Seronegative myasthenia gravis (MG) presents a serious gap in MG diagnosis and understanding. We applied a cell based assay (CBA) for the detection of muscle specific kinase (MuSK) antibodies undetectable by radioimmunoassay. We tested 633 triple-seronegative MG patients' sera from 13 countries, detecting 13% as positive. MuSK antibodies were found, at significantly lower frequencies, in 1.9% of healthy controls and 5.1% of other neuroimmune disease patients, including multiple sclerosis and neuromyelitis optica. The clinical data of the newly diagnosed MuSK-MG patients are presented. 27% of ocular seronegative patients were MuSK antibody positive. Moreover, 23% had thymic hyperplasia suggesting that thymic abnormalities are more common than believed.
26 July 2005 in Journal of Neurology, Neurosurgery & Psychiatry
The aim of this study was to describe the clinical characteristics of atypical lacunar syndrome (ALS) based on data collected from a prospective acute stroke registry. In total, 2500 acute stroke patients were included in a hospital based prospective stroke registry over a 12 year period, of whom 39 were identified as having ALS and radiologically proven (by computed tomography or magnetic resonance imaging) lacunes. ALS accounted for 1.8% of all acute stroke patients, 2.1% of acute ischaemic stroke, and 6.8% of lacunar syndromes. ALS included dysarthria facial paresis (n = 12) or isolate dysarthria (n = 9), isolated hemiataxia (n = 4), pure motor hemiparesis with transient internuclear ophthalmoplegia (n = 4), pure motor hemiparesis with transient subcortical aphasia (n = 3), unilateral (n = 2) or bilateral (n = 3) paramedian thalamic infarct syndrome, and hemichorea hemiballismus (n = 2). Atypical lacunar syndromes were due to small vessel disease in 96% of patients. Atherothrombotic infarction occurred in one patient and cardioembolic infarct in another, both presenting pure dysarthria. Outcome was good (in hospital mortality 0%, symptom free at discharge 28.2%). After multivariate analysis, the variables of speech disturbances, nausea/vomiting, ischaemic heart disease, and sensory symptoms were found to be significantly associated with ALS. In conclusion, atypical lacunar syndrome is an infrequent stroke subtype (one of each 14 lacunar strokes). ALS occurred in 6.8% of lacunar strokes. Isolated dysarthria or dysarthria facial paresis were the most frequent presenting forms. The prognosis of this infrequent non-classic lacunar syndrome is good.
Charcot‐Marie‐Tooth (CMT) disease or hereditary motor and sensory neuropathy (HMSN) is a genetically heterogeneous group of conditions that affect the peripheral nervous system. The disease is characterized by degeneration or abnormal development of peripheral nerves and exhibits a range of patterns of genetic transmission. In the majority of cases, CMT first appears in infancy, and its manifestations include clumsiness of gait, predominantly distal muscular atrophy of the limbs, and deformity of the feet in the form of foot drop. It can be classified according to the pattern of transmission (autosomal dominant, autosomal recessive, or X linked), according to electrophysiological findings (demyelinating or axonal), or according to the causative mutant gene. The classification of CMT is complex and undergoes constant revision as new genes and mutations are discovered. In this paper, we review the most efficient diagnostic algorithms for the molecular diagnosis of CMT, which are based on clinical and electrophysiological data.