Unusual Cause of Unexplained Chronic Cough: Aberrant Left Intrathoracic Muscle. Case report

Abstract

Cough is a vital reflex of protection of the airway that favors airway clearance and prevents aspiration. This can be generated by multiple etiologies, so it is convenient to classify it according to the time of evolution in acute, subacute and chronic cough, allowing a better approach and management. The chronic cough and especially the refractory to treatment or unexplained is defined as one in which multiple causes have been excluded and its triggering factors are not known, which has great impact on the quality of life of patients. We present the case of a female patient in the fifth decade of life, with a history of 8 years of evolution of unexplained chronic cough, who underwent studies. The chest CT scan showed scarce fibrotic bibasal tracts, retrocardiac bronchiectasis, left focal pleural thickening and left Bochdalek's hernia. Due to the tomographic diagnoses, Left Uniportal Video-Assisted Thoracic Surgery (VATS) was performed to take a biopsy of the pleural thickening, and pulmonary biopsy due to suspicion of unusual pulmonary fibrosis, and diaphragmatic hernia repair. This showed as incidental finding an aberrant intrathoracic muscle, which due to its site of origin and insertion, when contracted produced bronchial and diaphragmatic stimulation, that generated unexplained chronic cough, a finding that in the literature search has not been reported in any series or case report. After total resection of the muscle, the cough ceases.