Case Report
Congenital Cystic Adenomatoid Malformation of Lung Sqn Ldr S Sahu*, Wg Cdr S Muthuvel+, Col SS Naware#, Wg Cdr SS Dhavala** MJAFI 2008; 64 : 268-269 Key Words : Congenital cystic adenomatoid malformation;Pneumothorax
Introduction ongenital cystic adenomatoid malformation (CCAM) is a rare entity and is considered as a focal pulmonary dysplasia. Rarity of this lesion can be assessed from the fact that in a teaching 600 bedded hospital with a clientele of 3,50,000 there were only 12 cases reported over a period of 16 years [1]. In another study, the incidence was 1:25000 to 1:35000 pregnancies [2]. It is defined as a multicystic mass of a pulmonary tissue in which there is proliferation of immature bronchial structures at the expense of alveolar development [1]. It represents 25% of congenital lung malformations and 95% of congenital lung lesions [3]. This lesion occurs more often in males with a ratio of 1.8:1, and is primarily unilateral, but may occur bilaterally [4]. Associated anomalies are rare. Some CCAM lesions present only at birth with respiratory distress symptoms but are confirmed by an abnormal chest radiograph or computed tomography scan. We present a case of CCAM in a child who presented with features of pneumothorax.
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Case Report A two year old female child presented with complaints of sudden onset of breathlessness and pain in the left side of chest. Clinically there was no air entry on the left side. An urgent radiograph chest revealed a large pneumothorax with collapsed left lung. Few cystic lesions were noted in the collapsed portion of the left lung. No significant mediastinal shift was noted and there was no herniation of the affected lung to contralateral side. To relieve the breathlessness, a needle was put into the left hemithorax and after initial drainage of air it was followed up with ICD drainage. On follow up radiograph there was complete opacification of the left hemithorax with few cystic lesions in the left lower zone. A provisional diagnosis of CCAM Type I was offered. Blood and biochemical parameters did not reveal any significant finding. Computed tomography (CT) scan showed hydropneumothorax on the left side with multiple large cystic
lesions including the lingular lobe of left lung. The largest cyst measured 36X24mm. There was subpleural cystic lesion seen on left side. The child underwent a lobectomy at a tertiary care hospital. Histopathology proved the diagnosis of congenital cystic adenomatoid malformation. At present the child is completely asymptomatic and on regular follow up.
Discussion Histological classification of CCAM was first described in 1977 [5]. The Stocker classification system divides the lesions into three groups. The Stocker Type I, accounts for 50-70% of diagnosed cases. It is composed of single or multiple large cysts (3 to 10 cm), confined to one lobe and filled with air or fluid. Only 11% of these lesions are complicated with associated anomalies and majority of these patients survive. Our case fits into this group. CCAM Stocker Type II lesions found in 18-40% of cases, consist of multiple evenly distributed, medium sized cysts (
Congenital Cystic Adenomatoid Malformation of Lung Sqn Ldr S Sahu*, Wg Cdr S Muthuvel+, Col SS Naware#, Wg Cdr SS Dhavala** MJAFI 2008; 64 : 268-269 Key Words : Congenital cystic adenomatoid malformation;Pneumothorax
Introduction ongenital cystic adenomatoid malformation (CCAM) is a rare entity and is considered as a focal pulmonary dysplasia. Rarity of this lesion can be assessed from the fact that in a teaching 600 bedded hospital with a clientele of 3,50,000 there were only 12 cases reported over a period of 16 years [1]. In another study, the incidence was 1:25000 to 1:35000 pregnancies [2]. It is defined as a multicystic mass of a pulmonary tissue in which there is proliferation of immature bronchial structures at the expense of alveolar development [1]. It represents 25% of congenital lung malformations and 95% of congenital lung lesions [3]. This lesion occurs more often in males with a ratio of 1.8:1, and is primarily unilateral, but may occur bilaterally [4]. Associated anomalies are rare. Some CCAM lesions present only at birth with respiratory distress symptoms but are confirmed by an abnormal chest radiograph or computed tomography scan. We present a case of CCAM in a child who presented with features of pneumothorax.
C
Case Report A two year old female child presented with complaints of sudden onset of breathlessness and pain in the left side of chest. Clinically there was no air entry on the left side. An urgent radiograph chest revealed a large pneumothorax with collapsed left lung. Few cystic lesions were noted in the collapsed portion of the left lung. No significant mediastinal shift was noted and there was no herniation of the affected lung to contralateral side. To relieve the breathlessness, a needle was put into the left hemithorax and after initial drainage of air it was followed up with ICD drainage. On follow up radiograph there was complete opacification of the left hemithorax with few cystic lesions in the left lower zone. A provisional diagnosis of CCAM Type I was offered. Blood and biochemical parameters did not reveal any significant finding. Computed tomography (CT) scan showed hydropneumothorax on the left side with multiple large cystic
lesions including the lingular lobe of left lung. The largest cyst measured 36X24mm. There was subpleural cystic lesion seen on left side. The child underwent a lobectomy at a tertiary care hospital. Histopathology proved the diagnosis of congenital cystic adenomatoid malformation. At present the child is completely asymptomatic and on regular follow up.
Discussion Histological classification of CCAM was first described in 1977 [5]. The Stocker classification system divides the lesions into three groups. The Stocker Type I, accounts for 50-70% of diagnosed cases. It is composed of single or multiple large cysts (3 to 10 cm), confined to one lobe and filled with air or fluid. Only 11% of these lesions are complicated with associated anomalies and majority of these patients survive. Our case fits into this group. CCAM Stocker Type II lesions found in 18-40% of cases, consist of multiple evenly distributed, medium sized cysts (
