A Clinical Classification Scheme for Tracheobronchomegaly (Mounier-Kuhn Syndrome).

INTRODUCTION: Tracheobronchomegaly (Mounier-Kuhn Syndrome) is a rare disease characterized by tracheal enlargement and associated loss of elastic fibers in the trachea and main bronchi. MATERIALS: MEDLINE, Index Medicus, and other databases were searched with pre-defined criteria to identify cases of tracheobronchomegaly (TBM). Two new cases of TBM were also identified from the Provincial Medical Genetics Program of British Columbia. RESULTS: We identified 166 publications describing 365 occurrences of TBM. We observed that affected individuals could be grouped into subgroups according to clinical features. Type 1A (105 individuals) consists of infants who developed TBM after having undergone fetoscopic tracheal occlusion, and Type 1B patients (24 individuals) are infants and children who developed TBM after prolonged intubation. Type 2 individuals developed TBM following recurrent pulmonary infections (2A) (14 individuals) or pulmonary fibrosis (2B) (10 individuals). Type 3 represents TBM with evidence of extra-pulmonary elastolysis (18 individuals), and Type 4 denotes the development of TBM with no clear predisposing factors (196 individuals). Both of our patients had TBM and evidence of extra-pulmonary elastolysis. As well, one patient had a mildly dilated aortic root, which is a previously unreported co-occurrence. CONCLUSION: We introduce a novel classification scheme, which may sort patients into etiologically distinct groups, furthering our understanding of its pathogenesis and potentially, prevention or therapy. We also hypothesize that TBM and generalized elastolysis may have etiological commonalities, suggesting a need for further study.

Tracheobronchomegaly following intrauterine tracheal occlusion for congenital diaphragmatic hernia.

BACKGROUND: Fetuses with severe congenital diaphragmatic hernia (CDH) and pulmonary hypoplasia may benefit from fetal endoluminal tracheal occlusion (FETO). Enlargement of the main bronchi and trachea appears to be a common complication of FETO. OBJECTIVE: To retrospectively evaluate the trachea and main bronchi of infants who underwent FETO for CDH and compare diameters with age-matched references. MATERIAL AND METHODS: Postnatal and follow-up chest radiographs were performed in seven children with unilateral CDH treated by FETO. Additional CT was performed in six of these (one neonate died before CT could be performed). Images were acquired from 3 days to 23 months of age. For each child, radiographs and CT images with optimal visualisation of the airways were selected for retrospective analysis. Tracheal and bronchial morphology was assessed by two experienced paediatric radiologists, and the diameters of these structures measured and compared with age-matched references. RESULTS: Mean diameters of the trachea and main bronchi were above the age-matched normal range in all patients, regardless of the side of the hernia or the degree of lung hypoplasia. CONCLUSION: Enlargement of the trachea and main bronchi appears following FETO and persists at least to the age of 5 years.

Tracheomegaly: a complication of fetal endoscopic tracheal occlusion in the treatment of congenital diaphragmatic hernia.

BACKGROUND: Fetal endoscopic tracheal occlusion (FETO) is a promising treatment for severe congenital diaphragmatic hernia, a condition that carries significant morbidity and mortality. It is hypothesised that balloon occlusion of the fetal trachea leads to an improvement in lung growth and development. The major documented complications of FETO to date are related to preterm delivery. OBJECTIVE: To report a series of five infants who developed tracheomegaly following FETO. MATERIALS AND METHODS: Review of all children referred with tracheomegaly to the paediatric intensive care and tracheal service at two referral centres. RESULTS: Five neonates presented with features of respiratory distress shortly after birth and were subsequently found to have marked tracheomegaly. Two neonates had tracheomalacia in addition. CONCLUSION: There are no previous reports in the literature describing tracheomalacia, or more specifically, tracheomegaly, as a consequence of FETO. We propose that the particularly compliant fetal airway is at risk of mechanical damage from in utero balloon occlusion. This observation of a new problem in this cohort suggests a thorough evaluation of the trachea should be performed in children who have had FETO in utero. It may be that balloon occlusion of the trachea earlier in utero (before 26 weeks' gestation) predisposes to this condition.

Tracheal enlargement or Mounier-Kuhn syndrome in giant cell arteritis: a possible causal association with therapeutic implications.

Giant cell arteritis (GCA) is a large-vessel vasculitis with rarely described respiratory initial manifestations. We report such a case presenting with hoarseness, stridor, cough and dyspnea, in which a tracheomegaly with tracheomalacia was found. No signs of relapsing polychondritis were present. The respiratory symptoms rapidly improved after glucocorticoids and Azathioprine. Tracheomegaly or Mounier-Kuhn syndrome is characterized by marked dilatation of trachea and central bronchi. The differential diagnosis and the possible relationship between tracheomegaly and GCA involving metalloproteinase-induced elastolysis are discussed. This is the first case, to our knowledge, of Mounier-Kuhn syndrome in vasculitis. The association of tracheomegaly with GCA may be underestimated, as the diagnosis is not always obvious on conventional radiographs. A tracheal enlargement finding in GCA requires monitoring to ensure early detection and prevention of spontaneous tracheal rupture. Adding a metalloproteinase inhibitor like Doxycycline to GCA therapy would be rational for the prophylaxis of complications.

Tracheobronchomegaly associated with laryngo-tracheal amyloidosis: First case report.

Tracheobronchomegaly (TBM) is a rare enlargement of the tracheal cartilage, also known as Mounier-Kuhn syndrome (MKS). Here, we describe an unusual case of acquired TBM in an adult, caused by amyloid regeneration and associated tracheal weakening, rather than by MKS. CT scan and fiberscopic examination of a 55-year-old woman suffering from severe dyspnea revealed TBM and subglottic stenosis, which was caused by deposition of amyloid tissue. We performed a tracheostomy and vaporized the subglottic stenosis with a CO2 laser, after which we installed a silicone T-tube. After the first operation, re-stenosis occurred, and the procedure was repeated; stenosis was subsequently cured and the dyspnea disappeared, after which the tracheostomy could be closed. This is the first report of adult TBM associated with amyloid deposition in the subglottis and trachea. This diagnosis is very difficult, as amyloid deposition in the trachea can have various clinical presentations.

Acquired tracheobronchomegaly resulting in severe respiratory failure.

Tracheobronchomegaly is a distinct clinical and radiologic entity characterized by marked dilatation of the trachea and bronchi. In this report we describe a Marfanoid patient who developed TBM in his adulthood with rapid deterioration, leading to hypercapnic respiratory failure. This case represents an acquired form of TBM in a patient with Marfanoid features which has not been previously described. Tracheobronchomegaly should be considered as a cause of chronic respiratory failure in a young adult and can be diagnosed easily with chest roentgenogram and CAT scan.

Rapidly progressing case of Mounier-Kuhn Syndrome in early childhood.

Reports of Mounier-Kuhn Syndrome in childhood are extremely rare, as it usually presents in the third or fourth decades. In the only other report of a case diagnosed in early childhood, the child was well at the time of publication. We report on a 15-month-old boy who presented with his first respiratory illness at age 3 months. His disease course was more severe than previously reported. Diagnosis was characteristically delayed until acute respiratory failure complicated a respiratory tract infection at 13 months, prompting high-resolution computerized tomography (HRCT) of the chest. He gradually deteriorated, eventually requiring ventilatory support; death occurred at age 15 months. This report illustrates the clinical heterogeneity of the syndrome. We review the theories about etiology and the recognized clinical findings in adults. Incidence may be higher than previously estimated, and tracheobronchomegaly (TBM) should be considered as a cause of respiratory failure and recurrent pneumonia in children where other investigations, including chest X-ray (CXR), are normal. A chest HRCT (cHRCT) scan and bronchoscopy are usually diagnostic.

Atypical peritracheobronchial vasculitis and an effective treatment.

We report an interesting case of vasculitis in which the inflammatory lesion was limited to the peritracheobronchus. This case showed positive antineutrophil cytoplasmic antibodies, diffuse peritracheobronchial swelling, and vasculitis in its histology. Steroid therapy was effective for both roentgenological and serological findings. Although the biopsy specimen shows only inflammation and does not satisfy the WHO criteria of Wegener's granulomatosis (WG), a possible diagnosis of WG should not be disregarded.

Tracheomegaly in children.

Three children with tracheomegaly were studied by CT scan at The Children's Hospital of Philadelphia. Normal age-related tracheal dimensions were obtained from a study by Griscom (1). Tracheomegaly was defined as tracheal dimensions greater than 2 SD above normal. In two of our patients, tracheomegaly was associated with intubation and ventilatory support, and in the third, it was associated with recurrent pneumonia and chronic bronchitis. In this article, we discuss the etiologies of tracheomegaly in our patients and review the literature on the subject.

[Treatment of tracheobronchomegaly with an Ultraflex prosthesis. A case report]. / Traitement de la trachéobronchomégalie par la mise en place d'une prothèse Ultraflex.

Tracheobronchomegaly is defined as a dilatation of the trachea and the large bronchi. It may occur as a familial condition or in association with a connective tissue disease, e.g. Ehlers-Danlos syndrome. Tracheobronchomegaly occurs late in adults. The predominant symptoms are bronchial irritation and recurrent bronchopulmonary infections (because of ineffective cough). Diagnosis is provided by thoracic imaging, particularly computed tomography that enables measuring the precise diameter of the trachea. We report the case of one patient with tracheobronchomegaly who was greatly improved after implantation of Ultraflex tracheobronchial prostheses.

[Tracheobronchomegaly--Mounier-Kuhn syndrome--case report and review of the literature]. / Tracheobronchomegalie--Mounier-Kuhn-Syndrom--Kasuistik und Literaturübersicht.

Tracheobronchomegaly is a rare disorder. A marked dilatation of the trachea and the main stem bronchi is the characteristic sign measured as an enlarged transverse diameter (mean +/- 3 SD). Bronchiectasis is usual. In about one third of the published cases a diverticulosis was described as demonstrated in one our cases. For diagnostic modern radiological methods (CT including 3 D reconstruction, MRT) and bronchoscopy are recommended. The number and seize of the diverticula are documented by tracheography or by bronchography. In a part of all cases of tracheobronchomegaly the cause of the disorder is known. Therefore a division into congenital and acquired tracheobronchomegaly is useful.

Tracheobronchomegaly in preterm infants on mechanical ventilation.

Tracheobronchomegaly (TBM) was diagnosed on chest radiographs as an apparent dilatation of the trachea and main bronchi in four premature infants on prolonged mechanical ventilation for respiratory distress syndrome. In a retrospective study, the parameters of assisted ventilation, the Apgar score, the presence of conatal or later infection, and hypotension were reviewed and analyzed as factors possibly contributing to the pathogenesis of TBM in these infants. The results lead to the conclusion that TBM in premature infants on prolonged ventilatory support is an acquired condition though a congenital defect cannot be excluded as a probable predisposing factor. In the etiopathogenesis of TBM, a repeated barotrauma of prolonged ventilation is a crucial factor while the severity of lung disease and the degree of prematurity, hypotension, infection, and generally poor clinical condition, all appear to be relevant in the development of TBM in a premature infant with respiratory distress syndrome.