decline as a primary outcome endpoint.