Neuroendocrine cell hyperplasia of infancy: diagnosis with high-resolution CT.

OBJECTIVE: Neuroendocrine cell hyperplasia of infancy is a form of childhood interstitial lung disease originally reported as persistent tachypnea of infancy. Reports of small series of cases and anecdotal experience have suggested that this disorder may have a consistent CT pattern. The purpose of this study was to review the CT findings in children with neuroendocrine cell hyperplasia of infancy to determine the findings at high-resolution CT, the diagnostic accuracy of CT compared with biopsy, and interrater reliability. MATERIALS AND METHODS: Images from 23 CT examinations of children with biopsy-proven neuroendocrine cell hyperplasia of infancy and six CT examinations of children with other childhood interstitial lung diseases were reviewed by two pediatric radiologists with special expertise in thoracic imaging. Identifying digital data were removed, and images were reviewed without clinical data. A CT assessment form was completed for each patient. RESULTS: Ground-glass opacification was the most common finding in patients with neuroendocrine cell hyperplasia of infancy. The right middle lobe and lingula were most commonly involved. Air trapping with a mosaic pattern was the second most common finding. Interrater reliability was very good with a kappa value of 0.93. The sensitivity and specificity of CT in the diagnosis of neuroendocrine cell hyperplasia of infancy were at least 78% and 100%. CONCLUSION: Neuroendocrine cell hyperplasia of infancy can have a characteristic appearance on high-resolution CT scans, the imaging findings being useful in differentiating neuroendocrine cell hyperplasia of infancy from other types of childhood interstitial lung disease. The appearance aids radiologists in suggesting a specific diagnosis but does not exclude this diagnosis; in 17-22% of cases, the readers in this study did not suggest the diagnosis of neuroendocrine cell hyperplasia of infancy when it was present.

Abnormal infant pulmonary function in young children with neuroendocrine cell hyperplasia of infancy.

RATIONALE: Lung function in children with neuroendocrine cell hyperplasia of infancy (NEHI) and correlations with future clinical outcomes are needed to guide clinical management. OBJECTIVE: To compare results of infant pulmonary function tests (IPFTs) in children with NEHI to disease control (DC) subjects and to correlate NEHI IPFTs with future outcomes. METHODS: We performed a retrospective, single center study of IPFT in subjects diagnosed by lung biopsy (NEHI) or clinically (NEHI syndrome) and in DC subjects evaluated for cancer or pre-hematopoietic stem cell transplantation (HSCT). Raised volume rapid thoracoabdominal compression (RVRTC) and plethysmography were performed on all infants and evaluated for quality. Standard spirometry measures, room air oxygen saturations (RA O2 sat), and weight percentiles were collected during follow up. MEASUREMENTS AND MAIN RESULTS: Fifty-seven IPFTs were performed in 15 NEHI, 22 NEHI syndrome, and 20 DC subjects. RVRTC and FRC measurements were obtained in 85% or more of subjects in all groups. Significant airflow limitation (FEV0.5 P-value ≤ 0.01) and air trapping (FRC P-value ≤ 0.01) were seen in NEHI and NEHI syndrome subjects compared to DCs. No significant correlations were found between IPFT, oxygen use, RA O2 sat, and weight at the time of the IPFTs. Initial FEV0.5 and FRC z-scores correlated with RA O2 sat (r = 0.60 and -0.49) at short-term follow up (6-12 months). Most measurements of RVRTC correlated with FEV1 (n = 5) measured 4-5 years later (r > 0.50). CONCLUSIONS: IPFTs in NEHI subjects are feasible, demonstrate significant obstruction and air trapping, and correlate with future RA O2 sat and FEV1 . IPFTs may provide valuable clinical information when caring for NEHI patients. Pediatr Pulmonol. 2013; 48:1008-1015. © 2012 Wiley Periodicals, Inc.