Discussion:
Congenital lesion of the lung in children is uncommon but potentially life-threatening, and warrants an urgent diagnostic work-up.7,8,9,10 These lesions may involve the lung parenchyma, bronchi, arterial supply, and venous drainage. They may present with respiratory symptoms at birth or may be detected incidentally either before or after birth. These lesions show close relationship in terms of embryology and clinical presentation. Despite the availability of the much-improved diagnostic modality the awareness of these anomalies among pediatricians is still lacking. The main reason behind the misdiagnosis of these cases is provisional diagnosis of Tuberculosis based on respiratory symptoms and a lesion on X-ray chest. In the parts of the world where Tuberculosis forms a prominent differential diagnosis of all chronic chest conditions, labelling these congenital lesions as tuberculosis is not surprising. These children are empirically prescribed ATT and in case of no response to ATT, the children are referred to higher centre for further management and hence these cases land up with us. Some cases of CLE and macro cystic variety of CCAM are misdiagnosed as pneumothorax and ICD insertion is done. But physicians soon realize that they are dealing with something else and they refer these cases, which form a major chunk of our study group. These mistakes do take place because of lack of awareness on part of physicians who do not suspect these conditions and hence do not look for them. Evidence for starting ATT or putting ICD is based on clinical examination, history and Chest X ray findings only. Clinical profile and Chest X ray are not enough to diagnose these lesions because of significant overlap of symptoms and X ray features. The gold standard for diagnosis of congenital lesion of lung in children is contrast enhanced computed tomography (CECT) chest. CCAMs presents as cystic or solid lung lesions confined to a part of lung only. They account for 25% of total congenital lesions and most commonly present with respiratory distress in newborns. Most of these lesions are now routinely diagnosed on prenatal ultrsonography.11,12,13,14 CCAM probably results from a cessation of bronchial maturation and concomitant overgrowth of mesenchymal elements, which produce the adenomatoid appearance of the anomaly in the early stage of development.15 CCAMs communicate with the bronchial tree at birth and therefore typically contain air soon after birth.13 The imaging appearance is determined by the size and number of cysts (figure 1). Lesions are typically solitary with no lobar predilection. Because of the risks of recurrent infection and malignant potential, resection remains the current treatment.13,14 Congenital lobar emphysema (CLE) is a marked pulmonary hyperinflation state that resembles all of the clinical features of obstructive emphysema.7,10,16,17 Congenital lobar emphysema usually involves a single lobe and presents with respiratory distress in the neonate.13,18Findings of air trapping with lobar hyperinflation, mediastinal shift away from the involved lung, and compression of the ipsilateral and contralateral lung. CT will show an expanded lobe with attenuated vascular structures (figure2). It is necessary for pediatricians to evaluate associated anomalies because 14% of the cases of CLE have coexistent congenital heart disease.19 Bronchopulmonary sequestrations (BPSs) make up10–30% of congenital cystic lung lesions. Pulmonary sequestration develops from abnormal budding of foregut and is characterized by non-functioning lung parenchyma that does not communicates with the tracheobronchial tree and have an anomalous systemic arterial supply. Bronchogenic cysts are the most common cystic lesion of the mediastinum. They usually present with recurrent infection or airway compression leading to wheezing, atelectasis, and air trapping and often present later in childhood than other congenital lung lesions. Detailed x ray and CECT chest findings of common congenital lesions of lung in children are shown in table 2.
In our study group 13 (48.1 %) cases were misdiagnosed by primary care providers and were unnecessarily subjected to either ATT or ICD which resulted in higher morbidity in these cases either due to delay in diagnosis and management or because of the treatment per se that is ICD which complicates the surgery. Point we would like to highlight by this study is that sooner or later all congenital lesions of lung will need surgical intervention whether symptomatic or not. Therefore, they need to be diagnosed correctly before starting any treatment whether ATT or ICD. Chest X ray is not sufficient enough for making a diagnosis, CECT chest should be done in all cases of congenital lesions of lung irrespective of the age and symptoms of presentation. Although the treatment of cystic lung lesions is quite straight forward, a strong index of suspicion is essential in diagnosing this uncommon entity. This entails prompt referral to a pediatric surgical centre thereby obviating unnecessary prolonged and needless medical management.
The author would like to declare that there is no conflicts of interest and this research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.