Is lung ultrasound useful in diagnosing and monitoring children with neuroendocrine cell hyperplasia of infancy?

Abstract

Background: Neuroendocrine cell hyperplasia of infancy (NEHI) is an idiopathic interstitial lung disease (ILD) of childhood. HRCT is a gold standard in diagnosis of NEHI. As HRCT has some limitations, lung ultrasound (LUS) arouses great interest as an alternative imagine method in some pulmonary diseases in children. Objective: The study was aimed to evaluate the usefulness of LUS in diagnosis and monitoring of NEHI. Methods: This was a prospective study that included children with NEHI diagnosed between 2014 and 2015. In patients with NEHI LUS and HRCT was performed at baseline. Follow-up LUS was repeated after 6 and 12 months from the initial diagnosis. Control group underwent LUS at baseline. Results: Thirteen children with NEHI (11 boys, median age 13 months (8-47 IQR)) were included. The main USG findings were B-lines, pleural line irregularities and pleural line thickening. B-lines were found in 13 children (100%) from the study group and in 6 (46.2%) from the control group (p=0.002). The number of B-lines in all assessed lung areas was significantly higher in children with NEHI. The study groups differed significantly in terms of pleural line irregularities and pleural line thickening. ILD indices found in a quantitative CT analysis correlated significantly with the number of B-lines in every assessed area. We did not found significant changes in LUS abnormalities between baseline and follow-up assessment. Conclusions: Although LUS is sensitive in diagnosing lung involvement in NEHI, its diagnostic specificity is low and does not enable a reliable diagnosis of NEHI. It seems that LUS might be useful in following patients with NEHI, but longer observation is needed.