Children’s interstitial lung disease (ChILD)
Dr Adam Jaffé, Paediatric Respiratory Consultant, Sydney Children’s Hospital, Randwick
Background: Interstitial Lung Disease in children (ChILD) is a group of rare lung conditions that causes chronic respiratory involvement and comprises a broader range of disorders than that seen in adults. This is likely to be due to the fact that these disorders occur on the background of a growing lung. There is some histological overlap with adult disease but there is an increasing recognition of interstitial diseases that are unique to children
Clinical Presentation: It is usually diagnosed within the first year of life. Older children may have similar characteristics to the processes is seen in adults. Children may present with recurrent cough, hypoxia, tachypnoea, subcostal recession, failure to thrive, crackles or wheeze.
Investigations:
- Chest X-ray
- Commuted tomography of the chest
- Infant lung function testing (if available)
- Surfactant protein mutations
- Bronchoscopy and bronchoalveolar lavage
- Lung biopsy
- Sleep study to assess degree of hypoxia
The differential diagnosis includes gastro-oesophageal reflux which may coexist but may also cause similar symptoms to ChILD.
Classification: In approximately 50% of cases the cause is unknown. A collaborative network in the United States has suggested the following as a novel classification scheme:
Diffuse developmental disorders of the lung: Acinar dysplasia Congenital alveolar dysplasia Alveolar capillary dysplasia with misalignment of pulmonary veins |
Lung growth abnormalities reflecting deficient alveolarisation: Pulmonary hypoplasia Chronic neonatal lung disease Related to chromosomal disorders Related to congenital heart disease |
Specific conditions of undefined cause:Neuroendocrine cell hyperplasia of infancy Pulmonary interstitial glycogenosis |
Inherited surfactant disorders:
|
Disorders related to systemic disease processes: Immune mediated/collagen vascular disorders Storage disease Sarcoidosis Langerhans cell histiocytosis Malignant infiltrates |
Disorders of the normal host: Related to infections Related to environmental agents -- hypersensitivity pneumonitis -- toxic inhalation Aspiration syndromes Eosinophilic pneumonia |
Disorders of the immunocompromised host:Opportunistic infections Related to therapeutic intervention Related to transplantation and rejection Diffuse alveolar damage, unknown aetiology |
Disorders masquerading as ILD: Arterial hypertensive vasculopathy Congestive changes related to cardiac dysfunction Veno-occlusive disease Lymphatic disorders |
| From Deutsch et al. Am J Resp Crit Care Med 2007:176;1120-1128 |
Treatment: Treatment depends on the cause of the interstitial lung disease. It is important to exclude and treat gastro-oesophageal acid reflux. In most cases treatment normally consists of using medications such as high-dose steroids, or alternatives such as methotrexate, azathioprine or ciclosporin. Hydroxychloroquine has also been used as an antifibrotic agent. Due to the rarity of the disease, no controlled treatment trials have been conducted. It is important that children have all their vaccinations including annual flu vaccine. Some children may need long-term support with oxygen. Lung transplant may be an option in some children.
Prognosis: The prognosis is very variable. There may be complete recovery, partial response with long term problems or no response at all. The overall death rate is 15-30% and the recurrence rate within families is 1 in 8.
http://www.arnold.org.au