Laboratory Evaluation of Vocal Fold Paralysis and Paresis

Abstract

This study aimed to assess the value of comprehensive laboratory evaluation in patients with vocal fold paralysis or paresis. This is a retrospective chart review. Records of 231 patients with vocal fold paralysis or paresis were reviewed to determine whether there is a significant increase in the number of abnormal test results compared with rates of abnormal results for these tests in the general population and whether testing resulted in clinically important diagnosis. Laboratory data were collected from charts from initial visits from 2010 to 2014 and compared with national data. When controlled for age and sex, white blood cell count was found to have a significantly higher rate of abnormal test results (P < 0.001) in patients with vocal fold paralysis or paresis than the general population. Although hemoglobin, thyroid-stimulating hormone, and thyroid antibody tests were more likely to be abnormal in our patient population, the trend was not statistically significant. Further, the prevalence of syphilis and myasthenia gravis was found to be higher in these subjects than their respective national prevalences, and the incidence of Lyme disease was found to be higher than the national prevalence of Lyme disease. Several patients were diagnosed with medically important conditions such as diabetes, thyroid dysfunction, syphilis, myasthenia gravis, and Lyme disease based on these tests. This study suggests that comprehensive testing of patients with vocal fold movement disorders results in diagnoses that would be missed without a comprehensive evaluation, some of which are important medically, although their causal relationship to vocal fold paralysis or paresis was not investigated or established.