Childhood Interstitial Lung Disease Standardised Operating Procedure – Genetic Testing

This information paper, developed by Lung Foundation Australia in collboration with chILDRANZ, provides a standardised operating procedure for genetic testing in children with suspected childhood interstitial lung disease (chILD). Genetic causes of interstitial (diffuse parenchymal) lung diseases are rare but important to identify, as they can inform prognosis, guide treatment, and have implications for family members. The document outlines best-practice protocols for selecting and interpreting genetic tests in neonates, infants, toddlers, and older children presenting with prolonged respiratory symptoms, abnormal pulmonary function, or radiological evidence of diffuse lung disease. It recommends excluding infection, cardiac, and metabolic causes before proceeding to genetic analysis and highlights the increased likelihood of inherited disease when a positive family history is present.

The resource details the range of genetic tests available, including chromosomal microarray, single gene testing, surfactant panels, whole exome sequencing (WES), and whole genome sequencing (WGS). These are explained using analogies to help families understand the complexity of testing, from reading a single book (single gene test) to analysing an entire library (WGS). It also explains the importance of trio testing—comparing the genetic data of a child with their parents—to improve interpretation of potential disease-causing variants. A key part of the protocol is obtaining informed consent, with full disclosure of the possible implications, such as incidental findings, insurance consequences, and emotional impact.
The paper stresses the need to provide detailed clinical information to the analysis team and encourages collaboration with genetic counsellors, particularly when delivering results to families. It also recommends collecting a skin sample during lung biopsy for potential future functional studies. This evidence-informed guide produced by Lung Foundation Australia and chILDRANZ supports accurate diagnosis, informed decision-making, and personalised management for children with genetic lung diseases, and is an essential resource for respiratory clinicians, genetic specialists, and paediatric teams involved in chILD care.