Lung Fibrosis Affects One in Five Children With chILD

PULMONARY fibrosis affects approximately one in five children with childhood interstitial lung disease (chILD) and is associated with poorer lung function and survival, according to a European multicentre study. 

The findings highlight the importance of recognising fibrosing disease in children with rare interstitial lung conditions and suggest that standardised diagnostic criteria could support earlier identification of patients who may benefit from targeted treatment.  

Investigating Fibrosis in Childhood Lung Disease 

Childhood interstitial lung disease encompasses a heterogeneous group of rare conditions affecting the lung tissue and surrounding structures. 

Although pulmonary fibrosis is recognised as an important complication, its prevalence and relationship with long-term clinical outcomes have not previously been systematically established in large paediatric cohorts. 

Researchers analysed data from the chILD-EU register, which includes children and adolescents from 23 European countries. 

The prospective study examined 1,071 patients aged 0–18 years, with data collected between March 2004 and July 2025. 

Researchers assessed pulmonary fibrosis using two definitions: predefined register criteria and a more restrictive definition used in clinical trials. 

CT scans and lung biopsy findings underwent centralised peer review, while pulmonary function and survival were assessed longitudinally.  

One in Five Children Met Fibrosis Criteria 

Of the 1,071 children included, 220 fulfilled the register definition of pulmonary fibrosis, corresponding to a prevalence of 20.5%. 

Using the clinical trial definition, fibrosis was identified in 62 of 534 children, equivalent to 11.6%. 

The median age at study inclusion was 2.4 years. 

Children meeting either definition of pulmonary fibrosis had consistently poorer lung function than those without fibrosing disease. 

Measured using percent predicted forced vital capacity, lung function was approximately 15–20% lower among children with fibrosis across follow-up visits extending to eight years. 

These findings indicate that fibrosing disease is associated with a substantial and persistent reduction in respiratory function during childhood.  

Fibrosis Associated With Poorer Survival 

Survival after enrolment was significantly lower among children meeting the register definition of pulmonary fibrosis. 

The unadjusted hazard ratio for death or lung transplantation was 1.64 compared with children who did not fulfil the fibrosis criteria. 

This association persisted after adjustment for sex, age category, and BMI z-score. 

Although children meeting the clinical trial definition showed a similar pattern, the survival association did not reach statistical significance in that smaller group. 

The researchers suggest that standardised fibrosis assessment could help clinicians identify children at increased risk of adverse outcomes and support more consistent selection of patients for future therapeutic trials. 

However, the study was observational and did not evaluate whether antifibrotic treatment improves outcomes in children with chILD. 

Further research is therefore required to establish the effectiveness and safety of antifibrotic therapies in paediatric populations. 

The findings nevertheless demonstrate that pulmonary fibrosis is a clinically important feature of childhood interstitial lung disease, with implications for both respiratory function and survival.  

Reference 

Griese M et al. Prevalence and disease trajectories of pulmonary fibrosis of childhood interstitial lung disease: a register-based, multicentre observational study. Lancet Respir Med. 2026;14(9):786–796. doi:10.1016/S2213-2600(26)00052-4.