INTRODUCTION:Allergic bronchopulmonary aspergillosis (ABPA) was first described in 1952 by Hinton in three patients with asthma who demonstrated sensitization to Aspergillus funigatus and “recurrent pyrexial attacks, radiological evidence of recurrent collapse, purulent sputum-containing plugs and blood eosinophilia.” Subsequently, ABPA has been described in patients with cystic fibrosis (CF). In this report, we describe a case of ABPA presenting in a man with Mounier-Kuhn syndrome (congenital tracheobronchomegaly).
CASE PRESENTATION:A 53 year old Puerto Rican male first presented to our service in 2000 with persistent wheezing. He had a history of heavy tobacco use, and was on methadone maintenance for prior substance abuse. In subsequent years he had multiple medical visits and hospital admissions for presumed COPD exacerbations treated with antibiotics and steroids. In June 2005 he was admitted to the hospital for fevers, productive cough, and significant dyspnea despite treatment with antibiotics and steroids. A chest CT showed tracheomegaly (maximum diameter 37mm), tracheal diverticulosis, central bronchiectasis and multiple ground-glass opacities. Bronchoscopy revealed tracheomegaly and tracheomalacia with expiratory collapse of the central airways. Bronchial lavage was negative for PCP, CMV, AFB and malignancy and grew normal flora. Spirometry demonstrated obstructive airways dysfunction with saw-toothing of the expiratory flow-volume loop. Based on the bronchoscopic, radiologic, and spirometric findings a diagnosis of Mounier-Kuhn syndrome (MKS) was made. During subsequent admissions repeat bronchoscopies were performed due to recurrent migratory infiltrates in a patient on chronic steroids and results were similar to the initial bronchoscopy. Central bronchiectasis, migratory infiltrates, a serum total IgE of 876 IU/L, and radio-allergosorbent testing for specific IgE showing a class 6 response to Aspergillus fumigatus were consistent with the concomitant diagnosis of ABPA.
DISCUSSIONS:MKS is a congenital abnormality of the trachea and main bronchi resulting in tracheobronchomalacia. The trachea and main bronchi become flaccid and markedly dilated on inspiration, and collapse with expiration or coughing. This central airway flaccidity is a result of weakening of the membranous and cartilaginous central airways associated with atrophy/absence of longitudinal elastic fibers and thinning of the muscularis mucosa. Tracheal diverticulosis is often observed on CT scanning. The clinical manifestations are akin to bronchiectasis and include coughing, copius mucopurulent sputum, and recurrent pulmonary infections, often leading to a misdiagnosis of COPD. Tracheomegaly is generally defined as a trachea measuring more than 30mm in transverse diameter on an erect PA film or above 21.8 mm in men on CT imaging. A review of case reports of MKS revealed that the majority of patients presented in or after their fourth decade of life commonly presenting with hemoptysis or symptoms of bronchiectasis. The description of ABPA by Hinton et al still serves as the core diagnostic criteria for this disease. Diagnostic criteria include: 1)asthma 2)immediate skin reactivity to Aspergillus 3) Current or previous pulmonary infiltrates 4)Elevated total serum IgE, 5)peripherial blood eosinophila 6)Serum precipitants to A. fumigatus, 7)central bronchiectasis, and 8)Elevated serum IgE-A. fumigatus and IgG-A. fumigatus. Although asthma is one of the eight diagnostic criteria for ABPA, ABPA is also reported in as many as 11% of patients with CF. To our knowledge, there have been no reported cases of ABPA in association with MKS.
CONCLUSION:Clinicians should be aware of the association of ABPA with structural airway diseases other than asthma and cystic fibrosis.
DISCLOSURE:Amit Patel, No Financial Disclosure Information; No Product/Research Disclosure Information