Possible relationship between esophageal dilatation and severity of M. abscessus pulmonary disease

Objectives Recently, incidence of Mycobacterium abscessus (Mab) pulmonary disease (Mab-PD) is increasing worldwide. We aimed to identify factors associated with severity of Mycobacterium abscessus (Mab) pulmonary disease (Mab-PD). Methods All patients diagnosed as Mab-PD based on the official ATS/IDSA statement between 2017 January 1 and 2021 July 31 were included (n = 13). We reviewed medical records, bacteriological and laboratory data of the patients. Severity of lung lesions and esophageal diameters in chest CT were quantitatively evaluated. Gaffky score in the sputum was used as airway mycobacterial burden. We explored the factors associated with high CT score and high Gaffky score. Results Maximum diameter of esophagus (MDE) in severe disease (CT score >= 10) was greater than that in milder disease (CT score<10) (18.0 +/- 7.9mm, 9.3 +/- 3.1mm, respectively, p = 0.01), and MDE was well correlated with CT score (R = 0.69, p = 0.007). MDE in high mycobacterial burden group (Gaffky score >= 5) tended to be greater than that in low mycobacterial burden group (Gaffky score <5) (16.1 +/- 6.8mm, 10.1 +/- 5.5mm, respectively, p = 0.12), and MDE was well correlated with Gaffky score (R = 0.68, p = 0.009). Lung lesions were bilateral and predominant in middle or lower lobes. Conclusions Esophageal dilatation was correlated with severity of Mab-PD and airway mycobacterial burden. Gastroesophageal reflux might be associated with Mab disease progression.