A surprising finding in an adolescent athlete affected by diffuse congenital cystic adenomatoid malformation (CCAM) (original) (raw)

The clinical respiratory journal, 2013

Abstract

Data from large population registries suggest an incidence of congenital lung cysts in the range of 1 per 8300–35 000 live births (1). Congenital cystic adenomatoid malformation (CCAM) is a developmental, non-hereditary hamartomatous abnormality of the lung with adenomatoid cyst proliferation, firstly described in 1949 by Ch’in and Tang (2). It is believed to be the result of a bronchial atresia or maturation arrest in bronchopulmonary segments at/before the seventh gestational week, producing dysplastic lung growth beyond the atretic segments (3) and cystic distortion of the lung architecture. Most CCAMs are detected antenatally by ultrasound, presenting with respiratory distress in the neonatal period; infants with large lesions may have respiratory insufficiency. The malformation is usually unilateral and sublobar or lobar in size, but occasionally, it can be multilobar or even bilateral with no special predilection for any lobe (4, 5). Only 10% of primary diagnoses are made after the first year of life (5, 6), and rarely the presentation of CCAM is delayed until adulthood. Computed tomography (CT) scan is the investigation of choice with a good accuracy (66.7%) in characterising the various types of CCAM. CCAMs symptoms include frequent chest infections, bronchiectasis, lung abscess, haemoptysis, pneumothorax, air embolism, haemothorax, pyopneumothorax, steroid resistant bronchospasm or rarely bronchioloalveolar carcinoma, blastomas and rhabdomyosarcoma. The treatment is usually surgical, involving complete resection of the affected parenchyma. This prevents recurrent infections and development of neoplastic transformation. The CCAMs Stocker classification (7) was based on the clinical and histological features and originally divided into three types (1, 2 and 3). CCAMs Type 1 account for 70% of cases, and are characterised by single or multiple cysts more than 3 cm in diameter; the cyst wall contains elastic tissue, smooth muscle and fibrovascular connective tissue. CCAMs Type 2 (approximately the 20–25% of cases) are characterised by multiple small cysts, 2 cm in diameter (rarely larger); mucous cells and cartilage are absent, and striated muscle fibres may occasionally be seen. CCAMs Type 3 are rare (approximately the 8% of cases) and characterised by cysts not larger than 1.5 cm in diameter; mucous cells, cartilage and striated muscle fibres are absent. Usually, CCAMs Type 3 involve a lobe of lung and have a spongy-like appearance, constructed by bulk gland-like structures. Types 0 and 4 CCAMs were subsequently proposed (8), and the term congenital pulmonary airway malformation was proposed instead of CCAM. CCAMs Type 0 account <2% of cases, and are the less frequently observed among CCAM lesions and incompatible with life. Clinically, infants present cyanosis and severe respiratory distress at birth and survive only few hours unless treated with extracorporeal membrane oxygenation; they are unable to survive without this support. Microscopically, the tissue consists entirely of bronchial-like structures with muscle, glands, numerous cartilage plates and small cysts (<0.5 mm); more distal components, such as proximal bronchioles, are only rarely seen. CCAMs Type 4 account between 10% and 15% of cases, and consist of multiple large cysts (up to 15 cm) lined only with Type 1 and 2 alveolar cells. Children with this malformation vary in age at presentation from 1 day to 4 years and display various degrees of respiratory distress. It may involve more than one lobe in 20% of cases, and resection is usually curative even with bilateral involvement (9). We report a case of diffuse, bilateral CCAM associated with allergic bronchial asthma, discovered in an adolescent with few symptoms. A 13-year-old Caucasian boy, sensitised to dust mites and grass pollen with a clinical history of respiratory distress at birth, was resolved in the second day of life with oxygen therapy. In the first year of life, he showed recurrent episodes of cough and bronchospasm treated with bronchodilators. In the subsequent years, he was healthy and reported wheezing only after intense physical exercise; he practiced daily martial arts. The boy came to our department for the Pre-Competition Medical Assessment when he was 12 years old. Pulmonary function tests showed severe airflow obstruction [forced expiratory volume in 1 s (FEV1) 49.0%, FEV1/ forced vital capacity 70.0% and maximum expiratory flow 50 24.7% of the predicted values] reversible after inhalation of 400 mcg of salbutamol (FEV1 + 16.3%). For this reason, he started a daily antiasthmatic therapy The Clinical Respiratory Journal

Annalisa di Coste hasn't uploaded this paper.

Let Annalisa know you want this paper to be uploaded.

Ask for this paper to be uploaded.