Laryngeal electromyography in amyotrophic lateral sclerosis.

BACKGROUND: Bulbar involvement is a hallmark of amyotrophic lateral sclerosis (ALS), but surprisingly very few studies have addressed the frequency, pattern and clinical relevance of laryngeal involvement in the disease. METHODS: Twenty-six patients with spinal-onset ALS underwent nasofibroscopy (NF), followed by laryngeal electromyography (LEMG). We also studied resting activity and motor unit potentials of the genioglossus and masseter muscles. RESULTS: Twenty-four patients presented neurogenic changes in at least one laryngeal muscle. There were fibrillation and/or fasciculation potentials associated with chronic neurogenic changes in the same muscle in 16 patients; of these, 9 had no alteration in the genioglossus. We found no patient with tongue neurogenic changes and normal LEMG. NF was abnormal in 14 patients; in the remaining 12, LEMG identified neurogenic changes in 11 of them. CONCLUSION: LEMG is able to identify laryngeal denervation in patients with ALS, sometimes before clinical manifestations are noticed. This technique may be a useful diagnostic tool for selected patients with suspicion of ALS.

Prevalence, Incidence, and Clinical-Epidemiological Characterization of Amyotrophic Lateral Sclerosis in Antioquia: Colombia.

INTRODUCTION: The prevalence and incidence of amyotrophic lateral sclerosis (ALS) is not fully established, and this varies depending on the studied population. OBJECTIVE: To estimate the prevalence/incidence of ALS patients in Antioquia-Colombia. METHODOLOGY: Observational/descriptive study by reviewing clinical records from 2010 to 2014. Cases with possible, probable and definite ALS were included. To estimate the prevalence/incidence, capture-recapture method was used. RESULTS: Point prevalence in December 2014 was 4.9/100,000 (95% CI 2.0-7.8), and the incidence was 1.4/100,000/year (95% CI 0.5-2.2). The median survival was 4 years. Spinal-onset was observed in 62.4% of the included patients. CONCLUSION: Prevalence, incidence and clinical presentation of ALS in Antioquia are similar to most studies reported worldwide. However, prevalence in Antioquia seems to be slightly higher than in other studies from Latin -American countries. This may derive from the inclusion criteria and case detection methodology adopted, but sociodemographic and genetic factors should be considered.