Subpleural lung cysts in Down's syndrome

Imaging of the rare cystic lung diseases

When discussing cystic lung diseases, a certain group of diseases tends to receive the majority of attention. Other less frequently discussed cystic lung diseases are also important causes of morbidity in patients. Etiologies include genetic syndromes, lymphoproliferative diseases, infections, exogenous exposures, and a developmental abnormality. This review article focuses on the clinical and imaging features of these other cystic lung diseases.

The evaluation and management of respiratory disease in children with Down syndrome (DS)

Children with Down syndrome (DS) have wide range of respiratory problems. Although underlying abnormalities in the respiratory system are important causes of morbidity and mortality in children with DS, particularly in the young, abnormalities in other organ systems may also impact respiratory function. A comprehensive evaluation of the child with DS and respiratory disease may prevent short-term morbidity and mortality, and reduce the incidence of complications in the long term. This review provides an overview of the various causes of respiratory disease, and insight into some of the newer therapies available to treat obstructive sleep apnea, in this population.

An overview of respiratory problems in children with Down's syndrome

Respiratory disease is a common cause of morbidity and mortality in children with Down's syndrome (DS). Causes range from those problems common to many children with DS, such as a narrow airway or impaired immunity, to rare structural lesions, such as tracheal bronchus. Additionally, other organ systems or extrinsic factors may play a role. A thorough understanding of the range of potential problems will aid in the evaluation and management of children with DS and respiratory symptoms.

Diagnostic Pathology of Diffuse Lung Disease in Children

The pathologic classification of diffuse lung disease in children and adolescents has undergone revision in recent years in response to rapid developments and new discoveries in the field. A number of important advancements have been made in the last 10 years including the description of new genetic mutations causing severe lung disease in infants and children, as well as the description of new pathologic entities in infants. These recently described entities, including ABCA3 surfactant disorders, pulmonary interstitial glycogenosis, and neuroendocrine cell hyperplasia of infancy, are being recognized with increasing frequency. This review will include brief discussion of the etiology and pathogenesis of the major groups of diffuse lung disease in children. Histopathologic features are discussed for each of the major categories of diffuse lung disease in children, beginning with the genetic, developmental, and alveolar growth disorders common in infancy, followed by brief discussion of airway diseases, immunologic diseases, and pulmonary vascular diseases seen more commonly in older children. A protocol for handling pediatric wedge lung biopsies is also discussed, which optimizes the diagnostic yield of lung biopsies in this population.

Subpleural lung cysts in Down syndrome: prevalence and association with coexisting diagnoses

BACKGROUND

Although subpleural cysts are known to be associated with Down syndrome, their etiology and prevalence remains unknown.

OBJECTIVE

To determine the prevalence of subpleural cysts in children with Down syndrome and the association with prematurity, congenital heart disease (CHD), extracorporeal membrane oxygenation (ECMO), and chronic ventilator support.

MATERIALS AND METHODS

A review of the CT examinations of 25 children with Down syndrome was performed to determine the presence, location, and distribution of cysts along with associated abnormalities. Charts were reviewed and coexistent diagnoses and past treatments were recorded.

RESULTS

The prevalence of subpleural cysts was 36% with no significant association with CHD, ECMO, or chronic ventilator support. An association was found in the two children with a history of prematurity. The cysts were most commonly found in the anteromedial portion of the lung.

CONCLUSION

Subpleural cysts are common in Down syndrome and should not be confused with another pathological process. An association with prematurity was found, but the low number of children in this study makes the connection uncertain. The etiology remains unclear, but it has been hypothesized that the cysts are associated with lung hypoplasia.

Acquired Nonneoplastic Neonatal and Pediatric Diseases

The lung biopsy is an established procedure to procure a pathologic diagnosis in a child with a suspected pneumonic process of undetermined etiology. Improvements in pediatric anesthesia and surgery have reduced the operative complications to a minimum. A biopsy can usually be taken through a small intercostal incision when localization is not especially important in a patient with diffuse changes (see Chapter 1). The alternative method for tissue sampling is the endoscopic transbronchial biopsy. There is less risk to the patient, but the specimen is smaller and crush artifacts from the instrument are more common.

Challenges in pulmonary fibrosis. 3: Cystic lung disease

Cystic lung disease is a frequently encountered problem caused by a diverse group of diseases. Distinguishing true cystic lung disease from other entities, such as cavitary lung disease and emphysema, is important given the differing prognostic implications. In this paper the features of the cystic lung diseases are reviewed and contrasted with their mimics, and the clinical and radiographic features of both diffuse (pulmonary Langerhans' cell histiocytosis and lymphangioleiomyomatosis) and focal or multifocal cystic lung disease are discussed.