Stimulated jitter analysis for the evaluation of neuromuscular junction disorders in children.

INTRODUCTION

Stimulated jitter analysis (stim-JA) using a concentric needle electrode is a technique used to study the neuromuscular junction (NMJ) without voluntary activation. Our objective was to study the diagnostic sensitivity, specificity, and feasibility of stim-JA in infants and children with suspected NMJ defects.

METHODS

Sixteen infants and young children ages 2 months to 17 years with suspected NMJ disorders were evaluated using stim-JA over a period of 12 months.

RESULTS

Subjects with suspected NMJ defects and abnormal stim-JA subsequently had laboratory confirmation of myasthenia gravis (n = 5) and infant botulism (n = 2). Turnaround time for confirmatory laboratory tests was 6.0 ± 4.3 days, whereas stim-JA results were available immediately. All subjects tolerated stim-JA well without complications or need for sedation.

CONCLUSIONS

Stim-JA is a sensitive and safe first-line diagnostic test for evaluation of suspected pediatric NMJ disorders. Stim-JA results precede assay results and may guide early treatment.