Klein, Christopher J

ABSTRACTInherited neuropathy is a group of common neurologic disorders with heterogeneous clinical presentations and genetic causes. Detailed neuromuscular evaluations, including nerve conduction studies, laboratory testing, and histopathologic examination, can assist in identification of the inherited component beyond family history. Genetic testing increasingly enables definitive diagnosis of specific inherited neuropathies. Diagnosis, however, is often complex, and neurologic disability may have both genetic and acquired components in individual patients. The decision of which genetic test to order or whether to order genetic tests is often complicated, and the strategies to maximize the value of testing are evolving. Apart from rare inherited metabolic neuropathies, treatment approaches remain largely supportive. We provide a clinical update of the various types of inherited neuropathies, their differential diagnoses, and distinguishing clinical features (where available). A framework is provided for clinical evaluations, including the inheritance assessment, electrophysiologic examinations, and specific genetic tests.Muscle Nerve48: 604–622, 2013

ABSTRACTIntroductionThe clinical significance of striational antibodies (StrAbs) detected in the course of paraneoplastic antibody testing is unknown.MethodsWe compared all 203 striational antibody (StrAb)‐seropositive patients identified (2004–2005) during evaluation for paraneoplastic antibodies with age‐ and sex‐matched seronegative controls.ResultsThymoma and myasthenia gravis (MG) were significantly more common among cases (P<0.0001). Cancers more rarely detected after StrAb detection were adenocarcinoma in 5 patients and sarcoma in 3 patients. All patients who had a cancer identified after StrAb testing had a titer of ≥1:7680 or a coexisting muscle AChR‐binding antibody. Autoimmune disorders more commonly observed among cases (with any StrAb value) included: hypothyroidism; rheumatoid arthritis; and pernicious anemia (all P<0.05).ConclusionsStrAbs may serve as a diagnostic clue for an autoimmune diagnosis. There is a low likelihood of oncological significance in patients with StrAb titers <1:7680 without coexisting paraneoplastic Abs. Muscle Nerve, 2013

ABSTRACTIntroductionThe aim of this study was to test the proficiency (accuracy among evaluators) of measured attributes of nerve conduction (NC).MethodsExpert clinical neurophysiologists, without instruction or consensus development, from 4 different medical centers, independently assessed 8 attributes of NC in 24 patients with diabetes mellitus (DM) on consecutive days.ResultsNo significant intraobserver differences between days 1 and 2 were found, but significant interobserver differences were seen. Use of standard reference values did not correct for these observed differences.ConclusionsInterobserver variability was attributed to differences in performance of NC. It was of sufficient magnitude that it is of concern for the conduct of therapeutic trials. To deal with interrater variability in therapeutic trials, the same electromyographers should perform all NC assessments of individual patients or, preferably, NC procedures should be more standardized. A further trial is needed to test whether such standardization would eliminate interobserver variability. Muscle Nerve 48: 369–374, 2013