Humidifier disinfectant-associated children's interstitial lung disease: Computed tomographic features, histopathologic correlation and comparison between survivors and non-survivors.

Objectives: To report radiologic findings with histopathologic correlations of humidifier disinfectant-associated children's interstitial lung disease (HD-chILD) and to compare computed tomography (CT) findings between survivors and non-survivors.

Methods: Forty-seven children with HD-chILD (27.4 ± 12.4 months old) were categorized as survivors (n = 25) and non-survivors (n = 22). The patterns, distributions, and chronological changes in lung lesions at follow-up CT were investigated. Histopathologic correlations were performed in 23 patients.

Results: CT features were characterized by chronological changes, from consolidation to centrilobular opacities, and lesions eventually became faint centrilobular nodules. Histopathologic features were bronchocentric-distributed fibro-inflammatory lesions, which were more profound in the advanced stage than the early stage. Consolidation ≥ 30 % [hazard ratio (HR), 2.932], centrilobular opacities ≥ 60 % of the total lung volume (TLV; HR, 0.206) and spontaneous air leaks (HR, 3.457) were significant factors associated with patient survival, as per univariate analysis. Consolidation ≥ 30 % (HR, 3.519), centrilobular opacities ≥ 60 % (HR, 0.205) and diffuse ground glass opacity (GGO) ≥ 70 % of the TLV (HR, 3.521) were significant factors associated with patient survival, as determined via multivariate analysis.

Conclusion: Distinctive chronological CT features were observed in the HD-chILD images. Spontaneous air leaks, consolidation, GGO, and centrilobular opacities were prognostic factors.

Key Points: Chemical disinfectants can induce severe inhalation lung injury. Lung injury caused by inhaled disinfectants demonstrates chronologic changes in radiologic findings. Understanding of radiological characteristics is important to predict outcomes in chemical pneumonitis. Physicians should be aware of the potential risk of environmental chemicals.