INTRODUCTION
An uncommon, but potentially serious, cause of respiratory disorders in
childhood is represented by the extrinsic tracheal compression due to
congenital vascular anomalies within the mediastinum [1]. The most
severe forms are usually diagnosed during the neonatal period, while the
less severe forms can be detected later in life, when unexplained
chronic or recurrent respiratory symptoms, or occasional mild dysphagia,
lead to endoscopic evaluations. In two retrospective studies we found
that the most prevalent respiratory symptoms associated with this
condition were chronic cough, poorly responsive to therapy, and
recurrent lower respiratory tract infections (LRTI) [2,3]. In the
absence of known comorbidities, these symptoms are often misdiagnosed as
asthma, non-specific bronchial hyperreactivity and/or gastroesophageal
reflux and inappropriate prescription of anti-asthmatic drugs and/or
antibiotics often occurs [3,4]. The generation of cough in these
children is thought to be induced by mechanical sensory inputs, through
rapidly adapting mechanoreceptors [3,5]. The recurrence of LRTI in
these otherwise healthy children is believed to be related to the
dynamic collapse of the airway lumen, associated with malacia, that
reduces cough effectiveness and interferes with mucociliary clearance
[6-8]. Under-recognition and under-treatment of subclinical
protracted bacterial infections may lead to the development of chronic
suppurative lung disease and bronchiectasis [8]. With this
background a retrospective study was performed to evaluate whether
tracheal malacia, secondary to abnormal mediastinal vessels, is
associated with persistent lower respiratory tract inflammation and
infection.