Refined exercise testing can aid DNA-based diagnosis in XXXX .

@entity1 @entity17631 @entity26322 @entity1372 @entity12296 @entity8525 @entity28846 @entity2865 @entity121
OBJECTIVE: To improve the accuracy of genotype prediction and guide genetic testing in @entity1 with @entity121 we applied and refined specialized electrophysiological exercise test parameters. METHODS: We studied 56 genetically confirmed @entity1 and 65 controls using needle electromyography, the long exercise test, and short exercise tests at room temperature, after cooling, and rewarming. RESULTS: Concordant amplitude-and-area decrements were more reliable than amplitude-only measurements when interpreting patterns of change during the short exercise tests. Concordant amplitude-and-area pattern I and pattern II decrements of >20% were 100% specific for paramyotonia @entity17631 , respectively. When decrements at room temperature and after cooling were <20%, a repeat short exercise test after rewarming was useful in @entity1 with @entity17631 . Area measurements and rewarming distinguished true temperature sensitivity from amplitude reduction due to cold-induced slowing of muscle fiber conduction. In @entity1 with negative short exercise tests, symptomatic @entity8525 predicted sodium channel @entity8525 @entity17631 . Distinctive "tornado-shaped" @entity12296 -like discharges may be seen in @entity1 with @entity28846 . In the long exercise test, area decrements from pre-exercise baseline were more sensitive than amplitude decrements-from-maximum-compound muscle action potential (CMAP) in @entity1 with @entity26322 . Possible ethnic differences in the normative data of the long exercise test argue for the use of appropriate ethnically-matched controls. INTERPRETATION: Concordant CMAP amplitude-and-area decrements of >20% allow more reliable interpretation of the short exercise tests and aid accurate DNA-based diagnosis. In @entity1 with negative exercise tests, specific clinical features are helpful in differentiating @entity1372 from @entity2865 channel @entity8525 . A modified algorithm is suggested.
