OBJECTIVETo investigate the high-resolution computed tomographic (HRCT) features of infants with diffuse lung disease (DLD) for improving the diagnostic accuracy clinically.

METHODTotally 75 infants under 2 years of age with DLD (2010-2013) were involved in this study. Among them, 56 were males and 19 females, aged from 2 days to 24 months (mean age was 10.9 months). According to the clinical or pathological data, the cases were enrolled into three groups, including systemic diseases-associated infantile DLD (30 cases), alveolar structure disorders-associated infantile DLD (23 cases), and infantile DLD specific to infancy (22 cases). Retrospectively, HRCT images, from the three groups respectively, were analyzed and compared. HRCT presentations including airway disorders, interstitial disorders and air space disorders were reviewed. Inter-reviewers consistency check was performed, the consistency between reviewers was good (K = 0.64;P = 0.03, < 0.05), as well as χ(2) test.

RESULTAmong the three groups, some of the HRCT sings (bronchiectasis, thickened bronchiolar wall, mosaic sign, reticular, intralobular nodules and consolidations) had significant differences (χ(2) = 24.52, 6.08, 18.00, 12.56, 9.11 and 11.50, P < 0.05) .

CONCLUSIONThe HRCT features of infantile pulmonary DLD/interstitial LD with different causes were as follows, compared to the other two groups, intralobular nodules was the main feature of the systemic diseases-associated infantile DLD, thickened bronchiolar wall, mosaic sign and consolidations were rare as well. Meanwhile, bronchiectasis was more common in alveolar structural disorders-associated infantile DLD, and reticular opacity was rarely seen. Associated clinical data, the HRCT presentations would help clinicians to make accurate diagnosis.