It's all in the Flow-Volume Curve: Kommerell Diverticulum presenting as Pseudo-Asthma
Asthma causes episodic bronchoconstriction due to bronchial hyper reactivity and contraction of the smooth muscle. Further inflammatory cascade lead to inflammation and mucus hyper secretion. Symptoms include cough, wheezing and dyspnea at rest or on exertion. These symptoms are also present in a number of condition including post nasal drip, cystic fibrosis or reflux in case of cough, vocal cord dysfunction, partial airway obstruction or by a mass, foreign body aspiration or from airway malacia; hyperventilation, anxiety and deconditioning in case of dyspnea. For patient Exercise-induced asthma is rarely exist without other respiratory symptoms at rest namely, cough and wheezing. for patient old enough to perform spirometry, or a challenge can help diagnose asthma by demonstrating a significant change in flows. Vascular anomaly causes obstruction of the central airway and malacia and no response to bronchodilator, a hallmark is the variable intra-thoracic obstruction appreciated in the flow-volume curve. We present a patient with dyspnea on exertion and pseudo asthma. This 11-year-old male presents with progressive dyspnea on exertion, “sounds wheezy” . He has no syncope. He failed to respond to Albuterol used before exercise and for shortness of breath. There is no exacerbation with viral illnesses or exposure to allergens. He reports sialorrhea during exercise. There was positive family history atopy. The environment is significant for rabbit. Allergy panel was negative. A previous Exercise testing was reported normal, but review of the flow volume curve showing a significant flattened expiratory loop suggested malacia from vascular ring. An exercise challenge was not contributory, patient had obstruction at baseline and did not reached the 85% of maximal heart rate, but continue showing the F-V curve abnormally. A Chest CT shows mild bronchial wall thickening with no bronchiectasis and right-sided aortic arch with aberrant left subclavian artery and prominent diverticulum of Kommerell's and compression of the posterior esophagus, but only mild contour deformity of the adjacent trachea. Echo cardiogram shows no other cardiac abnormality. The patient underwent surgical division of a ligament arteriosum for a right aortic arch with aberrant L subclavian artery and plication of the Kommerell's diverticulum to the posterior chest. He was well at return and follow up spirometry shows unchanged FEV1 with persistent flattened expiratory flow. Conclusion Vascular ring and Kommerell's diverticulum can be symptomatic and present as pseudo-asthma. The NIH guidelines recommend spirometry for diagnosis, assess severity and control. The flow-volume curve need to be assessed.